Operating and service manual
68 of 222 pages
107
Tsup 2 short
Warning
Description
Supply Air Temperature Sensor 2 Short Circuit
Cause
Indication of short-circuited supply air temperature sensor
Trouble
shooting
Possible causes:
•
Temperature sensor Tsup2 or its cable defective.
•
X1 cable is defect.
•
Controller PCB defective.
Accompanied alarms:
•
AL 108.
Trouble shooting:
1) Disconnect the sensor cable for sensor Tsup2 from the connector on the
interface/terminal block PCB, according to the wiring schematics inside in
the control cabinet.
2) Measure the resistance between the two wires.
a) If the resistance is less than (<) 230 Ω, the cable or the sensor is defect,
replace sensor and cable.
b) If the resistance matches the resistance and temperature in table,
Tables
starting p.204, the temperature sensor and cable are ok.
3) Measure the voltage over the connector for Tsup2. It should be between
4.80 and 5.05V DC
a) If the voltage is inside the above range, connect sensor again. Measure the
voltage over the sensor and check voltage/temperature according to
Tables
starting p.204
b) If the voltage is outside the above range, the controller PCB is defect or
other sensors may be defect and pulling the voltage down. Check other
alarms and see
Trouble shooting for Star Cool Controller
p.56 before
replacing controller door.
Criteria
Value above high alarm limit +140°C (284°F)
Controller
action
Replacement by new value from AAS system
Log
X
Alarm
X
Alarm light
Off
Consequence
Deteriorated control precision in the
chill
mode.
Elimination
When sensor value becomes valid, it is marked as inactive in the alarm list and may then
be deleted.
Log data
Parm 1
Parm 2
Parm 3
Parm 4
Parm 5
Active/Inactive Low limit
High limit
Present
