System Temperature Sensor(S) - Northern Telecom DMS-100 Series Maintenance Manual

System temperature sensor(s)

The system temperature
These sensors provide an early warning alarm indicating that the DPP is
exceeding its recommended operating temperature. To test the external
temperature alarm circuitry at the J16 connector on the input connector
panel, short pins 7 and 8 together. Alarms are shown by the "CONV FAIL"
lamp on the Frame Supervisory Panel (FSP) and the Office Alarm, if
equipped.
Testing temperature alarms
To test the external temperature alarm circuitry at the J16 connector on the
input connector panel, short pins 7 and 8 together. Alarms are shown by the
"CONV FAIL" lamp on the Frame Supervisory Panel (FSP) and the Office
Alarm, if equipped.
The DPP temperature alarm will activate given any of the following
conditions:
•
•
•
After the temperature alarm is set, reduce the ambient temperature measured
at the fan filter inputs on the rear of the DPP chassis inside the equipment
bay to 80
cabinet doors can speed the thermostat reset by allowing better air
circulation.
Note: Test each chassis separately.
the external ambient temperature measured at the fan filter inputs on the
rear of the DPP chassis inside the equipment bay exceeds 100
any fan fails and the ambient temperature measured at the fan filter
inputs on the rear of the DPP chassis inside the equipment bay
o
approaches 100 F, or
the fan filters become clogged blocking cooling air through the interior
of the DPP.
CAUTION
Continuous operation of the DPP under extreme heat conditions
will degrade system operation.
o
F to reset the thermostat. Removing the DPP front covers and rear
DPP Recovery and Routine Maintenance Guide BCS35 and up
s
ensors are located inside the power supplies.
Routine maintenance 7-5
o
F, or