Orion System PREHEAT-X - Manual (Page 9)

PREHEAT-X Technical Guide
OPERATION MODES
9
Outputs and Operation Modes
Operation Modes
The PREHEAT-X Controller can be used stand-alone or communicat-
ing with an AAON Unit Controller using a modular cable.
Stand-Alone Mode
When used in a stand-alone application, the PREHEAT-X Controller
will modulate SCR or SSR Heat and stage any additional fi xed stages
to maintain the Leaving Air Temperature setpoint confi gured on the
PREHEAT-X Controller LCD display. The PREHEAT-X Controller
is activated by a 24VAC signal to the HEAT EN input.
Communicating Mode
When the PREHEAT-X Controller is connected and communicating
with an AAON Unit Controller via a modular cable, the necessary
information will be passed between the PREHEAT-X and the Main
Unit Controller to properly operate in the Heating Mode.
If the communication is interrupted between the PREHEAT-X
Controller and the Main Controller, both boards will show an alarm
and the PREHEAT-X outputs will turn off. When communication is
restored, the alarms will go away.
In this confi guration, the Leaving Air Temperature Setpoints and the
Preheat Enable Sepoints are set using the Main Controller.