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Event Message Help Text
CB1 SHUNT TRIP FAIL
Circuit Breaker 1 Shunt Trip Failure
Circuit Breaker 1 failed to trip open when the control issued a command for the circuit breaker to trip.
Press SILENCE on the touch screen to turn off the audible alarm, if so configured. If you are accessing the STS2 system from a terminal, type SH and press RETURN on your keyboard to turn off the audible alarm.
Contact Liebert for technical support at
This event was written to the Event Log, if so configured.
The alarm has triggered a message to be sent to the modem, if so configured.
If configured to be a latching alarm, press RESET on the display. If you are accessing the unit from a terminal, type CA and press RETURN on your keyboard.
CB2 SHUNT TRIP FAIL
Circuit Breaker 2 Shunt Trip Failure
Circuit Breaker 2 failed to trip open when the control issued a command for the circuit breaker to trip.
Press SILENCE on the touch screen to turn off the audible alarm, if so configured. If you are accessing the STS2 system from a terminal, type SH and press RETURN on your keyboard to turn off the audible alarm.
Contact Liebert for technical support at
This event was written to the Event Log, if so configured.
The alarm has triggered a message to be sent to the modem, if so configured.
If configured to be a latching alarm, press RESET on the display. If you are accessing the unit from a terminal, type CA and press RETURN on your keyboard.
HEAT SINK OVERTEMP
Heat Sink Over Temperature
The system heat sink temperature has exceeded the design limits.
Take immediate steps to cool the unit. Remove obstructions from the air inlet in the front of the unit. Remove and replace the air filter behind the front door. A standard furnace filter can be used.
Press SILENCE on the touch screen to turn off the audible alarm, if so configured. If you are accessing the STS2 system from a terminal, type SH and press RETURN on your keyboard to turn off the audible alarm.
This event was written to the Event Log, if so configured.
The alarm has triggered a message to be sent to the modem, if so configured.
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