723002 manual rev g

Serial Number _____________

CORRDATA® SYSTEMREFERENCE MANUAL

CORRDATA® Basic Software for use with RDC-CORROSOMETER®,RDC-CORROTEMP™ CORROSOMETER®, RDC-CORRATER®,

RDC-CORROTEMP® CORRATER®, CORROSOMETER®, CORROTEMP™

CORROSOMETER®, and CORRATER® probes

ROHRBACK COSASCO SYSTEMS, INC.11841 E. Smith AvenueSanta Fe Springs, CA 90670Tel: (562) 949-0123

(800) 635-6898Fax: (562) 949-3065 P/N 723002-Man Rev. G

12-98

Contents

CORRDATA™ Corrosion Monitoring System© 1991 - 94 Rohrback Cosasco Systems Inc. All rights reserved.

CORRDATA, CORROSOMETER, CORRATER, CORROTEMP, and COSASCO are registeredtrademarks, and ICMS is a trademark of Rohrback Cosasco Systems Inc.

MS, MS-DOS are registered trademarks of Microsoft Corporation.LaserJet, PaintJet, DeskJet are registered trademarks of Hewlett-Packard Company.IBM, proprinter are registered trademarks of International Business Machines CorporationLotus 1-2-3 is a registered trademark of Lotus Development Corporation.

No part of this manual may be reproduced or transmitted in any form or by any means, electronicor mechanical, including photocopying and recording, for any purpose, without the express writtenpermission of Rohrback Cosasco Systems, Inc.

i

Contents

Chapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Chapter 2 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

RDC Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5CORRDATA Mate I & II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6PC Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Chapter 3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Installing an RDC Unit on a Probe . . . . . . . . . . . . . . . . . . . . . . . 10Intrinsic Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15CORRDATA Mate I & II . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16CORRDATA Basic PC Software . . . . . . . . . . . . . . . . . . . . . . . . 18

Chapter 4 System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

RDC's - Remote Data Collector . . . . . . . . . . . . . . . . . . . . . . . ..21CORRDATA Mate I & II . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22CORRDATA Basic PC Software . . . . . . . . . . . . . . . . . . . . . . . . 22

Chapter 5 System Configuration Procedures . . . . . . . . . . . . . 25

System Configuration from the PC. . . . . . . . . . . . . . . . . . . . . . . 25Setting the Clock on the Mate II . . . . . . . . . . . . . . . . . . . . . . . . 32System Configuration from Mate I & II . . . . . . . . . . . . . . . . . . . 33Configuration of Probes with RDC's . . . . . . . . . . . . . . . . . . . . . 41Configuration of Probes without RDC's . . . . . . . . . . . . . . . . . . . 45Choosing Probe Reading Frequency on RDC's . . . . . . . . . . . . . . . 45Clearing Memory on CORRDATA Mate I & II . . . . . . . . . . . . . . 47Clearing Memory on RDC's . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Contents

ii

Chapter 6 Normal Operating Procedures . . . . . . . . . . . 49

Collecting Stored Data from RDC's . . . . . . . . . . . . . . . . . . . . . . 49Collecting Data from Probes without RDC's . . . . . . . . . . . . . . . . 52Displaying Probe Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Replacing a CORROSOMETER or CORROTEMP CORROSOMETERprobe of the same type on an RDC . . . . . . . . . . . . . . . . . . . . . . . 58Replacing a CORROSOMETER or CORROTEMP CORROSOMETERprobe of a different type on an RDC . . . . . . . . . . . . . . . . . . . . . 60Replacing a CORROSOMETER or CORROTEMP CORROSOMETERprobe of the same type without an RDC (Mate II only) . . . . . . . . . 60Replacing CORRATER or CORROTEMP CORRATERProbe Electrodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61RDC Battery Check and Replacement . . . . . . . . . . . . . . . . . . . . . 62Transferring Collected Data to PC. . . . . . . . . . . . . . . . . . . . . . . 63Resolving any Data Merging Conflicts . . . . . . . . . . . . . . . . . . . . 65Archiving and Retrieving Old Data Files . . . . . . . . . . . . . . . . . . . 67

Chapter 7 Corrosion Data Analysis . . . . . . . . . . . . . . . . . . . . . 71

Displaying CORROSOMETER and CORROTEMPCORROSOMETER Metal Loss Data . . . . . . . . . . . . . . . . . . . . . 72Editing and Analyzing CORROSOMETER Probe Graphs . . . . . . . . 74Displaying CORRATER and CORROTEMP CORRATERCorrosion Rate Data Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Editing and Analyzing CORRATER Probe Graphs . . . . . . . . . . . . 78Displaying Temperature on CORROTEMP Probe Versions . . . . . . 80Printing Corrosion Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Test Graphical Displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Chapter 8 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

RDC Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85CORRDATA Mate I & II . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85PC CORRDATA Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86Software Revisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Contents

iii

Chapter 9 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

RDC Unit Power Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89Checking Functional Operation of RDCwith Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89Mate I & II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95Checking Mate II Operation on Probes . . . . . . . . . . . . . . . . . . . . 95Mate I & II Self Check System Reprogramming Utility . . . . . . . . . 95PC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96If Problems Still Occur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Chapter 10 ASCII Transfer Utility . . . . . . . . . . . . . . . . . . . . . . . . 97

Chapter 11 Mate Operation with Downhole Corrosion Monitor System (DCMS) . . . . . . . . . . . . . . . . . . . . . 99

Appendix ATheory of Operation of CORROSOMETER Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

Appendix BTheory of Operation of CORRATER®Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Appendix CSpecial Conditions or Limitations for use ofIntrinsically of Safe Equipment to EuropeanHarmonized Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

Appendix DLithuim Battery Pack Material Safety Data Sheet,Handling and Transportation . . . . . . . . . . . . . . . . . . . . . . 165

Appendix ECORRDATA System CertificationInterconnect Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

Appendix FOperation of CORRDATA Basic SoftwareWith Windows 95 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

Contents

iv

Figures and Drawings

Figure Page

1.1 CORRDATA Measurement System . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2 Data Transfer from CORRDATA Mate I & II to PC. . . . . . . . . . . . . . . . 2

3.1A Single Channel RDC (Metal Enclosure) Mounting Dimensions . . . . . . . 10

3.1B Single Channel RDC (Plastic Enclosure) Mounting Dimensions . . . . . . . 11

3.2A Connecting RDC Batteries - Version I . . . . . . . . . . . . . . . . . . . . . . . 12

3.2B Connecting RDC Batteries - Version 2 . . . . . . . . . . . . . . . . . . . . . . . 13

3.2C RDC Unit Version 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

3.3 CORRDATA Mate I & II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.4 Mate I & II Start-Up Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.5 Cursor and Low Battery Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1 Typical RDC-CORROSOMETER Probe Entry Screen . . . . . . . . . . . . . 23

4.2 Typical CORROSOMETER Probe Metal Loss Graph . . . . . . . . . . . . . 23

5.1 Main Menu Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

5.2 Configuration Mode - Probe Listing Summary . . . . . . . . . . . . . . . . . . 26

5.3 Configuration Mode - Input Selection . . . . . . . . . . . . . . . . . . . . . . . . 27

5.4 Configuration Mode - Information Entry Screen . . . . . . . . . . . . . . . . . 27

5.5 CORROSOMETER or CORROTEMP CORROSOMETERProbe Types and Spans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

5.6 Battery Life with RDC - CORROSOMETERor CORROTEMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Contents

v

5.7 Battery Life with RDC - CORRATER . . . . . . . . . . . . . . . . . . . . . . . 47

6.1 CORRDATA PC Software Main Menu . . . . . . . . . . . . . . . . . . . . . . . 63

6.2 Resolving Conflicts during Receive Operation . . . . . . . . . . . . . . . . . . 66

Contents

vi

Figures and Drawings (continued)

6.3 CORRDATA PC Software File Saving . . . . . . . . . . . . . . . . . . . . . . . 67

6.4 CORRDATA PC Software File Retrieval . . . . . . . . . . . . . . . . . . . . . 69

7.1 Probe Display Selections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

7.2 CORROSOMETER Probe Metal Loss Graph . . . . . . . . . . . . . . . . . . . 73

7.3 CORROSOMETER Metal Loss Graph with Rate Date Display . . . . . . . 75

7.4 CORROSOMETER Probe Selecting Y-Range . . . . . . . . . . . . . . . . . . 76

7.5 CORROSOMETER Probe Selecting X-Range . . . . . . . . . . . . . . . . . . 76

7.6 CORRATER Probe Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

7.7 CORRATER Probe - Selecting Y-Range . . . . . . . . . . . . . . . . . . . . . . 80

7.8 CORROSOMETER Test Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

7.9 CORRATER Test Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

1

Figure 1.1 CORRDATA Measurement SystemFigure 1.1 CORRDATA Measurement System

Chapter 1Introduction

2 CORRDATA Reference Manual

The CORRDATA Corrosion Management system is extremely flexible in its operation. The MateI & II operate with Remote Data Collectors (RDC's) to gather time-related corrosion data, evenfrom remote locations where power is unavailable. In addition, the Mate II allows for automateddata collection directly from CORROSOMETER, CORROTEMP CORROSOMETER andCORRATER probes used without an RDC.

CORROSOMETER probes measure metal loss in any process environment. CORRATER probesdirectly measure corrosion rates in sufficiently conductive fluids, normally water. CORROTEMPversions of the probes add temperature measurement to assist in the correlation of corrosion rateswith temperature.

RDC's combined with probes take and store readings at pre-programmed intervals for retrieval bythe Mate I & II and transfer to your PC. This provides continuous time-related history,complementary to the continuous, on-line ICMS (Integrated Corrosion Monitoring Systems) usedprimarily in process plants.

Figure 1.2 Data transfer from CORRDATA Mate I & II to PC

The RDC-CORROSOMETER or RDC-CORROTEMP CORROSOMETER units take automaticreadings from a probe at pre-programmable time intervals ranging from 5 minutes to 24 hours.The data is time-stamped and stored for later retrieval. The RDC-CORRATER and RDC

Chapter 1 Introduction 3

CORROTEMP CORRATER units have a corresponding range of time intervals from 30 minutesto 24 hours.

The Mate II also automates direct reading and logging of probes, without an RDC. This avoidspotential errors from incorrect recording of readings.

A basic CORRDATA software package is included free of charge with the Mate I & II for DOSbased PC's. This copyrighted software provides for system configuration, storage andmanipulation of the corrosion data.

5

Chapter 2Specifications

RDC Units

Electronics

Ë RDC - CORROSOMETER unit (RDC-CO) compatible with allCORROSOMETER probes

Ë RDC - CORROTEMP CORROSOMETER unit (RDC-COT) compatible with allCORROTEMP CORROSOMETER and CORROSOMETER probes

Ë RDC - CORRATER unit (RDC-CA) with solution resistance compensation (SRC)compatible with all CORRATER probes

Ë RDC - CORROTEMP CORRATER unit (RDC-CAT) with solution resistancecompensation (SRC) compatible with all CORROTEMP CORRATER andCORRATER probes

Ë Output: RS 232 to CORRDATA Mate I and CORRDATA Mate II

Ë Battery Life:

RDC - CO and RDC - COT14 Ah Battery Pack - Typical life 177 days @ 1 reading/hour

RDC4 - COT14 Ah Battery Pack - Typical life 177 days @ 1 reading/4 hour

RDC - CA and RDC - CAT probes:14 Ah Battery Pack - Typical life 91 days @ 1 reading/hour

Ë Reading Storage:

RDC - CO: 2048 ReadingsRDC - COT: 1024 ReadingsRDC - CA: 1024 ReadingsRDC - CAT: 512 Readings


Ë Repeatability over temperature range -40oF to +160oF (-40oC to +70oC)

RDC - CORROSOMETER:Typical ± 0.1% of probe span on W40 carbon steel probeTypical ± 0.5% of probe span on T20 carbon steel probeTypical ± 0.5% of probe span between RDC units

RDC - CORRATER UnitTypical ± 0.75% of 20 mpy span at 5 mpy on carbon steel, based ona Randl's equivalent circuit with Cdl 10 µF/cm2, conductivity 250µmhos, and 5 cm2 electrodes

RDC - CORROTEMP VersionsTemperature range -40° to +260°C, System absolute temperatureaccuracy ±3°C

Mechanical

Ë NEMA 4 (Version 1) or NEMA 4X (Version 2) weatherproof enclosure

Ë Integral 10 foot probe connection cable

Ë Dimensions 7.5"H x 6.25"W x 4.25"D ( 190.5 mm x 158.7 mm x 108 mm )

Ë Weight 7 lbs. (3.2 Kg)

Ë Weatherproof RS 232 connector

CORRDATA Mate I & II

Electronics

Ë Sealed membrane keyboard

Ë Battery Powered:

6 x AA Alkaline cells - Typical life 10 hours continuous reading onlyRDC's

6 hours continuous reading only probes (Mate II only)

Ë Communication with RDC and PC adapter cable "Mate to RDC" cable

Chapter 2 Specifications 7

Ë Communication with CORROSOMETER and CORROTEMP CORROSOMETERprobes via "CORROSOMETER cable" (Mate II only)

Ë Communication with CORRATER and CORROTEMP CORRATER probes via"CORRATER cable" (Mate II only)

Ë Supplied with RDC test probes

Ë Automatic power shut off in 45 secs after reading or non-use

Mechanical

Ë Splash-proof enclosure

Ë Dimensions 7.75"H x 4.30"W x 2"D ( 196.8 mm x 109.2 mm x 50.8 mm )

Ë Supplied in carrying case

Ë Weight without carrying case 1.5 lb. ( 680g )

Ë Weight with carrying case 5.5 lb. ( 2.5 Kg )

Environmental

Ë Temperature range:Operating - 0oF to 122oF ( -18oC to 50oC )Storage - 0oF to 150oF ( -18oC to 70oC )

Ë Humidity 0 - 95% ( non-condensing )

PC Requirements

Ë IBM PC or compatible

Ë VGA or EGA graphics

Ë 640k memory

Ë 1 floppy disk drive

Ë Hard disk (Memory requirement: 400K plus 40K per RDC)

Ë MS DOS 3.3 or higher operating system ( MS DOS 4.01, 5.0, 6.0 or 6.2 preferred)


Ë Serial port available (adapter cable provided for easy access to Mate I & II cable)

9

Chapter 3Installation

NOTE: Your CORRDATA system components were carefully tested,inspected and packaged prior to shipment. Before unpacking theinstruments, please inspect the packaged materials for shippingdamage and retain damaged packaged materials to support any claimagainst your freight carrier should this become necessary.

Unpacking

Carefully remove the instruments from their packages. Included in the package you shouldfind:


Ë Hand held CORRDATA Mate I or II unit.Ë Instrument carrying case.Ë "Mate to RDC" cable for use with RDC's and PC adapter cable.Ë "CORROSOMETER" cable for use with CORROSOMETER and

CORROTEMP CORROSOMETER probes. (Mate II only)Ë "CORRATER" cable for use with CORRATER and CORROSOMETER

CORRATER probes. (Mate II only)Ë "Mate to PC" RS 232 serial port connector assembly (3 ft) with 25 pin D

type connector for PC serial port.Ë 25 pin to 9 pin adapter serial port adapter.Ë CORRDATA System Quickstart and Reference Manuals.Ë CORRDATA System Diskette.Ë CORROSOMETER test probe.Ë CORRATER test probe.

Remote Data Collector Unit

Ë RDC unit in NEMA 4 wall mounting enclosure with integral 10 foot probe toinstrument cable and probe connector.

Ë Battery pack (mounted inside the RDC).


Installing an RDC unit on a probe

RDC units permit unattended reading and logging of probes at pre-programmed intervalsto provide continuous corrosion data for latter analysis.

WARNING! Before installing the RDC unit, verify that you havethe correct RDC for the CORROSOMETER, CORROTEMPCORROSOMETER, CORRATER, or CORROTEMP CORRATERPROBE to be monitored, and that the cable connector on the RDCunit matches the probe connector.

NOTE: If your RDC has a Type A probe connector use a Type A toType B adapter P/N 028030 for probes with a Type B connector.

The RDC unit should be mounted adjacent to the probe that is to be monitored and in aposition that permits easy access for data collection by the Mate I or II. Figure 3.1A showsthe RDC unit and its mounting hole dimensions.

Figure 3.1A Single Channel RDC (Metal Enclosure) Mounting Dimensions

Chapter 3 Installation 11

Fig. 3.1B Single Channel RDC (Plastic Enclosure) Mounting Dimensions

The RDC unit is supplied with a 10 ft. long probe cable which meets most installationrequirements. Longer cable lengths are permissible on a special order basis with amaximum length of 100 ft. No external power supply is necessary since the unit is batteryoperated. For Solar powered options, and remote modem or cellular phone communicationcontact Rohrback Cosasco Systems about Communication Power Modules (CPM's)

NOTE: The instrument to probe cable specification is critical to theperformance of the instrument. No substitutes should be made withoutconsultation with the factory.

Within the RDC, memory back up of data is provided by a small rechargeable battery.This battery is separate from the main battery supply to avoid loss of data even when themain batteries have expired, and provides a back up for approximately 3 months. Thisbattery must be switched ON before connecting the main battery and before start up of theunit by setting the DIP switches, item 1, to ON as shown in Figure 3.2A for metal


enclosure units, or setting DIP switch number 1 to ON, item 1, as shown on Figure 3.2Bfor plastic enclosure units.

WARNING! If the memory back up cell is not connected, storeddata in the RDC will be lost if the main batteries run down, or whenthe main batteries are changed. In addition if the back up batteryis switched ON after connecting the main battery at start up erraticdata will be recorded.

The main Lithium battery pack is installed in the RDC unit as supplied, but with the plug,item 2, left unconnected to avoid battery drainage. Lithium batteries are used exclusivelyin the RDC because of their much greater capacity than conventional batteries. The twopin plug, item 2, should be connected to the circuit board connector item 3 as shown inFigure 3.2A, 3.2B or 3.2C prior to setting the RDC into operation.

Figure 3.2A Connecting RDC Batteries - Version 1


Fig. 3.2B Connecting RDC Batteries - Version 2

WARNING! It is extremely important for correct operation andcorrect intrinsic safety readings to use the correct battery asoriginally supplied in the RDC unit and identified inside the lid ofthe RDC

RDC 14 Ah Battery Packs

Non Intrinsically Safe RDC - P/N 748065-3Intrinsically Safe RDC - RDC-CO & RDC-CA only - P/N 748073-3UL/CSA Certified RDC - RDC-COT & RDC-CAT only - P/N 748100-3BASEEFA Certified RDC-RDC-COT & RDC-CAT only - P/N 748073-3


Fig. 3.2C RDC Unit - Version 3

NOTE: RDC Version 3 the main battery must be tested seperatelyon a test plug which connects to item 2. Normally a bad battery isindicated by a loss of communication between the RDC and Mate.

To test the battery condition press push-button, item 4, and check that the red indicator,item 5, adjacent to the battery connector illuminates (for more information see "RDCBattery Check and Replacement" in Chapter 6).

Once the RDC unit has been mounted and the probe cable connected to the probe, theconnector clamp ring must be firmly tightened.


WARNING! Care should be taken to see that any regulationsthat exist in your area regarding the shipment and disposal oflithium batteries are met. See Appendix D for further details andMaterials Safety Data Sheet (MSDS) for the battery pack.

Intrinsic Safety

The probes, RDC units, and Mate I & II systems have intrinsic safety ratings for use inelectrical hazardous area environments. Applicable certifications are identified on theSystem components according to units ordered.

The intrinsically safe system has been certified with a rating of EEx ia IIC T4 attemperatures of up to 500C. For temperatures from 500C to 700C the rating is EEx iaIIC T3. This means that the system is safe for use in the severest of electrical hazardousareas, where explosive gases are always present (Zones 0, 1, and 2; Divisions 1 and 2,all groups) even with up to two fault conditions (designated by ia).

The gas classification IIC is the most stringent including gases such as acetylene andhydrogen. This part of the rating relates to the spark energy that is required to create anexplosion.

Gases have a separate classification for explosive tendency based on hot surfacetemperatures which are not necessarily the same as the spark ignition energy. Thetemperature rating T4 indicates that no temperature of the equipment exceeds 1350C at500C even under fault conditions. This rating includes all listed gases except carbondisulfide (which requires T5 rating)

Care must be taken with intrinsically safe systems to maintain their carefully designedintegrity. The major features to note are as follows:

1. Mate I or II batteries must be replaced in a safe area.

2. Only the correct RDC batteries must be used, since they have integralcurrent limiting devices to permit their replacement in the hazardous area.

3. Only the intrinsically safe "Mate to PC" cable should be used between theMate I or II and the PC even though this is in the safe area. This preventsany excess power from being passed onto the Mate II, which could then becarried into the hazardous area.

4. Absolutely no substitution of parts or unauthorized repairs must beundertaken or the certifications are rendered invalid.


See Appendix C for intrinsic safety certification documents relating toBASEEFA/CENELEC approvals.


The Mate I or II is supplied with a set of six 1.5 V AA alkaline batteries. To installthese batteries remove the access panel on the back of the unit (see Figure 3.3) andinstall the batteries with the polarities as indicated.

Figure 3.3 CORRDATA Mate I & II

To check that the unit is operational press the ON button. The screen should appear asin Figure 3.4.


ROHRBACK COSASCOSYSTEMS

Read Disp Dump SetUp

> > > >

F1 F2 F3 F4

Figure 3.4 Mate I & II Start-Up Screen.

If the batteries are low or in need of replacement, the cursor on the screen will alternatethe standard cursor with cursor LB (see Figure 3.4).

Figure 3.5 Cursor and Low Battery Indicator

Battery back up for memory in the Mate I & II is provided by lithium batteries mountedinternally within the unit. These batteries should provide 7-10 years of back upcapacity. Replacement of these batteries requires the unit to be returned to RohrbackCosasco Systems or an authorized dealer.


CORRDATA Basic PC Software

The minimum requirements for the PC are as follows:

Ë IBM PC or compatible.

Ë EGA/VGA graphics card.

Ë 640 K memory.

Ë One floppy disk drive.

Ë Hard disk.

Ë MS-DOS 3.3 or higher operating system (MS-DOS 4.01, 5.0, 6.0 or 6.2preferred).

Ë Serial port on the PC.

The CORRDATA basic software package is included with the CORRDATA Mate uniton 3 ½" diskettes.

To install the CORRDATA software, place the appropriate diskette in your floppydrive. At the DOS prompt, change the drive to this floppy and type install. Theprogram gives the choice of the directory where the files are to be installed and theserial port COM1 or COM2 to be used. Follow the on-screen instructions.

The default for the directory is CORRDATA installed in the root directory on the Cdrive.

When the installation is complete, remove CORRDATA Software diskette and save asa backup.

For users of Microsoft Windows it is possible to run the CORRDATA Software as aDOS application under Windows. Set the Command line to CD2 as applicable and setthe working directory to CORRDATA. See the Windows manual for details.

To commence the program in DOS select the CORRDATA directory and then type"CD2". If using Windows double click on the Icon for CORRDATA.

Fit the "Mate to RDC" cable to the Mate I or II and connect it via the "Mate to PC"cable to the required serial port, COM 1 or COM2, of your PC. The "Mate to PC"cable brings the Mate I or II to PC connection to the front of the PC for ease of use. Onintrinsically safe units this cable also includes special isolation components.


The serial port on the PC has either a 9 pin or 25 pin connector. If it has a 9 pin serialport, you will need to use the 25 pin to 9 pin adaptor supplied with the cable assembly.

21

CORROSOMETER (CO)CORROSOMETER (CO) CORROTEMP CORROSOMETER (COT)CORROTEMP CORROSOMETER (COT)

CORRATERCORRATER (CA)(CA) CORROTEMP CORRATER (CAT)CORROTEMP CORRATER (CAT)

Chapter 4System Overview

RDC's-Remote Data Collectors

There are several versions of RDC's including a CORROTEMP temperature measurementunit. The options and capabilities for CORROSOMETER and CORROTEMPCORROSOMETER units are as follows:

RDC UNIT

PROBES

Metal Loss Temp Metal Loss Temp

RDC-CO

RDC-COT OR RDC4-COT Configured as RDC-CO

RDC-COT or RDC4-COTConfigured as RDC-COT

YES

YES

YES

NO

NO

-200C 1

YES

YES

YES

NO

NO

YES

1 Default display with open circuit temperature loop

For CORRATER and CORROTEMP CORRATER systems the options and capabilitiesare as follows:

RDC UNIT

PROBES

CorrosionRate Imbalance Temp

CorrosionRate Imbalance Temp

RDC-CA

RDC-CATConfigured as RDC-CA

RDC-CATConfigured as RDC-CAT

YES

YES

YES

YES

YES

YES1

NO

NO

-200C 1

YES

YES

YES

YES

YES

YES

NO

NO

YES

1 Default value with open circuit temperature loop


Once programmed with the probe parameters and the frequency of readings required, theRDC unit "sleeps" between readings to minimize power consumption. At the appropriatetime it powers up the probe and electronics, processes the probe reading, and stores thevalue before going back to sleep. The stored probe reading and times are retrieved asrequired when interrogated by the hand held Mate.


The CORRDATA Mate I is a portable instrument capable of programming and gatheringdata from all RDC's. It does not gather data directly from probes. The CORRDATA MateII is a multi purpose portable instrument capable of programming and gathering data eitherfrom probes monitored by RDC units, or directly from probes without RDC units.

NOTE: The Mate II is not able to directly read the temperature ofCORROTEMP CORRATER probes. This can only be done with anRDC-CAT.

The system configuration can be made with the Mate I or II alone. However, it willnormally be more convenient to set up the probe configuration on the PC and then totransfer this to the Mate I or II, which in turn configures any RDC units.

CORRDATA Basic PC Software

The basic CORRDATA software supplied with the Mate I & II provides the followingfeatures.

Ë Menu style selection.Ë Probe configuration for transfer to the Mate and any RDC units.Ë On-line help screens.Ë Selection of units (mils, millimeters or micrometers).Ë Graphical display of metal loss data for CORROSOMETER and

CORROTEMP CORROSOMETER probes.Ë Graphical display of metal loss and temperature from CORROTEMP

CORROSOMETER probes.Ë Graphical display of corrosion rate and imbalance from CORRATER

probes.Ë Graphical displays of corrosion rate, imbalance, and temperature from

CORROTEMP CORRATER probes.Ë Zooming in on graphical displays.Ë Editing of metal loss data to show corrosion rates over selected periods.Ë Up to 9,000 corrosion data points may be displayed for each probe.

A typical RDC CORROSOMETER entry screen is shown below in Figure 4.1, and atypical metal loss graph output is shown in Figure 4.2

Chapter 4 System Overview 23

Figure 4.1 Typical RDC CORROSOMETER Probe Entry Screen

4.2 Typical CORROSOMETER Probe Metal Loss Graph

25

Chapter 5System Configuration Procedures

System Configuration from the PC

System configuration is easily accomplished on the PC with CORRDATA basic software.This configuration is subsequently downloaded to your Mate I or II and then to any RDC'sbeing used. Additional probe location information may also be stored on the CORRDATAsoftware, but is not transferred to the Mate I or II.

To commence system configuration on the PC, select the CORRDATA directory in whichthe CORRDATA program is located and type CD2. Press Enter to clear the RCSCORRDATA introduction screen, and display the main menu. Help screen informationis available via the F1 key for the menu items.

Figure 5.1 Main Menu Screen


For first time configuration select Configure.

NOTE: Menu items may be selected using the cursor keys, space bar,tab (forward), shift + tab (backward) keys and Enter, or by typing thehighlighted letter.

Select Mate/RDC. This will display any existing entries on the probe list together with anentry menu bar, such as the list in Figure 5.2.

Figure 5.2 Configuration Mode - Probe Listing Summary.

For this first time configuration, or for new additions to the existing list, select NEW todisplay the sub-menu of input selections.

Chapter 5 System Configuration Procedures 27

Figure 5.3 Configuration Mode - Input Selection.

Select the appropriate configuration required according to the probe type and whether anRDC will be used with the probe. Press Enter to bring up the information entry screen.For a CORROSOMETER probe with an RDC, the screen would appear as follows.

Figure 5.4 Configuration Mode - Information Entry Screen.The dialogue box provides for all the information needed for this channel. Some itemsmust be completed, while others are optional.


For an RDC-CORROSOMETER unit, the fields that must be completed are:

a) ID Number (Range 1 to 50)b) Type (See Probe or Figure 5.6) c) Span (See Probe or Figure 5.6)d) Reading Interval (See "Choosing Probe Reading Frequency"

in Chapter 5)

Use the 88 or 99 keys to move between the highlighted entry fields. Press the Enter key togain access to the data entry box. Type in the required data, using the backspace, 66 or 77arrows, or delete keys as necessary. For fields with pre-selected values use the 66 or 77arrows. When a field entry is correct, press Enter to complete.

The entry screens for each type of probe are similar except as noted below:

Probe Tag This is an optional field of 12 character maximum, normally used for probetag numbers such as AE 3041. Alternatively, a brief description or locationmay be used. The tag is the only ID description that appears on the MateII. The location field appears only on the PC.

ID No. This is the number to be allocated to this probe or probe/RDC combination.Each ID must be a unique number between 1 and 50, and is the primarymeans of identifying each probe or probe/RDC.

Location This is an informational field only which allows additional identificationinformation up to 30 characters in addition to the tag number field.

Model This is a convenient field to store the probe identification informationNumber which can be useful for reordering purposes. Example: 3500-T10-K03005-

18-0-0-0.

Alloy This is the field for identification of the probe element alloy forCORROSOMETER and CORROTEMP CORROSOMETER probes or theprobe electrode alloy for CORRATER and CORROTEMP CORRATERprobes. Typically the UNS alloy code is used such as K03005 for pipegrade carbon steel. Alternatively Carbon Steel, 304 SS, Monel 400, orother appropriate alloy references may be used if within the 8 charactermaximum.

Type For CORROSOMETER and CORROTEMP CORROSOMETER probesthis is the probe type identified on the probe and detailed in Table 5.1.


For CORRATER and CORROTEMP CORRATER probes the designationE is for standard electrodes (5cm2 electrode surface area) and F for flushelectrodes (0.5 cm2 electrode surface area).

Span (For CORROSOMETER and CORROTEMP CORROSOMETER probesonly). This is identified on the probe and entered in mils even if millimetersor micrometers display units are selected. The mils range is the only figurelisted on the probe for reasons of space.

Multiplier (For CORRATER and CORROTEMP CORRATER probes only). Thisprovides the proportionality constant that applies to different alloys (seeAppendix B). The value may be manually entered or it may be selectedfrom a listing provided of the common alloys. To select from this list pressF5 before entering the selection box, and move the highlight to the requiredalloy. Press Enter to load this value.

Alarm This is provided for informational purposes only. Since the corrosionRate data is historical, active current alarms in the normal sense are not

applicable.

Reading This entry only applies to probes using an RDC, and sets the frequencyInterval with which readings will be taken automatically by the RDC unit. For

information on the selection of the most suitable interval see "ChoosingProbe Reading Frequency" later in this chapter. For the CORRATER orCORROTEMP CORRATER probe, the only minutes selection is 30minutes. Shorter times are not permitted since under some operatingconditions cycle times of up to 30 minutes are required to obtain accuratemeasurements. For RDC4-COT multiplexer units the minimum time thatMUST be set is 15 minutes. If set to a shorter time it will default to 15minutes when configuring the RDC4-COT.

Once all the necessary information has been completed on this screen and is correct, pressF2 to save the information. This will then return to the configuration mode - inputselection Figure 5.3.

Repeat the procedure with the next probe or probe/RDC entry until all the necessary entrieshave been completed. When the final entry has been saved, use the Esc key as necessaryto move back up the menu tree.

To edit any of the entries, select Configure from the main menu to display the existingprobe list summary. Use the arrow keys to move the highlight bar to the required probe.Select Edit from the menu bar. The information entry screen will appear which may thenbe edited as required and saved with the F2 key. If you wish to exit without making anychanges use the Esc key.

WARNING! Editing is primarily for use at initial configuration.Changing probe type, span, multiplier, or time interval after data


has been collected may distort the data and may show up as adiscrepancy for resolution at data merge on the PC (See"Transferring Collected Data to PC in Chapter 6).

To delete an entry select Configure from the main menu to display the probe list. Selectthe required entry with the highlight bar, and select Delete from the menu bar.

Once all the configuration information has been loaded into the PC, the data is ready fortransfer to the Mate I or II, and from there to each probe/RDC combination to configurethe RDC for data collection.

NOTE: If the Mate I or II has been used previously, or used forinitial familiarization, we recommend clearing the Mate I or II memorycompletely by following "clearing memory on Mate I or II" sectionlater in this chapter.

Before loading the configuration information from the PC to the Mate I or II, check thatthe "Mate to PC" serial cable assembly, labelled "Mate to PC,"is connected to the correctserial port of the PC. The cable assembly is provided with a 25 pin connector for the serialport, and a 25 to 9 pin adapter for use with a 9 pin serial port connection.

Attach the "Mate to RDC" cable to the Mate I or II and plug the Mate I or II into the "Mateto PC" serial cable assembly. Select Configure from the main menu of the CORRDATAsoftware, and then Load. Press the green ON switch on the Mate I or II. A short self testis made before the main menu appears.

WARNING! If a check sum error is indicated see chapter 9 MateI & II reprogramming utility.



> > > >

F1 F2 F3 F4

Press Setup (F4)


ConfigurationOptions

Mate RDC Route EXIT

> > > >

F1 F2 F3 F4

Press Mate (F1)

Mate Configuration

AUTO MANUAL CLRCONF CONF MEM EXIT

> > > >

F1 F2 F3 F4

Press Auto Configure (F1)

Connect Mate to PCPC must be running

CORRDATA SoftwareSTART EXIT

> > > >

F1 F2 F3 F4

Press START (F1) to commence the configuration information transfer from the PC to theMate I or II. During this process the Mate I or II will display the following message:


Configuring MatePlease Wait

ABORT

> > > >

F1 F2 F3 F4

On completion of the configuration the CORRDATA Mate will display the message:

Mate Configured

EXIT

> > > >

F1 F2 F3 F4

Press the red OFF key on the Mate I or II to switch off the unit, and disconnect it from theserial cable assembly to the PC. The Mate I or II is now configured ready to transfer theconfiguration information to any probe/RDC units. Now for the Mate II only, the clockmust be set on the Mate II before it can gather readings directly from probes withoutRDC's, as described in the next section. This is required so that the probe readings arecorrectly date and time stamped. For probes with RDC units, the controlling clock is inthe RDC and is set by the Mate I or II as described in the section "Configuration of theRDC" later in this chapter. Exit the CORRDATA PC software if required with the Esc keyand Quit from the main menu.

To configure the RDC units with the CORRDATA Mate see "Configuration of the RDC"later in this chapter.

Setting the Clock on the Mate II (Mate II only)

This is only required for monitoring of probes without RDC's since probes with RDC'shave their own clock in the RDC. This enables correct date and time stamping of therecorded probe data. To set the Mate II clock, proceed as follows:

1. Switch ON the Mate II.

2. After the self test screen clears, press: SetUp (F4); Mate (F1); MANUAL CONF(F1); SET TIME (F2); SET (F2). Enter the date and time in the format indicated:


YY 2 digits for yearMM 2 digits for month (1 to 12 months)DD 2 digits for date (note 2 = 02)HH 2 digits for hour (0 to 24 hours)MM 2 digits for minutesSS 2 digits for seconds

3. Press ENTER (F1) to synchronize the clock to the set time.

CAUTION: Check the Mate II clock before each use of theinstrument and adjust if necessary.

System Configuration from Mate I or II.

NOTE: Reading of this section of the chapter may be omitted if theMate I or II has been configured directly from the PC. See previoussection in this chapter.

It is generally easier to set up all the probe information on the PC and transfer it to theMate I or II, which in turn is used to program any RDC units on the system. However, itis also possible to configure the system entirely from the Mate I or II, and transfer thisinformation back to the PC later.

The Mate I or II may be programmed with the probe information for the whole system andthen taken to configure any RDC's on the system. Alternatively, the Mate can beconfigured one probe at a time and then used to configure any RDC's as you progress tovarious probes and RDC's. Before configuring the Mate, first check that the batteries havebeen installed. Switch on the Mate. After the self test screen clears, the main menu isdisplayed.



> > > >

F1 F2 F3 F4

Press SetUp (F4)



PhoneMate RDC Timer EXIT

> > > >

F1 F2 F3 F4

Select Configure Mate (F1) to program the probe data into the Mate II which will beused to configure any probes with RDC's. The following screen will be displayed:

Mate Configuration

AUTO MANUAL NEWCONF CONF PROBE EXIT

> > > >

F1 F2 F3 F4

NOTE: Auto configuration (F1) is used for configuration ofthe Mate I or II direct from the PC

NOTE: New probe (F3) appears on the Mate II only

For Mate I, press MANUAL CONF (F2). For Mate II, press MANUAL CONF (F2)and CONFIG ID (F1)

This will display:

Enter ID # > . . < 1-50

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

The system has a capacity of up to 50 probes per route. Each probe or probe with RDCis identified by its allocated ID number.


Enter the ID number from the keyboard, using CLR (F2) and BkSp (F3) if necessary,and press ENTER (F1) when complete. The screen then displays:

Enter Probe Tag> . . . . . . . . . . . . <

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

There is a provision for 12 alpha numeric probe identification or tag number characters.Enter the required designation and press ENTER (F1).

NOTE: Different cursors indicate either alpha or numericentries (See Figure 3.5). Use the alpha/numeric keyboardbutton to toggle between the modes as required.

NOTE: Additional descriptive probe information such ascompany name, location, etc., may only be added on the PCprogram, but not on the Mate II.

The next screen involves setting the frequency with which readings are taken if an RDCis used. On the RDC CORROSOMETER unit or RDC CORROTEMPCORROSOMETER unit the options are intervals of 5, 10, 15, and 30 minutes, or 1, 2,3, 4, 6, 8, 12 or 24 hours. For the RDC4-COT multiplexer unit this MUST NOT be setless than 15 minutes. For the RDC CORRATER unit or the RDC-CORROTEMPCORRATER unit the hourly settings are the same but the minute setting is limited to30 minutes due to the automatic cycle time of the unit required for the measurement.For choice of the most appropriate interval see "Choosing probe reading frequency",later in this chapter. For the Mate II, if the probe to be read does not have an RDCenter 0 and press ENTER (F1).

WARNING! Do not select a Mate I unit to read probessince the unit does not have this capability.

The first of the two selection screens shows the hourly selections.


RDC Time IntervalEnter ZERO if Probe(1-24) > . . < hours

ENTER CLR mins EXIT

> > > >

F1 F2 F3 F4

Either enter the number of hours required from the keyboard, using the CLR (F2) ifrequired and then press ENTER (F1), or press mins (F3) for selection of a minutesrange in which case the display will show the following for an RDCCORROSOMETER unit or an RDC CORROTEMP CORROSOMETER unit:

RDC Time IntervalEnter ZERO if Probe(5-30) > . . < minutes

ENTER CLR hours EXIT

> > > >

F1 F2 F3 F4

or the following for an RDC CORRATER unit or an RDC CORROTEMP CORRATERunit:

RDC Time Interval Enter ZERO if Probe (30) > . . < minutesENTER CLR hours EXIT

> > > >

F1 F2 F3 F4

For a minute selection, only the preset values will be used. Enter the required value andpress ENTER (F1).


WARNING! When using a Mate II for a probe without anRDC, make sure that 0 is entered for the time interval.Otherwise, the Mate II will be looking for an RDC at thisID number.

The next screen to appear is for selection of the element alloy of CORROSOMETERor CORROTEMP CORROSOMETER probes or electrode alloy of CORRATER orCORROTEMP CORRATER probes being monitored.

Enter Probe Alloy> . . . . . . . . <

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

Up to 8 alpha numeric characters may be used for the alloy description. This may bean abbreviated verbal description such as "C.Steel", "304 S.S.", or the 6 digit UNSmaterial code designation on the probe model or electrode set such as "K03005" or"S30400". Type in the description and press ENTER (F1). This will display aselection screen for the probe type.

Enter Probe Type > <(A thru F)

TYPEENTER CLR LIST EXIT

> > > >

F1 F2 F3 F4

To see a listing of the possible selections press TYPE LIST (F3).

A=WIRE E=CA B=TUBE F=CA-FLUSH C=STRIP D=CYLINDRICAL EXIT

> > > >

F1 F2 F3 F4

Press EXIT (F4) to return to the selection screen.


If a CORROSOMETER probe is selected (Type A, B, C, or D), a prompt will bedisplayed to check if the probe is a CORROTEMP CORROSOMETER probe.

Is this a CORROTEMPCORROSOMETER Probe?

NO YES

> > > >

F1 F2 F3 F4

Press NO (F1) or YES (F4) as appropriate.

CORROSOMETER and CORROTEMP CORROSOMETER probes are marked withboth their type A, B, C or D, and their probe span in "mils" (0.001 inch). For additionalreference the probe type and span are included in Figure 5.5.

CORROSOMETER OR CORROTEMP CORROSOMETER PROBE ELEMENT TYPE

SPAN

mils mm µm

Strip Loop S4 C 1.0 0.025 25

Flush Element S4*Atmospheric Element S4*Strip Loop S8Tube Loop T4

B

CB

2.0 0.051 51

Flush Element S8*Atmospheric Element S8*Tube Loop T8

B

B

4.0 0.102 102

Flush Element S10*Cylindrical Element T10

BD

5.0 0.127 127

Flush Element S20*Cylindrical Element T20Wire Loop Element W40

BDA

10.0 0.254 254

Wire Loop Element W45 A 11.25 0.285 286

Flush Element S40*Wire Loop Element W80

BA

20.0 0.508 508

Cylindrical Element T50 D 25.0 0.635 635

* Indicates corrosion occurs only from one side of element.

Figure 5.5 CORROSOMETER or CORROTEMP CORROSOMETER Probe Types and SpansCAUTION: CORROSOMETER Model 2500, 3500, or4500 probes are designated as a "cylindrical" element,


not a "tube" element which refers only to "tube loop"elements.

CORRATER probes either have standard projecting electrodes or flush electrodes. Theformer have a surface area of 5 cm2 per electrode and the latter have a surface area of0.5 cm2 per electrode. The letters E and F on the probe type screen have been added forthese two selections.

CAUTION: Different RDC units are required forCORROSOMETER and CORRATER probes asdesignated on the outside of the RDC boxes.CORROTEMP versions of these units must be used toread the temperature on CORROTEMP versions of theprobes.

If an incorrect selection between CORROSOMETER and CORRATER has been made,a subsequent error message will be displayed when the information is used to configurethe RDC unit.

Enter the appropriate probe type and press ENTER (F1). For the case of an RDCCORROSOMETER the following screen will appear:

Enter Probe Span> . . . . < Mils

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

The CORROSOMETER probe span is specified on the probe or may be obtained fromTable 5.5.

For the RDC CORRATER the corresponding screen requests input of the AlloyMultiplier, as the following screen depicts.

Enter Alloy Mult.>. . . . <

ENTER CLR BkSp EXIT

> > > >


F1 F2 F3 F4

Enter the appropriate span or multiplier and press ENTER (F1). The screen willconfirm the configuration information for this RDC is complete, and display the IDnumber and Tag.

WARNING! The span is always entered in mils even if thePC display is selected for millimeters or micrometers. Theprobe span is designated on the probe in mils.

Mate Configured for ID # . . Tag . . . . . . . . . . . .

EXIT

> > > >

F1 F2 F3 F4

Press EXIT (F4) to complete the entry for this RDC unit and return to the secondconfiguration options screen.

At this point, the information for this particular RDC has been completely loaded intothe Mate and is now ready for the next entry, or for loading directly to the RDC unit.

WARNING! Reconfiguring a probe ID number will causeloss of existing data on the Mate I or II. To avoid this, theprobe should be designated with a new ID. Editing of probeconfiguration may be done on the PC, but this may distortthe existing stored data.


Configuration of Probes with RDC's

Switch on the Mate I or II. After the self test screen clears, the main menu is displayed.



> > > >

F1 F2 F3 F4

Press SetUp (F4)


Mate RDC Route EXIT

> > > >

F1 F2 F3 F4

Select RDC (F2) to display the screen:

Enter ID # > . . < 1-50

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

Enter the number of the RDC unit to be configured using CLR (F2) or BkSp (F3) ifrequired.


Press ENTER (F1) to give the following screen:

RDC ConfigurationConnect Mate to RDC

DATE CONF TESTTIME RDC MODE EXIT

> > > >

F1 F2 F3 F4

When configuring an RDC for the first time, it is necessary to set its internal clock thatis used for date stamping the recorded probe values. The clock on the RDC unit itselfhas a battery backup so that it is unaffected by changing the main RDC batteries. Onceset the clock should not normally require resetting. In fact, resetting the clock willcause loss of existing data in the RDC.

NOTE: It is recommended that clock times are NOTcorrected for daylight savings times or summer time as thiscomplicates date and time stamping of corrosion data.

Attach the "Mate to RDC" cable to the Mate I or II, if not already connected, andremove the protective cover from the connector on the front of the RDC. Plug in thecable from the Mate I or II.

Before configuring the RDC, check that the unit has been set up and the batteriesconnected as described in the "Installation of RDC unit" in Chapter 3. PressDATE/TIME (F1) to display the following screen.

RDC Clock Set Tomm dd, yy hh:mm:ss

READ SET EXIT

> > > >

F1 F2 F3 F4

To check the existing time, if previously set, on the RDC, press READ (F1). To set orreset the time press SET (F2) to display the screen.


Set Date & TimeYYMMDDHHMMSS

> <ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

Type in the current year, month, date, hour (24 hour), minutes, and seconds, using theCLRCLR key (F2) and BkSpBkSp key (F3) as necessary. Once the entry is correct and theselected time is reached, press ENTERENTER (F1) to set in the selected time. The previousscreen reappears to confirm the entry.

RDC Clock Set Tomm dd, yy hh:mm:ss

READ SET EXIT

> > > >

F1 F2 F3 F4

This completes the clock entry and the RDC unit may now be configured for the probeparameters.

To exit the clock setting screen, press EXITEXIT (F4) and return to the screen.

RDC Configuration


> > > >

F1 F2 F3 F4

To prepare the Mate I or II for loading the configuration information into the RDCpress CONFCONF RDCRDC (F2). If the RDC to be configured is a CORROSOMETER unit thedisplay will be:


Mate connectedto RDC-CO

NEWSTART PROBE EXIT

> > > >

F1 F2 F3 F4

NOTE: If the unit to be configured is an RDC CORRATER,RDC-CA will appear on the screen instead of RDC-CO for anRDC CORROSOMETER.

To commence the configuration press SSTARTTART (F1). If the Mate I or II is loadingcorrectly, the following screens will be displayed.

Configuring RDCPlease Wait

> > > >

F1 F2 F3 F4

Followed by:

RDC # . .Configured

EXIT

> > > >

F1 F2 F3 F4

Pressing EXITEXIT (F4) will return the screen to the RDC configuration screen ready forthe next RDC unit.

If there should be any problems with the RDC unit, the probe, or its connections, oneof the following messages will appear:


WARNING MESSAGE CORRECTIVE ACTION

Mate Not Connected to RDC-CO C h e c k t h a t R D CCORROSOMETER unit is beingused, not a CORRATER unit.

Mate Not Connected to RDC-CA Check that the RDC CORRATERunit is being used, not aCORROSOMETER unit.

No Response from RDC . . . Check RDC unit batteries andconnections between Mate andRDC.

This RDC Already Configured . . . Check that correct RDC is beingconfigured, continue if RDCnumber is being changed.

WARNING! Reconfiguration of an RDC is possible butit will erase all previous data if the same RDC number isused. To avoid loss of data, collect the data and thenreconfigure the RDC with a new number.

Configuration of Probes Without RDC's (Mate II only)

Probes without an RDC do not need any further configuration, unlike probes withRDC's. It is recommended that probes without RDC's are physically labelled withtheir ID number. This should help prevent a wrong probe being read accidentally toa particular ID probe file. Probes with RDC's have the benefit of the RDCelectronics to prevent such an occurrence.

Choosing Probe Reading Frequency on RDC's

There are three factors to consider when deciding the most suitable probe readinginterval. These are:

1) The resolution required on the data.2) The type of RDC.3) The frequency of collecting probe data from the RDC.


CORROSOMETER and CORROTEMP Units

Reading IntervalBattery Life (days) With 14Ah Battery Pack

Single Channel RDC4

5 mins 39.5 ---

10 mins 68.6 ---

15 mins 90.9 30.8

30 mins 134.6 55.1

1 hour 177.2 90.9

2 hours 210.5 134.6

3 hours 224.6 160.3

4 hours 232.4 177.2

6 hours 240.7 198.1

8 hours 245.1 210.5

12 hours 249.6 224.6

24 hours 254.4 240.7

Figure 5.6 Battery Life with RDC-CORROSOMETER and CORROTEMP

NOTE: Battery life values are based on a 20% safetymargin on nominal battery capacities at 25oC. Batterycapacity is reduced approximately 15% at -40oF (-40oC) andapproximately 40% at 160oF (70oC).

In general, the greater the number of readings taken the better is the resolution oncorrosion events. This must be balanced against battery life, battery costs and thefrequency with which data will be collected.


CORRATER

ReadingInterval

Battery Life (days) With 14 Ah Battery Pack

Minimum Typical Maximum

20 minute cycletime

5 minute cycletime

2 minute cycletime

30 mins 16.4 55.1 104.5

1 hour 30.8 90.9 148.9

2 hour 55.1 134.6 189.2

3 hour 74.7 160.3 207.9

4 hour 90.9 177.2 218.8

6 hour 116.0 198.1 230.8

8 hour 134.6 210.5 237.3

12 hour 160.3 224.6 244.2

24 hour 198.1 240.7 251.5

Figure 5.7 Battery Life with RDC-CORRATER

Using the tables shown in Figure 5.7 and 5.8 the reading intervals should be chosenso that the battery pack will last at least through the time period between collectionof data from the RDC.

Clearing Memory on CORRDATA Mate I or II

Normally it will not be necessary to clear the memory on the Mate I or II unlessextraneous entries have been made, for example, when initially experimenting withthe system. Alternatively, if the equipment is to be transferred to a new location, oris used on more than one data collection route then it is recommended to clear thememory on the Mate to avoid conflict or the addition of other probe data to the probelist. To clear the memory of the Mate I or II it is necessary to enter the Configuremode. From the initial screen,




> > > >

F1 F2 F3 F4

For the Mate I press SetUpSetUp (F4) and CLRMEMCLRMEM (F3). For the Mate II press SetUpSetUp(F4), MateMate (F1), MMANUALANUAL CONFCONF (F2), and CLRCLR MEMMEM (F3). On either Mate Ior II the following screen will appear:

CLEARING MEMORYPlease Wait

> > > >

F1 F2 F3 F4

This will take approximately 30 seconds to clear, indicating that the memory is nowcleared.

Clearing Memory on RDC

Normally this will not be necessary, since reconfiguration of the RDC automaticallyclears the memory of any previous data. The memory back-up battery can be shutoff (See item 5, fig 3.2) to clear memory, after the main battery has also beendisconnected.

49

Chapter 6Normal Operating Procedures

Once the system has been configured as described in Section 5, data may be collected from probesand RDC's at any time for transfer to the PC. Probes with RDC's normally will be left toautomatically collect data, and later at some convenient time, the data may be gathered. Theadvantage of probes with RDC's is the improved resolution of corrosion dynamics due to theincreased reading frequency.

Collecting Stored Data from RDC's

With the Mate I or II configured, proceed to the first Probe/RDC location to beinterrogated. Connect the "Mate to RDC" cable and switch on the Mate I or II. After theself test screen clears, the main menu is displayed.



> > > >

F1 F2 F3 F4

The following screen will appear. Press Read (F1) which displays the screen:

What to Read?

PROBE RDC EXIT

> > > >

F1 F2 F3 F4

For an RDC press RDCRDC (F3) to display:


Connect Mate to RDC

START EXIT

> > > >

F1 F2 F3 F4

Remove the protective cover on the connector of the front of the RDC unit and connect thecable from the Mate I or II.

Press Start (F1).

The following screen will show during initial interrogation and data collection by the MateI or II.

Interrogating RDCPlease Wait

ABORT

> > > >

F1 F2 F3 F4

If the following message appears check the connection between the Mate and RDC and trythe reading again. If the same message appears, check the RDC batteries as described laterin this chapter.

WARNING!No Response from RDC

Try again in 30 sec.EXIT

> > > >

F1 F2 F3 F4

Once data collection commences the following screen will appear briefly.

Chapter 6 Normal Operating Procedures 51

Collecting DataPlease Wait

ABORT

> > > >

F1 F2 F3 F4

This latter process takes only a second or two depending on the amount of data to transferso that they may barely be visible unless there is a problem with either process.

On completion of the data collection, the screen will display the identification of the RDCfrom which data has been collected as follows:

Data Collected from RDC # . . Tag . . . . . . . . . . . .

EXIT

> > > >

F1 F2 F3 F4

If for any reason there is a problem with data collection, one of several messages mayappear.



No response from RDCTry again in 30 sec.(Repeating after two tries)

Check RDC unit batteries

RDC not configured Reconfigure the RDC

Probe life exceeded(CORROSOMETER or CORROTEMPCORROSOMETER Probe Only)

Data has been collected but probe isnearing the end of its life. A replacementshould be installed promptly.

Probe over 80% used(CORROSOMETER or CORROTEMPCORROSOMETER Probe Only)

Order a replacement probe.

Data collection is complete and pressing EXIT (F4) returns to the initial screen shown atthe start of this section ready for the next RDC unit.

Remove the "Mate to RDC" cable from the RDC, replace the protective cover on the RDCunit connector and switch off the Mate I or II.

Collecting Data from Probes without RDC's (Mate II only)

With the Mate II configured, proceed to the first probe location without an RDC. Attachthe "CORROSOMETER" cable to the Mate II if the probe is a CORROSOMETER or aCORROTEMP probe. Attach the "CORRATER" cable to the Mate II if the probe is aCORRATER probe. Switch on the Mate II. After the self test screen clears, the mainmenu is displayed.



> > > >

F1 F2 F3 F4

Press Read (F1) which displays the screen:


What to Read?

PROBE MODE RDC EXIT

> > > >

F1 F2 F3 F4

Select PROBE (F1) to display:

Read CA or CO Probeby

ID TAG EXIT

> > > >

F1 F2 F3 F4

To select the probe by ID number, select ID (F1); to select the probe by TAG number,select TAG (F2)

NOTE: Search by ID is more rapid than search by TAG.

Enter the appropriate ID or TAG for the selected probe, and press ENTER (F1). For aCORROSOMETER or CORROTEMP CORROSOMETER probe the screen will display:

Connect Mate to CORROSOMETER PROBE

ID: . . . . . . . . . . . .START EXIT

> > > >

F1 F2 F3 F4

For a CORRATER probe the screen will display:


Connect Mate to CORRATER PROBE

ID: . . . . . . . . . .START EXIT

> > > >

F1 F2 F3 F4

Check carefully that the correct probe to be monitored has been selected and press START(F1). The screen will indicate that the probe is being read as it occurs. This time will varyin length according to the probe being monitored. When complete, the probe reading willbe displayed as follows for a CORROSOMETER probe:

CO PROBE READINGS Div: . . . Check: . . .

EXIT

> > > >

F1 F2 F3 F4

or as follows for a CORROTEMP CORROSOMETER probe:

CO PROBE READINGS Div: . . . Check: . . . Temp: . . . degs C

EXIT

> > > >

F1 F2 F3 F4

or as follows for a CORRATER probe:


CA PROBE READINGS RATE: . . . IMBALANCE: . . .

EXIT

> > > >

F1 F2 F3 F4

The readings with their time and date are automatically recorded by the Mate II, each time theprobe is read. When readings are complete, switch OFF the Mate II and proceed to the next probeto be monitored.

Displaying Probe Data

After collecting probe data, it is possible to review the last reading on the Mate I or II. Infact it is possible to view the last reading of any location, where data has been collected onthe Mate I or II.

To view the data, switch on the Mate I or II. After the self test screen clears, the mainmenu is displayed.



> > > >

F1 F2 F3 F4

Press Disp (F2) to show the screen.

Display Data on Mateby

CURRPROBE ID TAG EXIT

> > > >

F1 F2 F3 F4

To display the last recorded reading from the most recently read probe, press CURRPROBE (F1). To select the reading from a different probe, press ID (F2) and the displaywill request the ID number.


Enter ID (1-50)> . . <

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

Type in the ID number and press ENTER (F1).

Alternatively, to select a probe by it's tag, press TAG (F3) and the display will request thetag number:

Enter Probe Tag>. . . . . . . .<

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

Type in the tag number including trailing spaces to fill the field and press ENTER (F1).This search is not as fast as for the ID number. During the search the following screen isdisplayed:

SEARCHING FOR PROBEPlease Wait

EXIT

> > > >

F1 F2 F3 F4

After completing the probe search, data is displayed in the following manner:

Two screens are used to display data which vary slightly between standard andCORROTEMP units. For example, reading a RDC CORROSOMETER the first screenwill display:


ID: . . . . . . . . . . Type . . . Span: . . . . . Div: . . . Chk: . . . (. . .)MORE EXIT

> > > >

F1 F2 F3 F4

"Div" is the probe reading, where 0 to 1,000 is the useful probe life or span. "Check" teststhe integrity of the reference element, and should be within ± 25 of its initial value givenin the parentheses.

The second screen, viewed by pressing MORE (F1) will display:

. . . . Readings @ . . hrs Alloy: . . . . . . . .

EXIT

> > > >

F1 F2 F3 F4

For CORROTEMP versions the temperature is added to the second screen as follows:

. . . . Readings @ . . time Alloy: . . . . . . . . Temp:. . . . Deg C

EXIT

> > > >

F1 F2 F3 F4

On probes with RDC's, the number and frequency of readings is indicated. On probeswithout RDC's (Mate II only), the reading frequency is set to 0. The number of readingsis indicated to a maximum number of 2048 for CORROSOMETER RDC's, 1024 forCORROTEMP CORROSOMETER RDC's, CORRATER RDC's, and 512 forCORROTEMP CORRATER RDC's. For the Mate II reading probes directly the maximumnumber of stored readings is 256. At the maximum number of readings the oldest readingwill be discarded whenever a new reading is added.

NOTE: During the RECEIVE operation the new data and the olddata will be merged in the current file and the old data will beconverted to a backup file automatically with a .BAK extension.


To return to the main menu screen press EXIT (F4). The rest of the collected probereadings must be viewed on the PC where the data is shown graphically.

Replacing a CORROSOMETER or CORROTEMPCORROSOMETER Probe of the same type on an RDC

The need for a replacement probe is indicated on the Mate I or II when taking a reading,and also on the probe list of the CORRDATA Software. A warning to order or replace aprobe "soon" is given at over 80% of probe life, and to replace "now" at over 95% of probelife.

When replacing a CORROSOMETER or CORROTEMP CORROSOMETER probe withanother one of the same type, it is necessary for the check reading value of the new probeto be reset so that any subsequent deterioration can be tested. This is the purpose of thefollowing sequence. If this is not done and the probe is simply replaced, the differencebetween the check reading of the new probe and the old probe may be sufficient to triggerthe check reading alarm signal.

On a CORROSOMETER or CORROTEMP CORROSOMETER probe with an RDC, theMate I or II will indicate the end of probe life when data is collected from the RDC. Endof useful probe life corresponds to half the probe element thickness. Similarly if there hasbeen a series of faulty check readings this will also be indicated so that replacement canbe made.

NOTE: Even if faulty check readings have occurred, probe data willstill be collected. The graphical display on the PC however, willindicate a faulty check by a half thickness graph line.

After the collection of the probe data indicating that the probe needs replacement, plug theMate I or II cable into the RDC before disconnecting the probe. This suspends probe datacollection and avoids spurious readings while the RDC and probe are disconnected.Unscrew the probe cable connector and carefully replace the probe with the new probe.Make sure the probe and plug connections are clean. Tighten the connector clamp ringfirmly to ensure a good connection.

On the Mate I or II, select SET UP (F1) from the main menu.



> > > >


F1 F2 F3 F4

Press RDC (F2)

Enter ID # > . . < 1-50

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

Enter the ID number and press ENTER (F1).

RDC Configuration


> > > >

F1 F2 F3 F4

Select CONF RDC (F2).

Connect Mateto RDC-CO

SET NEWSTART MUX PROBE EXIT

> > > >

F1 F2 F3 F4

Select NEW PROBE (F3), and EXIT (F4) twice to return to the main menu. Datacollection of the new probe will commence, taking account of the new initial checkreading.

NOTE: When changing out the CORROSOMETER orCORROTEMP CORROSOMETER probe with the same type, it is onlynecessary to reconfigure the RDC for the new check reading. Noreconfiguration is required of the PC or the Mate I or II since the sameprobe type is used. If a different probe type is installed follow theprocedure in the next section of this chapter.


Replacing a CORROSOMETER or CORROTEMPCORROSOMETER Probe of a different type on an RDC

When replacing a CORROSOMETER or CORROTEMP CORROSOMETER probe witha different probe type or span, the simplest method is to first collect the data beforedisconnecting the old probe. Secondly, reconfigure the Mate I or II and RDC with a newID number for this location by entering the necessary probe parameters for the new probe.

After replacement and re-connection of the new probe, the RDC must be configured for thenew ID number. If the new ID number has already been entered on the PC (see "SystemConfiguration from the PC in Chapter 5 ) and the Mate I or II configured accordingly, thenproceed with configuration of the RDC as described in "Configuration of probes withRDC's" in Chapter 5. If the PC and Mate I or II have not been configured for a new IDnumber, follow "System Configuration from Mate I or II" in Chapter 5. The transfer of theinformation to the PC will be done during the Receive operation and automatically enteredinto the probe list.

Replacing a CORROSOMETER or CORROTEMPCORROSOMETER Probe of the same type without an RDC(Mate II only)

It is only necessary to reset the initial check reading when changing out a probe of the sametype, so that any subsequent check alarm will be correctly detected. After collecting theold probe data, switch ON the Mate II, select SetUp (F4), and Mate (F1) to display:

Mate Configuration

AUTO MANUAL NEWCONF CONF PROBE EXIT

> > > >

F1 F2 F3 F4

Press NEW PROBE (F3) and Select the ID of the probe being changed and press Enter(F1) to zero the initial check reading and adjust the installed date. Replace the old probeif not already done so. Press EXIT (F4) twice to get to opening menu screen. Then readthe new probe in the normal way. This will then generate a new initial check (which willdisplay in the parentheses) and will change the installed date. The probe list on the PC willindicate the new installation date.


Replacing CORRATER or CORROTEMP CORRATERProbe Electrodes

A CORRATER or CORROTEMP CORRATER probe may be changed out withoutneeding to reconfigure the Mate, RDC, or PC, provided the probe alloy, or probe type(either flush or standard) has not been changed. If you specifically wish to record thechange-out time, follow the same procedure as for the CORROSOMETER probe.

With CORRATER or CORROTEMP CORRATER probes, it is not apparent from thereading when electrodes should be changed as it is with the CORROSOMETER probes,which indicate when their useful life has been consumed. Consequently, there will be noautomatic message appearing on the Mate I or II to warn of the need for an electrodechange-out.

The following are the indications to be watched:

Indication Action

1) An abnormal increase in corrosion rate. 1) Inspect probe for bridging ofelectrodes, particularly bymaterial at the base ofelectrodes. - Clean asnecessary.

2) An abnormal falling off or decrease in 2a) Inspect probe electrodes. corrosion rate particularly in high Initial diameter 3/16"corrosion rates (over 20 mpy). (0.188", 4.78mm). Replace

when diameter is down to5/32" (0.156" 3.96mm).

2b) Inspect probe electrodes forany non-conductive depositsreducing effective electrodesarea, such as oil film,paraffins. Replace electrodes.

CORRATER or CORROTEMP CORRATER probes require that the electrodes are alwaysfully submerged in a sufficiently conductive electrolyte. Consequently, the probes shouldNOT be positioned in an environment where:

1) Electrodes are in an air pocket or cavity. 2) Non-conductive deposits form on the electrodes, to reduce their effective area

(corrosion rate measurement depends directly on the fixed surface area of theelectrodes).

For further details on the CORRATER theory see Appendix B.


In general, when using CORRATER or CORROTEMP CORRATER probes over anextended period it is advisable to remove and inspect the probe at intervals, initially eachtwo weeks depending on the contaminants in the system, to check if cleaning the probesignificantly reduces the corrosion rate. The results of these tests will determine if thisfrequency of cleaning is necessary, or whether a longer period may be allowed.

In a number of instances, it may be useful to use the CORRATER or CORROTEMPCORRATER probe electrodes as weight loss coupons against which to correlate thisintegrated corrosion rate against the probe. This removes the question that is often askedabout how to compare CORRATER probe readings with coupons (for more details seeRCS Application Notes AN101 and AN102).

If the probe electrode alloy or probe type is changed, then the RDC must be reconfigured.In fact if the probe alloy is changed it will be preferable to reallocate an ID number toavoid two different alloy corrosion rates appearing on the same graph of the PC. Re-configuring an RDC is the same as initial configuration which is described in Chapter 5.

RDC Battery Check and Replacement

A main battery test switch is provided on the RDC, by a small push button next to thebattery connector onto the circuit board (See Figure 3.2). Press the button to test. If thebattery is in good condition the red indicator next to the push button will illuminate. If thered indicator does not illuminate or the batteries are to be replaced as a routine matterproceed as follows:

1) Disconnect battery connector from circuit board by squeezing the clips atthe sides of the connector (4) and pulling the connector.

2) Remove the battery holding support and replace the battery.

3) Replace the battery connector and push the test button (2) to check the newbattery is operating correctly, by illumination of the red indicator (3).

4) Do not switch off the back up battery during this main battery replacement.

WARNING! Near the very end of battery life there may be amarginal period where the LED will light but the battery will notperform under full load conditions. This period is normally only afew hours, but may be affected by ambient temperature changes.

Transferring Collected Data to PC

Once a set of data has been collected by the Mate I or II, it is a simple matter to transfer theinformation to the PC.

Chapter 6 Normal Operating Procedures 63First, start the CORRDATA software program from your shell or menu, or from the DOSprompt by changing to the CORRDATA directory and typing CD2.

To clear the initial identification screen, press ENTER and the main menu will appear.

Figure 6.1 CORRDATA PC Software Main Menu

Select Receive on the main menu. The PC will indicate when it is "Ready to Receive".Attach the "Mate to RDC" cable to the Mate II.

Switch ON the Mate II.



> > > >

F1 F2 F3 F4

Select Dump (F3)


Connect Mate to PCPC must be running

CORRDATA SoftwareSTART EXIT

> > > >

F1 F2 F3 F4

Connect the Mate II to the serial port of the PC with the cable assembly supplied, using the25 pin connector or the 25 to 9 pin adapter as necessary.

WARNING! Check that the cable is connected to the correctCOM1 or COM2 port corresponding to the version of theCORRDATA software installed (See Chapter 3 "CORRDATA PCSoftware").

To commence data transfer press START (F1). Warnings will show on the Mate II screenif no communication occurs, or if any bad communication is detected.

WARNING ACTION

No response from PC Check connections.

Check connections andverify that correct serialport is being used.

Error while dumping data. TRY AGAIN.

Bad communication. Repeat the transfer operation.

During copying of the data to the PC, the following screen will appear on the Mate II,showing the data copying by ID number.

Dumping Data to PCPlease WaitRDC # . .

ABORT

> > > >

F1 F2 F3 F4

The PC will show the file copying as it occurs, and the subsequent merging of the new datainto the existing data files. If any configuration mismatches are detected between the Mate

Chapter 6 Normal Operating Procedures 65I or II and the PC these will be displayed for resolution by a series of options, as describedin the next section of this chapter.

On completion of data transfer, the Mate I or II will revert to its normal main menu. At thetime of merging the new data into the existing files in the CORRDATA directory, backupfiles of the previous data are also created with a .BAK extension in the same directory.The Mate I or II also retains the new data files after the copying process, thereby acting asa new data backup file. Any new files that have been set up on the Mate I or II in the fieldwill automatically be added to the probe list, provided they do not conflict with any otherfile entries.

Resolving any Data Merging Conflicts

Normally conflicts with data merging on the PC are unlikely to occur, but there are anumber of alternatives to select if they do arise.

Probe monitoring information on the CORRDATA system can be stored at up to threelocations. These are the PC, the Mate I or II, and the RDC. Since the Mate I or II can beprogrammed independently of the PC, differences can be generated between the Mate I orII and the PC. Such changes could affect the accuracy of the data in some instances ifunregulated merging were permitted.

WARNING! If an RDC unit is reconfigured by a Mate I or II, thepreviously stored data on that RDC will be deleted. If an ID on theMate I or II entry is reconfigured by the PC, that data in the Matewill be deleted.

If an RDC is to be reconfigured because of a probe type change, the data from the RDCshould first be collected, and then the RDC should be reconfigured using a new ID number(See "Replacing probes" earlier in this chapter).

When the PC attempts to merge data from the Mate II following the Receive operation, anydiscrepancy in the key configuration fields will be displayed in the following manner.


Figure 6.2 Resolving Conflicts during RECEIVE operation

Of the key configuration fields, only probe type, probe span, probe multiplier or timeinterval actually can change the basic corrosion data. Discrepancies in these fields will notallow merging, even if F2=MERGE is pressed. Discrepancies in the other configurationfields permit F2=MERGE, since these fields are only descriptive. In this case the existingPC fields will be retained.

F3=OVERWRITE will cause the existing file on the PC to be overwritten by the newconfiguration and data from the Mate II, deleting the previous data on the PC.

F4=RENAME enables the configuration and data on the Mate II to be saved as a separatefile leaving the existing one un-disturbed. If this option is selected, a box will be displayedfor the pathname (i.e. directory and filename) where the data is to be saved. The currentCORRDATA directory may be used, provided a different filename is used from any of theexisting files.

F5=DELETE deletes the file received from the mate, and leaves the existing file on the PCintact.

Archiving and Retrieving Old Data Files

The basic CORRDATA software provides for saving of files one at a time for archivingpurposes, and for retrieving files for viewing one at a time. Any files saved areautomatically given the extension .SAV to avoid any overwriting even if the files are savedto the CORRDATA directory. For archiving, sub-directories should be set up for therequired time periods (such as CD_MAR94) for storage of data at that time. Each file willstore up to 9,000 data points.

To save the current data to a sub-directory, first create the sub-directory in DOS at therequired location before entering the CORRDATA program. Start the CORRDATAprogram and select Save, to select the directory as shown. Pathname is initially defaultedto the current directory. Press Tab to display files in this directory.


Figure 6.3 CORRDATA PC Software File Saving

Use the 88 or 99 keys to make the required selection, and press the Tab key. This willdisplay the selected file into the "Save to" box with the cursor and a .SAV file extension,and leave a gray highlight bar at the selected probe in the file box above. Modify thepathname as necessary for the destination sub-directory (such as c:\CORRDATA\MAR94\RDC_11.SAV) already created in DOS. Press INSERT KEY to change to insert mode(shown by thin cursor, typeover shown by thick cursor). Press Enter to save the file , oruse Esc to leave this screen without saving.

NOTE: In the CORRDATA basic software, data files can only besaved to an archive directory one at a time.

Archived data files may also be retrieved for the full viewing and analysis capability of theCORRDATA program via the Display menu. Only one data file at a time may be viewedfrom the archive files in the basic software. Exiting the View or Range on the Display sub-menu to List or back to the main menu will automatically cancel the archived data fileselection. However range zooming and rate calculations on graphs are fully operationalon the retrieved file before exiting as described.

NOTE: A retrieved file is never added to the probe list in the currentCORRDATA program directory. This may only be achieved bychanging the filename outside the program to an unused ID number,installing the file in the CORRDATA program directory, and thenselecting this ID number through the NEW entry screen in theConfigure mode, and View in the display mode.


To Retrieve an archived file, select File from the main menu, and Retrieve from the sub-menu. The box that appears will show a pathname box with a cursor present, and a blankfile box. Modify the pathname as required to select the required directory and files usingwildcards and extensions as convenient to simplify the displayed list of files (example:C:\CORRDATA\CD_MAR94\*.SAV). This will produce a display similar to thefollowing.

Figure 6.4 CORRDATA PC Software File Retrieval

Press Tab to switch from the pathname box to a highlight bar in the file list box. Use the88 or 99 arrows to select the required RDC and press Enter. Press Display and View todisplay the graph. The graph may be zoomed as required, and corrosion rates displayedwith the cursor keys and Enter. To return to the current operating probe list, press Esc andList.

71

Chapter 7Corrosion Data Analysis

In the basic software package the corrosion data may be viewed one probe at a time in a graphicalformat which is generally the most useful to interpret corrosion events and trends.

Once data has been collected by the Mate I or II and transferred to the PC, the CORRDATA softwareprogram is ready to display that data.

It should be made clear here the fundamental difference between CORROSOMETER or andCORRATER probes. CORROSOMETER probes directly measure metal loss whereas CORRATERprobes directly measure corrosion rate. A single reading from a CORRATER prove gives the corrosionrate at that time. For a CORROSOMETER probe the metal loss over some finite period of time mustbe used to calculate corrosion rate.

NOTE: CORROTEMP CORROSOMETER probes areCORROSOMETER probes with a temperature measurement sensoradded, and CORROTEMP CORRATER probes are CORRATER probeswith a temperature sensor added.

In a sense the CORROSOMETER measurement can be likened to an automobile odometer ormileometer, where the CORRATER measurement can be likened to the speedometer.

For a CORROSOMETER probe, the "current corrosion rate" must actually be calculated on the metalloss occurring over some finite period of time, normally ranging from a few hours to a few days. Hencefor the CORROSOMETER probe corrosion rate is always a calculated number.

The Mate II collects corrosion data both from probes with RDC's, and directly from probes withoutRDC's. The advantage of RDC's is to provide much higher frequency of measurements and a muchimproved resolution of corrosion dynamics. The graphical display of RDC generated data is similarto data generated by individual probe readings, in that straight lines are drawn between the individualreadings. The only difference between the two types of data is that data points from direct probemeasurements are identified with small circles around each point.


Displaying CORROSOMETER and CORROTEMPCORROSOMETER Metal Loss Data

To display any of the current CORROSOMETER or CORROTEMP CORROSOMETER metalloss data, it is first necessary to select the sub-directory containing the CORRDATA programand type the command CD2 .

NOTE: Selection of the sub-directory CORRDATA and issuing of thecommand CD2 may be incorporated into your PC shell, menu, orWindows to give direct entry to the CORRDATA program.

Select Display from the main menu and then List from the sub-menu to display the currentprobe list.

Figure 7.1 Probe Display Selection

Chapter 7 Corrosion Data Analysis 73

CAUTION: Metal Loss versus time graphs are available forCORROSOMETER and CORROTEMP CORROSOMETERprobes, and only Corrosion Rate versus time graphs areavailable for CORRATER. However, Corrosion Rate forCORROSOMETER and CORROTEMP CORROSOMETERprobes may be computed over any particular period by use ofthe cursors on the graph (see the next section of thischapter).

A probe list summary of all the probes on the system will be added to the screen. To select therequired CORROSOMETER or CORROTEMP CORROSOMETER probes use the cursorkeys. Press Esc to return to the display sub-menu, and View to display a metal loss againsttime graph such as the following.

Figure 7.2 CORROSOMETER Probe Metal Loss Graph from an RDC

NOTE: If a probe has not been selected from the probe list or no probedata has been collected for the selected probe or only a single data pointhas been collected, a blank graph will briefly appear and then disappearwhen VIEW is selected.

Initially the y-axis of the graph is scaled to the full span of the probe life e.g. a T10 probe hasa 5 mil span, a T20 has a 10 mil span (see Table 5.1) and the x-axis has a time periodcorresponding to the period of data collected, up to a maximum of 9,000 readings dependingon the type of data. The last recorded probe data is on the right hand side of the screen.


NOTE: Number of readings maximun per file is as follows:

RDC-CO - 9048 data pointsRDC-CA - 4524 data pointsRDC-COT & RDC-CAT - 2262 data pointsDirect CO, COT, CA or CAT probes - 1131 data points

Once the file is filled to its maximun size the oldest data is discarded as new data is added. Ifdata older than this is to be kept, this may be done by saving the data to a separate file atintervals as described in Chapter 6 "Archiving and Retrieving Old Data Files".

On the X-axis the scale is identified in days. The date of the last recorded reading is shown onthe bottom of the graph (for example, on the above graph the last data was recorded on April2, 1992, where April 2 is from 16.0 to 17.0. The first day is from 0.0 to 1.0)

Editing and Analyzing CORROSOMETER Probe Graphs

Select the required portion of the graph with the vertical cursors. To adjust the cursor for thispurpose, use the 66 or 77 arrow keys to move the cursor, and the Space bar to switch betweenthe two cursors.

NOTE: Initially the cursor lines are on the sides of the graph and maynot be readily visible. The selected cursor at entry is the left hand line.

Once the desired selection has been made press Enter. The corrosion rate will be calculatedand displayed along with the start and finish dates corresponding to the cursor positions. Thecorrosion rate is determined by Linear Regression (i.e. the slope of the best straight line throughthe selected data)

WARNING! No corrosion rates or dates are displayed in this boxuntil one or other of the cursor lines has been moved, and the Enterkey pressed.


Figure 7.3 CORROSOMETER Metal Loss Graph from an RDC with Rate and Date Display

To zoom in on the corrosion data graph press Esc to return to the display sub-menu and selectRanges. Choose either the X-Select or Y-Select as required. If the Y-Select is chosen thegraph will reappear with two horizontal cursors lines at the top and bottom of the graph.

Use the 88 or 99 keys to move the cursor lines, and the Space bar to toggle between the twocursors as shown in Figure 7.4. When you are satisfied with the selection press Esc.

If you also wish to zoom in on the X-axis choose the X-Select. The graph will reappear withthe X range zoomed in. Use the 7 or 6 keys to move the cursor lines and the Space bar totoggle between cursors, and to select the required range. Press Esc twice and View to displaythe zoomed in graph.


Figure 7.4 CORROSOMETER Probe — Selecting Y-range

Re-entering Ranges on the display sub-menu will cause the X and Y axes to return to the fullyzoomed out ranges ready for the next selection.

Figure 7.5 CORROSOMETER Probe — Selecting X-Range

The metal loss graph line will normally be thick for most or all of the graph (2 pixels wide) butmay be thinner near the end of probe life (1 pixel). This is determined by the condition of theCORROSOMETER or CORROTEMP CORROSOMETER probe check reading. The probe


check reading should remain constant within ± 2.5%. If it does not, it indicates possibledamage to the probe's internal reference element. A bad check reading condition is recordedalong with the metal loss and causes the graph to change to a thin line.

The thin graph line indicates that this part of the metal loss graph may be suspect, and that theprobe should be replaced. Corrosion occurring on the reference element will generally causea decrease in the recorded metal loss.

Displaying CORRATER and CORROTEMP CORRATERCorrosion Rate Data

The method for selection and display is very similar to that of the CORROSOMETER probes.

From the main menu of the CORRDATA software select Display and then List from the sub-menu.

The probe list summary will be added to the screen and the required CORRATER orCORROTEMP CORRATER probe may be selected with the cursor keys followed by the Enterkey. Press Esc to return to the display sub-menu, and View to display a corrosion rate versustime graph such as the following:

Figure 7.6 CORRATER Probe GraphInitially the Y-axis is set to 50 mpy (1.25 mmpy, or 1250 µmpy) or 640 mpy (16.25mmpy or16,250 µmpy) depending on the values in the range. The x-axis has a time periodcorresponding to the period of data collected, up to the maximum of data points. The lastrecorded probe data is on the right hand side of the screen.


Data older than the maximum file size is discarded as new data is added. If data older than thisperiod is to be kept, this may be done by saving the data to a separate file at intervals asdescribed in Chapter 6 "Archiving and Retrieving Old Data Files".

On the X-axis the scale is identified in days. The date of the last recorded reading is shown onthe bottom of the graph. (For example, on the above graph the last data was recorded on April2, 1992, where April 2 is from 15.0 to 16.0. The first day is from 0.0 to 1.0)

Editing and Analyzing CORRATER Probe Graphs

From the graph it is very simple to identify high corrosion rates and the corresponding periodover which they occurred. The average corrosion rate over any period of the graph can bedisplayed at the bottom of the graph, and is the arithmetic mean of the readings selected. Thestart and finish dates corresponding to the cursors are also displayed.

WARNING! No average corrosion rate is displayed in this boxuntil one or other of the cursor lines has been moved and the Enterkey pressed.

To adjust the cursors for this purpose, use the 7 and 6 keys to move the cursor, and the Spacebar to switch between the two cursors. Once the desired selection has been made press Enter.The average corrosion rate will be calculated and displayed, along with the start and finishdates.

NOTE: Initially the cursor lines are at the left and right sides of thegraph and may not be readily visible. The selected cursor at entry is theleft hand line.

In addition to corrosion rate measurement the CORRATER system also makes a form of"Electrochemical Noise" measurement, which is a measure of the current flow between twonominally identical electrodes. Rohrback Cosasco has been using the measurement for manyyears in its CORRATER range under the name of pitting or imbalance. The measurement isstill qualitative rather than quantitative. However, pitting systems will generate current andpotential noise between nominally identical electrodes as a result of the non-uniformity of suchsystems. The result in pitting environments is a general increase in the current between theelectrodes and an increasingly erratic signal (for further information see Appendix B).

To obtain the imbalance or pitting values on the corrosion rate graph press "I" on the keyboardto toggle the readings back and forth. The ranges for Imbalance are separately adjusted in thesame manner as the main corrosion rate displays.


For convenience of comparison, the x-axis zoom automatically applies to both the corrosionrate and imbalance graphs. The y-axes are independent.

NOTE: Only one graph of corrosion rate or imbalance may bezoomed in on at a time.

Imbalance readings have no units corresponding to a pitting rate. The scaling of the units hasbeen arranged such that imbalance readings in excess of the corrosion rate value indicate ahigher probability of pitting. Lower values than the corrosion rate value indicate lowprobability of pitting.

It is also possible to zoom in on the graph both on the X-axis and the Y-axis. To do this, pressthe Esc to return to the display sub-menu and select Ranges. Then choose either the X-Selector Y-Select. If the Y-Select is chosen the graph reappears with two horizontal cursor lines atthe top and bottom of the graph.

Use the 88 or 99 keys to move the cursor lines, and the Space bar to toggle between the twopoints as shown in Figure 7.7. When you are satisfied with the selection press Esc. Eitherpress X-Select for further X range zooming, or press Esc and View to display the graph. Aftera few seconds the graph will reappear to display the zoomed in range.

Figure 7.7 CORRATER Probe Selecting Y-Range

Automatic determination of average corrosion rate is made by movement of the vertical cursorlines on the graph in the View mode, and pressing Enter. This is particularly useful if


comparison is required with weight loss on the electrodes or coupons over a particular period.

With an imbalance graph, a similar average imbalance value may be automatically read off thegraph.

Displaying Temperature on CORROTEMP Probe Versions

CORROTEMP probes have an added temperature sensing device.

CAUTION: A CORROTEMP CORROSOMETER RDC willread CORROSOMETER or CORROTEMP probes but aCORROSOMETER RDC will only read CORROSOMETERprobes.

To display the temperature graph on a CORROTEMP CORROSOMETER probe, first selectthe probe from the probe List in the normal way. Use the "T" key to toggle between graphsof metal loss and temperature. The temperature graph may be zoomed in the same way as themetal loss graph. For convenience, the x-axes of the two graphs zoom together to display thesame time period of data. The y-axes of the two graphs are independent.

NOTE: Only one graph of metal loss or temperature may be zoomedin on at a time.

The average temperature measurement may be computed automatically over a period of timeby using the vertical cursors to select the desired time span and pressing Enter.

On CORROTEMP CORRATER probe data, these parameters are recorded, namely CorrosionRate, Imbalance (pitting), and temperature. To change between the three graphs press "R" onthe keyboard to display rate, "I" to display imbalance, and "T" to display temperature. Only onegraph at a time may be zoomed in on the Y-axis. Zooming in on the X-axis is applied to allgraphs simultaneously.

Printing Corrosion Graphs

Hard copy printouts of CORRDATA Software graphs can be obtained from the MS DOSoperating system via the graphics command, which is loaded during the installation process.To print any screen use Shift + PrintScreen. DOS 3.3 did not provide graphics print


capability. DOS 4.01 added graphics printout for dot matrix printers. DOS 5.0 added laser jetand deskjet options. DOS 6.0 has the same capabilities as DOS 5.0. The printer selections aredetailed below:

NOTE: Depending on the PC and printer in use it may take tens ofseconds to print a full screen graphic display. DOS PrintScreen, howeveris one of the faster screen print utilities.

NOTE: For some portable PC's use of a second function key Fn isrequired for PrintScreen, such as the Compaq Contura. Consequently forShift + PrintScreen it is necessary to press Shift + Fn + PrintScreen.

deskjet: A Hewlett-Parkard DeskJet printer quietjet: A Hewlett-Packard QuietJet printer

graphics: An IBM Personal Graphics Printer, IBMProprinter, or IBM Quietwriter printer

quietjetplus: A Hewlett-Packard QuietJet Plusprinter

graphicswide: An IBM Personal Graphics Printer with an11-inch-wide carriage

ruggedwriter: A Hewlett-Packard RuggedWriterprinter

laserjet: A Hewlett-Packard LaserJet printer ruggedwriterwide: A Hewlett-Packard RuggedWriterwide printer

laserjetii: A Hewlett-Packard LaserJet Printer thermal: An IBM PC-convertible Thermal printer

paintjet: A Hewlett-Packard PaintJet printer thinkjet: A Hewlett-Packard ThinkJet printer

For other options or more detail see the MS-DOS Manual.

Test Graphical Displays

CORROSOMETER and CORRATER test graphs are included with software to show theappearance of several fixed corrosion rates. These graphs may be viewed and allow use of thecursors to measure the set corrosion rates.

These graphs may be retrieved from the CORRDATA sub-directory through the File andRetrieve sequence of the CORRDATA software. At the appearance of the pathname and filebox following the Retrieve sequence, change the pathname from *.DAT to *.SAV and pressEnter. This will display the two files CA_TEST.SAV and CO_TEST.SAV, in addition toany other files that may have been archived or saved to this directory. Press Tab to change tothe file box with a highlight bar. Use the 88 and 99 keys to select CO_TEST.SAV and pressEnter. To view the graph, press Display and View to show the following graph.


Figure 7.8 CORROSOMETER Test Graph

The slopes on this graph are 20 mpy, 10 mpy, 5 mpy, and 0 mpy respectively. Move thevertical cursor lines to select any constant slope portion of the graph. Press Enter to displaythe calculated corrosion rate between the cursors of the metal loss graph displayed.

Similarly the CORRATER test graph may alternatively be selected from the file retrieve box,to display the following graph with corrosion rates of 20 mpy, 10 mpy, 5 mpy, 2.5 mpy, and 0mpy respectively.

NOTE: With the CORRATER graph the average corrosion rate isdisplayed between the vertical lines, since the CORRATER directlymeasures corrosion rate compared to a CORROSOMETER whichmeasures metal loss, from which corrosion rate must be calculated.


Figure 7.9 CORRATER Test Graph

To exit either of these displays press Esc three times to return to the main program menu.

85

Chapter 8Maintenance

RDC Units

There is little requirement for maintenance on the RDC unit other than battery change-out andensuring that the probe connections remain clean.

Battery check and replacement is described in "RDC Battery Check and Replacement" inChapter 6. For guidance on the selection of probe reading intervals, see "Choosing ProbeReading Frequency" in Chapter 5.

The RDC unit also includes a small rechargeable battery for memory backup on one circuitboard, which is charged by the main battery. This rechargeable battery is set into operation atstart up of the RDC (see Figure 3.2). Its storage capacity with a dead main battery isapproximately three months.

WARNING! If the RDC is to be left inoperative for some timedisconnect the main battery and switch off the back up battery. Atstart up the back up battery MUST be switched on BEFORE themain battery.

CORRDATA Mate I or II

The only requirements for maintenance on these units are battery change-out, general care andcleanliness of the unit, and occasional inspection of the connectors for damage.

The Mate I or II operates with six AA battery cells. The use of alkaline batteries isrecommended which will give an average operating time of 40 hours when continuously usedwith RDC's only, or as few as 8 hours if used with probes only. ( Mate II only)

Low batteries are indicated by the screen cursor which changes from:

~ to LB

The Mate I & II have a small lithium battery back up on an internal circuit board with ananticipated life of 7 - 10 years. The unit must be returned to Rohrback Cosasco or itsauthorized representative for replacement of this battery.


PC CORRDATA Software

This requires no maintenance. If any problems occur contact the factory for assistance.

Software Revisions

The revision level of the PC software can be checked from the part number revision on thesystem diskettes.

The revision levels of the RDC unit and the Mate I or II may be checked with the Mate I or IIas follows:

Press the ON switch on the Mate I or II. Select Read (F1) from the start up screen to display:

What to Read?

PROBE MODE RDC EXIT

> > > >

F1 F2 F3 F4

Press the MODE (F2) to display:

SPECIAL TEST MODERun PMATE from PC

to update MATE.REV BAUD TEST EXIT

> > > >

F1 F2 F3 F4

Chapter 8 Maintenance 87

Press REV (F1) to display:

SOFTWARE REVISIONMATE = 7.4RDC = 6.8

EXIT

> > > >

F1 F2 F3 F4

If the Mate I or II is not connected to an RDC, the following screen will be displayed:

WARNING!No Response from RDC

Try again in 30 sec.EXIT

> > > >

F1 F2 F3 F4

Press EXIT (F4). This will display the revision of the Mate I or II without that of the RDC.

SOFTWARE REVISIONMATE = 7.4

RDC = 0. EXIT

> > > >

F1 F2 F3 F4

Switch OFF the Mate I or II when finished.

89

Chapter 9Troubleshooting

Troubleshooting any CORRDATA system problem will generally be done by treating the electronicsections as black boxes. By cross checking the basic components of the system i.e. batteries, probe,RDC, Mate I & II and PC it is possible to narrow down the problem unit. Any faulty electronic unitsmust be returned to the factory for repair.

RDC Unit Power Check

This unit, except for battery testing must be troubleshot with the Mate I or II. An RDC unitproblem will be suspected if only one RDC unit is malfunctioning.

1) Test RDC unit batteries with test switch adjacent to the battery connectorinside the RDC unit. Illumination of the red indicator shows a good battery.No illumination indicates a new battery is required.

2) A number of warning messages are displayed by the RDC unit which are selfexplanatory.

Checking Functional Operation of RDC with Mate

During initial configuration of the system, or at some later time if improper operation of theRDC or the probe is suspected, various operational tests can be made on the RDC with theMate I or II. TEST PROBES are supplied with every Mate I & II unit which can beconnected to the RDC's in place of the actual operating probe. These test probes provide apredetermined value which is read by the RDC and displayed on the Mate I or II.

To carry out the test, it is first necessary to suspend the normal data collection of the RDC.This is accomplished whenever the Mate I or II is connected to the RDC.


WARNING! Leaving the CORRDATA Mate connected to theRDC for periods greater than the normal reading interval willcause loss of data points.

Switch on the Mate I or II.



> > > >

F1 F2 F3 F4

Press SetUp (F4).



> > > >

F1 F2 F3 F4

Press RDC (F2).

Enter ID # > . . < 1-50

ENTER CLR BkSp EXIT

> > > >

F1 F2 F3 F4

Enter the ID number of the RDC unit or alternatively "0" if the RDC number is not known.Press ENTER (F1).

Chapter 9 Troubleshooting 91

RDC ConfigurationConnect Mate to RDC


> > > >

F1 F2 F3 F4

With the "Mate to RDC" cable attached to the Mate I or II, connect the Mate I or II cable tothe RDC and press TEST MODE (F3). Any problem of communication with the RDC willbe indicated by warning messages.


No Response from RDC RDC may be completing another Try again in 30 sec. operation. Retry in 30 secs. If display is the

same check batteries of RDC

RDC not configured Exit and configure RDC as described in theprevious section of the Chapter

RDC TEST MODESREADTEST READ READPROBE CONF TIME EXIT

> > > >

F1 F2 F3 F4

To read the test probe, press READ TEST PROBE (F1).

TEST PROBE MENU

START READ EXIT

> > > >

F1 F2 F3 F4


Disconnect the RDC cable from the corrosion probe and connect it to the test probe. Returnto the Mate I or II and press START (F1). This will cause the RDC to take a single probetest reading. The Mate I or II will indicate that a reading is being taken, as the followingscreen depicts.

RDC is now readingTEST PROBE. This will

take approx. 2 mins.EXIT

> > > >

F1 F2 F3 F4

Press EXIT (F4) to return to the previous screen. Allow at least 3 minutes for completionof the reading and press READ (F3).

If the RDC is a CORROSOMETER or CORROTEMP CORROSOMETER unit the displayshould display the divisions value and check value printed on the test probe.

TEST PROBE READINGS DIV: . . . CHK: . . .

EXIT

> > > >

F1 F2 F3 F4

For a CORRATER or CORROTEMP CORRATER RDC unit, the display will display a ratevalue and imbalance value corresponding to that printed on the test probe thus:

TEST PROBE READINGS Rate: . . . . MPY Imbal: . . . .

EXIT

> > > >

F1 F2 F3 F4

If the displayed values are beyond the limits shown on the test probe, the RDC unit may needrepair.


Press EXIT (F4) to return to the TEST PROBE MENU.

TEST PROBE MENU

START READ EXIT

> > > >

F1 F2 F3 F4

Remove the test probe and reconnect the cable to the working probe. Press EXIT (F4) toreturn to RDC Test Modes.

RDC TEST MODESREADTEST READ READPROBE CONF TIME EXIT

> > > >

F1 F2 F3 F4

Press READ CONF (F2) if you wish to verify the configuration information for the RDCunit. For an RDC CORROSOMETER the display will be as follows:

RDC . . CORROSOMETER Tag . . . . . . . . . . . . Type . . . . . Span . . . . Alloy . . . . . . . . MORE

> > > >

F1 F2 F3 F4

For an RDC CORRATER unit the display will be slightly different.


RDC . . CORRATER Tag . . . . . . . . . . . . Type . . . . . Alloy . . . . . . . . MORE

> > > >

F1 F2 F3 F4

In either case to read the rest of the configuration data press MORE (F4). The screen willdisplay the readings information. For readings set in hours the display will be:

Interval . . hours Num. Readings . . . . . Next. Reading . . . . .

EXIT

> > > >

F1 F2 F3 F4

Or for readings set in minutes the display will be:

Interval . . . minutes Num. Readings . . . . . Next Reading . . . . .

EXIT

> > > >

F1 F2 F3 F4

The Num. Readings shows how many readings have been collected (the maximum numberof readings for a CORROSOMETER RDC is 2048 readings for a CORRATER RDC orCORROTEMP CORROSOMETER RDC is 1024, and for a CORROTEMP CORRATERRDC is 512 readings).

If all information is correct press EXIT (F4).


Mate I or II

If the problems are common to all the RDC units, then the problem is probably with theMate I or II or the PC. It is possible to distinguish the difference between Mate I or II andPC problems, since RDC information can be displayed on the Mate I or II and at the PC.

To verify if the Mate I or II is operational, check the batteries and collect data from an RDCor probe which is known to be "good" (as much as this is possible) and use the displayroutine described in "Displaying Probe Data", in Chapter 6 of the manual. If the readingdisplayed is correct the Mate I or II is functioning and the problem may be with the PC orcommunication to the PC.

Checking Mate II Operation on Probes

The Mate I & II probe measurement circuitry may be tested by setting up an ID for eachprobe type to be tested which is outside the normal ID range in use: such as ID # 50 forCORROSOMETER probe and ID #49 for CORRATER probe. The probe may then be readlike a normal probe. Use of a separate probe ID will ensure that readings do not corrupt themain probe files.

Mate I & II Self Check System and Reprogramming Utility

If for any reason the Mate I or II software program has become corrupted, this will beindicated by the self check system that operates whenever the Mate is turned on. this systemindicates if any corruption of the software program has occurred.

To run this utility, plug the Mate I or II into the PC serial adapter cable. From theCORRDATA sub-directory type pmate and press Enter. The PC will display theinstructions of keys to press on the Mate I or II. This re-programs the Mate without losingany of the stored data.

NOTE: If the Mate I or II program has been severely corrupted, theabove utility will indicate that the utility pmatenew must be run. In thiscase, select the CORRDATA sub-directory, type pmatenew, andcarefully follow the on-screen instructions.

Whenever the Mate is switched on the self test occurs.

UNIT SELF TESTING

Please Wait!


Normally as the message clears the normal main menu screen will appear. However, if thefollowing screen appears the Mate should be reprogrammed.

Program ChKSum Error MUST REPROGRAM MATE ChKSum IS 29392

EXIT

> > > >

F1 F2 F3 F4

Pressing EXIT (F4) will clear the screen and allow operation of the unit. However, it isrecommended the Mate be reprogrammed as the effect of corrupted software may be difficultto predict.

PC

If the CORRDATA program does not start up on your computer, check to see if thespecification of your system meets the requirements listed in Chapter 2 of the manual.

If the program starts up but does not communicate with the Mate I or II, check the interfaceconnectors and ensure that the correct serial port is being used, and that the appropriateCOM1 or COM2 version of the software has been installed. If another device is using theselected serial port, either change the serial port being used by CORRDATA or use a switchbox.

Installing the alternate version of CORRDATA software for the other serial port is describedunder Installation in Chapter 3.

The CORRDATA program may be run under Windows 3.1 as a DOS application asdescribed in the Windows operating manual. Care must be taken with Windows set up,particularly with regard to other devices, such as a mouse, modem, or a network, that mayuse the same interrupt as the COM port used for communications with the Mate I or II. Ifdifficulties are experienced contact RCS for assistance.

If Problems Still Occur

If problems still occur following these basic "building block" tests, contact the factory forassistance.

97

Chapter 10ASCII Transfer Utility

When the CORRDATA Software is installed to the hard disk of the PC, a spreadsheet utility fileMAKE_ASC.EXE is also included. This utility may be used to convert the CORRDATA datafiles (with extension.DAT) to ASCII files which may be imported directly to spreadsheets suchas Lotus 1-2-3. The file names are automatically created by the utility with the general formID_X.PRN, where X is the probe ID number, and saved in the CORRDATA directory.

To operate this utility, change to the CORRDATA directory and type MAKE_ASC.EXE. Ifrunning under Windows, double click on the MAKE_ASC.EXE file in the CORRDATA directoryin File Manager. This will immediately generate converted .PRN files for each .DAT file.

To import the file into Lotus 1-2-3, start the Lotus 1-2-3 program. Select the menu, and enterFile; Import; Numbers. Modify the directory to the location of the saved .PRN files and pressEnter. In Lotus version 4 or 5 for Windows, select File; Open; select the File Type to text (txt,prn); change the Directory to CORRDATA; click on the required file ONCE; select theCOMBINE button and select formatted and OK. For Excel or other spreadsheets make sure thatthe field delimiter is set to comma. Select the file or files as required. The ASCII format for aCORROTEMP probe, for example, is as follows:

"Rohrback Cosasco Systems, Inc."CORRDATA ASCII TRANSFER UTILITY"(C)Copyright 1992""","CORROTEMP PROBE"""TAG","","AE 0023""ID","","23""TYPE","","D""SPAN","","10.00""INTERVAL",""," - ""INSTALLED","","30 Sep 92""LAST READ","","15:34 30 Sep 92"""" TIME ","TEMP","METAL LOSS ""(DAYS)","(DEG C)","(MILS) " 0.649,28.000000,0.980000


The three columns of data depend on the probe type as follows:

Column 1 Column 2 Column 3 Column 4

CORROSOMETER Time - Metal Loss

CORROTEMP CORROSOMETER Time Temperature Metal Loss

CORRATER Time Imbalance Corrosion Rate

CORROTEMP CORRATER Time Imbalance Corrosion Rate Temp

When imported into Lotus 1-2-3, the appearance is as follows:

A B C D1 Rohrback Cosasco Systems, Inc.2 CORRDATA ASCII TRANSFER UTILITY3 (C)Copyright 199245 CORROTEMP PROBE67 TAG 00238 ID 239 TYPE D10 SPAN 10.0011 INTERVAL - 12 INSTALLED 30 Sep 9213 LAST READ 15:34 30 Sep 921415 TIME TEMP METAL LOSS 16 (DAYS) (DEG C) (MILS) 17 0.649 28 .98

The first column is the time base in days from midnight at the start of installation. The decimalportion indicates the time of day, i.e. 0.25 is 6:00 a.m., 0.5 is mid-day, 0.75 is 6:00 p.m., etc.This time is computed for every probe reading independent of whether an RDC is used or not. Ifthe readings are from probes with RDC's, the INTERVAL above will indicate the reading intervalin addition to the actual times computed for column 1.

For graphical displays, set graph type to XY, and select the data range to be displayed as required.

99

Chapter 11Mate Operation with Downhole Corrosion Monitor System (DCMS)

The operating of the CORRDATA System with the downhole corrosion monitor is almost identicalto that with an RDC. The main difference is that communication with the downhole tool is carriedout at a data transfer rate of 300 Baud instead of 9600 Baud used between the Mate and RDC, andthe Mate and PC.

This requires that the baud rate is set to 300 to communicate with the downhole corrosion monitorand then reset to 9600 baud to communicate with its PC.

NOTE: A special interface unit supplied with the downhole tool isrequired to connect to the downhole corrosion monitor.

To change the baud rate, switch ON the Mate. After the self test screen clears and the main menuappears.



> > > >

F1 F2 F3 F4

Press Read (F1); MODE (F2) to display the screen.


Special Testing CodeRun PMATE from PC

to update MATE

REV BAUD TEST EXIT

> > > >

F1 F2 F3 F4

Press Baud (F2) to display.

Baud Rate is 9600Select 300 for DMT9600 for RDC or PC

300 9600 EXIT

> > > >

F1 F2 F3 F4

Press 300 (F1) for downhole corrosion monitor tool. This Mate will automatically shut off andrestart with the Baud Rate Changed.

WARNING! Remember to repeat the procedure and set the Baudrate to 9600 to communicate with the PC.

Appendix A 101

Appendix A

Theory of Operation of CORROSOMETER Systems

CORROSOMETER Systems are based on the electrical resistance method of corrosion monitoringpioneered by Rohrback in the 1950's and 1960's. CORROSOMETER probes are basically"electrical coupons." They determine the loss of metal from the probe by measuring the changein its resistance. Because of the very low resistances involved, very sensitive monitoring circuitsare used in CORROSOMETER instruments to measure the change in probe resistance comparedto a protected reference element resistance series-connected to the corroding measurement element.A "check" element is also included and is protected from the process along with the referenceelement. The ratio of check to reference resistance should remain constant. If it doesn't, thisindicates that degradation of the reference element may be occurring and that metal loss readingsobtained from the probe are questionable. A simplified diagram of a typical electrical resistancemonitoring circuit is shown in Figure 1.

FIGURE 1


As with coupons, CORROSOMETER probes must be allowed to corrode for a period of timebefore accurate corrosion rate measurements can be made. The actual length of time requireddepends upon the corrosion rate--the higher the rate, the shorter the time required, and vice-versa.CORROSOMETER probes are available in a variety of styles and with useful probe life ("span")ranging from 2-25 mils, in styles commonly used in process piping systems. Instrumentation tomeasure electrical resistance probes divides the probe span into l000 "divisions." A probe witha 2 mil span is therefore theoretically capable of measuring thickness changes of 0.002 mils. Inpractice, however, we recommend that a change in indicated metal loss of l0 divisions be requiredbefore the data is used to calculate corrosion rate. Indications of an upward or downward trendcan be obtained with as little as a 4-division change, but care must be exercised in interpretingsuch small changes because other factors (e.g. temperature changes) can also be responsible. Theactual time required to produce meaningful corrosion rate information with common probe spansat different corrosion rates is shown in Figure 2 and summarized in Table 1.

FIGURE 2

Appendix A 103

CorrosionRate(mpy)

Probe Span (mils)

2 4 5 10 20 25

0.1 73 days 5 months 6 months 12 months 24 months 30 months

0.5 15 days 29 days 37 days 73 days 5 months 6 months

1.0 7 days 15 days 18 days 36 days 73 days 3 months

5.0 35 hours 3 days 4 days 7 days 15 days 18 days

10 18 hours 35 hours 2 days 4 days 7 days 9 days

25 7 hours 14 hours 18 hours 35 hours 3 days 4 days

50 4 hours 7 hours 9 hours 18 hours 35 hours 2 days

75 140 mins 5 hours 6 hours 12 hours 23 hours 29 hours

100 105 mins 4 hours 5 hours 9 hours 18 hours 22 hours

TABLE 1

Elapsed Time* To: CorrosionRate*

with 10 milSpan Probe

Early TrendIndication(4 Div.)

MeaningfulRate Data(10 Div.)

End of UsefulProbe Life(1000 Div.)

1.6 hours 4.0 hours 17 days 220 mpy(5.6 mm/y)

4.0 hours 10.0 hours 1.4 months 88 mpy(2.2 mm/y)

9.6 hours 1 day 3.3 months 37 mpy(0.94 mm/y)

18.0 hours 1.8 days 6.0 months 20 mpy(0.51 mm/y)

1.1 days 2.7 days 9.0 months 13 mpy(0.33 mm/y)



2.2 days 5.5 days 18.0 months 6.7 mpy(0.17 mm/y)


* All data shown to two significant digits only.

TABLE 2

From Table 1, it would appear desirable to always choose probes with the lowest span availablein order to get the greatest sensitivity. However, the more sensitive the probe, the faster the entireprobe span will corrode away and require a new probe to be installed.


Table 2 illustrates this relationship.

It is our experience that the objectives of most monitoring programs can be achieved cost-efficiently by selecting CORROSOMETER probes which will reach the end of their useful life in6 - 9 months at the expected corrosion rate. Unlike a monthly coupon replacement program, thiselectrical resistance probe will continuously produce data that verifies that the average corrosionrate over the previous 2-3 days is still at the originally-expected (design) rate. If the corrosion rateincreases to twice the design rate, meaningful data to permit the new rate to be calculated will beavailable in a day and a half. Conversely, if the actual corrosion rate is below design, a longerperiod is required before meaningful data are available to calculate the new rate.

CORROSOMETER probe elements are available in a variety of styles. A selection of theavailable styles is shown in Figure 3. Wire, tube, and strip-loop styles all have a loop of metalexposed to the process. The loop protrudes from the end of the probe body through either ahermetic glass seal or a Teflon/ceramic, Teflon/epoxy or epoxy seal/packing system. Choice ofmaterials is dependent upon stream composition, process conditions and performancerequirements. Cylindrical elements utilize specially-made, thin-wall tubing as the measurementelement. Cylindrical probes are generally "all-metal;" i.e., there is no other material exposed tothe process. There are, however, also some cylindrical probes available which join the probe bodyat a hermetic glass seal. A variety of flush-mounted probes are also available; so-called becausethe measuring element is mounted parallel to the flow stream, flush with the inside pipe wall.

FIGURE 3

CORROSOMETER monitoring systems can be applied to all processes. However, some typesof CORROSOMETER probes are better suited to the requirements of particular applications thanothers.

Different styles of CORROSOMETER probes are affected to different degrees by pitting attack.Figure 4 shows the results of pitting attack on a wire loop probe. Although the remaining wirethickness shows that only 30% or so of the probe span has been consumed, the probe is obviouslyout of service. Cylindrical elements on the other hand, are affected to a much lesser degree bypitting because of the much larger circumference of the measuring element. Wire loop and tube

Appendix A 105

loop elements also have a tendency to be electrically shorted by a bridge of iron sulfide corrosionproduct. This is especially prevalent in low-velocity streams over an extended period. The effectof such bridging is to reduce the measured metal loss of the probe, creating a misleadingly lowcorrosion rate. Cylindrical probes demonstrate more resistance to iron-sulfide bridging due to theirconstruction and lower inherent resistance per unit length, thus minimizing the effect of the shuntresistance. Where pitting or substantial FexSy deposition are expected to be problems, cylindricalprobes should be chosen wherever possible over loop-style probes.

FIGURE 4

Most cylindrical probes are of all-welded construction in order to eliminate the need for sealingmetal elements to non-metallic glass, epoxy or ceramic. This all-welded construction gives theprobe superior resistance to leaking. Probes with higher temperature ratings can also beconstructed in the all-welded style. A drawback to the all-welded style is that the element iselectrically connected to the pipe wall which can, in certain conditions, interfere with the corrosionreaction on the probe. Also, because cylindrical probes are welded, in some conditions preferentialcorrosion can occur in the heat-affected zones near the weld.

Flush probe elements are thin, flat metal sections embedded in epoxy or a hermetic glass sealinside a metal probe body. Flush probes also experience certain characteristic problems, mostnotably: lack of adhesion of the metal element to the epoxy, cracking of glass seals due todifferential expansion and erosion of the epoxy or glass due to high velocities, abrasive materialsin the flowstream or both. Flush CORROSOMETER probes mounted on the bottom of the linehave been shown to provide good results in a sour gas gathering system.

Because the measurement element is part of the primary pressure seal, and because it's designedto corrode, CORROSOMETER probes have a reduced resistance to leaking after prolongedexposure. Once the measurement element has corroded through, the internals of the probe bodyare exposed to the process fluid. Although materials are chosen in part for their strength and lackof permeability, it is our experience that process fluids will permeate throughout the probe packingmaterial. For this reason, quality probes are constructed of corrosion-resistant body materials andinclude a secondary pressure seal, often consisting of a hermetic glass-sealed connector. Otherback-up seals are utilized in special cases, especially where process fluids will attack glass (e.g.


hydrofluoric acid service). Please contact the factory if you have any questions about thecompatibility of probe materials with your application.

The reference and check elements are protected from the process to which the measurementelement is directly exposed. Temperature changes in the process will, therefore, affect the measureelement before the reference and check elements. Because of the very low resistances involved,these changes can significantly affect the metal loss readings. CORROSOMETER probesincorporate special design features to minimize the thermal resistance of the materials insulatingthe reference and check elements from the process. It should also be noted that cylindrical probesare inherently better able to react to temperature changes due to location of the reference and checkelements concentrically inside the measure element.

107

Appendix B

Theory of Operation of CORRATER Systems

CORRATER systems measure the instantaneous corrosion rate of a metal in a conductive fluidusing the linear polarization resistance ("LPR") measurement technique. Corrosion is anelectrochemical process in which electrons are transferred between anodic and cathodic areas onthe corroding metal resulting in oxidation (corrosion) of the metal at the anode and reduction ofcations in the fluid at the cathode.

Sterns and Geary originally demonstrated that the application of a small polarizing potentialdifference ()E) from the corrosion potential (Ecorr) of a corroding electrode resulted in a measuredcurrent density (imeas) which is related to the corrosion current density (icorr) by equation (1):

)E = ba bc (1)imeas (2.303 icorr) (ba + bc)

where: ba = Anodic Tafel Slopebc = Cathodic Tafel Slope

Since the Tafel coefficients are more or less constant for a given metal/fluid combination, imeas isproportional to icorr which is proportional to the corrosion rate. Equation (1) and the entire LPRtechnique are only valid when the polarizing potential difference is very low (typically up to 20mV). In this region the curves are linear, hence the term LPR.

Inspection of Equation (1) shows that the result is a resistance, the Polarization Resistance, Rp.While strictly speaking, there are both anodic and cathodic Rp values, which can differ, they areusually assumed to be equal. The resistance to current flow between anode and cathode on theLPR probe is the sum of both polarization resistance values and the resistance of the solutionbetween the electrodes (RS) as shown in Equation (2):

E = imeas (2Rp + RS) (2)

From Equations (1) and (2), obtaining results from the LPR technique would seem to require onlyinstantaneous readings of resistance. In practice, however, the determination of polarization


resistance is complicated by a capacitance effect at the metal-fluid interface (double-layercapacitance). Figure B-1 is an equivalent electrical circuit of the corrosion cell formed by themeasuring electrodes and the fluid, showing the importance of RS and double-layer capacitanceeffects.

FIGURE B-1: Equivalent Circuit of LPR Probe

The effect of the double-layer capacitance is to require the direct current flow to initially charge-upthe capacitors, resulting in a decaying exponential current flow curve vs. time after application ofthe polarizing potential difference. A typical LPR current vs. time curve is shown in Figure B-2.

Each metal/fluid interface has its own characteristic capacitance which in turn determines theamount of time required to obtain valid measurements of icorr and corrosion rate. The actual timerequired can vary from a few seconds up to 20 minutes, depending upon the metal/processcombination being measured. Choosing too short a polarization time can result in current readingsmuch higher than the true icorr thus causing measured corrosion rate to be lower than actual,sometimes by a significant amount.

Appendix B 109

FIGURE B-2: Typical LPR Current vs. Time Decay Curve

Solution resistance can also have a significant effect on accuracy if it is relatively high comparedto the polarization resistance. In most industrial water applications, conductivity of the solutionis high and solution resistance is low compared to the polarization resistance, so imeas is an accuratemeasure of polarization resistance, and therefore, corrosion rate.

A serious problem develops, however, when the solution resistance increases or the polarizationresistance decreases enough to make the solution resistance a significant portion of the totalresistance to current flow between the electrodes. In these cases, the accuracy of the LPRmeasurement is affected. This situation tends to occur at high corrosion rates (low polarizationresistance) and in solutions with low conductivity (high solution resistance) and is manifested bythe indicated (measured) corrosion rate being lower than the actual corrosion rate. The graph inFigure B-3 shows the effect of this limitation on the recommended operating range of LPRinstruments.


FIGURE B-3 Operating Range of LPR InstrumentsCorrosion Rate vs. Solution Conductivity

Appendix B 111

Several techniques have been used over the years to minimize the impact of solution resistance onLPR measurements. The most common techniques involved the use of a three electrode probe.The effectiveness of the reference electrode in reducing the effect of solution resistance has beenshown to be dependent upon the proximity of the reference electrode to the measurement electrode.Rohrback Cosasco three-electrode probes (see Figure B-4) are unique compared to other majorLPR probes because they utilize a closely-spaced electrode.

FIGURE B-4: Rohrback Cosasco 3-Electrode Probe Configuration

A better way to deal with this problem, however, is to directly measure and compensate for thesolution resistance. Rohrback Cosasco has exclusive patent rights to the Solution ResistanceCompensation (SRC) technique incorporated in top-of-the-line RCS-8, RDC CORRATER, 9030and 9134 instruments. In this method, a high-frequency a.c. voltage signal is applied between theelectrodes short-circuiting Rp through the double-layer capacitance, thereby directly measuring thesolution resistance. The state-of-the-art, patented SRC technology also eliminates the need for athird electrode, even in low conductivity solutions. Consequently, Rohrback Cosasco's two-electrode probes have become the standard RCS offering, with the three-electrode probe availableon special order only.

The above points are clearly indicated in ASTM Standard Guide G96 which quotes:

"3.2.8 Two-electrode probes and three-electrode probes with the reference electrode equidistant from the test andauxiliary electrode do not correct for effects of solution resistance without special electronic solution resistancecompensation. With high to moderate conductivity environments, this effect of solution resistance is notnormally significant.

3.2.9 Three-electrode probes compensate for the solution resistance RS by varying degrees depending on the positionand proximity of the reference electrode to the test electrode. With a close-spaced reference electrode, the effects


of RS can be reduced up to approximately ten fold. This extends the operating range over which adequatedetermination of the polarization resistance can be made.

3.2.10 A two-electrode probe with electrochemical impedance measurement technique at high frequency short circuitsthe double-layer capacitance, Cdl, so that a measurement of solution resistance RS can be made for applicationas a correction. This also extends the operating range over which adequate determination of polarizationresistance can be made."

CORRATER Instruments

Rohrback Cosasco's current CORRATER product line includes the Model 9000 portableCORRATER instrument which has a fixed time cycle and does not include the SRC feature; theModel 9030 single-channel instrument with user-selectable cycle time which pioneered the use ofSRC in CORRATER instruments; and three instruments - the Model RDC - CORRATER, theModel RCS-8 and the Model 9134 CORRATER Probe Interface Module, which incorporateproprietary, fully-automatic cycle time selection and advanced SRC features.

Imbalance (or Pitting/Index)

In addition to general or uniform corrosion, localized corrosion (pitting) may occur in a system.This can result in much more rapid failure of a structure than a simple measure of corrosion ratewould indicate. A pit on the metal surface is the result of a localized, high anodic current density.Positive ions flow away from the pit into the solution and electrons flow away from the pit intothe surrounding metal.

If it were possible to place a zero-impedance ammeter between the pit and the nearby metalsurface, the current in the anode-cathode system of the pit could be measured. Individualmeasurements are not practical because the areas are small. Instead, current flow between the twometallurgically identical electrodes of a CORRATER probe under short-circuit conditions can beused to indicate pitting tendency. All Rohrback Cosasco CORRATER instruments include aimbalance/pitting reading. The user should note that this is a qualitative measurement (or index)and utilize it accordingly. It has proven very useful in many applications (e.g. cooling watertreatment) and offers information not generally available about a system except by coupons whichlag behind actual events and offer no way of detecting upsets.

If the pitting reading is low compared to the corrosion reading, the pitting problem will probablybe minimal. On the other hand, a pitting reading which is high compared to the corrosion readingcan indicate that pitting or crevice corrosion will be the main form of corrosive attack. When thereadings are about equal, some pitting is indicated, but the pits will probably be broad and shallow.

723002 manual rev g

Documents

rdc mate

rdccorrotemp corrosometer

rdccorrotemp corrater

rdc units85corrdata

pc corrdata software

corrotemp corrosometerprobe

corrosometer probe graphs

corrdata basic pc software