microtech® c vintage water-cooled™ screw chiller...opm - open protocol master panel there is only...

Open Protocol Data Information Packet Version 1.2

Group: Controls

Date: December 1998

© 2002 McQuay International

MicroTech®C Vintage Water-Cooled™ Screw Chiller

Open Protocol™ Data Communications

Proprietary Information McQuay International

Version 1.2 2

- C O N F I D E N T I A L -

This Document may not be copied or reproduced in any way without the express written consent ofMcQuay International.

NOTICE

Copyright © 1998McQuay International, Minneapolis MN

All rights reserved throughout the world.

McQuay International reserves the right to change any information contained herein without priornotice. No guarantees are given as to the accuracy of information provided.

McQuay International Proprietary Information

3 Version 1.2

ContentsRevision History ................................................................................................................................... 3

Version 1.2 ........................................................................................................................................ 3Version 1.1 ........................................................................................................................................ 3Version 1.0 ........................................................................................................................................ 4

Overview.................................................................................................................................5Compatible Unit Control Software for Open Protocol.......................................................................... 5Network Configuration ......................................................................................................................... 5

Communications to a Single Chiller ................................................................................................. 5Communications to Two or More Chillers........................................................................................ 6

Supplemental Literature .......................................................................................................8Conversions and Conventions.............................................................................................9Converting 2 Byte Variables................................................................................................................. 9Note on Temperatures ........................................................................................................................... 9Note on Pressures.................................................................................................................................. 9OPM - Open Protocol Master Panel ...................................................................................10Read Only Memory Locations ............................................................................................11Read Only Memory Definitions ..........................................................................................16Read and Write Memory Locations. ..................................................................................22Read and Write Memory Definitions..................................................................................23Chilled Water Rest Options ................................................................................................254-20mA ............................................................................................................................................... 25Network............................................................................................................................................... 25OAT .................................................................................................................................................... 25Return.................................................................................................................................................. 26Required Development Testing Tools...............................................................................27Setup of Hardware for Testing............................................................................................................ 27Simulator Monitor Software Guide ....................................................................................28Overview............................................................................................................................................. 28Logging on to the software ................................................................................................................. 28Communications Initialization ............................................................................................................ 28Downloading Simulation code............................................................................................................ 30Monitoring a simulator controller ....................................................................................................... 31Support Menu - Read/Write screens ................................................................................................... 31Disabling the Simulator Control Code ................................................................................................ 33Further Information on Windows Monitor Software .......................................................................... 34Glossary of Terms ...............................................................................................................35

Revision HistoryVersion 1.2Changes to the Chilled Water Temp Setpoint / Minimum Chilled Water Temp Setpoint($0905) andhow it affects Network, Return, OA, Ice, and 4-20mA chilled water resets.Addition of Maximum Chilled Water Reset Setpoint($090C), Entering Evaporator Water Temp ResetSetpoint ($090D), Maximum Reset @ OAT ($09A8), Network Reset ($044E), OAT from BAS(0CC8),and No Reset @ OAT ($09A7)Addition of Compressor 1 Hours ($0862-$0863) and Compressor 2 Hours ($0864-$0865)Addition of Outdoor Air Temperature ($047D-E)Changes to Circuit 1 Alarms ($1C00) and Circuit 2 Alarms ($1D00)Removed Unit Operating Hours ($08F1-$08F2)Removed all memory locations involving Compressor 3 and Compressor 4

Version 1.1Changes to the Unit Status ($04CE)


Version 1.2 4

Editing changesChange of name from C Vintage Flooded™ Screw Chiller to C Vintage Water-Cooled™ ScrewChiller

Version 1.0The initial release of document.


5 Version 1.2

Overview

Compatible Unit Control Software for Open ProtocolThe McQuay Open Protocol™ for C vintage water-cooled screw chillers allows other automationintegrators to communicate with a network of chillers or a single chiller and obtain useful operatinginformation through communication "reads" to the controller. In addition, remote control of thechiller is possible by communication "writes" to the controller of new setpoints and commands.The model designation for the C Vintage water-cooled screw chiller is PFS, which is also the samefor the previous versions of the water-cooled screw chiller. It is highly recommended that to insurethat the correct software driver is used on the job-site that the software identification string is used toidentify the unit. The software identification string is a menu item on the keypad for the unit. Thefollowing table lists the valid 8 character C vintage water-cooled screw chiller open protocolcompatible idents:

Software ID String Description

FLU12033 C Vintage Flooded Screw Chiller

FLU12023 C Vintage Flooded Screw Chiller

1 This character describes the refrigerant type; 2=R22, 3=R134a, 4=R410a.2 This character describes the units (displayed on keypad only); E=English, S=SI.3 This character describes the revision number, updates do not affect open protocol. (The 03 or 02 in the ident is the version number. This usually indicates an extensive update of thesoftware. If this were 04 on site for example, the open protocol memory locations likely would havechanged. If this is the case, use McQuay Online to obtain a later release of this document.)In addition, software IDENTs are stored within the controllers in memory locations $0A08-$0A0F.The above IDENTs result when the memory locations are translated into ASCII.

Network ConfigurationThis section explains how the McQuay International Chiller Open Protocol Network works so thatyou can choose the correct equipment and program your system to communicate through McQuayInternational's MicroTech Open Protocol.There are two scenarios for connecting to the controllers that are used to make an Open ProtocolChiller Network. They are as follows:• Communications to a single chiller• Communications to two or more chillers

Communications to a Single ChillerAll McQuay MicroTech Chillers are shipped from the factory with one communications port factory-configured for RS-232, 9600 baud. The port is located on the controller and is designated Port A.The port may also be accessed via RS-485 by replacing the factory installed RS-232 plug with a RS-485 plug. The RS-485 plug may be constructed according to the Open Protocol Wiring Diagrambooklet, or may be purchased through McQuay International. The following diagram shows the chiller-to-network connections on Port B; communicationsbetween the chiller and Building Automation System (BAS) established on Port A.

Hexadecimal valuesare indicated by a

preceding ‘$


Version 1.2 6

Unit Controller (Model 250/280)

Communications to Two or More ChillersThe OPM provides a single communications port entry into the McQuay Chiller Network. The OPMpanel consists of a McQuay model 120 controller. The automation integrator connects to CommPort A, which is switch selectable to RS-232 or RS-485 communications, 9600 baud. Port A is theautomation control integrator's Open Protocol communications port. Comm Port B is a daisychained, multi-drop, 9600 baud, RS-485 proprietary McQuay protocol.The main function of the OPM is to provide the network communications interface for up to 64chiller controllers.The chiller controller is factory mounted. The unit controller provides pre-programmed, pre-engineered and pre-tested stand-alone control. There is one controller for each chiller.Once the McQuay communication network has been commissioned (by a McQuay representative,the BAS vendor can connect their Open Protocol device to the OPM. The chillers will continue tooperate when communications are lost. However, the network must be intact for read and writerequests from the BAS vendor’s communication device to be passed along to the chillers.When the BAS communicating device is connected to the OPM panel, the communicationsconfiguration is as follows:


7 Version 1.2

OPM

MC

B an

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Chi

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CB


Version 1.2 8

Supplemental Literature

It is the objective of this document to give an overview of the screw chiller and to document theavailable points offered through Open Protocol. It is strongly recommended that the followingdocumentation be used in conjunction with this document. A detailed sequence of operation isdescribed in the Operation and Maintenance (OM) manual (if available). Unit wiring details aregiven in the Installation and Maintenance manual (if available). Open Protocol wiring details anddiagrams for connectors are given in the Open Protocol Wiring Diagrams booklet. The generic OpenProtocol Data Information Packet explains the how to access information via the McQuayMicroTech protocol.

Ver 1.1 Open Protocol Data Information Packet Apr, 96OM 549 Operation Manual Jan, 97CD573875Y Open Protocol Wiring Diagrams July, 95


9 Version 1.2

Conversions and Conventions

Converting 2 Byte VariablesIn the following read only and read/write tables, a 2-byte variable address is indicated by a dash (-).The first memory location listed will always be the high byte and the second memory location listedwill be the low byte. For example, $04DB-C, $04DB is the high byte and $04DC is the low byte.Two byte variables use the following conversion unless otherwise specified:Value = HiByte*255+LoByte.The value may need to be further processed by the given conversion to get the final result in the unitsspecified.

Note on TemperaturesAll temperatures given above are in degrees Fahrenheit, to get degrees Celsius, you must use thestandard formula for temperature conversion:ºC = (5/9) * (ºF -32)

Note on PressuresAll pressures given above are in PSI, to get KPA, you must use the following standard conversion:KPA = 6.89*PSI


Version 1.2 10

OPM - Open Protocol Master Panel

There is only one memory location that can be read in the Open Protocol Master Panel. It is used toverify that the OPM is powered and communicating, and that the applications code is intact.

Open Protocol Master Status $04000-254 = Program is running255 = Program is not running


11 Version 1.2

Read Only Memory Locations

Description Address

(Hex)

Range (X) Conversion Units orDescription

Chilled Water Temperature-Active Setpoint

098C 0-160 X/2 °F

Chiller Unit Temperature Type0 = Standard1 = Low Temp

081B 0, 1

Compressor Lift Pressure 0474-0475

0-65,535 X/10 PSIG

Compressor 1 Motor Current % 04A9 0-100 Percent RLACompressor 2 Motor Current % 04AA 0-100 Percent RLACompressor 1 Operating Hours 0862-

08630-65,280 hrs

Compressor 2 Operating Hours 0864-0865

0-65,280 hrs

Compressor 1 SuctionTemperature

047F-0480

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Compressor 2 SuctionTemperature

0481-0482

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Compressor Superheat –Discharge Circuit 1

04DF-04E0

0-2,630 X / 10 ºF

Compressor Superheat –Discharge Circuit 2

04E1-04E2

0-2,630 X / 10 ºF

Compressor Superheat –Suction Circuit 1

04DB-04DC

0-2,630 X / 10 ºF

Compressor Superheat –Suction Circuit 2

04DD-04DE

0-2,630 X / 10 ºF

Condenser ApproachTemperature

04D9-04DA

0-2,630 X / 10 °F

Condenser DifferentialPressure - Liquid Line

04A1-04A2

0-65,535 X / 10 PSI

Condenser Pump Status0=Condenser Pumps Off1=Starting Condenser Pump #12=Starting Condenser Pump #23=Condenser Pump #1 On4=Condenser Pump #2 On5=Condenser Pump #1 Fail;

Starting #26=Condenser Pump #2 Fail;

Starting #17=Condenser Pumps #1 & #2 Failed

0437 0-7


Version 1.2 12

Description Address

(Hex)


Condenser Pump # 1 OperatingHours

08FA-08FB

0-49,999 hrs

Condenser Pump # 2 OperatingHours

08FD-08FE

0-49,999 hrs

Condenser RefrigerantPressure

046D-046E

0-4,50063,985 =Short61,425 =Open

X / 10 PSIG

Condenser SubcoolingTemperature

04E5-04E6

0-2,630 X / 10 ºF

Condenser Water Flow Rate 0492-0493

0-65,535 GPM

Condenser Water Flow Status0 = No Flow1 = Flow

04CF 0, 1

Condenser Water Rate Sensor0 = Not Present1 = Present

0873 0, 1

Condenser Water Temperature- Delta

04D5-04D6

0-2,630 X / 10 °F

Condenser Water Temperature- Entering

0479-047A

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Condenser Water Temperature- Leaving

047B-047C

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Cooling Tower Control0 = External1 = Chiller

0995 0, 1

Cooling Tower Stage 04B8 0-6 stagesCooling Tower Valve Position 04B9 0-100 %Discharge RefrigerantTemperature – Circuit 1

0463-0464

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Discharge RefrigerantTemperature – Circuit 2

0465-0466

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Evaporator ApproachTemperature

04D7-04D8

0-2,630 X / 10 °F


13 Version 1.2

Description Address

(Hex)


Evaporator Pump Status0=Evaporator Pumps Off1=Starting Evaporator Pump #12=Starting Evaporator Pump #23=Evaporator Pump #1 On4=Evaporator Pump #2 On5=Evaporator Pump #1 Fail;Starting #26=Evaporator Pump #2 Fail;Starting #17=Evaporator Pumps #1 & #2Failed

0436 0-7

Evaporator Pump #1 OperatingHours

08F4-08F5

0-49,999 hrs

Evaporator Pump #2 OperatingHours

08F6-08F7

0-49,999 hrs

Evaporator RefrigerantPressure

046B-046C

0-1,50063,985 =Short61,425 =Open

X / 10 = PSIG

Evaporator Water Flow Rate 0490-0491

0-65,535 GPM

Evaporator Water Flow Status0 = No Flow1 = Flow

04C2 0, 1

Evaporator Water Rate Sensor0 = Not Present1 = Present

0872 0, 1

Evaporator Water Temperature- Delta

04D3-04D4

0-2,630 X / 10 °F

Evaporator Water Temperature- Entering

0477-0478

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Evaporator Water Temperature- Leaving

0461-0462

600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F


Version 1.2 14

Description Address

(Hex)


Fault - Current Active - Circuit 10-128=None129=Liquid Line Sensor Failure130=Entering Evaporator Sensor Failure131=Leaving Condenser Sensor Failure171=Entering Evaporator Sensor Problem172=Outside Air Temperature SensorProblem173=High Condenser Pressure No Load174=High Condenser Pressure Unload175=Low Evaporator Pressure Unload176=Condenser Freeze Protect177=Evaporator Freeze Protect215=Low Evaporator Pressure Shutdown216=Low Evaporator No Start217=Low Motor Current 218=High Discharge Temperature219=High Condenser Pressure220=Mechanical High CondenserPressure221=High Motor Temperature222=Starter Fault223=No Transition224=No Evaporator Flow225=No Condenser Flow226=High Motor Current227=No Liquid Run228=No Super Heat Drop229=High Discharge Super Heat230=Evaporator Pressure Sensor Failure231=Entering Condenser Sensor FailureShut Down232=Suction Temperature Sensor Failure233=Discharge Temperature SensorFailure234=Condenser Pressure Sensor Failure235=Leaving Evaporator Sensor FailureShut Down236=Voltage Ratio Sensor Failure

1C00 0-236

Fault - Current Active - Circuit 2 1D00 0-236 Same as Circuit1

Last Start Hour 08E1 0-23 hourLast Start Minute 08E2 0-59 minuteLast Start Month 08E3 1-12 monthLast Start Date 08E4 1-31 dayLast Start Year 08E5 0-99 yearLast Stop Hour 08E6 0-23 hourLast Stop Minute 08E7 0-59 minuteLast Stop Month 08E8 1-12 monthLast Stop Date 08E9 1-31 dayLast Stop Year 08EA 0-99 yearLiquid Line RefrigerantTemperature

048D-048E

600-3,63063,985 =Short61,425 =Open

(X -1000) /10

°F


15 Version 1.2

Description Address

(Hex)


Liquid Line Pressure 046F-0470

0-4,50063,985 =Short61,425 =Open

X / 10 PSIG

Outdoor Air temperature 047D-7E 0-6,00063,985 =Short61,425 =Open

(X -1000) /10

°F

Outdoor Air TemperatureMethod0 = Not Present1 = Local 2 = Network

087C 0-2

Refrigerant Detection Sensor0 = Not Present1 = Present

0874 0, 1

Refrigerant Leak DetectionLimit

0494 0-100 PPM

Unit Status0=All Systems Off1=Off: Panel Switch2=Off: Manual3=Off:Pumpdown Switch4=Off: Ambient Lockout5=Off: Remote Communications6=Off: Remote Switch7=Off: Time Schedule8= Off: Waiting for Flood9= Start Requested10= Evaporator Pump Off11= Evaporator Pump On - Waiting forFlow12= Evaporator Pump On - Recirculate13= Evaporator Pump On - Cycle Timers14= Evaporator Pump On - Waiting forLoad15= Condenser Pump Off16= Condenser Pump On Waiting for Flow17= Cool Staging18= Manual Cool Staging19= Cool Stage Up20= Cool Stage Down21= Shut Down/Pump Down22= Condenser Pump Off Shutdown23= Evaporator Pump Off Shutdown

04CE 0-27


Version 1.2 16

Read Only Memory Definitions

Chilled Water Temperature - Active Setpoint 098CThe chilled water temperature location contains the active chilled water setpoint the unit is using fortemperature control. The active setpoint may be set by several control scenarios which are dependentupon chiller configuration parameters. A data range of 0 to 160 corresponds to the temperature rangeof 0ºF to 80ºF with 0.5ºF resolution.

Chiller Unit Temperature Type 081BUnit temperature type indicates whether the unit is a low or standard discharge temperature unit. Avalue of zero indicates a standard chiller unit; a one indicates a low temperature unit.

Compressor Lift Pressure 0474-75Lift pressure is the pressure rise of the refrigerant gas as it passes through the compressor. Liftpressure is calculated by subtracting evaporator refrigerant pressure from the condenser refrigerantpressure. The BAS integrator should assume this value will always be valid. The resolution of thevalue is 0.1 PSIG.

Compressor 1 Motor Current Percent 04A9Compressor 2 Motor Current Percent 04AAMotor current holds the percent of rated load AMPs of each compressor.

Compressor 1 Operating Hours 0862-63Compressor 1 Operating Hours stores the number of hours compressor 1 has run. These locationscontain valid data when in the range of 0 and 65,280. The value will roll over to 0 once the 65,280hour has been completed.

Compressor 2 Operating Hours 0864-65Compressor 2 Operating Hours stores the number of hours compressor 2 has run. These locationscontain valid data when in the range of 0 and 65,280. The value will roll over to 0 once the 65,280hour has been completed.Compressor 1 Suction Temperature 047F-80 Compressor 2 Suction Temperature 0481-82 Suction temperature is the temperature of the refrigerant gas entering each compressor. The datarepresents a valid temperature only if the resultant value is between -40°F and 263°F. The resolutionof the value is 0.1°F.

Compressor Superheat – Discharge Circuit 1 04DF-E0 Compressor Superheat – Discharge Circuit 2 04E1-E2Discharge superheat is the temperature difference between the refrigerant gas leaving the compressorand the refrigerant phase change temperature point. It is derived by subtracting a calculatedcondenser refrigerant phase change temperature from discharge refrigerant temperature. The datarepresents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution ofthe value is 0.1°F.

Compressor Superheat – Suction Circuit 1 04DB-DC Compressor Superheat – Suction Circuit 2 04DD-DESuction superheat is the temperature difference between the refrigerant gas entering the compressorand the refrigerant phase change temperature point. It is derived by subtracting a calculatedevaporator refrigerant phase change temperature from the compressor suction temperature. The datarepresents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution ofthe value is 0.1°F.

Condenser Approach Temperature 04D9-DAThe approach temperature is the difference in temperature between the condenser refrigerant and thecondenser leaving water. It is calculated by subtracting leaving condenser water temperature fromcondenser refrigerant temperature. The data represents a valid temperature only if the resultant valueis between 0°F and 263°F. The resolution of the value is 0.1°F.


17 Version 1.2

Condenser Differential Pressure - Liquid Line 04A1-A2This differential pressure is the difference between the condenser and the liquid line in PSI.

Condenser Pump Status 0437Pump status stores the operating status of the condenser water pumps.

Condenser Pump #1 Operating Hours 08FA-FBPump #1 operating hours stores the number of hours condenser pump #1 has run. These locationscontain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999hour has been completed.

Condenser Pump #2 Operating Hours 08FD-FEPump #2 operating hours stores the number of hours condenser pump #2 has run. These locationscontain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999hour has been completed.

Condenser Refrigerant Pressure 046D-6ERefrigerant pressure is the pressure of the refrigerant gas in the condenser shell. The data representsa valid pressure only if the resultant value is between 0 and 450 PSIG. The resolution of the value is0.1 PSIG.

Condenser Subcooling Temperature 04E5-E6Subcooling is the temperature difference between the liquid refrigerant leaving the condenser and therefrigerant phase change temperature point. It is derived by subtracting the liquid line refrigeranttemperature from a calculated condenser refrigerant phase change temperature. The data represents avalid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is0.1°F.

Condenser Water Flow Rate 0492-93Water flow rate stores the rate of water flowing through the condenser tubes. The resolution for thisvalue is 1 GPM and the range is dependent on the condenser flow sensor. If a condenser flow ratesensor is present the data will always be valid.

Condenser Water Flow Status 04CFThe value in the condenser water flow status location indicates the position of the condenser waterflow switch. A zero indicates no water flow through the condenser; a one indicates water movement.

Condenser Water Rate Sensor 0873The value in the condenser water rate sensor location indicates whether a condenser flow rate sensoris connected to the unit. A zero indicates a sensor is not present; a one indicates a sensor is present.Condenser water flow rate data is valid only when this sensor is present.

Condenser Water Temperature - Delta 04D5-D6The delta temperature is the difference between the entering and leaving condenser watertemperatures. The value is calculated by subtracting entering condenser water temperature fromleaving condenser water temperature. The data represents a valid temperature only if the resultantvalue is between 0°F and 263°F. The resolution of the value is 0.1°F.

Condenser Water Temperature - Entering 0479-7AEntering water temperature is the temperature of the water entering the condenser. The datarepresents a valid temperature only if the resultant value is between -40°F and 263°F. The resolutionof the value is 0.1°F.

Condenser Water Temperature - Leaving 047B-7CLeaving water temperature is the temperature of the water leaving the condenser. The watertemperature is measured with a 0.1°F resolution. The data is valid only if the resultant temperature isbetween -40°F and 263°F.

Cooling Tower Control 0995The value in the cooling tower control location indicates whether cooling tower functions are beingcontrolled by the chiller unit or an external control system. A zero indicates that an external system isbeing used; a one indicates that the chiller is providing control. Cooling tower data points are onlyvalid when the chiller is in control.


Version 1.2 18

Cooling Tower Stage 04B8The value in the cooling tower stage location indicates the number of cooling tower stages that areenergized. The data is valid only if tower control is provided by the chiller. The valid range is 0 to 6.

Cooling Tower Valve Position 04B9The valve position location stores the position of the cooling tower valve. The position is measuredas a percent of full open and has a 1% resolution. The data is valid only if tower control is providedby the chiller. The valid range is 0-100%.

Discharge Refrigerant Temperature – Circuit 1 0463-64Discharge Refrigerant Temperature – Circuit 2 0465-66Discharge refrigerant temperature is the temperature of the compressor refrigerant gas as it leaves thecompressor. The data represents a valid temperature only if the resultant value is between -40°F and263°F. The resolution of the value is 0.1°F.

Evaporator Approach Temperature 04D7-D8The approach temperature is the difference in temperature between the evaporator refrigerant and theevaporator leaving water. It is calculated by subtracting evaporator refrigerant temperature fromleaving evaporator water temperature. The data represents a valid temperature only if the resultantvalue is between 0°F and 263°F. The resolution of the value is 0.1°F.

Evaporator Pump Status 0436Pump status stores the operating status of the evaporator water pumps.

Status Value

Evaporator Pumps Off 0

Starting Evaporator Pump #1 1

Starting Evaporator Pump #2 2

Evaporator Pump #1 On 3

Evaporator Pump #2 On 4

Evaporator Pump #1 Fail; Starting #2 5

Evaporator Pump #2 Fail; Starting #1 6

Evaporator Pumps #1 & 2 Failed 7

Evaporator Pump #1 Operating Hours 08F4-F5Pump #1 operating hours stores the number of hours evaporator pump #1 has run. These locationscontain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999hour has been completed.

Evaporator Pump #2 Operating Hours 08F6-F7Pump #2 operating hours stores the number of hours evaporator pump #2 has run. These locationscontain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999hour has been completed.

Evaporator Refrigerant Pressure 046B-6CRefrigerant pressure is the pressure of the refrigerant gas in the evaporator shell. The data representsa valid pressure only if the resultant value is between 0 and 150 PSIG. The resolution of the value is0.1 PSIG.

Evaporator Water Flow Rate 0490-91Water flow rate stores the rate of water flowing through the evaporator tubes. The resolution for thisvalue is 1 GPM and the range is dependent on the evaporator flow sensor. If an evaporator flow ratesensor is present the data will always be valid.

Evaporator Water Flow Status 04C2The value in the evaporator water flow status location indicates the position of the evaporator waterflow switch. A zero indicates no water flow through the evaporator; a one indicates water movement.


19 Version 1.2

Evaporator Water Rate Sensor 0872The value in the evaporator water rate sensor location indicates whether an evaporator flow ratesensor is connected to the unit. A zero indicates a sensor is not present; a one indicates a sensor ispresent. Evaporator water flow rate is only valid when this sensor is present.

Evaporator Water Temperature - Delta 04D3-D4Water temperature delta is the difference between the entering and leaving evaporator watertemperatures. The value is calculated by subtracting evaporator leaving water temperature fromentering evaporator water temperature. The data represents a valid temperature only if the resultantvalue is between 0°F and 263°F. The resolution of the value is 0.1°F.

Evaporator Water Temperature - Entering 0477-78Entering water temperature is the temperature of the water entering the evaporator. The datarepresents a valid temperature only if the resultant value is between -40°F and 263°F. The resolutionof the value is 0.1°F.

Evaporator Water Temperature - Leaving 0461-62Leaving water temperature is the temperature of the water leaving the evaporator. The watertemperature is measured with a 0.1°F resolution. These locations contain valid data only if theresultant temperature is between -40°F and 263°F.

Fault - Current Active – Circuit 1 1C00Fault - Current Active – Circuit 2 1D00The fault location holds the current unit fault. If multiple faults should occur, the most serious faultwill be stored in this location.

Fault Condition ValueNone 0-128Liquid Line Sensor Failure 129Entering Evaporator Sensor Failure 130Leaving Condenser Sensor Failure 131Entering Evaporator Sensor Problem 171Outside Air Temperature Sensor Problem 172High Condenser Pressure No Load 173High Condenser Pressure Unload 174Low Evaporator Pressure Unload 175Condenser Freeze Protect 176Evaporator Freeze Protect 177Low Evaporator Pressure Shutdown 215Low Evaporator No Start 216Low Motor Current 217High Discharge Temperature 218High Condenser Pressure 219Mechanical High Condenser Pressure 220High Motor Temperature 221Starter Fault 222No Transition 223No Evaporator Flow 224No Condenser Flow 225High Motor Current 226No Liquid Run 227No Super Heat Drop 228High Discharge Super Heat 229Evaporator Pressure Sensor Failure 230Entering Condenser Sensor Failure Shut Down 231Suction Temperature Sensor Failure 232Discharge Temperature Sensor Failure 233


Version 1.2 20

Fault Condition ValueCondenser Pressure Sensor Failure 234Leaving Evaporator Sensor Failure Shut Down 235Voltage Ratio Sensor Failure 236Last Start Hour 08E1The start hour location stores the hour value corresponding to the last time the unit started in militarytime.

Last Start Minute 08E2The start minute location stores the minute value corresponding to the last time the unit started.

Last Start Month 08E3The start month location stores the month value corresponding to the last time the unit started. Thevalue 1 corresponds to the month of January.

Last Start Date 08E4The start date location stores the date value corresponding to the last time the unit started. The value1 corresponds to the first day of the month.

Last Start Year 08E5The start year location stores the last two digits of the year corresponding to the last time the unitstarted.

Last Stop Hour 08E6The stop hour location stores the hour value corresponding to the last time the unit stopped inmilitary time.

Last Stop Minute 08E7The stop minute location stores the minute value corresponding to the last time the unit stopped.

Last Stop Month 08E8The stop month location stores the month value corresponding to the last time the unit stopped. Thevalue “1” corresponds to the month of January.

Last Stop Date 08E9The stop date location stores the day value corresponding to the last time the unit stopped. The value“1” corresponds to the first day of the month.

Last Stop Year 08EAThe stop year location stores the last two digits of the year corresponding to the last time the unitstopped.

Liquid Line Refrigerant Temperature 048D-8ELiquid line refrigerant temperature is the temperature of liquid refrigerant leaving the condenser. Thedata represents a valid temperature only if the resultant value is between -40°F and 263°F. Theresolution of the value is 0.1°F.

Outdoor Air Temperature 047D-7EThe outdoor air temperature value is either from a local sensor or from a sensor on anotherMicrotech unit.

Refrigerant Detection Sensor 0874The value in refrigerant detection sensor location indicates whether the unit has a refrigerant leakdetection sensor connected to the unit. A zero indicates a sensor is not present; a one indicates asensor is present. Refrigerant leak detection limit is only valid when a sensor is present.

Refrigerant Leak Detection Limit 0494The value in the refrigerant leak detection location is the parts per million (PPM) value of refrigerantparticles detected by the refrigerant leak detection sensor. If a sensor is present, the valid data rangeis 0 to 100 which corresponds to 0 to 100 PPM.


21 Version 1.2

Unit Status 04CEUnit status is the current unit status of the chiller. The following is a list of possible states and theircorresponding number.

State Name ValueOff: All Systems 0Off: Panel Rocker Switch 1Off: Manual 2Off: Pumpdown Switch 3Off: Ambient Temperature Lockout 4Off: Remote Communications 5Off: Remote Switch 6Off: Time Schedule 7Off: Waiting for Flood 8Start Requested 9Evaporator Pump Off 10Evaporator Pump On - Waiting for Flow 11Evaporator Pump On - Recirculation 12Evaporator Pump On - Cycle Timer 13Evaporator Pump On - Waiting for Load 14Condenser Pump Off 15Condenser Pump On - Waiting for Flow 16Cool Staging 17Manual Cool Staging 18Cool Stage Up 19Cool Stage Down 20Shut Down/Pump Down 21Condenser Pump Off Shutdown 22Evaporator Pump Off Shutdown 23


Version 1.2 22

Read and Write Memory Locations.

Description Address Range (X) Units/Description

Clear Current Fault – Circuit 1 091A 0-1 0 = No Action1 = Clear Fault

Clear Current Fault – Circuit 2 091B 0-1 0 = No Action1 = Clear Fault

Chiller Operation Mode 044F 0, 1 0 = Enable1 = Disable

Chilled Water Temp Setpoint / MinimumChilled Water Temp Setpoint

0905 20-160 X / 2 = °F

Entering Evaporator Water Temp ResetSetpoint

090D 80-160 X / 2 = °F

Maximum Chilled Water Reset Setpoint 090C 20-160 X / 2 = °F

Maximum Reset @ OAT 09A8 150-165 X - 100 = °F

Network Reset 044E 0-255 X / 10 = °F

No Reset @ OAT 09A7 170-185 X - 100 = °F

Outdoor Air Temperature from BAS 0CC8 1-255 X - 100 = °F

Outdoor Air Temperature Method 087C 0-2 0 = Not Present1 = Local Sensor2 = Remote


23 Version 1.2

Read and Write Memory Definitions

Clear Current Fault – Circuit 1 091AClear Current Fault – Circuit 2 091BThe clear current fault location is used to clear the current active fault and re-initialize the unitcontroller. Writing a one to this location initiates this action. Once the fault has been cleared thecontroller will set this location back to zero.

Chiller Operation Mode 044FThe value in the chiller operation mode location is set to indicate the desired chiller operating mode.There are two possible values. Zero indicates "Enable". This does not necessarily turn the chiller on,this merely enables the chiller to operate if there is a need. A one indicates "Disable". Thecompressor and water pumps will turn off and all valves will close.

Chilled Water Temp Setpoint / Minimum Chilled Water Temp Setpoint 098CThe chilled water temperature setpoint is the temperature the leaving evaporator water will be cooledto if the unit is using this value for control. The data range of 20 to 160 corresponds to thetemperature range of 10ºF to 80ºF with 0.5ºF resolution. The setpoint should not be set below 40ºFfor standard temperature chiller units and may be set to 0°F for low temperature units.If using one of the reset options (OA, 4-20mA, Network, Return, or Ice), this memory locationbecomes the minimum chilled water temp setpoint. This location is used in conjunction with theother memory locations to provide a range for the reset. See page 26 for details on reset options.See: Chilled Water Temperature - Active Setpoint and Chiller Unit Temperature Type on page 3.Maximum Chilled Water Reset Setpoint below.

Entering Evaporator Water Temp Reset Setpoint 090DThe entering evaporator water temp reset setpoint is the temperature where the water entering theevaporator will have no reset. Maximum chilled water reset will occur at the Chilled Water TempSetpoint / Minimum Chilled Water Temp Setpoint (0905). See page 27 for detail on Return reset.

Maximum Chilled Water Reset Setpoint 090CThe maximum chilled water reset setpoint is the maximum reset of the chilled water temp setpoint.See page 26 for reset optionsSee: Chilled Water Temp Setppoint / Minimum Chilled Water Temp SetpointMaximum Reset @ OAT 09A8The maximum reset @ OAT location is the outdoor air temperature where the chilled water setpointwill have a maximum reset. See page 27 for details on OAT reset.

Network Reset 044EThe network reset location is the amount of reset to be added to the minimum chilled water tempsetpint when using the Network rest option. This location must be a multiple of 5. See page 26 forinformation on the Network reset.No Reset @ OAT 09A7The no reset @ OAT location is the outdoor air temperature where the chilled water setpoint willhave no reset. See page 27 for details on OAT reset.

Outdoor Air Temperature from BAS 0CC8The OaT from BAS is the outdoor air temperature as directed by the BAS. This location should notbe used if the outdoor air temperature is provided by a network controller (RMS or CSC). The OaTfrom BAS location is only valid if the outdoor air temperature method is set to “Remote”. Seeoutdoor air temperature method below.

Never write to thismemory location

without investigatingand correcting thecause of the fault.


Version 1.2 24

Outdoor Air Temperature Method 087CThe OaT method location indicates the method by which the chiller is receiving the outdoor airtemperature value. A zero represents “None” and indicates no OaT value is used. A one represents“Local” and indicates that the temperature is supplied by a sensor connected to the chiller. A tworepresents “Remote” and indicates that the temperature is being provided by another source. Thissource can be from either a MicroTech network controller (RMS or CSC) or the BAS.


25 Version 1.2

Chilled Water Rest Options

4-20mAThis chilled water rest option requires an external 4-20mA signal. A 0-4mA signal provides no resetwhile a 20mA signal provides a maximum reset. A linear relationship between the external 4-20mAsignal and the MinSpt abtnd MaxSpt is as follows:ActiveChWSpt = MinSpt + (mA-4)/(20-4)*MaxSptwhere,ActiveChWSpt = Chilled Water Temperature - Active Setpoint ($098C)

MinSpt = Minimum Chilled Water Temp Setpoint ($0905)mA = External Signal

MaxSpt = Maximum Chilled Water Reset Setpoint ($090C)

This chilled water reset option is only used on chillers designed to produce ice. This option will usethe Minimum Chilled Water Temp Setpoint ($0905) as the active setpoint when the chiller is in Icemode. The Maximum Chilled Water Reset Setpoint ($090C) is the active setpoint when the chiller isnot in Ice mode.

NetworkThis chilled water reset option is used when the Temperature Control Company wishes to have directcontrol over the chilled water reset. The chilled water temperature setpoint is reset as follows:ActiveChWSpt = MinSpt + (mA-4)/(20-4)*MaxSptwhere,ActiveChWSpt = Chilled Water Temperature - Active Setpoint ($098C)

MinSpt = Minimum Chilled Water Temp Setpoint ($0905)mA = External Signal

MaxSpt = Maximum Chilled Water Reset Setpoint ($090C

Note: Note: The Network Reset (044E) must be a multiple of 5.

OATThis chilled water reset option is used when the reset is to be controlled by the outdoor airtemperature. As the outdoor air temperature cools, the active chilled water temperature setpoint isincreased as follows:ActiveChWSpt = MinSpt + (OAT - MaxOATReset) * MaxSpt /(MinOATReset - MaxOATReset)where,

ActiveChWSpt = Chilled Water Temperature - Active Setpoint ($098C)MinSpt = Minimum Chilled Water Temp Setpoint ($0905)

OAT = Outdoor Air Temperature (047D-7E)MaxOATReset = Maximium Reset @ OAT ($09A7)

MaxSpt = Maximum Chilled Water Reset Setpoint ($090C)MinOATReset = Minimum Reset @ OAT ($09A8)


Version 1.2 26

ReturnThis chilled water reset option is used when the reset is to be controlled by the return watertemperature. As the return water cools, the active water temperature setpoint is increased as follows:ActiveChWSpt = (EntWTemp - MinSpt) * MinSpt / (EntWResetSpt - MinSpt)where,ActiveChWSpt = Chilled Water Temperature - Active Setpoint ($098C)

EntWTemp = Evaporator Water Temperature - Entering ($0477-0478)MinSpt = Minimum Chilled Water Temp Setpoint ($0905)

EntWResetSpt = Entering Evaporator Water Temp Reset Setpoint ($090D)MaxSpt = Maximum Chilled Water Reset Setpoint ($090C)


27 Version 1.2

Required Development Testing Tools

Developing and testing an Open Protocol interface for the screw chillers requires:1. (1) Model 250

(1) Model 120 (optional to test OPM configuration)(1) Power supply with power cord and adapter cables(1) RS-232 Communications Cable package(1) RS-485 Communication Cable package

2. Microsoft Windows-based McQuay Open Protocol Monitor and Simulator software for thescrew chiller available on McQuay-Online. If you do not have access to McQuay-Online, pleasecontact McQuay’s Controls and Network Systems Marketing Group for software and access.

Setup of Hardware for TestingOne setup that is particularly helpful for proving out an Open Protocol interface is to direct connectboth the BAS interface and the simulator monitor software simultaneously, as shown below. In thisarrangement, the Open Protocol interface to the TCC Comm device is operational on the controller'sPort B and the McQuay Monitor program is operational on a PC connected to the controller's Port A.The HEX switches on the Model 250 Controller will be Hi = F and Lo = F. In this configuration bothports are TTY (PC accessible) and Port A is always 1200 baud and Port B is 9600 Baud. Rememberto always turn power off and on after resetting addresses.


Version 1.2 28

Simulator Monitor Software Guide

OverviewA simulator Windows based monitor software is available for most of McQuay’s products offeringOpen Protocol. This version of the screw chiller does not as of this document date have asimulator monitor software. Once one becomes available, it will be posted on McQuay Online. Thesoftware is intended to be a live monitoring version of this document. You will be able to testacquiring data from your interface to a simulator controller. We have disabled all of the sensor tasksfrom our real controller code to furnish a simulator control code, which is the .cod file(s) in yourdirectory where you have installed the monitor software. This code in most cases will not simulatechanging of control modes. If a detailed sequence of operation is required to further understand theoperation of any unit, please consult the appropriate Operation Manual (OM). These documents areavailable upon request and are currently NOT on McQuay-Online.

Logging on to the softwareIf you have an old copy of the monitor software that has not been updated yet and a password isrequired and you can not get into the software, please contact McQuay International Controls andNetwork Systems Marketing group on McQuay On-line. Simulator Monitor software released after January 1, 1997 will have a username: MCQUAYpassword: PARTNER.

Communications InitializationAfter logging in you will be asked to initiate communications

If you are connecting to a simulator controller you will want to select YES. If you are successful atconnecting you will be at the main screen. If you are unsuccessful you will see the following:


29 Version 1.2

If you see this screen you may have a communications setup problem. You may select the ChangeSetup function to change communications parameters. You will come to a screen that looks like:


Version 1.2 30

The problem is most likely you are using the wrong comm port on your PC. Check to make sure youare using either Comm 1 or Comm 2. The password for the controller will most likely be the defaultshown (FFFFFFFF). If for some reason your simulator has a different password, you may enter anew password here to try and establish communications to the controller. Note that this passworddoes not change the controller password, it merely tries to match one of the four level passwords thatexist in the controller. The connection type needs to be DIRECT, however the BAUD RATE doesnot need to match the baud rate that the controller port is set up for. When direct connecting to acontroller the monitor software will test all possible connection speeds from 300 to 9600 Baud until aconnection is made or all baud rates have been attempted. Once you have adjusted the aboveparameters, you may attempt to connect to the controller once again by pressing the Init Commbutton.

Downloading Simulation codeOnce you have connected to the controller you may need to download simulator application code.From the Main Menu bar select the Support option. Under the menu items for support you will findDownload. Select Download and you should see the following screen:

The controller address should be 00.ff in the case of a single unit connection. 00.ff is a specialaddress which tells the software to connect to the direct connected controller regardless of thecontroller’s address setting. Alternately, you may enter the address of the controller, however whentrying to connect in this manner, the address must match. The Save Data, Download Program,Restore Data option should be chosen for every download. The program file will be the simulatorcode you wish to download to the controller. The data file is a temporary file in which will be storedcontroller data during the download process. This file may be deleted off of your hard drive aftersuccessful download. You must specify a data file name but the name of the file is arbitrary. Thesave options you should have checked are Port Configuration and Passwords.You should see the download progress dialog box after initiating the download:


31 Version 1.2

Monitoring a simulator controllerOnce the code is properly downloaded into the simulator controller, you may begin to monitormemory locations in the Windows Simulator Monitor Software. From the Main Menu, chooseScreen, and select Monitor Unit. Double-click the appropriate screen to start seeing simulator data. Ifyou do not start seeing data, you may not have established a connection to the controller.

Support Menu - Read/Write screens You may want to use the read/write screen in conjunction with the monitor screens to double checkthe raw data values coming back from the controller. The following screen is an example of how touse the read/write screen for comparison. The Monitor Screen option has been selected and theread/write option has also been selected (from the main menu, support option).


Version 1.2 32

The above memory location for Chilled Water Temperature displays 44 degrees F. In the read/writescreen you can see the decimal value of memory location $0905 which is 88. The conversion in thiscase is value/2 to get degrees F.


33 Version 1.2

Disabling the Simulator Control CodeThe simulator control code is a compiled version of the real control code with all of the sensorsdisabled. You may find that you want to test a memory location, but the simulator code doesn’t allowthe change or it simply rewrites the previous value to that memory location. The following techniquemay be used to disable all of the tasks in the simulator code so that you may alter any memorylocation and the value will not be altered by the control code. Below is a read/write screen withmemory locations 0300-032F shown. Note that the monitor function is chosen. When you monitorthis screen, the values will change rapidly. If $FF or 255 decimal is written to each of these memorylocations, the task timer will stop. If you want the task timers to start again, write a 1 to each memorylocation. If you select the 0300 to change, there is an option to change a single location or globalchange so you do not have to change each one individually. You may get an error writing to trailingmemory locations, this is OK since not all of the trailing memory locations are task timers.


Version 1.2 34

Further Information on Windows Monitor SoftwareThis document should get you started using Windows Monitor. You should not have to use any ofthe other functions of Windows Monitor in order to test your interface. If further information onWindows Monitor is desired, please refer to McQuay International MicroTech Monitor 1.0 forWindows User’s Manual.


35 Version 1.2

Glossary of Terms

BASBuilding Automation System

KPAKilopascals

OATOutdoor Air Temperature

OPMOpen Protocol Master

PFSMcQuay screw chiller, water-cooled

PSIPounds Per Square Inch

13600 Industrial Park Boulevard, P.O. Box 1551, Minneapolis, MN 55440 USA (763) 553-5330 (www.mcquay.com)

Revision HistoryVersion 1.2Version 1.1Version 1.0

OverviewCompatible Unit Control Software for Open ProtocolNetwork ConfigurationCommunications to a Single ChillerCommunications to Two or More Chillers

Supplemental LiteratureConversions and ConventionsConverting 2 Byte VariablesNote on TemperaturesNote on Pressures

OPM - Open Protocol Master PanelRead Only Memory LocationsRead Only Memory DefinitionsRead and Write Memory Locations.Read and Write Memory DefinitionsChilled Water Rest Options4-20mANetworkOATReturn

Required Development Testing ToolsSetup of Hardware for Testing

Simulator Monitor Software GuideOverviewLogging on to the softwareCommunications InitializationDownloading Simulation codeMonitoring a simulator controllerSupport Menu - Read/Write screensDisabling the Simulator Control CodeFurther Information on Windows Monitor Software

Glossary of Terms

microtech® c vintage water-cooled™ screw chiller...opm - open protocol master panel there is only...

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