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LOGIX

OPERATION AND MAINTENANCE MANUAL

FOR THE TRACERCO PROFILERTM

Pavilion 11 Coxwold Way Belasis Hall Technology Park Billingham Cleveland TS23 4EA U.K. Tel. +44 (0) 1642 375500 Fax +44 (0) 1642 370704

Document Number : MI0025

Revision : F

Issue : 0

Date : 22/06/2007

SIGNED / DATED

0

F DCE Reference removed I.Mc 22/06/07

G Barker 22/06/07

G Barker 22/06/07

0

E General update I.Mc 01/03/07

G Barker 01/03/07

C Hart 01/03/07

0 D Document main title corrected I.Mc 25/04/06

C Hart 25/04/06

C Hart 25/04/06

0 C Contact Information Added T Cushley 20/02/06

C Hart 20/02/06

C Hart 20/02/06

0 B Labview SCADA package added

G. Barker 23/02/05

C. Hart 10/03/05

C. Hart 10/03/05

0 A Original issue

I.Mc 08/09/04

P.Keay 09/09/04

G. Barker 09/09/04

ISSUE REV REVISION DESCRIPTION AUTHOR CHECKED APPROVED

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Title: Tracerco ProfilerTM Operations Maintenance Manual

General information The manufacturer accepts no liability for any consequences resulting from inappropriate, negligent or incorrect usage. The contents of this manual are believed to be correct at the time of printing. All rights reserved.

Contact Information

In the event of any safety, Tracerco Profiler operation queries please contact TRACERCO for information. TRACERCO Pavilion 11 Coxwold Way Belasis Hall Technology Park Billingham Cleveland, UK TS23 4EA

Tel: +44 (0) 1642 375500 Fax: + 44 (0) 1642 370704 Email: [email protected] URL: www.tracerco.com

24 Hours Emergency call out Numbers Instrument related problem: +44 (0) 7885 667494 Radiological Protection Advisor: +44 (0) 7889 828968 This document is a private and confidential communication and the property of Johnson Matthey PLC, it must not be loaned or copied without the prior consent of Johnson Matthey PLC and must be returned.

http://www.synetix-services.com/

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TABLE OF CONTENTS

CONTACT INFORMATION ......................................................................................................................................... 2 24 HOURS EMERGENCY CALL OUT NUMBERS ................................................................................................................. 2

1 INTRODUCTION ................................................................................................................................................... 5

2. RADIOLOGICAL SAFETY .................................................................................................................................. 9

3. NORMAL OPERATION......................................................................................................................................... 10 3.1 START-UP .............................................................................................................................................................. 10 3.2 NORMAL OPERATING MODES .......................................................................................................................... 11

Interface Mode......................................................................................................................................................... 11 Density Mode ........................................................................................................................................................... 11

3.3 SHUTDOWN...................................................................................................................................................... 11 4. PLC SOFTWARE FUNCTIONALITY............................................................................................................... 12

4.1 MODBUS COMMUNICATION PARAMETERS....................................................................................................... 12 4.2 OPERATIONAL PARAMETERS............................................................................................................................ 13

Configuring the Dead Time ..................................................................................................................................... 13 Configuring the Filter Factor .................................................................................................................................. 13 Configuring the Isotope Half Life ............................................................................................................................ 13

4.3 RAW DATA AND WEIGHTING FACTOR MAPPING.............................................................................................. 14 Unmapped Raw Count Data Locations ................................................................................................................... 14 Weighting Factor Data Locations ........................................................................................................................... 14

4.4 DENSITY DEFINITION SET POINTS.................................................................................................................... 14 Maximum Upper Limit (Set Point)........................................................................................................................... 15 Minimum Lower Limit Test...................................................................................................................................... 15 Set Point Concurrency ............................................................................................................................................. 15

4.5 ACCUMULATING RAW COUNTS........................................................................................................................ 16 Configuring the Extended Counting Period ............................................................................................................ 16 Starting the Sequence .............................................................................................................................................. 16

4.6 CALIBRATION PROCEDURES............................................................................................................................. 17 Calibration Status Registers .................................................................................................................................... 17 Initiating the Calibration Sequence......................................................................................................................... 18 Performing a Background Calibration.................................................................................................................... 18 Performing a Reference (Empty) Calibration.......................................................................................................... 19 Recalculation of Calibration Data .......................................................................................................................... 20 Manual Adjustment of K Factors............................................................................................................................. 20 Configuring the Density Value ................................................................................................................................ 21

4.7 ALARM CONFIGURATION ................................................................................................................................. 21 Detector Tube Alarms.............................................................................................................................................. 21 Detector Tube Alarm Counter ................................................................................................................................. 22 Alarm Compensation ............................................................................................................................................... 22 ModBus Communication Port Failure Alarms ........................................................................................................ 22 Interface Alarms ...................................................................................................................................................... 23 General Alarm ......................................................................................................................................................... 23 Global Alarm Reset.................................................................................................................................................. 24

4.8 ANALOGUE OUTPUT ........................................................................................................................................ 25 Interface Level Display Registers ............................................................................................................................ 25

4.9 DIGITAL OUTPUT (IF FITTED) ........................................................................................................................... 26

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5. MAINTENANCE ..................................................................................................................................................... 27 5.1 WIRING AND HOOK-UP DESCRIPTION – THE POWER SUPPLY TO THE PROFILER...................................................... 27

Connection in the safe area ..................................................................................................................................... 27 Connection at the vessel .......................................................................................................................................... 27

5.2 WIRING AND HOOK-UP DESCRIPTION – THE OPTICAL CABLE CONNECTION............................................................ 28 5.3 INTRINSIC SAFETY CONSIDERATIONS .................................................................................................................... 28 5.5 FAULT LOCATION ................................................................................................................................................. 29

PLC orTracerco ProfilerTM Error.......................................................................................................................... 29 5.6 ROUTINE MAINTENANCE/INSPECTION.................................................................................................................... 30

6 SCADA SYSTEM .................................................................................................................................................. 31 6.1 INSTALLING NEW APPLICATION............................................................................................................................. 31 6.2 OVERVIEW ....................................................................................................................................................... 32 6.3 VESSEL OVERVIEW........................................................................................................................................ 33 6.4 DIAGNOSTICS SCREEN ..................................................................................................................................... 34 6.5 TRENDING DISPLAY ......................................................................................................................................... 35 6.7 SETPOINTS....................................................................................................................................................... 37 6.8 PLC STATUS SCREEN ...................................................................................................................................... 38 6.9 CALIBRATION STATUS ..................................................................................................................................... 39 6.10 VALUE TABLES ................................................................................................................................................ 40

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1 Introduction

Separation vessels contain materials such as gas, oil, water and sand in different phases as shown in figure 1. Each phase has a different density. The Tracerco ProfilerTM- measures the density (real or apparent) and the extent of these phases within the vessel. The interface of the various phases can then be calculated with respect to the vessel height. The information provided can then be used to control on the interface levels.

Figure 1 – Typical Separation Vessel

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The Tracerco ProfilerTM incorporates a neck, which is used to connect to a flange on the vessel. Three titanium dip-pipes project into the vessel from the neck, one collimator and two probe tubes. Each probe tube contains an array of radiation detectors in the form of Geiger Muller Tubes. Titanium dip-pipes allows the use of low energy Americium241 sources enabling small changes in product density to be detected, thus providing more information with regard to phase dispersion than a standard instrument. The dip pipes are designed in accordance with pressure vessel design code to suit the vessel design conditions.

Figure 2 – Probe Collimator and Detector Arrangement The narrower of these tubes holds a source-arming rod that contains a series of sources along its length. The rod is surrounded by a tube called a collimator which has small holes drilled in it at each source level as shown in figure 2.. These holes direct a narrow beam of radiation towards a selected Geiger Muller tube in the probes, which are mounted in separate dip pipes. The rod is attached to the arming mechanism on the top of the gauge. When the arming mechanism is locked in the shut position the alignment of the sources and the collimator is such that the sources are isolated and the radiation from the gauge is at a safe level. Material between the two dip pipes will attenuate the radiation and so the intensity of radiation seen by a GM tube is related to the density of the intervening material.

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Geiger Muller Tubes are mounted within the dip pipe arrangement, 3 High Voltage generator units mounted on the signal processor board power maximum of 25 Geiger Muller tubes each. Each Geiger Muller Tube output is processed by a pulse shaping amplifier mounted on the dip pipe PCB, this produces a useable signal. The output of these amplifiers is connected to the signal processing board via a multi-way cable. Pulses from the GM tubes are counted in the Signal Processor unit using counters. Values in these counters are made available for analysis via a micro-controller and an optical transceiver. These units are within the neck and dome of the gauge, which is rated to IP66.

Figure 3 – Electrical System Diagram Figure 3 shows the Electrical System Diagram. A Galvanic Isolator, normally fitted in the main panel, powers each probe with 10V DC produced. Communication between the probe and the PLC is achieved using Modbus protocol. For safety, communications in the field is over a fibre optic cable. The Fibre optic signal is converted to an electrical signal in the main panel using a Fibre optic modem.

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A PLC collects the information and calculates the density (real or apparent) of the material for each individual GM tube. Thus a density or interface profile of the vessel can be achieved. Density bands are allocated for each of the six phases, the top level of these phases can then be calculated with respect to vessel or instrument height. Pre-set low and high-level alarms for each interface level are incorporated into the PLC software. The levels of which can be adjusted on installation to suit the plant requirements. These levels can be read for control purposes via the hardwired analogue & digital outputs or digital communications via PLC. The MMI system can then display the vessel profile or position of the various phases in the vessel. Figure 4 shows a typical screen shot of an MMI screen with gas, foam, oil, emulsion, water and sand phases. Failure of signal processor boards, communications or GM tubes generates an alarm for indication on the MMI. Electrical Equipment Certification Service (EECS) has certified the design and production of the gauge to meet the European requirements for use in potentially explosive atmospheres. The system complies with European Electro-Magnetic Compatibility regulations and has been independently tested.

Figure 4 – Typical Screen Shot

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2. Radiological Safety

It is our normal practice to supply all equipment as specified except the radioactive sources. These will normally be shipped to site prior to commissioning by Tracerco Services engineers. The sources will be shipped in a suitable type “A” container. This ensures that the sources are safely packed and shielded for transport. When shipped to site, the sources should be kept in a safe area (e.g. Radiographer’s store) until the arrival of Tracerco Services commissioning engineers, who will install the source array into its dip-pipe. Prior to arrival of the sources, the site registration should be amended to include the additional sources. Tracerco Services Radiation Protection Advisor (RPA) may be contacted for advice with regard to licenses, registration, etc. The system specified is designed to fulfil the requirements of the UK Ionising Radiation’s Regulations 1999, reducing the emission of radiation from the source array to a safe level. The profiler contains Americium-241 sources. The sources emit a low energy (60keV) gamma ray that is easily shielded. When the profiler is operational there will be no measurable dose rate outside of the vessel from the sources even when the vessel is empty. The sources are all contained within a single arming rod, which is locked into place and must not be removed by unauthorised persons. The arming rod can be locked shut with the sources in place, for removal by an authorised person. For vessel entry during shutdown the arming rod can be locked shut. This is achieved by pushing down on the lever at the neck of the profiler and inserting a padlock into the hole provided. This action withdraws the sources behind a shield and reduces the dose rate to less than 7.5 micro-seiverts/hr at 10cm. Because it is not possible to receive an effective body dose > 7.5 micro-seiverts/hr, then a controlled area is not required. The lever should not be locked in the open position but may be wired or pinned to prevent accidental operation. For vessel entry the array of sources can be isolated.

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3. Normal Operation

The PLC program will prevent normal operation until the gauge has been installed and commissioned. The following procedures are intended to be followed by production operators during start-up and shutdown of the gauge.

3.1 Start-Up Prior to start-up check that the plant control system is not using the gauge for control and the profile gauge system is switched off. Move the arming rod as shown in figure 5 to the open position and switch the system on. Allow 30 seconds for the PLC system to boot up and stabilise. Check that the indications coming back from the system are representative of the vessel conditions. If the vessel is shown as full of sand then the arming rod is not aligned, re-check that the arming rod is in the fully open position. When the system has stabilised and is representative of the vessel conditions, switch the plant control system over to gauge control.

Figure 5 - Diagram showing gauge dome and arming rod

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3.2 Normal Operating Modes There are two modes operation. When operating in the Interface Mode the gauge calculates position of each interface, it does not calculate the actual density value. The density mode calculates a density value for each detector. Interface Mode In this mode no recalculation of density values is performed. The Tracerco ProfilerTM instrument determines the interface of the different phases from the water and air calibrations performed. This mode produces a PHASE profile from the different absorption coefficient effect of the various materials in the vessel. The other materials in the vessel i.e. Oil have different absorption coefficients than Water. This is critical as the density information is obtained from the materials radiation absorption characteristics. Using this method the density readings of the oil in the vessel may not be the same as the sample taken from the vessel, and then measured by other means. However this is often desirable as it means that two materials with similar densities (Oil at 0.95g/ml and Water at 1g/ml), will produce a bigger density reading difference. The difference in density readings will be greater, therefore the interface will be more visible and easier to control. Density Mode

In this mode a recalculation is performed on the density values produced. Since it is not normally possible to fill the vessel with oil this method effectively performs a re-calibration of the oil and emulsion values. To produce specific density values for each point two constants must be entered in order to run the re-calculation procedure.

Known density of the Oil (Poil) In the vessel Known density of the water in the vessel

3.3 Shutdown Prior to shutdown ensure that the gauge is not being used for plant control. Switch the system off. Move the arming rod on the head of the gauge from the open position to the shut position as shown in figure 5, if necessary the arming rod can be padlocked shut.

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4. PLC Software Functionality

The information contained within this section details the procedure required to control the functionality of the High Resolution Tracerco Profiler TM Software. This includes the ability to optimise the software in relation to the hardware configuration, and provide the ability to control the calibration process.

4.1 ModBus Communication Parameters An individual ModBus address is required for each of the High Resolution Tracerco ProfilerTM Detector Nodes. The addresses defined within the software must be identical to the address configuration of the Signal Processor Unit. Changing the addresses within the PLC software is a simple case of modifying 2 internal data registers, one for Detector ‘A’ and the other for Detector ‘B’. Configuration of the ModBus address of Detector ‘A’ is achieved by manually entering a value between the limits of 5 and 247 into data register [SP_WORD[3]], using the RSLogix Programming Software. The Default Address of Detector A is 5. Configuration of the ModBus address of Detector ‘B’ is achieved by manually entering a value between the limits of 5 and 247 into data register [SP_WORD[4]], using the RSLogix Programming Software. The Default Address of Detector B is 10. The Update Interval register is common to both Detectors ‘A’ and ‘B’. The value entered determines how often the Detectors update, or refresh, the Raw Count data.

Configuration of the Update Interval is achieved by manually entering a value between the limits of .50 and 15.00 (seconds) into data register [SP_REAL[0]], using the RSLogix Programming Software or Diagnostics SCADA/MMI graphic. Note: If the Update Interval is set to a low value of say, 0.50 seconds, the PLC processor will be working extremely hard in order to cope with the demand on the communications network; for this reason it is important that the Update Interval is set at an optimum value in line with the process conditions, and not necessarily to give the fastest possible update.

The Update Interval is also used in the calculation of the ModBus fault time. Please be aware that adjustment of the Update Interval will directly effect the time delay before ModBus communication port fault alarms are enabled.

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4.2 Operational Parameters Normal Operation will only be activated when all three Calibration Status Registers have a status of 3 to indicate that all calibration data has been calculated and is valid.

In Normal Operation, raw data will be gathered from the two Detector heads. This data is then used to calculate the current density of materials stored within the storage Vessel using several mathematical routines.

Normal Operation is fully automatic, with no manual intervention required, unless certain working parameters or set points require adjustment.

Configuring the Dead Time The recovery time for a Geiger Muller tube after it has detected a radioactive particle is known as Dead Time. The calculation below is used to determine the corrected counts (nc) from the observed counts (no) and the dead time (τ).

nc = _1___ 1 - no τ

Configuration of the Dead Time is achieved by manually entering a value between the limits of 50 and 150 (microseconds) into data register [SP_REAL[10]], using the RSLogix Programming Software. The Default Value for Dead Time is 90, this value should not be changed unless a Tracerco engineer is consulted.

Configuring the Filter Factor The Filter Factor is used during the smoothing process in order to filter out irregular Raw Counts. Configuration of the Filter Factor is achieved by manually entering a value between the limits of 1.00 and 100.00 into data register [SP_REAL[1]], using the RSLogix Programming Software or Diagnostics SCADA/MMI graphic. Configuring the Isotope Half Life The Isotope Half Life is used to accurately calculate the decay correction between calibrations.

This variable is stored as a constant value, as its value will not be updated. The constant data file is protected from all changes via communication ports or the ladder program. Configuration of the isotope half-life must be carried out with the Processor in program mode and is achieved by manually entering a value between the limits of 1.00 and 1000.00 (years) into data register [Constant[3]], using the RSLogix Programming Software.

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Note: The default Isotope Half Life is 432.6 years, this value should not be changed unless a Tracerco engineer is consulted.

4.3 Raw Data and Weighting Factor Mapping It is important to read the Raw Data Mapping section of the FDS document, to understand how data from Detector ‘A’ and Detector ‘B’ is passed into a single file. Unmapped Raw Count Data Locations It is possible to view the raw ModBus data prior to the mapping sequence. The raw data values extracted from Detector ‘A’ and Detector ‘B’ can be observed within the software. The mapped data is displayed in [C] data array. Weighting Factor Data Locations Weighting Factor data is stored in WF. The data in this array will be configured by Tracerco to be specific for the profiler and should not be changed.

4.4 Density Definition Set Points The Density Definition Set Points are used to define the limits of each individual density band, relating to the various substances currently residing within the Vessel. For example, a density between the limits of 0.00 and 50, may define Gas, or a density between the limits of 1000 and 2000 may define Sand. The Density Definition set points addresses are shown in the table below:

Description Lower Band Upper Band

Density Band of Gas [SP_REAL[30]] [SP_REAL[31]]

Density Band of Foam [SP_REAL[32]] [SP_REAL[33]]

Density Band of Oil [SP_REAL[34]] [SP_REAL[35]]

Density Band of Emulsion [SP_REAL[36]] [SP_REAL[37]]

Density Band of Water [SP_REAL[38]] [SP_REAL[39]]

Density Band of Sand [SP_REAL[40]] [SP_REAL[41]]

Note: The Upper Set-point register is copied to the Upper Band register, therefore the values will be identical.

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The maximum upper limit for all densities stored within [CONSTANT[6]] has a default value of 10000 g/ml, as it is not possible to have a value greater than the upper density band for Sand.

Maximum Upper Limit (Set Point) The upper limit for all density bands needs to be verified to ensure the value cannot be modified to a value:

1. Greater than the maximum upper limit for all densities [CONSTANT[6]]. 2. Greater than the next set point. If a set point value is entered (i.e. upper Gas) which is greater than the next set point (i.e. upper Foam) then 0.02 will subtracted from the upper Foam set point until it is less than the upper Gas set point, thus continuously providing valid density bands.

Minimum Lower Limit Test It is only necessary for the User to enter the upper set point for each density definition (apart from Sand) as a value of 0.001 is then added to the upper band to provide the lower band for the next density definition. The lower band for each density definition (apart from Gas) is therefore equal to the upper band of the previous density definition plus 0.001. The upper band for each density definition (apart from Sand) is equal to the upper density set point. As the lower density band for Gas is permanently set to 0.00 kg/m3 and the minimum increment between each density band is 0.001.

Set Point Concurrency The limits of each density set point are constantly validated to ensure no overlapping or out of range values exist. If a set point value is entered (i.e. upper Gas) which is greater than the next set point (i.e. upper Foam) then 0.00002 will subtracted from the upper Foam set point until it is less than the upper Gas set point, thus continuously providing valid density bands.

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Note: Care must be taken as the 6 set points define the boundaries of many calculations, including the calculation to works out the interface levels as a percentage of the instrument height, percentage of the instrument volume or as a value corresponding to the Vessel (as engineering units or allowing for spacing at the top / bottom of the instrument). This consequently determines the value of the analogue outputs.

4.5 Accumulating Raw Counts This software sequence will enable the user to accumulate Raw Count data over a given time period, known as the Extended Counting Period (ECP). After the (ECP) has expired, the user will have the ability to accept the existing the Raw Count data, or save the recently accumulated Raw Count data, when performing a Background, Reference (Empty) or Reference (Density) calibration.

Configuring the Extended Counting Period The (ECP) Extended Counting Period is common to all methods of calibration.

Configuration of the Extended Counting Period is achieved by manually entering a value between the limits of 1 and 2000 (seconds) into data register [SP_WORD[10]], using the RSLogix Programming Software.

Starting the Sequence Once the ECP set point has been entered, and the Vessel has been placed into the correct state, the process of accumulating raw data can begin. To start the accumulation of data set bit [SP_BIT[5]] to a value of 1 using the RSLogix Programming Software or Accumulate Counts SCADA/MMI graphic. When the sequence has started the value previously entered into the Extended Counting Period will also be copied into the Extended Counting Period Timer before counting down until the value reaches zero. Note: The PLC will automatically reset the accumulate counts bit after the sequence has started.

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4.6 Calibration Procedures Although there are three forms of calibration required in order to successfully operate the software in normal mode they effectively work as a group. This means that if the user accumulates new Raw Counts, then the data for all forms of calibration must be saved or accepted allowing re-calculation of the calibration data.

Calibration Status Registers All forms of calibration i.e. Background, Reference (Empty) and Reference (Density) have a status register that defines the current status of the related calibration data.

These registers are known as the Background calibration status, Reference (Empty) calibration status and the Reference (Density) Calibration Status Registers, the addresses of which are shown below:

Address Description

[STATUS_Word[30]] Background calibration status register

[STATUS_Word[31]] Reference (Empty) calibration status register

[STATUS_Word[32]] Reference (Density) calibration status register

Viewing the value within each of the Calibration Status Registers reflects the status of the calibration data for each form of calibration. This is achieved using either the RSLogix Programming Software or any of the calibration SCADA/MMI graphics. The three possible states of calibration are shown below:

Value Status SCADA/MMI LED

1 No valid total count data Red

2 Total count data saved or accepted – Recalculation required Amber

3 Total count data valid – Normal Operation resumed Green

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Initiating the Calibration Sequence

Initiating a calibration will set the three Calibration Status Registers to a value of 1, to indicate that none of the calibration data has yet been saved or accepted. It will only be possible to save or accept calibration data when the system is in Calibration Mode. To initiate a calibration set bit [SP_Bit[10]] to a value of 1 using the RSLogix Programming Software or any of the calibration SCADA/MMI graphics.

Note: The PLC will automatically reset the initiate calibration bit when in Calibration Mode. Once Calibration Mode has been initiated then the calculations relating to the final density value will be inhibited. Normal Operation will only be re established when all calibration calculations are complete.

Performing a Background Calibration Background count rates should be gathered while the Vessel is full of a known substance such as Oil or Water, and the sources are either isolated or removed.

Saving Accumulated Counts to the Total Counts If the recently Accumulated Raw Count data has been gathered for Background Calibration, and it is necessary to retain this information, then the data can be saved. To save the Accumulated Raw Count data as raw Background Counts, then set bit [SP_Bit[11]] to a value of 1 using the RSLogix Programming Software or Background Calibration SCADA/MMI graphic.

Accepting the Current Total Counts If the recently Accumulated Raw Count data has been gathered for Background Calibration, and it is not necessary to retain this information, then the Current Total Count Data can be accepted in its current form.

To accept the Current Total Count Data and ignore the recently Accumulated Raw Counts, then set bit [SP_Bit[12]] to a value of 1 using the RSLogix Programming Software or Background Calibration SCADA/MMI graphic. Manual Adjustment of the Current Total Counts In Calibration Mode, it is possible to manually adjust the Total Count Data before the values are accepted. This is achieved by manually entering the required Total Count values into the [T ] data file, using the RSLogix Programming Software or Background Calibration SCADA/MMI graphic. The individual tube numbers are identical to the data word numbers to which the modified values must be written, i.e. the Background Total Count for Detector tube 48, is stored within [T_[48]].

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Performing a Reference (Empty) Calibration Reference empty count rates should be gathered while the Vessel is empty and the sources are exposed.

Saving Accumulated Counts to the Total Counts If the recently Accumulated Raw Count data has been gathered for Reference (Empty) Calibration, and it is necessary to retain this information, then the data can be saved. To save the Accumulated Raw Count data as raw Reference (Empty) Counts, then set bit [SP_Bit[13]] to a value of 1 using the RSLogix Programming Software or Reference (Empty) Calibration SCADA/MMI graphic.

Accepting the Current Total Counts If the recently Accumulated Raw Count data has been gathered for Reference (Empty) Calibration, and it is not necessary to retain this information, then the Current Total Count Data can be accepted in its current form. To accept the Current Total Count Data and ignore the recently Accumulated Raw Counts, then set bit [SP_Bit[14]] to a value of 1 using the RSLogix Programming Software or Reference (Empty) Calibration SCADA/MMI graphic.

Manual Adjustment of the Current Total Counts In Calibration Mode, it is possible to manually adjust the Total Count Data before the values are accepted. This is achieved by manually entering the required Total Count values into the [T_] data file, using the RSLogix Programming Software or Reference (Empty) Calibration SCADA/MMI graphic. The individual tube numbers are identical to the data word numbers to which the modified values must be written, i.e. the Reference (Empty) Total Count for Detector tube 48, is stored within [T_[48]]. Performing a Reference (Density) Calibration Raw Reference (Density) counts are gathered while the Vessel is full of a known substance, which is normally Water. While under calibration, the sources are exposed.

Saving Accumulated Counts to the Total Counts If the recently Accumulated Raw Count data has been gathered for Reference (Density) Calibration, and it is necessary to retain this information, then the data can be saved. To save the Accumulated Raw Count data as raw Reference (Density) Counts, then set bit [SP_Bit[15]] to a value of 1 using the RSLogix Programming Software or Reference (Density) Calibration SCADA/MMI graphic.

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Accepting the Current Total Counts If the recently Accumulated Raw Count data has been gathered for Reference (Density) Calibration, and it is not necessary to retain this information, then the Current Total Count Data can be accepted in its current form.

To accept the Current Total Count Data and ignore the recently Accumulated Raw Counts, then set bit [SP_Bit[16]] to a value of 1 using the RSLogix Programming Software or Reference (Density) Calibration SCADA/MMI graphic.

Manual Adjustment of the Current Total Counts In Calibration Mode, it is possible to manually adjust the Total Count Data before the values are accepted. This is achieved by manually entering the required Total Count values into the [T] data file, using the RSLogix Programming Software or Reference (Empty) Calibration SCADA/MMI graphic. The individual tube numbers are identical to the data word numbers to which the modified values must be written, i.e. the Reference (Empty) Total Count for Detector tube 48, is stored within [T[48]].

Recalculation of Calibration Data The recalculation sequence is the last process to be executed before Normal Operation resumes and the density calculations re-commence. The sequence involves recalculating data from the calibration period using the calculations described in the FDS document. When in Calibration Mode and the data is either saved or accepted for all forms of calibration, the Calibration Status Registers described in section 0 will have a status of 2. Only when all of the Calibration Status Registers are equal to 2, will the recalculation sequence be enabled.

Once the recalculation sequence has been enabled then it can be executed by setting bit [SP_Bit[17]] to a value of 1 using the RSLogix Programming Software or any of the calibration SCADA/MMI graphics. Once recalculation has been successfully completed then the Calibration Status Registers will be set to a value of 3, which will indicate to the return to Normal Operation.

Manual Adjustment of K Factors The K Factors calculated during the calibration sequence may be modified during Normal Operation or during calibration, however it is best to make any adjustments during Normal Operation, as once a recalculation sequence is executed, all K Factors will be updated by the recalculation routine.

The adjustment of K Factors is achieved by manually entering the required K Factor into the [K1_Constants] data file, using the RSLogix Programming Software or Reference (Density)

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Calibration SCADA/MMI graphic. The individual tube numbers are identical to the data word numbers to which the modified values must be written, i.e. the K Factor for Detector tube 48, is stored within [K1_[48]].

Configuring the Density Value The Density Value is only used when calculating K Factors, during the recalculation sequence, therefore changing this value during Normal Operation will have no effect until the next calibration has completed.

Configuration of the Density Value is achieved by manually entering a value between the limits of 0.00 and 10.00 (g/mltr) into data register [SP_Real[12]], using the RSLogix Programming Software or Reference (Density) Calibration SCADA/MMI graphic.

4.7 Alarm Configuration

Detector Tube Alarms Each individual Detector tube for a configured system has an associated Detector tube fault that is activated when a number of consecutive readings associated with the tube are registered as invalid. The Alarm Density Set Point is defined within the PLC processor software. This value is compared to the current Raw Count for each system Detector tube. If the count from the given tube is less than the Alarm Density Set Point, then a value of 1 is added to the corresponding Detector Tube Fault Count.

The Detector Tube Fault Counts are stored within data file [Tube_Alarm], the individual Detector tube numbers are identical to the data word numbers where each fault count is stored, i.e. the fault count for Detector tube 1, is stored within register [Tube_Alarm[1]]. Configuring the Alarm Density Set Point Configuration of the Alarm Density Set Point is achieved by manually entering the required value into data register [SP_Word[30]], using the RSLogix Programming Software.

Configuring the Detector Tube Number of Faults Limit The Detector tube number of faults limit is a calculated value determined by multiplying the Update Interval by 5000 msec.

Constant time period /

Update Interval (X10).

= Number of faults limit

5000 / SP_Word[1] = DTA_CFT.PRE

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Detector Tube Alarm Counter The Detector Tube Alarm Counter [STATUS_Word[52]] is used to keep track of the number of tube alarms currently in fault.

Alarm Compensation If the faulty detector tube is located at the extreme top or bottom of the range of valid detector tubes then the count value held will be replaced by the value held in relation to the adjacent detector. If a faulty detector tube is located within the array and is not located at the extreme top or bottom of the configured range, then an average of the two adjacent values will be taken and used to replace the density value within the Tracerco ProfilerTM . ModBus Communication Port Failure Alarms Each of the ModBus Nodes, has an associated communications port fault which is activated when the Raw Count values have not updated for a specified time period. The Detector Status Word for each Node is continuously monitored and compared to its previous value. Each time the Detector Status Word is updated, the value is moved to another data register and becomes the value to which the new status word is compared. For each successful update of the Raw Count data, a bit is pulsed within the software for each Node to indicate the data has refreshed. These bits are known as the Detector ‘A’ Changed Flag [STATUS_Bit[18]] Detector ‘B’ Changed Flag [STATUS_Bit[19]]. If the Detector ‘A’ Changed Flag does not change, then the ModBus Port ‘A’ Fault Timer is started, when the timer has expired the ModBus Port ‘A’ Fault Alarm is enabled at [STATUS_Bit[16] If the Detector ‘B’ Changed Flag does not change, then the ModBus Port ‘B’ Fault Timer is started, when the timer has expired the ModBus Port ‘B’ Fault Alarm is enabled at [STATUS_Bit[17]]. Configuring the ModBus Port Fault Timers The ModBus Fault Time Period is a calculated value determined by multiplying the Update Interval by a constant value.

Update Interval * Constant

value = ModBus

Fault Time Period

SP_REAL[0] * X = N54:02

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The ModBus Fault Time Period is always a multiple of the Update Interval, configuration is achieved by manually entering the required constant, using the RSLogix Programming Software. The value resulting from the multiply calculation becomes the ModBus fault time period is stored within data register [N54:02]. The ModBus Fault Time Period is then moved into the individual timer presets for each Detector Node, these are [T52:00.PRE] for Detector ‘A’ and [T52:01.PRE] for Detector ‘B’. Note: The value entered should be between the limits of 15 and 45 seconds. Values outside these limits will be automatically corrected. Always verify any new configuration using a calculator before adjusting data values within the software. Interface Alarms Interface Alarms indicate whether the percentage for a user selected density band is outside a pre configured level set point. Interface Alarms will only operate when the system is in Normal Operation. As there are 16 Digital Output Channels available per PLC system, 8 Channels will be configured for Low Level Alarms with the remaining 8 Channels configured for High Level Alarms. The Alarm Condition must exist for 2 seconds before the alarm is generated. Interface Alarms must be reset via the Alarm Reset Flag [SP_BIT[0]]. General Alarm The General Alarm Flag [STATUS_BIT[65]] is enabled when any of the following alarm conditions are enabled: • Any Detector Tube Alarm • ModBus Port ‘A’ Alarm • ModBus Port ‘B’ Alarm

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Global Alarm Reset Alarms can only be reset through manual intervention. The user will be able to reset the all system alarms using any one of two possible methods. 1. Method 1 allows the User to select the Alarm Reset Button at the MMI/SCADA

system. 2. Method 2 requires the User to go online to the PLC processor and toggle the Alarm

Reset Bit [SP_BIT[0]]. On alarm reset the following conditions will be cleared: • The Detector Tube Alarm Counter • All Detector Tube Alarms • The Detector Tube Alarm Indicator Flag • ModBus Port ‘A’ Alarm • ModBus Port ‘B’ Alarm • The Interface Alarm Indicator Flag • The General Alarm Flag • All Low and High Interface Alarms Note: Performing an alarm reset not only clears the Detector Tube Alarms from file [Tube_Alarm] but also clears the Detector Tube Alarm Counts from file [Tube_Alarm_Count] by setting all values to zero. Detector Tube Alarms can only be reset once the alarm condition has cleared. After a reset has been performed all Detector Tube Alarms that are still active will reappear instantaneously, ModBus Communication Port Failure Alarms will reappear after the ModBus Fault Time Period has expired.

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4.8 Analogue Output Outputs are represented as a value corresponding to the Vessel, displayed as either a percentage Height or Engineering Units. Interface Level Display Registers The following reference table is used to indicate the addresses [Local:6:O.Ch0Data to Local:6:O.Ch3Data] used to store the current interface levels.

The PLC control system can be configured to house an analogue output card, the

configuration of which can be 0 to 20mA, 4 to 20mA or 0 – 10V DC Output.

A number of registers exist in Tag Name [SP_Word: 60 to 65], The number of

registers used depends on the number of analogue outputs required. These

registers will be known as the analogue output selection registers.

The user will have the ability to enter any value into the analogue output selection

registers, however only values between 0 and 6 are valid as shown below:

Selection Description

<= 0 Applies a Constant 4mA to the Selected Channel

1 Selects the Gas Interface Level for Analogue Scaling

2 Selects the Foam Interface Level for Analogue Scaling

3 Selects the Oil Interface Level for Analogue Scaling

4 Selects the Emulsion Interface Level for Analogue Scaling

5 Selects the Water Interface Level for Analogue Scaling

6 Selects the Sand Interface Level for Analogue Scaling

The user can configure any combination of the analogue output selection

registers even duplicating the selection across more than one output i.e. all

analogue output selection registers could be set to 1.

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To configure the Channel scaled minimum and maximum operating range, user can

define selection of range in Percentage (%) by keying information in registers exist

into Tag Name as shown below:

SP_Real Description

SP_Real[50/51] Selects the Gas Interface Level for Analogue Scaling

SP_Real[52/53] Selects the Foam Interface Level for Analogue Scaling

SP_Real[54/55] Selects the Oil Interface Level for Analogue Scaling

SP_Real[56/57] Selects the Emulsion Interface Level for Analogue Scaling

SP_Real[58/59] Selects the Water Interface Level for Analogue Scaling

SP_Real[60/61] Selects the Sand Interface Level for Analogue Scaling

4.9 Digital Output (If fitted) The digital output card is normally configured to give a system healthy indication.

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5. Maintenance

The following section is concerned with the maintenance of the Tracerco ProfilerTM . Because there are no moving parts or routine checks this section is mainly devoted to the solving of faults that could occur. As this may mean some disconnection of the system you will find wiring information here. But beware, this is an Intrinsically Safe system. After any work on the system, it must be left in the exactly the same condition as it was when commissioned. All wiring on the hazardous side of the Galvanically Isolated power supplies must conform to the system wiring diagram certified by BASEEFA. The construction of the profiler after any repair must always conform to the Apparatus Certificate issued by BASEEFA. Any repair to the system must be carried out by people qualified in this area. They must have the knowledge necessary for this work. We advise that repairs be made by Tracerco Services engineers.

5.1 Wiring and hook-up description – The power supply to the Profiler

Connection in the safe area Each power supply to the Tracerco Profiler are independent of the other. Each is Intrinsically Safe and comes from a Pepperl + Fuchs Isolating Power Supply unit (KFD2-SD-Ex1.10100) mounted in the safe area. These units can supply up to 100mA at 10VDC. They are in the bottom of the free standing cabinet. They are identified with the plant ID (loop/tag number) and marked `A’ and `B’ to correspond with the Signal Processor (`A’ and `B’) they are connected to, if applicable. The supply is via a two core screened cable with an outer armour. At the Isolator, the armour will not be connected, not even to ground. It will be insulated. The 0V and drain wires of the screen are connected to pin 2 on the isolator. The +ve supply is connected to pin 1. Connection at the vessel The armour will be connected to the neck plate and terminated there so that any RF pick-up on it is not radiated into the dome. The inner insulation carries through the neck plate to the gland plate of the Signal Processor. Here, there is a Warth International cable feed-through gland. Enough cable must be present between the two glands to allow the Signal Processors to swing away from the neck so access is possible to the probes and source assembly. Bare about 15mm of screen to allow the shielding seal (in the gland at the Signal Processor gland plate) to make contact.

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The insulated and screened two core carries on to the Power-in connector. Before connection is made to this two-part connector, the ferrite bead must be slipped in place (as shown on the drawing) and insulated with amalgamating tape. Strip the end of the cable for connection to the connector and sleeve the screening. Take the 0V and screen drain wire (sleeved) to terminal 4 on the Power in connector. This terminal is not identified but is the most left terminal and is shown clearly on the Systems Diagram. The +ve wire is connected to terminal 2 (second from the right)

5.2 Wiring and hook-up description – The optical cable connection Information transmission between the Profiler and the PLC (in the safe Area) is by fibre optic cable. There are receive and transmit lines between each independent half of the profiler and the PLC. The optical cables are connected as shown in the hook-up diagram. ST connectors are to be used at both the fibre driver and Tracerco ProfilerTM PCB end of the optical cable. Connection within the breakout box is achieved by splicing the cables or using a suitable adapter and connectors (ST connectors are recommended). Only one adapter between Fibre Driver and the Tracerco ProfilerTM is to be used. Note that a transmit signal Tx on the PCB is connected to the receive signal Rx on the fibre driver, and visa versa for receive Rx on the PCB connects to Transmit Tx on the driver. Each connector has a label on denoting whether it is Rx or Tx. Probe A is connected to FOC1 and data is sent via Modbus protocol to the Allen Bradley Probe B is connected to FOC2 and data is sent via Modbus protocol to the Allen Bradley The armoured cable must not be connected to the metalwork of the Tracerco ProfilerTM , and the armouring should not protrude through the cable gland into the dome. It should be cut off at the cable gland to prevent RF signals radiating into the dome.

5.3 Intrinsic Safety considerations The introduction to this section emphasises the constraints placed on modifications/repairs to this Intrinsically Safe system. If work on the system is unavoidable then the following points should be considered. • The electrical connection to the Tracerco ProfilerTM must conform to the “Systems

Diagram for Hazardous Areas” drawing. This drawing is appended.

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• The practical route to conforming with the above is described in the ‘Density Profiler System Hook-up’ drawing. If connections need to be made, then this drawing must be followed. The drawing also shows the screening method necessary for the system to conform to the EEC directive on Electromagnetic Compatibility.

• The manufacturer should only make repairs to the Printed Circuit Boards of the Tracerco

ProfilerTM (the hazardous area part). Any deviation from the production standard is forbidden in law. Even applying a soldering iron to a joint can leave the board in a condition that invalidates the certificate.

• Changing the Signal Processor PCB is possible provided it is a straight forward swap

and the wiring diagrams are followed but any other PCB exchanges are not possible. For anything more than the Signal Processor PCB exchange please contact Tracerco services.

5.4 Safety/handling precautions Precautions on vessel entry will involve the isolation of the sources. This is explained in the appended local rule under sections Source Isolation, Labelling, Designated Areas, Failure of Shutter to isolate the Arming Rod prior to Vessel entry and Physical Damage (internal) Take care in the area of the dip pipes when working in the vessel. These have 2mm thick titanium walls and any indents would make removal of the source rod or probes difficult. For removal of the Arming Rod assembly refer to the section in the appended local rule under the heading Source Security. The assembly is heavy and will require two people to handle it. When removing the probes from the dip pipes take great care not to bend them. If they are inadequately supported they bend easily under their own weight to the point where damage may occur. For this reason we recommend securing the probes to a suitable support (e.g. length of angle iron) which will facilitate safe handling. 5.5 Fault Location If an error has occurred somewhere in the system, there are several indicators to a problem. The main indicator is on the DCS operator screen, a more detailed investigation can be performed on the PLC. Please refer to the PLC manual. The Tracerco ProfilerTM produces a global error if any errors occur in the Profiler. This alarm should be indicated on the DCS and is the primary indicator of an error in the Tracerco ProfilerTM

PLC orTracerco ProfilerTM Error

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If any error occurs in the software, communications between the Tracerco ProfilerTM and the PLC, a detector fails or a particular tube fails. Then a general alarm flag is set in the PLC and this is flagged up on the DCS screen. The “ERROR” flag on the DCS screen will change to show that an error has occurred in the PLC or Tracerco ProfilerTM. To diagnose the problem you must check the PLC is working correctly Figure 1. This involves checking the PLC hardware for power, current mode etc

Figure 1

PLC Fault

Is the Run light

on PLC Software and Go ON

LINE

Is the Fault

LED on

Is PLC Power

on

Error Indicated

If the PLC appears to be working with no hardware faults. You must check the software to find the problem. Interrogate the PLC and diagnose what is causing the problem. Alarm Flag Values These alarms can indicate the following :-

1. Indicate the loss of a tube, ie no counts. 2. Loss of comms with probe A.

3. Loss of comms with probe B.

4. Global alarm indicating a PLC failure.

For more information on resetting these alarms please refer to the plc manual.

5.6 Routine maintenance/inspection There is no routine maintenance. The installation requires a monthly inspection to confirm the presence of the sources, warning signs and source shutter position indicators.

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6 Scada System

Stand-Alone versions of the Profiler are provided with Labview system for visualisation of the profiler systems. Profiler specific information is provided within the following section. Screens shown are generic and the actual implementation will vary, the information within this section is also useful for other DCS and SCADA systems.

6.1 Installing New Application Tracerco can update the Labview application if required. The new application will be supplied on a CD-Rom. To install application place CD in to drive and follow installation set up. To install the calibration software insert CD and highlight calibration software and follow set up procedure. To start the application, press C: \ PROGRAMS\ TRACERCO PROFILER once completed the below page will be displayed.

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6.2 Overview This is the initial graphic for the display and shows an overview of densities and levels on all vessels.

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6.3 Vessel Overview The vessel overview screen shows both visually and numerically the levels of the various phases within the vessel. If more than one profiler is connected to the standalone system, then access buttons are available at the bottom of the screen. In the event of a fault with the profiler a red box will appear around the vessel to indicate that a fault has occurred.

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6.4 Diagnostics Screen The Diagnostics Screen shows the raw counts for each detector with the calculated density at each point. This screen is useful for detector tube fault diagnosis.

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6.5 Trending Display

The Trending Display shows the levels of all six phases over the previous hour.

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6.6 Profile Screen The Profile Screen shows the densities going down the vessel, if the density band set points are set correctly the phases will be shown in their relevant colour.

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6.7 Setpoints The setpoint screen shows the operator the density setpoints, update period, filter factor and level setpoints. From this screen it is not possible to change any of the values. By logging on using the supervisor account a button appears on the screen at the bottom which is marked with change setpoints, this screen takes you through to a screen which does allow to adjust the settings.

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6.8 PLC Status Screen In normal operation the Watch Dog on the status screen will change value approximately every 2 seconds. If the value does not change then there is a fault with the PLC system. Other faults could occur including not being calibrated. In these cases text messages will appear on the screen indicating what the user is required to do.

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6.9 Calibration Status To start the calibration application, C:\PROGRAM FILES\PROFILER CALIBRATION after starting the below screen will be displayed.

The above enables the operator to select calibration mode and perform a calibration by obtaining new data and saving it or by accepting the current data. NOTE selecting calibration mode will stop densities and levels being calculated from the PLC, until calibration has been completed.

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6.10 Value Tables The above shows data held within registers of the PLC and is all the information required to perform a calibration. To view the data from a particular register just press the corresponding button.

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