Issue
Instructions and programming example for using nviEmergCmd to control the damper on the Xenta 102-AX
Environment
- Xenta 102-AX
- Menta
Cause
In some situations it is necessary to have the Xenta 102-AX damper open to 100% for smoke control, or other sequence of operations specific tasks. There are different emergency modes which all perform a different function.
Resolution
The damper position on the 102-AX can be controlled to 100% or to 0% by using the SNVT input nviEmergCmd. Please see the attached Menta file as a programming example.
The enumeration breakdown and controller actions of nviEmergCmd are as follows:
0 = Emerg Normal - Normal operation of the controller without any emergency command.
1 = EmergPressurize - 102-AX will control to its max cooling CFM setpoint.
2 = EmergDepressurize - 102-AX will control its damper to 0% and shut off all other outputs.
3 = EmergPurge - 102-AX will control the damper to 100%
4 = EmergShutdown - 102-AX will pause control on the damper and disable all other outputs.
5 = EmergNull - Null SNVT value
NOTE: Any value change on nviEmergCmd will initiate a damper resynchronization. This will cause the controller to fully close its damper, fully close any floating control outputs, and disable any other hardwired outputs for their full stroke time (throttling range).