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Open Protocol Data Communications Packet Version 4.1 Group: Controls Date: March 1999 MicroTech Rooftop/RMC Data Information Packet for Open Protocol 1999 McQuay International

Revision History Version 4.1 3/99 Major formatting changes Removed several memory locations to avoid redundancy and confusion Added descriptions and diagrams for all types of network configurations Added in depth descriptions of rooftop control and memory locations Version 4.0 6/98 Dehumidification control has been added to the CAV Return Air/Zone Control (ART5) and the CAV 100% OAT/Zone Control (ART7) units Added OA Source Type $0939 Version 3.1 1/98 Software Identification strings have been corrected from version 3.0 of this document. Version 3.0 1/98 Software Identification strings have been updated to new versions Updated control mode definition. No change to variable, added information that keypad control mode needs to be set to auto in order for the control mode $044F to function Corrected error in current and previous alarm memory locations introduced in version 2.0 Added maximum static pressure setpoint $0915 Removed outside air damper Control $08D4 Added new option, humidity reset, for cooling reset type setpoint $0907 and corrected matrix from version 2.0 Added Network Supplied Outdoor Air Temperature $04E0 to allow the open protocol partner to override the units outdoor air sensor Version 2.0 7/97 Software Identification strings have been updated to new versions Created Windows version of simulator monitor software and also updated all simulator codes Current and previous alarm memory locations have been changed Remote exhaust fan status ($046F), and Exhaust Fan Stage ($0482) removed from all unit types Cooling Control Status - changed definition of status=0 Corrected Duct Static Pressure Setpoint limits Removed Outside Air Damper Control from the read/write points. This value typically is set at time of unit start-up. If this needs to be changed it is still available through the keypad display of the unit Removed input/output for each unit. If this information is desired, please consult the latest Installation and Maintenance manual (IM) for that particular unit Version 1.4 4/93 Repaginated and some extraneous verbiage removed from RMC section. No substantive changes Version 1.3 First publicly released version Notice Copyright 1999 McQuay International, Minneapolis MN 2 Rooftop/RMC Open Protocol Data Communications 4.1

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. Contents Revision History... 2 Contents... 3 Illustrations... 3 Overview... 5 Introduction... 5 Network Configuration with OPM... 5 Network Configuration with RMC... 6 Direct Connection to Single Rooftop Controller...7 Compatible Unit Control Software... 7 Supplemental Literature... 8 Conversions and Conventions... 8 Glossary of Terms... 9 Rooftop Control Capabilities... 9 RMC Panel Capabilities... 9 Control Options... 9 Rooftop Description of Operation... 11 Operating States... 11 Unit Transitions... 13 Controlling the Rooftop... 16 Network Control Features... 19 Open Protocol for the RMC Panel... 20 Features of the RMC Panel... 20 Controlling the RMC Through Open Protocol... 21 Rooftop Read Only Memory Locations... 23 Network Read Only variables... 31 Rooftop Read and Write Memory Locations... 32 Network Read/Write variables... 37 RMC Read Only Memory Locations... 39 RMC Read and Write Memory Locations... 41 Applied Rooftop Simulator Package... 44 Purpose... 44 Development Tools... 44 Monitor Installation... 44 Hardware Configuration... 44 Testing... 45 Simulator Monitor Software Guide... 46 Logging on to the software... 46 Communications Initialization... 46 Downloading Simulation code... 48 Monitoring a simulator controller... 49 Read/Write screens... 49 Further Information on Windows Monitor Software... 50 Illustrations Figure 1. Network Configuration with OPM...5 Rooftop/RMC Open Protocol Data Communications 4.1

Figure 2. Network Configuration with RMC...6 Figure 3. Direct Connection to Rooftop... 7 Figure 4. VAV Single Stage Heating Unit... 13 Figure 5. VAV/CAV Units with Return Fan... 14 Figure 6. CAV 100% Outside Air Units... 14 Figure 7. Dehumidification on CAV Zone Mixed Air or 100% Return Air... 15 Figure 8. Dehumidification on CAV Zone Control 100% Outdoor Air... 16 4 Rooftop/RMC Open Protocol Data Communications 4.1

Overview Introduction McQuay International Open Protocol for Rooftop/RMC allows other Building Automation System (BAS) companies the ability to communicate to a network of rooftop units or a single rooftop unit and obtain useful operating information via communication "reads" to the controller. In addition, remote control of the rooftop unit is possible by "writes" to the controller of new setpoints and commands. Multiple rooftop unit applications may have an open protocol master panel (OPM) or a remote monitoring and control panel (RMC) as their level one communications device. The OPM is used strictly for communications. The RMC is also used for communications and control functions for a group or groups of rooftop units. Please see below for more information on your specific network type. McQuay and their factory representatives are responsible for establishing communications from either the OPM or the RMC to all of the rooftop units. If there is no network, McQuay is responsible for setting up the single unit for open protocol. Part of the commissioning process is to determine the 8 character password needed for BAS communications, please contact the local McQuay representative for this information. McQuay commissions each open protocol job to insure that each network is error free on the McQuay side. If there are any communication problems, they are usually found in the BAS interface. Network Configuration with OPM Shown below is a typical Open Protocol Network for Rooftop Units. More detailed wiring schematics for all open protocol applications are located in McQuay s Certified Drawing 573875Y. This document is available upon request Figure 1. Network Configuration with OPM Level 1 OPM A BAS B Etc. Level 2 B RTU B RTU BAS - Building Automation System OPM - Open Protocol Master RTU - Rooftop Units RMC- Remote Monitor and Control The Open Protocol Master (OPM) panel provides a single communications port entry into the McQuay International Rooftop Unit network. Up to 64 Rooftop Unit Controllers may be accessed through a Rooftop/RMC Open Protocol Data Communications 4.1

single OPM panel. The OPM panel consists of a model 120 controller. The BAS communications device connects to Comm port A, which is pre-configured for RS-232, 9600 baud. For RS-485 communications on Comm port A, move the dip switch just above Comm port A to the RS-485 position. Port A is the Open Protocol communications port for the BAS communications device. Comm port B is a daisy chained, multi-drop, 9600 baud RS-485 proprietary McQuay International protocol. The Rooftop Unit controller is factory mounted. The unit controller provides pre-programmed, preengineered and pre-tested stand-alone control. There is one controller for each rooftop unit. Once the McQuay communication network has been commissioned and is totally functional, a communicating device from the BAS network may be installed. Note: The units continue to operate even when communications are lost; the network must be intact for the BAS to control the McQuay network. Network Configuration with RMC A Remote Monitoring and Control (RMC) panel can be substituted for an Open Protocol Master panel. Care must be taken to insure that writes to the RMC panel do not conflict with writes to the individual rooftop units. Consult the Operations Manual (OM) for the RMC for controls sequence. Shown below is a typical RMC Network for Rooftop Units. More detailed wiring schematics for all open protocol applications are located in McQuay s Certified Drawing 573875Y. This document is available upon request. Figure 2. Network Configuration with RMC Level 1 RMC A BAS B Etc. Level 2 B RTU B RTU The Remote Monitoring and Control (RMC) panel provides a single communications port entry into the McQuay International Rooftop Unit network. Up to 8 Rooftop Unit Controllers may be accessed through a single RMC panel. The RMC panel consists of a model 250 controller. The BAS communications device connects to Comm port A, which is pre-configured for 9600 baud. The pinout of the plug on Port A determines RS-232 or RS-485 communications. Please contact the McQuay representative to assure the correct plug is configured for your application. Comm port B is a daisy chained, multi-drop, 9600 baud RS-485 proprietary McQuay International protocol. The Rooftop Unit controller is factory mounted. The unit controller provides pre-programmed, preengineered and pre-tested stand-alone control. There is one controller for each rooftop unit. Once the McQuay communication network has been commissioned and is totally functional, a communicating device from the BAS network may be installed. Note: The units continue to operate even when communications are lost; the network must be intact for the BAS to control the McQuay network. 6 Rooftop/RMC Open Protocol Data Communications 4.1

Direct Connection to Single Rooftop Controller For each port available on the BAS communications device, a direct connection from to BAS communications device to the Rooftop can be established. Shown below is a typical diagram of a Direct Connection to a single Rooftop Unit. More detailed wiring schematics for all open protocol applications are located in McQuay s Certified Drawing 573875Y. This document is available upon request. Figure 3. Direct Connection to Rooftop BAS A Level 2 RTU The BAS communications device is directly connected to a single Rooftop unit.. The Rooftop unit consists of a model 250 controller. The BAS communications device connects to Comm port A on the Rooftop unit, which is pre-configured for 9600 baud. The pinout of the plug on Port A determines RS-232 or RS-485 communications. Please contact the McQuay representative to assure the correct plug is configured for your application. The Rooftop Unit controller is factory mounted. The unit controller provides pre-programmed, preengineered and pre-tested stand-alone control. There is one controller for each rooftop unit. Once the McQuay communication network has been commissioned and is totally functional, a communicating device from the BAS network may be installed. Note: The units continue to operate even when communications are lost; the network must be intact for the BAS to control the McQuay network. Compatible Unit Control Software You must know the IDENT of the unit controller software to know which variables are applicable. The software IDENT includes the version number (the third to the last and second to the last characters of the IDENT) of the software and its revision level (the last letter of the IDENT). Your McQuay representative can provide you with this information, or if the unit is already installed, the IDENT information can be read from the rooftop display. Note: Software revisions do not affect open protocol variables; however, software versions typically indicate a major change to the software. Usually, even software changes do not affect open protocol variables. This edition of the open protocol information packet is documented for the following revisions of the standard software. All subsequent revisions of the below versions will require a previously released open protocol information packet. If you encounter a later version of code, please refer to McQuay Online for an update to this document. In the table, the asterisk (*) can be any letter (i.e., revision). Rooftop/RMC Open Protocol Data Communications 4.1

Description Software IDENT Software Part Number VAV One Stage Heat/Fan Tracking VAV One Stage Heat/Space Pressure VAV Modulating Heat/Fan Tracking VAV Modulating Heat/Space Pressure ART1E06* ART1E05* ART2E04* ART2E03* ART3E06* ART3E05* ART4E04* ART4E03* 5016406* 5016405* 5031404* 5031403* 5016206* 5016205* 5031304* 5031303* CAV Return Air/Zone Control ART5E07* 5016307* CAV Return Air/SAT Control ART6E04* ART6E03* 5031504* 5031503* CAV 100% OAT/Zone Control ART7E07* 5016607* CAV 100% OAT/SAT Control ART8E04* ART8E03* 5031604* 5031603* Note: The first software IDENT is the latest version to be released. If you encounter the immediately preceding version (the second software identification listed) this document is also valid for those versions. 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. IM 483 OM 108 OM 109 OM 109/ Supp. #1 OM 110 IM - 444 OM - 121 Conversions and Conventions Note on Temperatures Installation & Maintenance Data Operation Manual (VAV Control, programs ART1, ART2, ART3, ART4) Operation Manual (CAV-ZTC Control, programs ART5, ART7) Operation Manual (Dehumidification/Reheat Control, programs ART5, ART7) Operation Manual (CAV-DTC control, programs ART6,ART8) Installation & Maintenance Data (Remote Monitoring and Control Panel) Operation Manual (Remote Monitoring and Control Panel) All temperatures are stated in degrees Fahrenheit, to get degrees Celsius, you must use the standard formula for temperature conversion: F C = 5 ( 32 ) 9 8 Rooftop/RMC Open Protocol Data Communications 4.1

Glossary of Terms Note on Pressures All pressures are stated in psi, to get KPA, you must use the following standard conversion: KPA = 689. PSI ART BAS IWC KPA OAT PSI RLA TCC Applied Rooftop Building Automation System Inches Water Columns Kilo-Pascal Outdoor Air Temperature Pounds Per Square Inch Rated Load Amps Temperature Control Company Rooftop Control Capabilities The following control capabilities are available for each unit. 1. Ability to clear active Fault conditions. 2. Ability to set the desired Operating Mode. 3. Ability to set occupied and unoccupied space temperature setpoints and associated differentials or deadbands. 4. Ability to set Supply Air Temperature setpoints, Duct Static Pressure setpoints, and associated deadbands in VAV units. 5. Ability to select type of automatic reset of temperature and pressure setpoints in VAV units. 6. Ability to set Economizer control parameters. 7. Ability to set temperature alarm limits. 8. Ability to set dehumidification setpoints in CAV/Zone Control units. Note: Depending on configuration, some of the above items are not applicable to certain units. RMC Panel Capabilities Control Options The following control capabilities are available for the RMC panel through the Open Protocol network: 1. Ability to program group configuration information. 2. Ability to set group control temperature parameters. 3. Ability to set group static pressure control parameters. There are eight versions of the Rooftop software to provide different control options. Variable Air Volume (VAV) units are controlled to maintain a specified supply air temperature. The airflow through the unit is varied in response to the requirements of VAV terminal units to maintain Rooftop/RMC Open Protocol Data Communications 4.1

the desired space conditions. The return vanes are controlled to maintain the space static pressure either by fan tracking or by direct space pressure control. 1. VAV units with One Stage of Heat provide a constant amount of heat to warm the space to the normal operating conditions. Normally, the space is warmed up once in the morning and then unconditioned air is recirculated through the space until cooling is required. The unit then provides supply air at the desired cooling setpoint. 2. VAV units with Modulating Heat provide heated, cooled, or unconditioned air to the space. When the space is cold, heated air is provided and the VAV terminal units open when the zone temperature gets too cool. When the space is warm, cool air is provided to the space and the VAV terminal units open when the zone temperature gets too hot. 3. The VAV unit types will have either fan tracking or direct space pressure control. Constant Air Volume (CAV) units supply a constant volume of air to the space. Units with Zone Control maintain a specified zone temperature by varying the temperature of the supply air. Units with Supply Air Temperature Control maintain the supply air temperature within defined limits. 1. CAV units with Return Air may have an economizer that provides free cooling when conditions permit and ventilation during occupied periods. 2. CAV units with 100% Outside Air have outside air dampers that are driven to the fully open position whenever the fan is turned on. 3. CAV units may have Zone Control or Supply Air Temperature. Direct Expansion and Chilled Water cooling is provided for all configurations. Gas, Hot Water, or Steam heat is provided for all configurations. Electric heat is provided for all configurations except VAV units with modulating heat. 10 Rooftop/RMC Open Protocol Data Communications 4.1

Rooftop Description of Operation Operating States The following sections describe the operation of the Applied Rooftops. For a more detailed description of operation and information on using the MicroTech unit controller, refer to the appropriate Manual. The unit operates in one of several states. Operation in most of these states is described below. The Start Requested state is a short duration transitional state. Calibrate and Balance are manual states used to commission the unit. Transitions between the states are discussed in the next section. Off In the Off state, fans, cooling, and heating are off. All dampers, vanes, and valves are driven closed. Startup Initializing This period allows vanes, outside air dampers, and valves to come into startup position before the unit starts. The Fan Operation Output is in the closed or fan on position. Relays driven by this output may be used to open internal isolation dampers or to open external smoke dampers before the fan starts. The Fan Operation Output remains in the closed or fan on position for all states except Off. Recirculation This period allows the unit airflow to stabilize before a decision is made to enter a cooling or heating state. When the unit enters this state, the supply fan is turned on, and the return fan, if provided, is turned on four seconds later. This delay reduces power droop due to multiple motors starting at the same time. Outdoor dampers remain closed. Cooling and Heating modes are disabled. The CAV unit with 100% outside air does not use this state. The unit goes directly to heating or fan only based on the outside air temperature. Morning Warm-up The purpose of this state is to raise the temperature of the space efficiently by keeping the outside air dampers closed. Control in this state is identical to the Unoccupied Heating state. Heating is on. Occupied Heating The only difference between Morning Warm-up and this state is that any Outdoor Air Damper is opened to the minimum position for ventilation. After the unit enters this state from Morning Warmup, Outdoor Air Dampers remain open to at least the minimum position until the unit is turned off at the end of the occupied period. The unit may reenter this state from Fan Only later in the occupied period if the space temperature drops sufficiently. Post Heat In this state, the Variable Inlet Vanes for the Supply fans are driven shut for two to three minutes before normal control is resumed. The VAV Box output remains in the Open position to keep the VAV boxes open while the Variable Inlet Vanes close. The purpose of this state is to prevent high duct pressures when VAV boxes that are wide open in heating suddenly close in response to low space temperatures when they are released to normal cooling control. Heating and Cooling are disabled. Rooftop/RMC Open Protocol Data Communications 4.1

Fan Only Heating The purpose of this state is to prevent cold air from being supplied to the space when the space temperature does not indicate the need for heat. Operation in this state may be required when the Minimum Outside Air Requirement is large. Discharge air temperature control units are controlled to maintain the Supply Air Temperature at the Cooling Supply Setpoint. Zone control units are controlled to maintain the Supply Air Temperature at the Fan On Heating Setpoint. The Fan on Heating Setpoint can only be changed from the rooftop controller. This state is not used in VAV units with one stage of heat. Fan Only The unit operates in this state when an acceptable space temperature can be maintained without either heating or cooling. Any outside air dampers are opened to the minimum position for ventilation in this state. Heating and Cooling are disabled. If a VAV unit enters this state immediately following the Occupied Heating or Unoccupied Heating state, the Variable Inlet Vanes for the Supply fans are driven shut for two to three minutes before normal control is resumed. The VAV Box output remains in the Open position to keep the VAV boxes open while the Variable Inlet Vanes close. This is to prevent high duct pressures when VAV boxes that are wide open in heating suddenly close in response to low space temperatures when they are released to normal cooling control. Heating and Cooling are disabled. Economizer In this state, the required cooling can be provided by supplying unconditioned outside air to the space. The outside air dampers are controlled to maintain the supply air temperature setpoint using the Step and Wait function. However, the dampers are not controlled below the edited minimum damper position. Fans are on. Mechanical Cooling When the unit is in this state, compressors or a chilled water coil is controlled to maintain the specified conditions. Heating is disabled. The outside air dampers are controlled either to the fully open position if the outside air is suitable for cooling or to the minimum position if it is not. Unoccupied Operation The unit has the capability of operating during unoccupied periods to keep the space temperature within unoccupied setpoints. Since ventilation is not required, the outdoor dampers normally remain closed in order to heat or cool the space more rapidly and efficiently. If outside air can be used to provide cooling, the outdoor dampers may be opened during the Unoccupied Economizer or Unoccupied Cooling state. Dehumidification The unit enters this state, the unit controls a DX or chilled water cooling coil to cool the air low enough to wring out moisture. Reheat is supplied as necessary to provide properly conditioned air to the space. The state the rooftop unit was in before entering dehumidification determines the reheat setpoint and outdoor damper position. The reheat setpoint is either the heating or the cooling control setpoint and the outdoor damper position is described in the above states. This state is only used in CAV Zone Control (ART5 and ART7) units. 12 Rooftop/RMC Open Protocol Data Communications 4.1

Unit Transitions Both VAV units and the CAV unit with a return fan transition from state to state as described in the chart on the next page. The CAV unit with 100% outside air does not have a Recirculation state. It transitions directly to one of the other states based on the outside air temperature. Figure 4. VAV Single Stage Heating Unit OFF Startup Initial Morning Warmup Unoccupied Economizer Recirculate Unoccupied Heating Unoccupied Cooling Economizer Cooling Fan ON Heating a0272 Rooftop/RMC Open Protocol Data Communications 4.1

Figure 5. VAV/CAV Units with Return Fan OFF Startup Initial Unoccupied Heating Unoccupied Economizer Unoccupied Cooling Recirculate Morning Warmup Economizer Fan ON Heating Cooling Fan ON Heating a0271 Figure 6. CAV 100% Outside Air Units OFF Unoccupied Cooling Startup Initial Unoccupied Heating Cooling Fan ON Heating Fan ON Heating a0273 14 Rooftop/RMC Open Protocol Data Communications 4.1

Figure 7. Dehumidification on CAV Zone Mixed Air or 100% Return Air Off Start-up Initialization Unoccupied Heating Unoccupied Cooling Recirculate Unoccupied Economizer Morning Warm-up Economizer Cooling Fan Only Fan On Heating Heating Dehumidification State Transitions Related to Dehumidification Operation Rooftop/RMC Open Protocol Data Communications 4.1

Figure 8. Dehumidification on CAV Zone Control 100% Outdoor Air Off Unoccupied Heating Unoccupied Cooling Start-up Initialization Fan On Heating Heating Cooling Fan Only Dehumidification State Transitions Related to Dehumidification Operation Controlling the Rooftop The following section outlines the control concepts of the rooftops. A complete list of variables is given in tabular format followed by their description later in this document. Caution: The control mode on Menu 12 of the rooftop keypad must be set to Auto. Failure to do so will prevent the BAS from properly controlling the rooftop unit. Control Mode This variable can be used to start and stop the unit. If this variable is set to 0, unit operation is disabled. If it is set to 2 or greater, the unit is turned on unless a shut down fault is active or the unit is manually disabled through the Keypad, Monitor program, or Remote Panel. Set this variable to 1 to put the unit in Auto mode. Auto mode will place the unit into an Unoccupied state and turned off unless ANY of the following are true: Unoccupied Heating or Unoccupied Cooling active (See Unoccupied Control in the appropriate OM) 16 Rooftop/RMC Open Protocol Data Communications 4.1

Internal Schedule On (Menu 25 on the rooftop keypad) External Override Switch On (Wired to terminals 101 and 102. See IM 483 for more information) Tenant Override active (Timer, default of 2 hours, set by pressing the tenant override button on thermostat) Note: The control mode on the unit keypad must be set to Auto for Control Mode to have any effect. If you find that changing the control mode through software does not seem to take effect, check the unit keypad display to insure the keypad control mode is set to Auto, these are two separate variables and the keypad control mode takes precedence. Dehumidification Control Dehumidification may be controlled on CAV Zone Control (ART5 and ART7) units. Dehumidification control can only be enabled through the rooftop keypad on Menu 18. The Humidity Control Type sets the dehumidification control variable to either humidity or dew point. If the humidity/dew point goes above setpoint, the unit begins dehumidification. On a call for dehumidification, the unit is staged up rapidly to the minimum dehumidification: cooling stage. After the dehumidification cooling timer expires (adjustable through keypad, default = 10 minutes), and there is still call for dehumidification, the unit is staged up rapidly to the maximum dehumidification cooling stage. When dehumidification requirements become satisfied, the unit is staged down in the reverse order. If the unit has chilled water cooling, the cooling valve is cycled 100% open on a call for dehumidification and cycle closed when dehumidification requirements are satisfied. See OM 109 Supp. #1 for more information. Discharge Air Temperature Control (Control Temperature) Discharge air temperature control starts with the Control Temperature Source memory location. The Control Temperature Source selects what factor will determine the heat/cool changeover. For example, if the Control Temperature Source is set to 0 (Return Temperature), the Control Temperature will be the return air temperature. The Control Temperature is compared to the Cooling Control Setpoint and the Heating Control Setpoint. If the Control Temperature is less than the Heating setpoint, the rooftop unit will enter a heat mode and control the discharge air temperature to the Heating Supply Setpoint. If the Control Temperature is greater than the Cooling Control Setpoint, the rooftop unit will enter a cool mode and control the discharge air temperature to the Cooling Supply Setpoint. Note: The term cool mode or heat mode is a figurative state only. It is not a readable state nor will it appear on the rooftop keypad. There are two unique conditions which need to be discussed: 1. The Control Temperature Source is set to None (ART6 and ART8 only). This will effectively place the rooftop into both a cool mode and allow the rooftop unit to control the discharge air temperature to the Cooling Supply Setpoint with either heating or cooling as needed. 2. The Control Temperature Source is set to Space Temperature (ART5 and ART7). The Space Setpoint Type can be set to either Thermostat (0) or Software (1) If set to Thermostat, the thermostat will control the Cooling Control Setpoint and the Heating Control Setpoint. If set to Software, the BAS will control the Cooling Control Setpoint and the Heating Control Setpoint. Rooftop/RMC Open Protocol Data Communications 4.1

Caution: The Space Setpoint Type can be set to Thermostat (0) no matter what value is written to the Control Temperature Source. This can lead to unexpected rooftop operation. The Space Setpoint Type should only be set to Thermostat (0) if the Control Temperature Source is set to Space. The unit will only activate cooling and control the Supply Air Temperature to the Cooling Supply Setpoint when in a cool mode. The unit will only activate heating and control the Supply Air Temperature to the Heating Supply Setpoint when in a heat mode. When the unit is in neither a cool nor heat mode ( Control Temperature is between the Cooling Control Setpoint and the Heating Control Setpoint), the unit generally will be in the Fan Only operating state in which neither heating nor cooling is active. There is one exception to this rule. When the unit is in the Fan Only operating state and the Supply Air Temperature falls below the Cooling Supply Setpoint, it will enter the Fan On Heating state in which the unit heating is activated to keep the Supply Air Temperature up at the Cooling Supply Setpoint (this is the discharge temperature low limit). See the appropriate OM for more information on Fan On Heating. Note: Fan On Heating is not available on ART1 or ART2 units Enthalpy and Economizer Changeover Low and high enthalpy is determined either through an enthalpy switch or as a function of the outdoor air temperature as defined by the Economizer Changeover Method. If the outdoor air temperature is used, the enthalpy is considered high if the outside air temperature rises above Economizer Changeover Temperature setpoint and switches to low if the outside air temperature drops below this setpoint by more than the differential. If the enthalpy switch is used, the enthalpy is high if the contact is open, low if the contact is closed. If the enthalpy is high, the economizer is locked out and mechanical cooling is used. If the enthalpy is low, the economizer is used as stage 0 cooling. The rooftop controller will use a step and wait algorithm to modulate the economizer. Outside Air Damper Control Fresh air in the space is controlled through the position of the outside air dampers. OA damper control is based on the Min Type field of Menu 21 on the keypad of the rooftop unit. The three options to the Min Type field affect OA damper control as follows: 1. If the Min Type field on the keypad is set to None, the Minimum Outside Airflow/Damper Position will control the minimum position of the OA damper. 2. If the Min Type field on the keypad is set to Auto, the Minimum Outside Airflow/Damper Position will control the minimum OA airflow. The rooftop unit controller uses an algorithm to adjust the OA damper position based on the minimum OA airflow and supply vane position. 3. If the Min Type field on the keypad is set to External, the OA dampers are controlled by an external signal wired to AI-14 (terminals 73 and 74). See appropriate OM for more information. On VAV units the position of the OA dampers can be set to a minimum position or set to a minimum airflow through the unit. On CAV units, there is always a constant airflow through the unit so the Min Type field on the keypad should always be None. 100% Outside Air units do not use these setpoints. Static Pressure Control Duct static pressure control is only used on VAV rooftop units (ART1, ART2, ART3, and ART4). The variable inlet vanes or inverter are used to control the airflow provided by the supply fan. The supply variable inlet vanes or inverter are modulated by the rooftop controller to maintain the duct static pressure at the Duct Static Pressure Setpoint. 18 Rooftop/RMC Open Protocol Data Communications 4.1

Another option is to have the BAS control the supply variable inlet vanes or inverter position directly. This is achieved by setting the Static Pressure Reset Type variable to 2 (Position Control). A non-zero value must be written to the Network Signal every minute or the Static Pressure Reset Type will revert to a value of 0 (No Reset). The BAS can set the Network Supply Vane Position to the desired variable inlet vanes or inverter position. This will allow the BAS to track the variable inlet vanes or inverter to the desired position. Caution: Networks using an RMC panel should not set the Static Pressure Reset Type to Position Control (2). The RMC panel uses this location to control the vane position of the rooftop units. The return variable inlet vanes or inverter are controlled based on rooftop unit type as follows: 1. ART1 and ART3 units control the return variable inlet vanes or inverter using fan tracking control. Fan tracking control will control the return variable inlet vanes or inverter based on the supply variable inlet vanes or inverter position. 2. ART 2 and ART4 use space static pressure control to control the return variable inlet vanes or inverter. The return variable inlet vanes or inverter are modulated by the rooftop controller to maintain the space static pressure at the Space Static Pressure Setpoint. Network Control Features You may want to uniformly control a network of rooftop units to allow for such configurations as common supply ducts. The rooftop units have features that allow for this type of control. These are: Network Supply Vane Position, Network Control Temperature, and Network OA Temperature. Note: These features require the BAS set the Network Signal variable to a non-zero value at least once per minute to maintain the Network Condition as Communicating. If the Network Condition reverts to Not Communicating, the Static Pressure Reset Type (if it is currently set to Network) reverts to None, the Control Temperature (if it is currently set to Network) reverts to Return Air, and the Network Supplied Outdoor Air Temperature (if it is currently set to Remote) reverts to Local. When network communications is restored, these locations revert back to their original values. Network Supply Vane Position The supply vane position normally is controlled to maintain the Static Pressure setpoint. However, if the Static Pressure Reset Type is set to Position Control, the supply vane position is controlled directly by the BAS to maintain the Network Supply Vane Position. Caution: Networks using an RMC panel should not set the Static Pressure Reset Type to Position Control (2). The RMC panel uses this location to control the vane position of the rooftop units. Network Control Temperature The Control Temperature Source is normally set to one of the unit temperatures- Return Temp, Space Temp, etc. However, if the Control Temperature is set to Network, the Control Temperature is set to the Network Control Temperature. This will give the BAS direct control over the Control Temperature. See Discharge Air Temperature Control (Control Temperature) for more information on Control Temperature. Rooftop/RMC Open Protocol Data Communications 4.1

Network Supplied Outdoor Air Temperature The OA Source Type is normally set to 0 (Local Control). However, if the OA Source Type is set to Remote, the BAS can write to the Network Supplied Outdoor Air Temperature which will pass its value to the Outdoor Air Temperature. This will give the BAS direct control over the Outdoor Air Temperature. Open Protocol for the RMC Panel A Remote Monitoring and Control (RMC) panel may be included in a rooftop network to provide remote keypad display capabilities and group control functions. The RMC panel is a level 1 controller capable of providing control functions for up to eight rooftop units. These rooftop units may be combined to form one to four groups that are then controlled in a common fashion. The group control features of the RMC panel can be accomplished by a BAS either by manipulating the RMC panel memory locations or by writing to the rooftop units directly. The memory locations needed for group control are listed in the Rooftop Read and Read/Write tables under the Network Read and Network Read/Write headings. Features of the RMC Panel The following section outlines the control features of the RMC panel available through Open Protocol. For more detail on any of these sections please refer to Bulletin No. IM 444, "MicroTech Applied Rooftop Remote Monitoring and Sequencing Panel." Control features of the RMC panel are: Common Duct Static Pressure Control Common Space Temperature Control Timeclock Scheduling Optimal Start Common Duct Static Pressure Control When a group of VAV rooftop units feeds a common supply air duct, the position of the variable inlet vanes on the supply fans or the speeds of the variable speed supply fan motors on the units need to be controlled together. The RMC unit sends a value of 0 to 100% to each unit in a selected group to indicate the desired position of the vanes or speed of the variable speed motor. This value is calculated using the Step and Change function, a group static pressure setpoint entered by the user, and a static pressure value determined by the RMC. The static pressure value is the average, minimum, or maximum on all applicable pressure sensors connected to the rooftop units in the group. When Position Control is selected as the type of reset for Static Pressure Reset Type, a unit will control to the vane position or speed as calculated by the RMC panel instead of the normal static pressure control. If communication between the RMC and a unit in a group selected for static pressure control is lost, the unit will operate in the normal manner using the static pressure sensor connected to that unit until network communication is restored. Common Space Temperature Control When a group of rooftop units feeds a common area, the units should be controlled as a single unit by responding to the same Control Temperature. A common Control Temperature is sent from the RMC to all rooftop units in each group. For each group, the user can select either Space or Return as the common Control Temperature. For each group 20 Rooftop/RMC Open Protocol Data Communications 4.1

the user can select the average, minimum or maximum of the selected temperature in each rooftop as the method for determining the common Control Temperature for the group. The rooftop unit will control to the common Control Temperature sent from the RMC whenever the user selects Network as the Control Temperature. If communication between the RMC and a unit with Network selected as the Control Temperature is lost, the unit will revert to normal operation using the Return Air Temperature as the Control Temperature Source until network communication is restored. Timeclock Scheduling The RMC panel features one eight day schedule just like the schedule in the rooftop unit. The user can select whether or not this schedule should be used for each of the eight rooftop units. The selection of units to be controlled by this schedule is unrelated to the groups and group functions. When the schedule is on, each unit selected for control by the schedule is sent a signal that places the unit in the occupied mode unless a higher priority control such as a Shut Down fault or Manual Off command will not allow it to start. The unit is turned off when this schedule is off and no other function such as timed override or another schedule call for the unit to be in the occupied mode. The RMC schedule can be set through the RMC panel keypad but is NOT available through Open Protocol. If scheduling is required though Open Protocol, it should be done by writing directly to the individual rooftop units. Optimal Start The user can select whether or not optimal start is to be used for each of the eight rooftop units. The selection of units to use the optimal start feature is unrelated to the groups and group functions. For each unit selected for optimal start, the RMC reads the minutes to occupancy from the Purge section of the Rooftop code. As is done in the current unit, the RMC uses the start history, outdoor air temperature, and space temperature to determine when each unit should start. When the time for a unit to start is reached, that unit is sent a signal that places the unit in the occupied mode unless a higher priority control such as a Shut Down fault or Manual Off command will not allow it to start. Optimal start can be set through the RMC panel keypad but is NOT available through Open Protocol. If optimal start is required though Open Protocol, it should be done by writing directly to the individual rooftop units. Controlling the RMC Through Open Protocol The following section outlines the control of the RMC panel through Open Protocol. Each of the Read/Write points (or groups of related points) is described. For a listing of the RMC unit Read/Write points see Appendix D. Control Temperature The control temperature setpoint indicates which temperature value to use as the Control Temperature Source. If this setpoint is set to $00, the Return Air temperature will be used as the common Control Temperature. If this setpoint is set to $01, the Space Air temperature will be used. Group Number This section combines rooftop units into groups for common control. Each unit may be assigned to a group 1-4. A $00 indicates that this unit is not associated with any group. Rooftop/RMC Open Protocol Data Communications 4.1

Number of Rooftop Units This value should be set to the number of rooftop units in the network. The program uses this value to determine if rooftop units are communicating. Rooftop units must have consecutive addresses starting with 01.00. Pressure Calculation The common Supply Vane Position sent to the rooftop units can be calculated based on the minimum, maximum, or average of all the static pressure values read. If this setpoint is set to $00, the minimum static pressure value is used in this calculation. A $01 will cause the maximum static pressure value to be used. A $02 will signal the RMC panel to average all the static pressure values read and use that value to compute a common Supply Vane Position. Pressure Setpoint This is the desired group Static Pressure Setpoint. The RMC panel will control the rooftop units to maintain this duct static setpoint by sending the units a supply vane position that will cause this pressure to occur. Temperature Calculation The common Control Temperature sent the rooftop units can be calculated to be the minimum, maximum, or average of all the temperatures read. If this setpoint is set to $00, the minimum temperature is used. A $01 will cause the maximum temperature to be used. A $02 will signal the RMC panel to average all the temperatures read and use that value as the common Control Temperature. 22 Rooftop/RMC Open Protocol Data Communications 4.1

Rooftop Read Only Memory Locations These are the memory locations that you will be able to read. The applied rooftop (ART) types that apply to the variables are: 1 = VAV/One Stage Heat 2 = VAV/One Stage Heat/Space Pressure Control 3 = VAV/Modulating Heat 4 = VAV/Modulating Heat/Space pressure Control 5 = Constant Volume/Return Air/Zone Control 6 = Constant Volume/Return/Supply Air Temp Control 7 = Constant Volume/100% Outside Air/Zone Control 8 = Constant Volume/100% Outside Air/Supply Air Temp Control Note: All temperature are in F unless otherwise noted. ART Number Variable Name Address (Hex) 1 2 3 4 5 6 7 8 Airflow Status 046C 0 = No Airflow 1 = Airflow Alarm, Current 0470 See Below Alarm, Current Date 0857 1-31 Alarm, Current Hour 0854 0-23 Alarm, Current Minute 0855 0-59 Alarm, Current Month 0856 1-12 Alarm, Current Year 0858 0-99 Alarm, Previous 1C00 Alarm, Previous Date 3 1-31 Alarm, Previous Hour 1 0-23 Alarm, Previous Minute 3 0-59 1C04 1C01 1C02 1 Valid for all ******2* and ******4* IDENTS. Rooftop/RMC Open Protocol Data Communications 4.1

ART Number Variable Name Address (Hex) 1 2 3 4 5 6 7 8 Alarm, Previous Month 3 1-12 Alarm, Previous Year 3 0-99 1C03 1C05 Control Temperature 0438 Cool or Heat Stage 043E Cooling Control Status 044B 0 = Off, Temp/Enthalpy Disable (economizer off on high enthalpy, compressor off on low temp) 1 = Off, Enable Switch 2 = Off, Schedule 3 = Off, Bridge 4 = Off, Network 5 = Off, Manual 6 = Off, Fault 7 = No Economizer 8 = Economizer Disabled, Hi Enthalpy 9 = Compressors Disabled, Low Temp 10 = Cool Enabled Cooling Operating Hours 08B3-08B4 Decimal value = 256 * High Byte + Low Byte Cooling Stage 04EC Dew Point Temperature 0480 Duct Static Pressure #1 Multiply by 0.02 to get IWC Duct Static Pressure #2 2 Multiply by 0.02 to get IWC Enthalpy Status 0 = Low Enthalpy 1 = High Enthalpy Fan Operating Hours Decimal value = 256 * High Byte + Low Byte Fan Operation Output 0 = Off 1 = On 0433 0434 0448 08B0-08B1 0474 24 Rooftop/RMC Open Protocol Data Communications 4.1

ART Number Variable Name Address (Hex) 1 2 3 4 5 6 7 8 Heating Control Status 044C 0 = Off, Enable Switch 1 = Off, Bridge 2 = Off, Network 3 = Off, Manual 4 = Off, Fault 5 = Heat Enabled 6 = Off, High Temperature 7 = Off, Schedule Heating Operating Hours 08B6-08B7 Decimal value = 256 * High Byte + Low Byte Heating Stage 04EB Humidity Humidity in Percent 0433 Miscellaneous Temp #1 2 042C Miscellaneous Temp #2 2 042D Mixed Air Temperature 3 042B Outdoor Air Damper Position 0432 Outdoor Air Damper Position in Percent Outdoor Air Temperature 0429 Subtract 100 to get F Override Hours 08B9-08BA Reheat Operating Hours 080D-080E Decimal value = 256 * High Byte + Low Byte Reheat Setpoint 0906 Reheat Stage 0C24 Return Air Temperature 0428 Return Fan Status 046E 0 = Off 1 = On Return Fan Vane Position 0431 Return Fan Vane Position in Percent Space Air Temperature 042A 2 Optional 3 Optional except on units with Gas or Electric heat Rooftop/RMC Open Protocol Data Communications 4.1

ART Number Variable Name Address (Hex) 1 2 3 4 5 6 7 8 Space Static Pressure 0434 To get pressure in IWC first multiply by 0.002 then subtract 0.250. Range: -0.250 to +0.250 Supply Air Temperature 0427 Supply Fan Status 046D 0 = Off 1 = On Supply Fan Vane Position 0430 Supply Fan Vane Position in Percent Unit Status 0472 0 = Program Inactive 1 = Off, Fan Switch 2 = Off, Unoccupied 3= Off, Network 4 = Off, Manual 5 = Off, Service 6 = Off, Alarm 7 = Calibrate 8 = Start Requested 9 = Startup Initialize 10 = Recirculation 11 = Fan On 12 = Balance 13 = Unoccupied Heating 14 = Unoccupied Heating Stage xx 15 = Morning Warm-up 16 = Morning Warm-up Stage xx 17 = Heating 18 = Heating Stage xx 19 = Post Heat 20 = Economizer 21 = Mechanical Cooling 22 = Mechanical Cooling Stage xx 23 = Fan On with Heating 24 = Fan On with Heating Stage xx 25 = Unoccupied Economizer 26 = Unoccupied Cooling 27 = Unoccupied Cooling Stage xx 28 = Dehumidify VAV Box Output 046B 0 = Off, Heating 1 = On, Cooling Airflow Status $046C The airflow status indicates whether or not there is airflow from the supply fan. A 0 indicates that there is no flow. A value of 1 indicates there is airflow. Alarm, Current $0470 26 Rooftop/RMC Open Protocol Data Communications 4.1

The Alarm, Current variable indicates what alarm condition is affecting the rooftop unit. Alarms are shown in increasing priority. A higher priority alarm can automatically clear a lower priority alarm. An active alarm always has a higher priority than a cleared alarm. Warnings indicate that an abnormal condition exists, but no automatic action is taken. Warnings are cleared automatically when the warning condition is corrected. The exception to this rule is the Stuck Damper warning which must be cleared manually. Problems indicate that MicroTech or mechanical safeties have disabled one or more functions in the unit, but the unit continues to operate. Problems are also self-clearing. When a Fault occurs, the unit is turned off. Faults must be cleared manually to restart the unit. Active Alarm Condition Value 0 No Alarms Active Alarm Warning Condition Value 1 Misc. Temp Sensor # 1 Shorted or Open 2 Misc. Temp Sensor # 2 Shorted or Open 3 Final Filter Dirty. 4 Standard Filter Dirty. 5 Airflow Warning- Unit is off and digital input indicates airflow 6 OA Damper Stuck. Either the damper is open when the unit is off or the damper is not completely open when it should be. Active Alarm Problem Condition Value 7 Cooling Circuit # 1 Failure 8 Cooling Circuit # 2 Failure 9 Cooling Circuit # 3 Failure 10 Heat Fail. Only for units with gas heat 11 Low Airflow. Temperature rise across heater is too high. Heat disabled. VAV Units only. 12 Mixed Air Temp sensor shorted or open 13 Supply Air Temp sensor shorted or open 14 Return Air Temp sensor shorted or open 15 Space Temp sensor shorted or open 16 Outdoor Air Temp sensor shorted or open 17 Freeze Problem. Digital Freeze Input closes after unit is turned off. Active Alarm Fault Condition Value 18 Supply Vanes open when unit attempts to start. VAV units only. 19 Fan Fail. Airflow switch open after unit is on. 20 Supply Temp below low limit after unit is on. 21 Supply Temp above high limit after unit is on. Rooftop/RMC Open Protocol Data Communications 4.1

Active Alarm Fault Condition Value 22 Return Temp above high limit after unit is on. 23 Duct High Limit Switch open. VAV units only. 24 Supply Air Temp sensor shorted or open 25 Return Air Temp sensor shorted or open and is selected as the Control Temperature 26 Space Temp sensor shorted or open and is selected as the Control Temperature 27 Outside Air Temp sensor shorted or open and is selected as the Control Temperature. VAV with Modulating Heat only. 28 Smoke Detector input open 29 Freeze Shutdown. Digital Freeze input closes while unit is operating. Alarm, Current Date $0857 Alarm, Current Hour $0854 Alarm, Current Minute $0855 Alarm, Current Month $0856 Alarm, Current Year $0858 The above locations form the time stamp of the current alarm Alarm, Previous $1C00 This is the previous alarm. Refer to Alarm, Current. Alarm, Previous Date $1C04 Alarm, Previous Hour $1C01 Alarm, Previous Minute $1C02 Alarm, Previous Month $1C03 Alarm, Previous Year $1C05 The above locations form the time stamp of the previous alarm Control Temperature $0438 This memory location is the heat/cool changeover temperature equal to the Return, Space, or OA Temperature specified by the Control Temperature Source. For example, if the Control Temperature Source was set to 0 (Return Temperature), the Control Temperature would provide the return temperature. See Discharge Air Temperature Control (Control Temperature) under Controlling the Rooftop for more information. Cool or Heat Stage $043E This memory location is the heat or cool stage number. See Unit Status to determine if the rooftop is actually in heating or cooling. ART5 and ART7 units should use the Cooling Stage and Heat Stage locations in lieu of the Cool or Heat Stage. Cooling Control Status $044B This memory location is the cooling status of the rooftop. The Cooling Control Status will only display the highest priority status. The higher the value the higher the priority level. Cooling Operating Hours $08B3-08B4 This memory location will indicate the number of hours of cooling. Multiply the high byte by 256 and add the low byte to obtain a value in hours. 28 Rooftop/RMC Open Protocol Data Communications 4.1

Cooling Stage $04EC This memory location is only used in CAV Zone Control units (ART5 and ART7). This is the operating cooling stage in the rooftop. Dew Point Temperature This is the dew point temperature of the space or return air. The dew point temperature is derived by the rooftop controller from the humidity sensor. The field Control= in Menu 18 on the keypad tells the software the physical location of the humidity sensor (Return or Space). See Dehumidification Control under Controlling the Rooftop and OM 109 Supp, #1 for more information. Duct Static Pressure #1 $0433 This memory location is the Duct Static Pressure. Multiply this value by 0.02 to obtain a value in IWC. Duct Static Pressure #2 $0434 This memory location is the Duct Static Pressure. Multiply this value by 0.02 to obtain a value in IWC. Duct Static Pressure #2 can only be used on ART1 and ART3 units. The rooftop controller will use the lower value between the Duct Static Pressure #1 and Duct Static Pressure #2 for control purposes. Enthalpy Status $0480 This memory location determines if the OA is suitable for economizer use. A high enthalpy reading will lock out the economizer. See Enthalpy and Economizer Changeover under Controlling the Rooftop for more information. Fan Operating Hours $08B0-08B1 This memory location is the operating and override hours of the supply fan. Multiply the high byte by 256 and add the low byte to obtain a value in hours. Fan Operation Output $0474 The Fan Operation State indicates that the fans are either on or will be started in 3 minutes. When this location switches from an off state to an on state, the fans will start in 3 minutes (provided no alarm condition arises). The Fan Operation State will remain on until the fans shut off. The Fan Operation Status can be used to interlock a damper with the fans. Heating Control Status $044C This memory location is the heating status of the rooftop. The Heating Control Status will only display the highest priority status. The higher the value the higher the priority level. Heating Operating Hours $044C This memory location will indicate the number of hours of cooling. Multiply the high byte by 256 and add the low byte to obtain a value in hours. Heating Stage $04EB This memory location is only used in CAV Zone Control units (ART5 and ART7). This is the operating heating stage in the rooftop Humidity $0433 This is the relative humidity percent of the space or return air. The field Control= in Menu 18 on the keypad tells the software the physical location of the humidity sensor (Return or Space). See Dehumidification Control under Controlling the Rooftop for more information. Miscellaneous Temp #1 $042C Miscellaneous Temp #2 $042D Rooftop/RMC Open Protocol Data Communications 4.1

These memory locations indicate the temperature of an optional sensor. This temperature is used for monitoring only. Miscellaneous temperature sensor #1 is wired to terminals 122 and 123. Miscellaneous temperature sensor #2 is wired to terminals 124 and 125. Mixed Air Temperature $042B This memory location is the mixed air temperature. It is used on rooftop units with gas and electric heat only. Outdoor Air Damper Position $0432 This memory location is the OA damper position in percent. Outdoor Air Temperature $0429 This memory location is the OA temperature. Subtract 100 from this value to get F. Override Hours $08B9-08BA This memory location is the number of hours the rooftop has been in tenant override. Multiply the high byte in 256 and add the low byte to obtain a value in hours. Reheat Operating Hours $080D-080E This memory location is the number of hours the rooftop has been in reheat. Multiply the high byte in 256 and add the low byte to obtain a value in hours Reheat Setpoint $0906 The reheat setpoint is set equal to the cooling or heating setpoint, depending on rooftop conditions. See Dehumidification Control under Controlling the Rooftop. Reheat Stage $0C24 This memory location is only used in CAV Zone Control units (ART5 and ART7). This is the operating reheat stage in the rooftop Return Air Temperature $0428 This memory location is the return air temperature. Return Fan Status$046E The Return Fan Status indicates whether or not the return fan is energized. Space Static Pressure $0434 The Space Static Pressure is the static pressure in the space. Multiply this value by 0.002 and subtract 0.250 to obtain a value with IWC units. The Space Static Pressure has a range of -0.250 to +0.250. Space Air Temperature $042A This memory location is the space air temperature. Supply Air Temperature $0427 This memory location is the supply air temperature. Supply Fan Status $046d The Supply Fan Status indicates whether or not the supply fan is energized. Supply Fan Van Position $0430 This memory location is the supply fan vane position in percent Unit Status $0472 The Unit Status indicates the operating state of the rooftop. See the Rooftop Description of Operation for more information on these states. 30 Rooftop/RMC Open Protocol Data Communications 4.1

VAV Box Output$046B The VAV Box Output will indicate whether the rooftop is in heating or cooling. Network Read Only variables Variable Name Address 1 2 3 4 5 6 7 8 Network Condition 0 = Not Communicating 1 = Communicating 0461 Network Condition $0461 The Network Condition indicates whether or not proper communication to the rooftop exist. Rooftop/RMC Open Protocol Data Communications 4.1

Rooftop Read and Write Memory Locations These are the memory locations that you are able to read and write. The unit types that apply to the variables are: 1 = VAV/One Stage Heat 2 = VAV/One Stage Heat/Space Pressure Control 3 = VAV/Modulating Heat 4 = VAV/Modulating Heat/Space pressure Control 5 = Constant Volume/Return Air/Zone Control 6 = Constant Volume/Return/Supply Air Temp Control 7 = Constant Volume/100% Outside Air/Zone Control 8 = Constant Volume/100% Outside Air/Supply Air Temp Control Note: All temperature are in F unless otherwise noted. Variable Name Alarm Clear 4 0 = No 1 = Yes Control Mode 0 = Off, No Unoccupied Operation 1 = Auto 2 = On, Cool and Heat Enabled 3 = On, Cool Enabled, Heat Disabled 4 = On, Cool Disabled, Heat Enabled 5 = On, Cool and Heat Disabled Control Temperature Source 0 = Return Temperature 1 = Space Temperature 2 = Network 5 3 = OAT 4 = None Addres s Limit (default) 1 2 3 4 5 6 7 8 0444 0-1 (0) 044F 0-5 (1) 0898 0-4 (0) Cooling Control Deadband 08D8 0-10 (1) Cooling Control Differential 0906 1-10 (2) Cooling Control Setpoint 0905 55-99 (75) Cooling Supply Deadband 08CB 0-10 (1) Cooling Supply Setpoint 090C 40-100 (55) 4 Will revert to No after alarm has been cleared 5 Will revert to Return Temperature if Network Signal is lost for more than 1 minute 32 Rooftop/RMC Open Protocol Data Communications 4.1

Variable Name Dehumidification: Maximum Cooling Stage Dehumidification: Minimum Cooling Stage Addres s Limit (default) 1 2 3 4 5 6 7 8 0941 0-8 0940 0-8 Dew Point Deadband 093F 0-10 (2) Dew Point Setpoint 093E 0-87 (50) Duct Static Pressure Deadband 0831 0-25 (4) Duct Static Pressure Setpoint 0916 10-200 (50) Economizer Changeover Differential 0919 1-10 (1) Economizer Changeover Method 087B 0-1 (1) 0 = Based on OAT 1 = Enthalpy Switch Economizer Changeover Temperature Setpoint Subtract 100 from value to get F 0918 100-200 (160) Heating Control Deadband 08DF 0-10 (1) Heating Control Differential 0904 1-10 (2) Heating Control Setpoint All setpoints in Degrees F 0903 40-99 (70) Heating Supply Deadband 084D 0-10 (1) Heating Supply Setpoint 0913 40-140 (100) Humidity Control Type 092F 0-1 (0) 0 = Humidity 1 = Dew Point Humidity Deadband 0920 0-10 (2) Humidity Setpoint 091F 0-100 (50) Minimum Outside Airflow/Damper Position 0-100% OA Source Type 0 = Local 2 = Remote Space Setpoint Type 0 = Thermostat 1 = Software 0897 0-100 (10) 0939 0, 2 (0) 087E 0-1 (1) Space Static Pressure Deadband 0838 0-50 (3) Rooftop/RMC Open Protocol Data Communications 4.1

Variable Name Addres s Limit (default) 1 2 3 4 5 6 7 8 Space Static Pressure Setpoint 0928 0-250 (150) Static Pressure Reset Type 0914 0,2 (0) 0 = No Reset 2 = Position Control 6 Unoccupied Cooling Space Differential 0925 1-10 (3) Unoccupied Cooling Space Setpoint 0924 55-99 (85) Unoccupied Heating Space Differential 0902 1-10 (3) Unoccupied Heating Space Setpoint 0901 40-99 (55) Alarm Clear $0444 To clear an active fault in the unit, set this variable to 1. After clearing the alarm, the program sets this memory location back to zero. Alarms are divided into three categories according to severity- Warnings, Problems, and Faults. Warnings and problems are normally self-clearing once the abnormal condition is resolved. Faults cause the unit to shut down and must be manually cleared. Control Mode $044F The Control Mode is used to control the operating state of the rooftop. See Control Mode under Controlling the Rooftop for more information. Control Temperature Source $0898 The Control temperature Source determines what parameter the rooftop will use to determine if it is in a cool or heat mode. See Discharge Air Temperature Control (Control Temperature) under Controlling the Rooftop for more information. Cooling Control Deadband $08D8 The Cooling Control Deadband is used to create a deadband on the Cooling Control Setpoint for ART5 and ART7 units. Cooling Control Differential $0906 The Cooling Control Differential is used to create a differential on the Cooling Control Setpoint for all units except ART5 and ART7. Cooling Control Setpoint $0905 The rooftop unit uses the Cooling Control Setpoint to determine if it should go into the cooling mode. The rooftop unit will go into the cooling mode if the Cooling Control Temperature is greater than the Cooling Control Setpoint. The rooftop will leave the cooling mode when the Cooling Control Temperature is less than the Cooling Control Setpoint minus the Cooling Control Differential or the Cooling Control Deadband depending on the type of rooftop unit. See Discharge Air Temperature Control (Control Temperature) under Controlling the Rooftop for more information. Cooling Supply Deadband The Cooling Supply Deadband is used to create a deadband on the Cooling Supply Setpoint $08CB 6 Will revert to No Reset if Network Signal is lost for more than 1 minute 34 Rooftop/RMC Open Protocol Data Communications 4.1

Cooling Supply Setpoint $090C The Cooling Supply Setpoint is only used if the rooftop unit is in cooling mode as determined by the Cooling Control Setpoint. The exception to this is ART6 or ART8 units set to a Control Temperature of None which always have an active Cooling Supply Setpoint. If the Cooling Supply Setpoint is active, the rooftop controller will compare the Cooling Supply Setpoint to the Supply Air Temperature. If the Supply Air Temperature is greater than the Cooling Supply Setpoint, the rooftop will go into the first stage of cooling (or economizer if available). This location is only adjustable if Menu 13 on the rooftop keypad is set to No Reset. Dehumidification: Maximum Cooling Stage $0941 The Dehumidification: Maximum Cooling Stages sets the maximum cooling stages for dehumidification. See Dehumidification Control under Controlling the Rooftop for more information. Dehumidification: Minimum Cooling Stage $0940 The Dehumidification: Minimum Cooling Stages sets the minimum cooling stages for dehumidification. See Dehumidification Control under Controlling the Rooftop for more information. Dew Point Deadband $093F The Dew Point Deadband is used to create a deadband on the Dew Point Setpoint. See Dehumidification Control under Controlling the Rooftop for more information. Dew Point Setpoint $093E The Dew Point Setpoint is only used if the Humidity Control Type is set to Dew Point. The Dew Point Setpoint used to control dehumidification. See Dehumidification Control under Controlling the Rooftop for more information. Duct Static Pressure Deadband $0831 The Duct Static Pressure Deadband is used to create a deadband on the Duct Static Pressure Setpoint Duct Static Pressure Setpoint $0916 The Duct Static Pressure Setpoint is used to control the static pressure in the duct. Multiply this value by 0.02 to obtain a value in IWC. See Duct Static Pressure Control under Controlling the Rooftop for more information. Economizer Changeover Differential $0919 The Economizer Changeover Differential is added to the Economizer Changeover Temperature to create a differential. Economizer Changeover Method $087B The Economizer Changeover Method is used to determine what factor (OAT or Enthalpy Switch) will enable/lockout the economizer. See Economizer Control under Controlling the Rooftop for more information. Economizer Changeover Temperature Setpoint $0918 The Economizer Changeover Temperature is only used if the Economizer Changeover Method is set to Based on OAT. If the Outdoor Air Temperature is greater than the Economizer Changeover Temperature Setpoint plus the Economizer Changeover Differential, the economizer is disabled. If the Outdoor Air Temperature is less than the Economizer Changeover Temperature Setpoint, the economizer is enabled. See Enthalpy and Economizer Control under Controlling the Rooftop for more information. Heating Control Deadband $08DF The Heating Control Deadband is used to create a deadband on the Heating Control Setpoint for ART5 and ART7 units. Rooftop/RMC Open Protocol Data Communications 4.1

Heating Control Differential $0906 The Heating Control Differential is used to create a differential on the Heating Control Setpoint for all units except ART5 and ART7. Heating Control Setpoint $0905 The rooftop unit uses the Heating Control Setpoint to determine if it should go into the heating mode. The rooftop unit will go into the heating mode if the Heating Control Temperature is less than the Heating Control Setpoint. The rooftop will leave the heating mode when the Heating Control Temperature is greater than the Heating Control Setpoint minus the Heating Control Differential or the Heating Control Deadband depending on the type of rooftop unit. See Discharge Air Temperature Control (Control Temperature) under Controlling the Rooftop for more information. Heating Supply Deadband The Heating Supply Deadband is used to create a deadband on the Heating Supply Setpoint $08CB Heating Supply Setpoint $090C The Heating Supply Setpoint is only used if the rooftop unit is in heating mode as determined by the Heating Control Setpoint. The exception to this is ART6 or ART8 units set to a Control Temperature of None which always have an active Heating Supply Setpoint. If the Heating Supply Setpoint is active, the rooftop controller will compare the Heating Supply Setpoint to the Supply Air Temperature. If the Supply Air Temperature is greater than the Heating Supply Setpoint, the rooftop will go into the first stage of heating. This location is only adjustable if Menu 14 on the rooftop keypad is set to No Reset. Humidity Control Type $092F The Humidity Control Type is used to determine what factor (Humidity or Dew Point) will be used to control dehumidification. See Dehumidification Control under Controlling the Rooftop for more information. Humidity Control Deadband $0920 The Humidity Control Deadband is used to create a deadband on the Humidity Control Setpoint for ART5 and ART7 units. Humidity Setpoint $091F The Humidity Setpoint is only used if the Humidity Control Type is set to Humidity. The Humidity Setpoint is used to control dehumidification. See Dehumidification Control under Controlling the Rooftop for more information. Minimum Outside Airflow/Damper Position $0897 The Minimum Outside Airflow/Damper Position will either control the actual damper position percent or the percent of outside airflow depending on the value set to the Min Type field of Menu 21 on the rooftop keypad. See Outside Air Damper Control under Controlling the Rooftop for more information. OA Source Type $0939 The OA Source Type is used to determine what factor (Local or Remote) will be used for the Outdoor Air Temperature. A value of Local will used sensor wired to terminals 60 and 61 on the rooftop controller for the Outdoor Air Temperature value. A value of Remote is only valid if the Network Signal is being written to every minute. If the OA Source Type is set to Remote and the Network Signal is being written to every minute, the Network Supplied Outdoor Air Temperature can be used. See Network Supplied Outdoor Air Temperature and Network Control Features under Controlling the Rooftop. Space Setpoint Type $087E 36 Rooftop/RMC Open Protocol Data Communications 4.1

The Space Setpoint Type is only valid on ART5 and ART7 units and if the Control Temperature Source is set to Space Temperature. The Space Setpoint Type is used to determine what factor (Thermostat or Software) will be used to control Space Setpoint. A value of Thermostat will use the thermostat setpoints to determine whether the rooftop unit will go into a heat or cool mode. A value of Software will allow the BAS to use the Cooling Control Setpoint and the Heating Control Setpoint to determine whether the rooftop unit will go into a heat or cool mode. See Discharge Air Temperature Control (Control Temperature) under Controlling the Rooftop for more information. Space Static Pressure Deadband $0838 The Space Static Pressure Deadband is used to create a deadband on the Space Static Pressure Setpoint for ART2 and ART4 units Space Static Pressure Setpoint $0928 The Space Static Pressure Setpoint is used to control the static pressure in the space. Multiply this value by 0.02 to obtain a value in IWC. See Space Static Pressure Control under Controlling the Rooftop for more information. Static Pressure Reset Type $0914 The Static Pressure Reset Type is only valid on VAV units (ART1, ART2, ART3, and ART4). The Static Pressure Reset Type defaults to 0 which indicates No Reset. A value of Position Control will allow the BAS to control the supply vane position. See Network Supply Vane Position and Network Control Features under Controlling the Rooftop. Unoccupied Cooling Space Differential $0902 The Unoccupied Cooling Space Differential is used to create a differential on the Unoccupied Cooling Space Setpoint. Unoccupied Cooling Space Setpoint $0901 The Unoccupied Cooling Space Setpoint is the setpoint used to determine if the rooftop unit should go into the cool mode when the rooftop is in the unoccupied state. Unoccupied Heating Space Differential $0902 The Unoccupied Heating Space Differential is used to create a differential on the Unoccupied Heating Space Setpoint. Unoccupied Heating Space Setpoint $0901 The Unoccupied Heating Space Setpoint is the setpoint used to determine if the rooftop unit should go into the heat mode when the rooftop is in the unoccupied state. Network Read/Write variables. Variable Name Addres s Limits 1 2 3 4 5 6 7 8 Network Control Temperature 0443 40-100 Network Signal 044E 1-255 Network Supplied Outdoor Air Temperature Subtract 100 to get F Network Supply Vane Position 0-100% 04E0 0-255 044D 0-100 Rooftop/RMC Open Protocol Data Communications 4.1

Network Control Temperature $0443 The Network Control Temperature is only valid if the Control Temperature Source is set to Network and a non-zero value is written to the Network Signal every minute. The Network Control Temperature allows the BAS to send a value directly to the Control Temperature instead of using a local sensor. If the Network Signal times out, the Control Temperature Source reverts back to Return Temperature. See Network Control Features under Controlling the Rooftop for more information. Network Signal $044E If using Network Control Temperature, Network Supplied Outdoor Air Temperature. or Network Supply Vane Position. a non-zero value must be written to the Network Signal every minute. If the Network Signal times out, network variables revert back to default parameters. See Network Control Features under Controlling the Rooftop for more information. Network Supplied Outdoor Air Temperature $04E0 The Network Supplied Outdoor Air Temperature is only valid if the OA Source Type is set to Network and a non-zero value is written to the Network Signal every minute. The Network Supplied Outdoor Air Temperature has an offset of 100 to allow negative outdoor air temperatures. For example a 90 written to this location will result in a 10 degrees outdoor air temperature. If the Network Signal times out, the outdoor air temperature reverts back to local value. See Network Control Features under Controlling the Rooftop for more information. Network Supply Vane Position $044D The Network Supply Vane Position is only valid if the Static Pressure Reset Type is set to Network - Position Control and a non-zero value is written to the Network Signal every minute. The Network Supply Vane Position will directly control the supply vane position percent. 38 Rooftop/RMC Open Protocol Data Communications 4.1

RMC Read Only Memory Locations Variable Name Group Control Temperature Group #1 Group #2 Group #3 Group #4 Group Speed/Vane Position (%) Group #1 Group #2 Group #3 Group #4 Group Static Pressure Group #1 Group #2 Group #3 Group #4 Schedule Status 0 = Unoccupied 1 = Occupied 047E 047F 0480 0481 0486 0487 0488 0489 0482 0483 0484 0485 0495 Address Group Control Temperature Group #1 $047E Group #2 $047F Group #3 $0480 Group #4 $0481 The Group Control Temperature memory locations list the control temperature associated with each group. The Group Control Temperature is the heat/cool changeover temperature equal to the Return or Space specified by the Group Control Temperature Source for the appropriate group number. For example, if the Control Temperature Source was set to 0 (Return Temperature), the Group Control Temperature would provide the return temperature. See Features of the RMC for more information. Group Speed/Vane Position (%) Group #1 $0486 Group #2 $0487 Group #3 $0488 Group #4 $0489 The Group Speed/Vane Position is the speed or vane position setpoint as calculated by the RMC. The RMC uses the Group #? Pressure Calculation and Group #? Pressure Setpoint to calculate the Group Speed/vane Position (%). Group Static Pressure Group #1 $0482 Group #2 $0483 Group #3 $0484 Group #4 $0485 The Group Static Pressure is calculated by the RMC based on the Group #? Pressure Calculation. See Group #? Pressure Calculation for more information. Schedule Status $0495 Rooftop/RMC Open Protocol Data Communications 4.1

If the rooftop units are setup at their keypad to receive a time schedule from the RMC, the Schedule Status will place the rooftop units into Occupied or Unoccupied. See Features of the RMC for more information. 40 Rooftop/RMC Open Protocol Data Communications 4.1

RMC Read and Write Memory Locations Variable Name Limits Address Group #1: Control Temperature Source 0 = Return 1 = Space Temperature Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Setpoint Pressures in 0.02 IWC increments from 0 to 200 * 0.02 = 4.00 IWC Group #2: Control Temperature Source 0 = Return 1 = Space Temperature Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Setpoint Pressures in 0.02 IWC increments from 0 to 200 * 0.02 = 4.00 IWC Group #3: Control Temperature Source 0 = Return 1 = Space Temperature Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Setpoint Pressures in 0.02 IWC increments from 0 to 200 * 0.02 = 4.00 IWC 0-1 0-2 0-2 0-200 0-1 0-2 0-2 0-200 0-1 0-2 0-2 0-200 0917 0918 091B 091A 091D 091E 0921 0920 0923 0924 0927 0926 Rooftop/RMC Open Protocol Data Communications 4.1

Variable Name Limits Address Group #4: Control Temperature Source 0 = Return 1 = Space Temperature Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Calculation 0 = Minimum 1 = Maximum 2 = Average Pressure Setpoint Pressures in 0.02 IWC increments from 0 to 200 * 0.02 = 4.00 IWC Group Number Assignment Unit #1 Unit #2 Unit #3 Unit #4 Unit #5 Unit #6 Unit #7 Unit #8 0-1 0-2 0-2 0-200 0-4 0-4 0-4 0-4 0-4 0-4 0-4 0-4 0929 092A 092D 092C 082D 082E 082F 0830 0831 0832 0833 0834 Number of Rooftop Units 1-8 0900 Group #? Control Temperature Source Group #1 $0917 Group #2 $091D Group #3 $0923 Group #4 $0929 The Group #? Control Temperature determines what parameter the group will use to determine if it is in a cool or heat mode. See Network Control Features for more information. Group #? Temperature Calculation Group #1 $0918 Group #2 $091E Group #3 $0924 Group #4 $092A The RMC will calculate a Group Control Temperature based on the Group #? Temperature Calculation. For example, if the Group #? Temperature Calculation is set to Minimum, the RMC will use the minimum temperature (return or space) of all rooftops in that specific group. See Network Control Features for more information. Group #? Pressure Calculation Group #1 $091B Group #2 $0921 Group #3 $0927 Group #4 $092D 42 Rooftop/RMC Open Protocol Data Communications 4.1

The RMC will calculate a Group Static Pressure based on the Group #? Pressure Calculation. For example, if the Group #? Pressure Calculation is set to Minimum, the RMC will use the minimum duct static pressure of all rooftops in that specific group. See Network Control Features for more information. Group #? Pressure Setpoint Group #1 $091A Group #2 $0920 Group #3 $0926 Group #4 $092C The Group #? Pressure Setpoint is used to control the static pressure in the duct. Multiply this value by 0.02 to obtain a value in IWC. See Network Control Features for more information. Group Number Assignment Unit #1 $082D Unit #2 $082E Unit #3 $082F Unit #4 $0830 Unit #5 $0831 Unit #6 $0832 Unit #7 $0833 Unit #8 $0834 The Group Number Assignment will allow the BAS to assign a rooftop to a group. Rooftop units set to the same group will operate together according to other setup parameters. See Network Control Features for more information. Rooftop/RMC Open Protocol Data Communications 4.1

Applied Rooftop Simulator Package Purpose Development Tools Monitor Installation 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. McQuay International offers the following tools to facilitate the development and testing of an Open Protocol interface for Applied Rooftop units. Literature: McQuay "Open Protocol Data Communications - Data Packet Protocol" document (version 4.1 dated March, 1999 or latest update). Hardware required: McQuay offers the following hardware for rooftop development: Model 250 controller(s) RS-232 Communications Cable package RS-485 Communication Cable package McQuay Open Protocol Monitor and Simulator software for Applied Rooftop. The Microsoft Windows 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. 44 Rooftop/RMC Open Protocol Data Communications 4.1

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. Rooftop/RMC Open Protocol Data Communications 4.1

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 user name: MCQUAY password: PARTNER. 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: 46 Rooftop/RMC Open Protocol Data Communications 4.1

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: 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 Rooftop/RMC Open Protocol Data Communications 4.1

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: 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: 48 Rooftop/RMC Open Protocol Data Communications 4.1

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 Rooftop/RMC Open Protocol Data Communications 4.1

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). 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. 50 Rooftop/RMC Open Protocol Data Communications 4.1