PIR Ready VT76xx Series Programmable & Non-Programmable Thermostats For Commercial HVAC Applications BACnet Integration Manual September 1, 2010 1
Product Overview The VT76xx PI thermostat family is specifically designed for single stage and multi-stage control of heating/cooling equipment such as rooftop and selfcontained units. The product features an intuitive, menu-driven, back-lit LCD display, which walks users through the programming steps, making the process extremely simple.
VT7600 series Protocol Implementation Conformance Statement (PICS) Vendor Name: Vykon Vendor ID: 140 Product Name: VT7600 Thermostat Series Product Model Number: VT7600A5X28B, VT7600B5X28B, VT7605B5X28B, VT7607B5X28B, VT7600H5X28B, VT7652A5X28B, VT7652B5X28B, VT7656B5X28B, VT7657B5X28B and VT7652H5X28B. Product Description: The VT76xx series BACnet communicating thermostat have been specifically designed for RTU and heatpump applications to be monitored on a BACnet MS-TP® network.
Device Object Table Object Name VT76xxX5x28B Type and Instance Device Object Property Object_Identifier Thermostat Parameter Unique ID number of a device on a network Property 75 (R,W) Object_Name Unique name of a Device on a network Property 77 (R,W) Model Name Thermostat Model number Property 70 (R) Firmware Revision Current BACnet firmware revision used by the thermostat Property 44 (R) Protocol Version Current BACnet firmware protocol version Property 98 (R) Default is Version 1 Protocol
VT7600A5x28B VT7652A5x28B VT7600B5x28B VT7652B5x28B VT7605B5x28B VT7656B5x28B VT7607B5x28B VT7657B5x28B VT7600H5x28B VT7652H5x28B Objects Table Room Temperature AV 7 Present_Value (R,W) √ √ √ √ √ √ √ √ √ √ Room Temp Override BV 8 Present_Value (R,W) √ √ √ √ √ √ √ √ √ √ Outdoor Temperature AV 9 Present_Value (R,W) √ √ √ √ √ √ √ √ √ √ Outdoor Temp Override BV 10 Present_Value (R,W) √ √ √ √ √ √ √ √ √ √ Room Humidity AV 11 Present_Value (R) √ √
VT7600A5x28B VT7652A5x28B VT7600B5x28B VT7652B5x28B VT7605B5x28B VT7656B5x28B VT7607B5x28B VT7657B5x28B VT7600H5x28B VT7652H5x28B Controller Status GRP 23 Present_Value (R) √ √ √ √ √ √ √ √ √ √ AUX BI 24 Present_Value (R) √ √ √ √ √ √ √ √ √ √ G Fan BI 25 Present_Value (R) √ √ √ √ √ √ √ √ √ √ Y1 Cool BI 26 Present_Value (R) √ √ √ √ √ √ √ √ √ √ Y2 Cool BI 27 Present_Value (R) √ √ √ √ √ √ √ √ W1 Heat BI 28 Present_Value (R) √ √ √ √ √
VT7600A5x28B VT7652A5x28B VT7600B5x28B VT7652B5x28B VT7605B5x28B VT7656B5x28B VT7607B5x28B VT7657B5x28B VT7600H5x28B VT7652H5x28B General Options 1- GRP 46 Present_Value (R) √ √ √ √ √ √ √ √ √ √ Temperature Scale BV 47 Present_Value (R,W) √ √ √ √ √ √ √ √ √ √ Heating Setpoint Limit AV 48 Present_Value (R,W) √ √ √ √ √ √ √ √ √ √ Cooling Setpoint Limit AV 49 Present_Value (R,W) √ √ √ √ √ √ √ √ √ √ Heating Lockout Temperature AV 50 Present_Value (R,W
VT7652H5x28B VT7600H5x28B VT7657B5x28B VT7607B5x28B VT7656B5x28B VT7605B5x28B VT7652B5x28B VT7600B5x28B Object Property VT7652A5x28B Type and Instance VT7600A5x28B Object Name Programmable Model Configuration Options GRP 69 Present_Value (R) √ √ √ √ √ Progressive Recovery BV 70 Present_Value (R,W) √ √ √ √ √ Event Display MV 71 Present_Value (R,W) √ √ √ √ √ Stages Configuration Options GRP 72 Present_Value (R) √ √ √ √ √ √ Heating Stages MV 73 Present_Value (R,W
BV 88 Present_Value (R,W) √ √ Dehumidification RH Setpoint AV 89 Present_Value (R,W) √ √ Dehumidification Hysterisys AV 90 Present_Value (R,W) √ √ Dehumidification Low OA Lockout AV 91 Present_Value (R,W) √ √ Dehumidification Lockout Functions BV 92 Present_Value (R,W) √ √ Dehumidification Output Status BI 93 Present_Value (R) √ √ Humidification Model Configuration Options GRP 94 Present_Value (R) √ √ Humidification RH Setpoint AV 95 Present_Value (R,W) √ √ Eff (Effect
Standard Object Types Supported Object Type Supported Objects Dynamically Creatable Dynamically Deletable Optional Properties Supported Writable Properties ; Reliability Out_of_Service Reliability Present_Valuea Out_of_Servicea Object_Nameb Analog Input Analog Value ; Binary Input ; Binary Value ; Device ; Max_Master Max_Info_frames Object_Identifier Object_name Max_Master Group ; N/A N/A Multi-state Value ; Reliability States_Text Sched
List of Property Value Range Restrictions for AI and AV objects Object Type and instance Under range value Over range value Default value Room Temperature AV 7 -40°F (-40°C) 122°F (50°C) N/A Outdoor Temperature AV 9 -40°F (-40°C) 122°F (50°C) N/A Room Humidity AV 11 0% 100% N/A Supply Temp AI 16 -40°F (-40°C) 122°F (50°C) N/A Supply RH AV 17 0% 100% N/A PI Heating Demand AV 20 0% 100% N/A PI Cooling Demand AV 21 0% 100% N/A Economizer Output AV 22 0% 100% N/A Occu
List of Property Enumeration Sets for BI and BV objects Object Name Object Type and instance Inactive_Text Default value Active_Text Room Temp Override BV 8 Normal Override Normal Outdoor Temp Override BV 10 Normal Override Normal AUX BI 24 Off On Off G Fan BI 25 Off On Off Y1 Cool BI 26 Off On Off Y2 Cool BI 27 Off On Off W1 Heat BI 28 Off On Off W2 Heat BI 29 Off On Off Reversing Valve BI 30 Off On Off DI 1 Status BI 31 Not Activated Activated Not Acti
List of Property Enumeration Sets for MV Objects Object Name Object Type and instance Occupancy Command MV12 System Mode HPU MV13 System Mode RTU MV14 Fan Mode MV15 Keypad Lockout MV18 Effective Occupancy MV 34 Heating CPH MV53 Cooling CPH MV54 Temporary Occupancy Time MV61 BACnet Index Text 1 2 3 1 2 3 4 5 1 2 3 4 1 2 3 1 2 3 1 2 3 Local Occupancy Occupied Unoccupied Off Auto Cool Heat Emergency Off Auto Cool Heat On Auto Smart Level 0 Level 1 Level 2 Occupied Unoccupied Temporary O
Object Name Object Type and instance Anticycle MV63 DI1 Configuration MV65 DI2 Configuration MV66 Proportional Band MV 67 Event Display MV71 Heating Stages MV73 Cooling Stages MV74 Heat Pump Stages MV75 BACnet Index Text 1 2 3 4 5 6 1 2 3 4 5 6 1 2 3 4 5 6 1 2 3 4 5 6 7 0 minute 1 minute 2 minutes 3 minutes 4 minutes 5 minutes None RemNSB RemOVR Filter Service Fan lock None RemNSB RemOVR Filter Service Fan lock 2 2F 3 3F 4 4F 5 5F 6 6F 7 7F 8 8F 1 2 1 2 1 2 1 2 2 Events 4 Events 1 Sta
Integration – Global Commands The following figure shows which objects from the thermostat can be monitored and commanded from the BAS front-end.
Integration – Typical Graphic User Interface (GUI) Objects The following objects should be typically used in a GUI: ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ Room Temperature (AV7); Occupied and Unoccupied Heat Setpoints (AV 42 and AV44); Occupied and Unoccupied Cool Setpoints (AV 43 and AV45); Outdoor Temperature (AV9); Supply Temperature (AI16) (If available); Occupancy Command (MV12); Effective Occupancy (MV34); System Mode RTU (MV14) or System Mode HPU (MV13); G Fan (BI25); Y1 Cool (BI26); Y2 Cool (BI2
Configuration Objects The following objects and group objects should be typically used for configuration purposes: ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ General Options 1 Group GRP 46 and its complete list of objects; General Options 2 Group GRP 58 and its complete list of objects; Programmable Model Configuration Options Group GRP 69 and its complete list of objects; Stages Configuration Options Group GRP 72 and its complete list of objects; Economizer Model Configuration Option Group GRP 76 and its complete list of objects; H
Cable Type Vykon recommends the use of balanced 22-24 AWG twisted pair with a characteristic impedance of 100-130 ohms, capacitance of 30 pF/ft or lower. A braided shield is also recommended. Impedance A value based on the inherent conductance, resistance, capacitance and inductance that represent the impedance of an infinitely long cable. The nominal impedance of the cable should be between 100Ωand 120Ω. However using120Ω will result in a lighter load on the network.
Maximum Number of Devices A maximum of 64 nodes is allowed on a single daisy chain segment. A node is defined as any device (Panel, Zone, Repeater, etc) connected to the RS485 network. Terminators do not count as a node. To determine the number of nodes on a network, add the following: ¾ ¾ One node for each device, including main panels One node for each repeater on the chain For the example in Figure 4, we have one node for the main Panel, plus 4 for the controllers, for a total of 5 nodes.
Figure 5: Correct usage – repeaters are daisy chained to the supervisory controller and separate daisy chains branch from each repeater. Do not install repeaters in series, as this may result in network reliability problems. Figure 6 demonstrates an incorrect use of a repeater in an EIA-485 network.
End Of Line (EOL) Resistors MS/TP network must be properly terminated. For daisy chain configurations, you must install an EOL resistor at each end of the daisy chain. Depending on your MSTP network configuration, the resistance value of the EOL resistor may change: • Vykon’ devices are installed at both ends of the MSTP network: 120 Ohms resistor should be installed at each end.
Table 2 shows the different possibilities with the Status LED behaviour of the BACnet module.
Integrating Vykon’ Devices on an MSTP Network Before doing any BACnet integration, make sure to have Vykon’ PICS (Protocol Implementation Conformance Statement). Vykon’ devices do not support the COV service. COV reporting allows an object to send out notices when its Present-Value property is incremented by a pre-defined value.
Tips and Things You Need To Know ¾ Each thermostat is delivered from the factory with the default MAC address set at 254. At this value, the BACnet communication is NOT active and the device will not participate in the token pass either. The local LED status for the communication adapter at this point is one short flash only. To enable the BACnet communication, set the local MAC address configuration property of the thermostat to any valid value from 0 to 127.
Troubleshooting Section Error / Trouble Condition Thermostat does not come online Possible Cause Solution Two or more controllers have the same MAC address. The MS/TP network has too many devices. Too many devices were installed without any repeaters. The MS/TP cable runs are broken Modify each duplicate address to a unique number. Do not exceed the maximum number of devices and maximum length allowed by the EIA-485 specifications. Repeaters need to be installed as specified in this document.
