Unmet Hours

EMS program – AirTeminal:SingleDuct:UserDefined and ZoneAmbient

Have any of you used the “AirTerminal:SingleDuct:UserDefined” object before?

I need to use it as part of an EMS program and in particular the actuator called “Component Zone Internal Gain”. However, every time I set “Ambien Zone Name” in the “AirTerminal:SingleDuct:UserDefined” object, the simulation crashes (no err file is created).

Since I am not really experienced with EMS, I looked at the example file called “EMSUserDefined5ZoneAirCooled”. In this model, the “Ambient Zone Name” field of the “AirTerminal:SingleDuct:UserDefined” object is not set. I tried to set it to any of the zones and each time the simulation has crashed without creating an err file, just like in my model.

What am I missing?

I ran such a test in a debug build and caught the crash in the debugger and there is a programming mistake causing the crash. There isn't anything you are doing wrong and nothing can be done with input to fix it. I will file a bug report.

Those sorts of ancillary internal gains are pretty special. That zone name isn't needed for the normal operation of an air terminal as it will condition the zone by the passing air into it, not by internal gains. None of the regular air terminals have such modeling capabilities. The node connections and air distribution unit object already tell the program which zone the terminal is connected to.

As a work around, if you really need to model some special case of ancillary gains, you could use OtherEquipment and actuate the schedule to control the heat gains.