Supply air VAV changeover condition is an indicator of air source heating\cooling status from Air Handling Unit. When there is heating or cooling request from room, in order for the DXR1s to know heating\cooling status of air source to apply different control behaviors in control loop, users must manually synchronize the value of object Supply air VAV changeover condition with that of the corresponding object in AHU.
- Object information
- Object name = %RSegm%'HVAC'VavSu'VavSuChovrCnd
- Object description = Supply air VAV changeover condition
- Object type = Multistate value
- State text = [1=Neither|2=Heating|3=Cooling|4=Neutral]
- "Neutral" means that heating and cooling PID controllers are both enabled and that the system is providing air that is not hot or cold.
- Object ID: Refer to document A6V14039451.
- Coordinate way 1# - Central functions
- If a Siemens controller is installed in building automation system for central function purpose, DXR1s can be assigned to this Siemens Controller-Central function as group members, then DXR1s can be managed by Siemens Controller-Central function by one step operating.
- Central function in the following devices:
- DXR2.x18 – supported by released application type library.
- PXC4/5/7 serial - needs to be programmed by customer based on PXC’s library.
- Note: For more details of engineering steps shown in the above screenshot, see corresponding engineering documents of supported controllers.
- Coordinate way 2# - Manual management from BMS
- Modify present value of object Supply air VAV changeover condition in each DXR1 in the loop to the current heating\cooling state.