Read Series 200 Centrifugal Chiller BACnet Variables text version

Open Protocol Data Information Packet

Version 2.2

Group: Controls Date: August 2002

MicroTech® Series 200 Centrifugal Chiller

Data Communications Packet for Open ProtocolTM

© 2002 McQuay International

Revision History

8/02 Version 2.2 3/99 Document Only Change: Added Fault ­ "Current Active 46, Master/Slave Comm Loss" Changed the Communications Signal $047D. A value of 255 must be written to this location every minute to establish communications with open protocol! Added High Suction Superheat (value 45 for current fault) Changed definition of the communications status $040C point Version 2.1 1/98 Added read only point communications status $040C, to monitor communication status. This is used in conjunction with communications signal $047D. Added verbiage. The control mode setpoint (read/write $0477) must be written to both the master and slave units when 2 Series 200 centrifugal chillers are in the lead/lag configuration. Version 2.0 Removed I/O hardware list. This information is kept up to date in the product Installation & Maintenance manual. Added Communication Error (value 44 for current fault) Added option for network enable (read/write) for chiller operation mode (value=1) Version 1.1 4/96 This revision is a formatting change. I/O configuration list added. Memory locations for lead/lag operation added. Version 1.0 6/95 Initial release of the document.

Proprietary This Document may not be copied or reproduced in any way without the express written consent of McQuay International. Notice Copyright © 2002 McQuay International, Minneapolis MN All rights reserved throughout the world. McQuay International reserves the right to change any information contained herein without prior notice. No guarantees are given as to the accuracy of information provided.

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Contents

Revision History ................................................................................................................................... 2 Contents ................................................................................................................................................ 3 Overview.................................................................................................................................4 Introduction........................................................................................................................................... 4 Network Configuration ......................................................................................................................... 4 Compatible Unit Control Software ....................................................................................................... 4 Supplemental Literature ........................................................................................................................ 5 Conversions and Conventions............................................................................................................... 5 Glossary of Terms ................................................................................................................................. 6 Read Only Memory Location Tables .................................................................................................... 6 Read Only Memory Definitions.......................................................................................................... 10 Read and Write Memory Location Table............................................................................................ 18 Read and Write Memory Definitions .................................................................................................. 19 Lead/Lag Load Balance Operation ....................................................................................21 Overview............................................................................................................................................. 21 Read/Write Memory Locations........................................................................................................... 21 Read Only Memory Locations ............................................................................................................ 22 Series 200 Centrifugal Chiller Simulator Package ...........................................................23 Purpose................................................................................................................................................ 23 Development Tools ............................................................................................................................. 23 Monitor Installation............................................................................................................................. 23 Hardware Configuration ..................................................................................................................... 23 Testing................................................................................................................................................. 24 Simulator Monitor Software Guide ....................................................................................24 Logging on to the software ................................................................................................................. 24 Communications Initialization ............................................................................................................ 25 Downloading Simulation code............................................................................................................ 26 Monitoring a simulator controller ....................................................................................................... 28 Read/Write screens ............................................................................................................................. 28 Further Information on Windows Monitor Software .......................................................................... 29

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Series 200 Centrifugal Chiller

Overview

Introduction

McQuay International's Open ProtocolTM for MicroTech® Series-200 centrifugal chillers allows independent building automation system companies to integrate McQuay® centrifugal chiller equipment into their building control systems. Automation integrators can communicate with a single chiller or a networked group of chillers with simple RS-485 communications. Using Open Protocol, the integrator has access to relevant control information and may alter the equipment operating state by adjusting specific controller memory locations provided by McQuay. This manual completely defines accessible memory locations and provides instructions on the use of McQuay's Open Protocol Hardware Development Kit. With the manual and development kit, a fully functional interface to McQuay Series-200 centrifugal chillers can easily be developed. The purpose of a chiller is to cool the water that passes through it. When the unit is operating, the MicroTech controller monitors the leaving chilled water temperature and compares it to the chilled water temperature setpoint. If the water temperature is not the desired value, the controller will adjust unit operation to achieve the setpoint temperature. McQuay manufactures two types of centrifugal chillers: single compressor and dual compressor units. Single compressor units have one MicroTech control panel and dual units have two. In a dual configuration, each panel controls one of the two compressor circuits in the unit. Sequencing control and load balancing logic for dual units can be provided by either control panel. The panel which controls these functions is selected by the unit operator.

Network Configuration

The Network interface on the OPM is a daisy chained, multi-drop, 9600 baud, RS-485 proprietary McQuay network interface. The chiller controller is factory mounted and provides pre-programmed, pre-engineered and pretested stand-alone control. There is one controller for each chiller. A dual chiller is considered to be 2 chillers and thus has two controllers. When the McQuay network has been commissioned (by a McQuay representative), the BAS vendor can connect to the McQuay interface controller. Chillers continue to operate even when communications are lost; the network must be intact for the BAS to control the chillers.

Compatible Unit Control Software

You must know IDENT of the software in the chiller to know which variables are applicable. The software IDENT includes the version number (the last two numbers) of the software and its revision level (the last letter). Your McQuay representative can give you this information, or if the unit is already installed, the IDENT information may be read directly from the keypad display. Note: Software revisions do not affect variables; however, software versions typically indicate a major change in the software. Usually, software changes do not affect variables either.

This edition of this Open Protocol information packet documents revision I of the standard software and all subsequent revisions of version 04 until otherwise indicated. If you encounter a later version of code, please refer to McQuay Online for an update to this document.

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This Open Protocol document specifically addresses chiller applications utilizing MicroTech Series-200 control software. McQuay has provided a means of verifying the use of Series-200 software by embedding an eight character software identification string in the unit controller's read only memory. The string is written as ASCII characters in a hex number format and is located in memory locations 0A08-0A0F. The table below defines valid identification strings. Address 0A08, 0A09, 0A0A 0A0B Characters Description Defines code as Series-200 chiller. (Always the 1st three characters.) Refrigerant type.

C, F, G

1 = R12 2 = R22 3 = R134a 4 = R114 5 = R500 E = English S = SI/Metric D = Kana (Japanese) 01-99 A-Z

0A0C

Display - Units of measure / language type.

0A0D, 0A0E 0A0F

Software version number. Software revision number.

The software version number typically indicates a significant change in the control code. This document is valid for all version of software code up to the latest version which is version 4. The revision character may change frequently and indicates minor changes to the control code and never effects open protocol. An upgrade in version number generally does not effect open protocol either. Please connect to McQuay Online if a later version of code is encountered in the field to see if the information contained in this document is still valid.

Supplemental Literature

Use the following manuals with this information packet. Operation manuals contain a detailed sequence of operation. Installation and Maintenance manuals contain unit wiring details.

OM-125 IM 615 Series 200 MicroTech Control Panel Operation Manual Series 200 MicroTech Control Panel Installation Manual

Conversions and Conventions

Note on Temperatures

All temperatures are stated in degrees Fahrenheit, to get degrees Celsius, you must use the standard formula for temperature conversion:

C=

5 × ( F - 32) 9

Note on Pressures

All pressures are stated in PSI, to get KPA, you must use the following standard conversion:

KPA = 6.89 × PSI

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Series 200 Centrifugal Chiller

Glossary of Terms

BAS KPA OAT PSI RLA Building Automation System Kilopascals Outdoor Air Temperature Pounds Per Square Inch Rated Load Amps

Read Only Memory Location Tables

Description Chilled Water Temperature- Active Setpoint Chiller Unit Temperature Type 0 = Standard 1 = Low Temperature Communication Status 0 = Communications time-out 1 = Active communications Compressor Lift Pressure Compressor Motor Current Compressor Motor Current Percent Compressor Number of Starts Compressor Operating Hours Compressor Suction Temperature Address 0905 Range (X) 0-160 Conversion X/2 Units °F

084B

0, 1

040C

0,1

046A-046B 044C-044D 044A 085F-0860 0851-0852 043A-043B

0-65,535 0-65,535 0-125 0-49,999 0-49,999 600-3,630 63,985 = Short 61,425 = Open 0-2,630 0-2,630 0-2,630 0, 1

X/10

PSIG Amps % Compressor starts hrs

(X - 1000) / 10

°F

Compressor Superheat Discharge Compressor Superheat Suction Condenser Approach Temperature Condenser Heat Recovery Unit Present 0 = Not Present 1 = Present Condenser Heat Recovery Temperature - Delta

046E-046F 046C-046D 0484-0485 083F

X / 10 X / 10 X / 10

ºF ºF °F

048A-048B

0-2,630

X / 10

°F

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Description Condenser Heat Recovery Water Temp. - Entering

Address 0454-0455

Range (X) 600-3,630 63,985 = Short 61,425 = Open 58,865 = N/A 600-3,630 63,985 = Short 61,425 = Open 58,865 = N/A 0-7 0-49,999 0-49,999 0-4,500 63,985 = Short 61,425 = Open 600-3,630 63,985 = Short 61,425 = Open 0-2,630 0-65,535 0, 1 0, 1

Conversion (X - 1000) / 10

Units °F

Condenser Heat Recovery Water Temp. - Leaving

0456-0457

(X - 1000) / 10

°F

Condenser Pump Status Condenser Pump # 1 Operating Hours Condenser Pump # 2 Operating Hours Condenser Refrigerant Pressure

0425 085A-085B 085D-085E 0440-0441

See Below hrs hrs X / 10 PSIG

Condenser Refrigerant Temperature

0466-0467

(X - 1000) / 10

°F

Condenser Subcooling Temperature Condenser Water Flow Rate Condenser Water Flow Status Condenser Water Rate Sensor 0 = Not Present 1 = Present Condenser Water Temperature - Delta Condenser Water Temperature - Entering

0480-0481 0452-0453 045F 083D

X / 10

ºF GPM 0 = No Flow 1 = Flow

0488-0489 0436-0437

0-2,630 600-3,630 63,985 = Short 61,425 = Open 600-3,630 63,985 = Short 61,425 = Open

X / 10 (X - 1000) / 10

°F °F

Condenser Water Temperature - Leaving

0434-0435

(X - 1000) / 10

°F

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Series 200 Centrifugal Chiller

Description Cooling Tower Control 0 = External 1 = Chiller Cooling Tower Stage Cooling Tower Valve Position Discharge Refrigerant Temperature

Address 0926

Range (X) 0, 1

Conversion

Units

049A 049B 043E-043F

0-6 0-100 600-3,630 63,985 = Short 61,425 = Open 0-2,630 0-7 0-49,999 0-49,999 0-1,500 63,985 = Short 61,425 = Open 600-3,630 63,985 = Short 61,425 = Open 0-65,535 0, 1 X / 10 (X - 1000) / 10

stages % °F

Evaporator Approach Temperature Evaporator Pump Status Evaporator Pump #1 Operating Hours Evaporator Pump #2 Operating Hours Evaporator Refrigerant Pressure

0482-0483 0423 0854-0855 0857-0858 0438-0439

X / 10

°F See Below hrs hrs PSIG

Evaporator Refrigerant Temperature

0464-65

(X - 1000) / 10

°F

Evaporator Water Flow Rate Evaporator Water Flow Status 0 = No Flow 1 = Flow Evaporator Water Rate Sensor 0 = Not Present 1 = Present Evaporator Water Temperature - Delta Evaporator Water Temperature - Entering

0450-0451 045E

GPM

083C

0, 1

0486-0487 0432-0433

0-2,630 600-3,630 63,985 = Short 61,425 = Open 600-3,630 63,985 = Short 61,425 = Open

X / 10 (X - 1000) / 10

°F °F

Evaporator Water Temperature - Leaving

0430-0431

(X - 1000) / 10

°F

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Description Fault - Current Active Last Start Hour Last Start Minute Last Start Month Last Start Date Last Start Year Last Stop Hour Last Stop Minute Last Stop Month Last Stop Date Last Stop Year Liquid Line Refrigerant Temperature

Address 1C00 0861 0862 0863 0864 0865 0866 0867 0868 0869 086A 043C-043D

Range (X) 0-46 0-23 0-59 1-12 1-31 0-99 0-23 0-59 1-12 1-31 0-99 600-3,630 63,985 = Short 61,425 = Open 0-4,500 63,985 = Short 61,425 = Open 0-4,500 0-1,500 63,985 = Short 61,425 = Open 600-3,630 63,985 = Short 61,425 = Open 600-3,630 63,985 = Short 61,425 = Open 60-252 253=N/A 255= Bad Sen 0, 1

Conversion

Units See Below hour minute month day year hour minute month day year

(X - 1000) / 10

°F

Oil Pressure - Feed

0446-0447

X / 10

PSIG

Oil Pressure - Net Oil Pressure - Vent

0468-0469 04AC04AD

X / 10 X / 10

PSIG PSIG

Oil Temperature - Feed

0442-0443

(X - 1000) / 10

°F

Oil Temperature - Sump

0444-0445

(X - 1000) / 10

°F

Outdoor Air Temperature Network

0474

X-100

°F

Refrigerant Detection Sensor 0 = Not Present 1 = Present Refrigerant Leak Detection Limit Unit Status

083E

044B 0420

0-100 0-27

PPM See Below

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Series 200 Centrifugal Chiller

Read Only Memory Definitions

A definition name followed by an asterisk (*) indicates that the data point is not always supported. Chilled Water Temperature - Active Setpoint 0905 The chilled water temperature location contains the active chilled water setpoint the unit is using for temperature control. The active setpoint may be set by several control scenarios which are dependent upon chiller configuration parameters. A data range of 0 to 160 corresponds to the temperature range of 0ºF to 80ºF with 0.5ºF resolution. Chiller Unit Temperature Type 084B Unit temperature type indicates whether the unit is a low or standard discharge temperature unit. A value of zero indicates a standard chiller unit; a one indicates a low temperature unit. Communication Status 040C This point monitors the status of network communications. If the read/write point communications signal expires, the value in the location will become zero. A one will be read if the communications signal is active. Compressor Lift Pressure 046A-6B Lift pressure is the pressure rise of the refrigerant gas as it passes through the compressor. Lift pressure is calculated by subtracting evaporator refrigerant pressure from the condenser refrigerant pressure. It is a two byte value, where location 046A contains the high byte and 046B contains the low byte. The BAS integrator should assume this value will always be valid. The resolution of the value is 0.1 PSIG. Compressor Motor Current 044C - 4D Motor current holds the number of electrical Amps. being drawn by the compressor motor measured with a 1.0 A resolution. The data is a two byte value, where location 044C contains the high byte and 044D contains the low byte. The range for this data is dependent on the size of the motor. The BAS integrator should assume this value will always be valid. Compressor Motor Current Percent 044A Motor current percent stores the number of electrical Amps. the compressor motor is drawing as a percentage of its Rated Load Amps (RLA). The data represents a valid percentage only if the resultant value is between 0-125% of RLA. The resolution of the value is 1.0%. Compressor Number of Starts 085F-60 Number of starts stores the number of compressor motor starts that have occurred. Compressor starts is a two byte value, where location 085F contains the high byte and 0860 contains the low byte. These locations contain valid data only if the value is between 0 and 49,999. The value will roll over to 0 once the 50,000 start has occurred. Compressor Operating Hours 0851-52 Operating hours stores the number of hours the compressor has run. Operating hours is a two byte value, where location 0851 contains the high byte and 0852 contains the low byte. The data is valid when in the range of 0 and 49,999. The value will roll over to zero (0) once the 49,999 hour has been completed. Compressor Suction Temperature 043A-3B Suction temperature is the temperature of the refrigerant gas entering the compressor. Suction temperature is a two byte value, where location 043A contains the high byte and 043B contains the low byte. The data represents a valid temperature only if the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F.

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Compressor Superheat - Discharge 046E-6F Discharge superheat is the temperature difference between the refrigerant gas leaving the compressor and the refrigerant phase change temperature point. It is derived by subtracting a calculated condenser refrigerant phase change temperature from discharge refrigerant temperature. Superheat temperature is a two byte value, where location 046E contains the high byte and 046F contains the low byte. The data represents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F. Compressor Superheat - Suction 046C-6D Suction superheat is the temperature difference between the refrigerant gas entering the compressor and the refrigerant phase change temperature point. It is derived by subtracting a calculated evaporator refrigerant phase change temperature from the compressor suction temperature. Superheat temperature is a two byte value, where location 046C contains the high byte and 046D contains the low byte. The data represents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F. Condenser Approach Temperature 0484-85 The approach temperature is the difference in temperature between the condenser refrigerant and the condenser leaving water. It is calculated by subtracting leaving condenser water temperature from condenser refrigerant temperature. The temperature is a two byte value, where location 0484 contains the high byte and 0485 contains the low byte. The data represents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F. Condenser Heat Recovery Unit Present 083F The heat recovery present location indicates whether the chiller has a condenser heat recovery unit. A zero indicates a heat recovery unit is not present; a one indicates a unit is present. Heat recovery temperature data points are valid only if a heat recovery unit is present. Condenser Heat Recovery Temperature - Delta* 048A-8B The heat recovery present location indicates whether the chiller has a condenser heat recovery unit. A zero indicates a heat recovery unit is not present; a one indicates a unit is present. Heat recovery temperature data points are valid only if a heat recovery unit is present. Condenser Heat Recovery Water Temperature - Entering* 0454-55 The entering recovery temperature is the temperature of the water flowing into the condenser heat recovery unit. It is a two byte value, where location 0454 contains the high byte and 0455 contains the low byte. The data represents a valid temperature only if a heat recovery unit is present and the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F. Condenser Heat Recovery Water Temperature - Leaving* 0456-57 The leaving recovery temperature is the temperature of the water flowing out of the condenser heat recovery unit. It is a two byte value, where location 0456 contains the high byte and 0457 contains the low byte value. The data represents a valid temperature only if a heat recovery unit is present and the resultant temperature is between -40°F and 263°F. The resolution of the value is 0.1°F. Condenser Pump Status Pump status stores the operating status of the condenser water pumps. 0425

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Series 200 Centrifugal Chiller

Status Condenser Pumps Off Starting Condenser Pump #1 Starting Condenser Pump #2 Condenser Pump #1 On Condenser Pump #2 On Condenser Pump #1 Fail; Starting #2 Condenser Pump #2 Fail; Starting #1 Condenser Pumps #1 & 2 Failed

Value 0 1 2 3 4 5 6 7

Condenser Pump #1 Operating Hours 085A-5B Pump #1 operating hours stores the number of hours condenser pump #1 has run. Operating hours is a two byte value, where location 085A contains the high byte and 085B contains the low byte. These locations contain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999 hour has been completed. Condenser Pump #2 Operating Hours 085D-5E Pump #2 operating hours stores the number of hours condenser pump #2 has run. Operating hours is a two byte value, where location 085D contains the high byte and 085E contains the low byte. These locations contain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999 hour has been completed. Condenser Refrigerant Pressure 0440-41 Refrigerant pressure is the pressure of the refrigerant gas in the condenser shell. The pressure is a two byte value, where location 0440 contains the high byte and 0441 contains the low byte. The data represents a valid pressure only if the resultant value is between 0 and 450 PSIG. The resolution of the value is 0.1 PSIG. Condenser Refrigerant Temperature 0466-67 Refrigerant temperature is the temperature of refrigerant gas in the condenser shell. The temperature is a two byte value, where location 0466 contains the high byte and 0467 contains the low byte. The data represents a valid temperature only if the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F. Condenser Subcooling Temperature 0480-81 Subcooling is the temperature difference between the liquid refrigerant leaving the condenser and the refrigerant phase change temperature point. It is derived by subtracting the liquid line refrigerant temperature from a calculated condenser refrigerant phase change temperature. The data represents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F. Condenser Water Flow Rate* 0452-53 Water flow rate stores the rate of water flowing through the condenser tubes. Water flow is a two byte value, where location 0452 contains the high byte and 0453 contains the low byte. The resolution for this value is 1 GPM and the range is dependent on the condenser flow sensor. If a condenser flow rate sensor is present the data will always be valid. Condenser Water Flow Status 045F The value in the condenser water flow status location indicates the position of the condenser water flow switch. A zero indicates no water flow through the condenser; a one indicates water movement. Condenser Water Rate Sensor 083D The value in the condenser water rate sensor location indicates whether a condenser flow rate sensor is 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.

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Condenser Water Temperature - Delta 0488-89 The delta temperature is the difference between the entering and leaving condenser water temperatures. The value is calculated by subtracting entering condenser water temperature from leaving condenser water temperature. The temperature is a two byte value, where location 0488 contains the high byte and 0489 contains the low byte. The data represents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F. Condenser Water Temperature - Entering 0436-37 Entering water temperature is the temperature of the water entering the condenser. It is a two byte value, where location 0436 contains the high byte and 0437 contains the low byte value. The data represents a valid temperature only if the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F. Condenser Water Temperature - Leaving 0434-35 Leaving water temperature is the temperature of the water leaving the condenser. The water temperature is measured with a 0.1°F resolution. It is a two byte value, where location 0434 contains the high byte and 0435 contains the low byte. The data is valid only if the resultant temperature is between -40°F and 263°F. Cooling Tower Control 0926 The value in the cooling tower control location indicates whether cooling tower functions are being controlled by the chiller unit or an external control system. A zero indicates that an external system is being used; a one indicates that the chiller is providing control. Cooling tower data points are only valid when the chiller is in control. Cooling Tower Stage* 049A The value in the cooling tower stage location indicates the number of cooling tower stages that are energized. The data is valid only if tower control is provided by the chiller. The valid range is 0 to 6. Cooling Tower Valve Position* 049B The valve position location stores the position of the cooling tower valve. The position is measured as a percent of full open and has a 1% resolution. The data is valid only if tower control is provided by the chiller. The valid range is 0-100%. Discharge Refrigerant Temperature 043E-3F Discharge refrigerant temperature is the temperature of the compressor refrigerant gas as it leaves the compressor. The refrigerant temperature is a two byte value, where location 043E contains the high byte and 043F contains the low byte. The data represents a valid temperature only if the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F. Evaporator Approach Temperature 0482-83 The approach temperature is the difference in temperature between the evaporator refrigerant and the evaporator leaving water. It is calculated by subtracting evaporator refrigerant temperature from leaving evaporator water temperature. The temperature is a two byte value, where location 0482 contains the high byte and 0483 contains the low byte value. The data represents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F. Evaporator Pump Status Pump status stores the operating status of the evaporator water pumps. Status Evaporator Pumps Off Starting Evaporator Pump #1 Starting Evaporator Pump #2 Evaporator Pump #1 On Evaporator Pump #2 On Value 0 1 2 3 4 0423

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Series 200 Centrifugal Chiller

Status Evaporator Pump #1 Fail; Starting #2 Evaporator Pump #2 Fail; Starting #1 Evaporator Pumps #1 & 2 Failed

Value 5 6 7

Evaporator Pump #1 Operating Hours 0854-55 Pump #1 operating hours stores the number of hours evaporator pump #1 has run. Operating hours is a two byte value, where location 0854 contains the high byte and 0855 contains the low byte. These locations contain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999 hour has been completed. Evaporator Pump #2 Operating Hours 0857-58 Pump #2 operating hours stores the number of hours evaporator pump #2 has run. Operating hours is a two byte value, where location 0857 contains the high byte and 0858 contains the low byte. These locations contain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the 49,999 hour has been completed. Evaporator Refrigerant Pressure 0438-39 Refrigerant pressure is the pressure of the refrigerant gas in the evaporator shell. The pressure is a two byte value, where location 0438 contains the high byte and 0439 contains the low byte value. The data represents a valid pressure only if the resultant value is between 0 and 150 PSIG. The resolution of the value is 0.1 PSIG. Evaporator Refrigerant Temperature 0464-65 Refrigerant temperature is the temperature of refrigerant gas in the evaporator shell. The temperature is a two byte value, where location 0464 contains the high byte and 0465 contains the low byte. The data represents a valid temperature only if the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F. Evaporator Water Flow Rate* 0450-51 Water flow rate stores the rate of water flowing through the evaporator tubes. Water flow is a two byte value, where location 0450 contains the high byte and 0451 contains the low byte. The resolution for this value is 1 GPM and the range is dependent on the evaporator flow sensor. If an evaporator flow rate sensor is present the data will always be valid. Evaporator Water Flow Status 045E The value in the evaporator water flow status location indicates the position of the evaporator water flow switch. A zero indicates no water flow through the evaporator; a one indicates water movement. Evaporator Water Rate Sensor 083D The value in the evaporator water rate sensor location indicates whether an evaporator flow rate sensor is connected to the unit. A zero indicates a sensor is not present; a one indicates a sensor is present. Evaporator water flow rate is only valid when this sensor is present. Evaporator Water Temperature - Delta 0486-87 Water temperature delta is the difference between the entering and leaving evaporator water temperatures. The value is calculated by subtracting evaporator leaving water temperature from entering evaporator water temperature. The temperature is a two byte value, where location 0486 contains the high byte and 0487 contains the low byte. The data represents a valid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F. Evaporator Water Temperature - Entering 0432-33 Entering water temperature is the temperature of the water entering the evaporator. It is a two byte value, where location 0432 contains the high byte and 0433 contains the low byte. The data represents a valid temperature only if the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F.

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Evaporator Water Temperature - Leaving 0430-31 Leaving water temperature is the temperature of the water leaving the evaporator. The water temperature is measured with a 0.1°F resolution. It is a two byte value, where location 0430 contains the high byte and 0431 contains the low byte. These locations contain valid data only if the resultant temperature is between -40°F and 263°F. Fault - Current Active 1C00 The fault location holds the current unit fault. If multiple faults should occur, the most serious fault will be stored in this location. Fault Condition No Fault Liquid Line Sensor Failure Entering Evaporator Water Sensor Failure: Warning Leaving Condenser Water Sensor Failure Low Discharge Superheat High Discharge Superheat Entering Evaporator Water Sensor Failure: Problem Outside Air Temperature Sensor Low Evaporator Pressure - No Load Low Evaporator Pressure - Unload High Discharge Temperature Load Condenser Freeze Protection Evaporator Freeze Protection Evaporator Pump #1 Failure Evaporator Pump #2 Failure Condenser Pump #1 Failure Condenser Pump #2 Failure Compressor Vanes Open at Startup Low Evaporator Pressure Low Oil Pressure Delta Low Oil Feed Temperature High Oil Feed Temperature Low Compressor Motor Current High Discharge Temperature High Condenser Pressure Mechanical High Condenser Pressure High Compressor Motor Temperature Surge-High Suction Superheat Compressor Motor No Evaporator Water Flow No Condenser Water Flow High Compressor Motor Current Compressor Motor Starter Fault Value 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

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Series 200 Centrifugal Chiller

Fault Condition Leaving Evaporator Water Sensor Failure Evaporator Pressure Sensor Failure Entering Condenser Water Sensor Failure Suction Temperature Sensor Failure Discharge Temperature Sensor Failure Condenser Pressure Sensor Failure Oil Feed Pressure Sensor Failure Oil Feed Temperature Sensor Failure Oil Sump Temperature Sensor Failure Oil Sump Pressure Sensor Failure Voltage Ratio Sensor Failure Communications Error High Suction Superheat Master/Slave Comm Loss

Value 33 34 35 36 37 38 39 40 41 42 43 44 45 46

Last Start Hour 0861 The start hour location stores the hour value corresponding to the last time the unit started in military time. Last Start Minute 0862 The start minute location stores the minute value corresponding to the last time the unit started. Last Start Month 0863 The start month location stores the month value corresponding to the last time the unit started. The value 1 corresponds to the month of January. Last Start Date 0864 The start date location stores the date value corresponding to the last time the unit started. The value 1 corresponds to the first day of the month. Last Start Year 0865 The start year location stores the last two digits of the year corresponding to the last time the unit started. Last Stop Hour 0866 The stop hour location stores the hour value corresponding to the last time the unit stopped in military time. Last Stop Minute 0867 The stop minute location stores the minute value corresponding to the last time the unit stopped. Last Stop Month 0868 The stop month location stores the month value corresponding to the last time the unit stopped. The value "1" corresponds to the month of January. Last Stop Date 0869 The 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 086A The stop year location stores the last two digits of the year corresponding to the last time the unit stopped.

Series 200 Centrifugal Chiller

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Liquid Line Refrigerant Temperature 043C-3D Liquid line refrigerant temperature is the temperature of liquid refrigerant leaving the condenser. The refrigerant temperature is a two byte value, where location 043C contains the high byte and 043D contains the low byte. The data represents a valid temperature only if the resultant value is between -40°F and 263°F. The resolution of the value is 0.1°F. Oil Pressure - Feed 0446 - 47 Feed pressure is the pressure at which refrigerant oil is being injected into the compressor. Oil pressure is a two byte value, where location 0446 contains the high byte and 0447 contains the low byte. The data represents a valid pressure only if the resultant value is between 0 and 450 PSIG. The resolution of the value is 0.1 PSIG. Oil Pressure - Net 0468-69 Net pressure is the difference between vent oil pressure and feed oil pressure. Oil pressure is a two byte value, where location 0468 contains the high byte and 0469 contains the low byte. These locations contain valid data only if the resultant temperature is between 0 and 450 psi. The resolution of the value is 0.1 PSIG. Oil Pressure - Vent 04AC-AD Vent pressure is the pressure of refrigerant oil in the oil vent return line. The pressure is a two byte value, where location 04AC contains the high byte and 04AD contains the low byte. The data represents a valid pressure only if the resultant value is between 0 and 150 PSIG. The resolution of the value is 0.1 psi. Oil Temperature - Feed 0442 - 43 Feed temperature is the temperature of the refrigerant oil being injected into the compressor. The oil temperature is a two byte value, where location 0442 contains the high byte and 0443 contains the low byte. These locations contain valid data only if the resultant temperature is between -40°F and 263°F. It is measured with a 0.1°F resolution. Oil Temperature - Sump 0444 - 0445 Sump temperature is the temperature of the refrigerant oil that is collecting in the oil sump. The oil temperature is a two byte value, where location 0444 contains the high byte and 0445 contains the low byte. These locations contain valid data only if the resultant temperature is between -40°F and 263°F. It is measured with a 0.1°F resolution. Outdoor Air Temperature Method 083B The OaT method location indicates the method by which the chiller is receiving the outdoor air temperature 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 two represents "Network" and indicates that the temperature is being provided by the BAS network. Outdoor Air Temperature - Network* 0474 The network outdoor air temperature is an 8-bit converted value of the chiller outdoor air temperature. It may be used by the BAS network for control situations that require a single byte outdoor air temperature. The data in this location is valid only if OaT method is set to "Local." The valid range of this value is -40°F to 152°F with a 1.0°F resolution. Refrigerant Leak Detection Limit* 044B The value in the refrigerant leak detection location is the parts per million (PPM) value of refrigerant particles detected by the refrigerant leak detection sensor. If a sensor is present, the valid data range is 0 to 100 which corresponds to 0 to 100 PPM. Refrigerant Detection Sensor 083E The value in refrigerant detection sensor location indicates whether the unit has a refrigerant leak detection sensor connected to the unit. A zero indicates a sensor is not present; a one indicates a sensor is present. Refrigerant leak detection limit is only valid when a sensor is present. Unit Status 0420 Unit status is the current unit status of the chiller. The following is a list of possible states and their corresponding number.

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Series 200 Centrifugal Chiller

State Name Off: All Systems Off: Alarm Off: Ambient Temperature Lockout Off: Panel Rocker Switch Off: Manual Off: Remote Switch Off: Remote Communications Off: Time Schedule Start Requested Waiting for Low Oil Sump Temperature Evaporator Pump Off Evaporator Pump On - Recirculation Evaporator Pump On - Cycle Timer Evaporator Pump On - Waiting for Load Oil Pump Off Oil Pump On - Pre-lubrication Condenser Pump Off Condenser Pump On - Waiting for Flow Compressor Motor - Start Up Unloading Compressor Motor - Started Compressor Motor - Running OK Compressor Motor - Rapid Shutdown Compressor Motor - Shut Down Unloading Compressor Motor - Off Normal Shut Down Condenser Pump - Off /Shut Down Evaporator Pump - Off/Shut Down Compressor Post Lubrication Oil Pump - Off/Shut Down

Value 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Read and Write Memory Location Table.

Description Capacity Limit Percent Clear Current Fault 0 = No Action 1 = Clear Fault Address 0475 041E Range (X) 0-100 0-1 Conversion % Units

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Description Chiller Operation Mode 0 = Stop 1 = Network Enable 2 = Recirculate 3 = Run Chilled Water Temperature Setpoint Communications Signal 0 = No Comm. 255 = Enable Comm. Outdoor Air Temperature BAS

Address 0477

Range (X) 0, 1, 2, 3

Conversion

Units

0476 047D 0473

0-160 0,255 60-252 253= N/A 255= Bad Sen.

X/2

°F

X - 100

°F

Read and Write Memory Definitions

All 0400 memory locations are stored in volatile memory and must be reset to desired value after a power loss. Capacity Limit Percent 0475 The capacity limit percent location is used to define the upper limit for unit cooling capacity. The normal value for this location is 100%, which enables maximum cooling. The unit's ability to cool may be reduced by setting the limit to less than maximum. The limit value is a percentage of full capacity. The valid range for this location is 0-100%. Clear Current Fault 041E The clear current fault location is used to clear the current active fault and re-initialize the unit controller. Writing a one to this location initiates this action. Once the fault has been cleared the controller will set this location back to zero. Never write to this memory location without investigating and correcting the cause of the fault Chiller Operation Mode 0477 The value in the chiller operation mode location is set to indicate the desired chiller operating mode. There are three possible values. Zero indicates "Stop"; the compressor and water pumps will turn off and all valves will close. A one indicates that the chiller is enabled for operation, it will start based upon sensed load. If there is no load the chiller will not start up. A two indicates "Recirculate"; the pumps will start and the valves will open to allow water to circulate through the system. However, the compressor will not start. A three indicates "Run"; the compressor and pumps will start and the valves will modulate as required. When in the lead/lag configuration, the control mode must be written to both the master and the slave units. Chilled Water Temperature Setpoint 0476 The chilled water temperature setpoint holds the temperature the leaving evaporator water will be cooled to if the unit is using this value for control. The data range of 0 to 160 corresponds to the temperature range of 0ºF to 80ºF with 0.5ºF resolution. The setpoint should not be set below 40ºF for standard temperature chiller units and may be set to 0°F for low temperature units. See: Chilled Water Temperature - Active Setpoint and Chiller Unit Temperature Type on page 10. Communications Signal 047D The communications signal location is used to indicate active network communications between the BAS network and the chiller unit. A value of 255 should be written to this location once every 60 seconds. If this location has not updated for five minutes, the chiller will assume there has been a loss of network communications and revert to internal setpoints for unit control.

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Series 200 Centrifugal Chiller

Outdoor Air Temperature - BAS 0473 The BAS outdoor air temperature location holds the value of the outdoor air temperature provided by the BAS network. The BAS network should write an 8-bit outdoor air temperature to this location. The valid range for this value is 60-252, which corresponds to -40ºF to 152ºF. See: Outdoor Air Temperature Method on page 17.

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Lead/Lag Load Balance Operation

Overview

The Master unit will select which unit should be the Lead unit (1) when both units are running, (2) when both units are off and (3) at the time and day selected, if any. Selection of the Lead unit takes effect the next time a start is requested and both chillers are off.

Read/Write Memory Locations

Point Name Addres s Master/Slave Setpoint 093C 0 = Master 1 = Slave (default) This memory address identifies a unit as either the Master or the Slave, for lead/lag purposes.1 The Master controls the lead/lag processing. This memory address controls the selection of the Lead unit. Range Description

Lead/Lag Mode Setpoint

093D

0 = Master is always Lead 1 = Slave is always Lead 2 = Auto-select (default) 0 - 100% (default = 95)

Enable Lag Setpoint

093E

If the Lead unit is running alone and its motor current exceeds this percentage of its RLA, the interstage timer will begin to run. When it expires, the Lag unit will turn on (unless the Lag unit has been designated as standby). If both the Lead and Lag units are running and the motor current of either drops below this percentage of its RLA, the interstage timer will begin to run. When it expires, the Lag unit will shut off. This memory address determines whether the Lag unit is to be used as a standby only. This memory address contains the day on which the Master should auto-select the Lead unit. This memory address contains the hour at which the Master should auto-select the Lead unit.

Disable Lag Setpoint

093F

0 - 100% (default = 40)

Lag Standby Setpoint

0942

0 = No (default) 1 = Yes 0 = N/A (default) 1 - 7 = Sunday Saturday 0 - 23 (default = 0)

Lead/Lag Switch Setpoint (Day) Lead/Lag Switch Setpoint (Hour)

0948

0949

1

Don't confuse the lead/lag terms "master" and "slave" with the configuration of communication ports as master ports or slave ports.

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Series 200 Centrifugal Chiller

Read Only Memory Locations

Point Name Lead/Lag Status Address 0401 Range 0 = Lead and Lag are off 1 = Lead in on 2 = Lag is on 3 = Lead and Lag are on 0 = Master 1 = Slave Same as Unit Status (0420) Same as Unit Status (0420) 0 - 100% 0 - 100% 0 = Lead is disabled 1 = Lead is enabled 0 = Lag is disabled 1 = Lag is enabled Description This memory address indicates which units are on.

Lead Unit Lead Unit Status Lag Unit Status Lead Motor Current Lag Motor Current Lead Status Lag Status

0402 0403 0404 0405 0406 0407 0408

This memory address indicates which unit is the Lead unit. Unit status of the Lead unit. Unit status of the Lag unit. Current drawn by Lead unit as a percentage of its RLA Current drawn by Lag unit as a percentage of its RLA Enabled/disabled status of the Lead unit. Enabled/disabled status of the Lag unit.

Series 200 Centrifugal Chiller

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Series 200 Centrifugal Chiller Simulator Package

Purpose

McQuay International offers hardware and software that will assist in the development of an open protocol interface. These tools will allow the designer to set up a simulated unit, read information from one communications port using McQuay Windows Monitor Simulation Software, and compare information from the BAS open protocol interface from a second communications port. If the BAS interface is working properly, the information read from the Windows Simulation Software will be identical to the information read by the BAS interface.

Development Tools

McQuay International offers the following tools to facilitate the development and testing of an Open Protocol interface for Series 200 centrifugal chillers. Literature: · McQuay "Open Protocol Data Communications - Data Packet Protocol" document dated February or latest update). Hardware required: McQuay offers the following hardware for development: · Model 250 controller(s) · Model 120 · RS-232 Communications Cable package · RS-485 Communication Cable package McQuay Open Protocol Monitor and Simulator software for Series 200 Centrifugal Chiller.. (version 1.0

Monitor Installation

The Microsoft® WindowsTM environment is required to run the McQuay Open Protocol Simulator Monitor software. Monitor software is currently available for download on McQuay On-line. The software is packaged in a self-extracting file which when executed, will install the software on your system.

Hardware Configuration

The desired hardware configuration for proving out an Open Protocol interface is shown below. In this arrangement, the Open Protocol interface to the BAS (Building Automation System) communications device is operational on the controller's Port A, and the McQuay Monitor program is running on a PC connected to the controller's Port B.

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Series 200 Centrifugal Chiller

For detailed wiring connections please consult McQuay Certified Drawing 573875Y.

Testing

Confirm that each data point that has been set up within the BAS interface is properly interpreted and displayed. This is done by comparing the BAS system values with the values displayed by the McQuay Monitor software. When checking a variable (by using the Support - Read/Write menu option or by clicking on the variable and using the "Change Value" dialog box), it is useful to test its high and low limits as well as values within its normal working range. For example, if a temperature is valid between -40.0 °F and 180°F, change the variable to -40°F and then 180°F. The chiller simulator control code and the Monitor program allow both read only and read/write variables to be modified to facilitate this kind of testing.Simulator Monitor Software Guide

Logging on to the software

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

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Communications Initialization

After 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 at connecting you will be at the main screen. If you are unsuccessful you will see the following:

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

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Series 200 Centrifugal Chiller

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

Downloading Simulation code

Once 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 find Download. Select Download and you should see the following screen:

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The controller address should be 00.ff in the case of a single unit connection. 00.ff is a special address which tells the software to connect to the direct connected controller regardless of the controller's address setting. Alternately, you may enter the address of the controller, however when trying 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 simulator code you wish to download to the controller. The data file is a temporary file in which controller data will be stored during the download process. This file may be deleted off of your hard drive after successful download. You must specify a data file name but the name of the file is arbitrary. The save options you should have checked are Port Configuration and Passwords. You should see the download progress dialog box after initiating the download:

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Series 200 Centrifugal Chiller

Monitoring a simulator controller

Once the code is properly downloaded into the simulator controller, you may begin to monitor memory locations in the Windows Simulator Monitor Software. From the Main Menu, choose Screen, and select Monitor Unit. Double-click the appropriate screen to start seeing simulator data.

Read/Write screens

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

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

Further Information on Windows Monitor Software

This document should get you started using Windows Monitor. You should not have to use any of the other functions of Windows Monitor in order to test your interface. If further information on Windows Monitor is required, please refer to McQuay International MicroTech Monitor 1.0 for Windows User's Manual.

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Series 200 Centrifugal Chiller

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

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