Faults:

HPA faults are relay contact inputs. There are 2 types of HPA fault inputs for each amplifier. 

Each Amplifier has a Normally Open fault input (a closure represents a fault), and a Normally Closed fault input (an open represents a fault).  One or both may be used.  If the Normally closed fault input is not used, then it is necessary to place a permanent short across the fault input pins.

 A fault is latched.

In the event of a fault, the HPA BI-colored led turns from green to a flashing red.  The audible alarm sounds (if enabled) on and off.  The only way to turn off the alarm is to push the RESET button.  If the fault no longer exists, then the HPA led will go from a flashing red to green.  If the fault still exists, the HPA led will remain on steady red until the fault has been corrected.

A fault will cause the “Summary Fault” indicator relay (which is on the REMOTE STD port of the controller) to close upon a fault.  This relay will remain closed until a reset has been entered.  The fault must be “acknowledged” in order for this relay to reset itself.  In other words, any fault will cause it to close, and only a front panel reset will reset it.

Each amplifier has its own fault indicator on the REMOTE STD port.  These fault indicator track the existing fault condition.  If a fault exists, the relay is closed.  If there is no fault, the relay indicator is open.