69 of 222 pages
Operating and service manual
108
Tsup 2 invalid
Warning
Description
Supply Air Temperature Sensor 2 Invalid
Cause
Indication of defective supply air temperature sensor or its measuring circuitry
or sensor not mounted correctly in unit
Trouble
shooting
Possible causes:
•
Active alarms AL 106, AL 107 or AL 901
•
Temperature sensor reading is out of valid range:
-60°C (-76°F) or above +140°C (284°F).
•
Difference between Tsup1 and Tsup2 is larger than 1°C:
1°C difference for more than 30 min. or up to 10°C difference in more
than 3 min.
Accompanied alarms:
•
AL 106 or AL 107 may also be active.
Trouble shooting:
1) If alarms AL 106 or AL 107 are active, check their trouble shooting
section first.
2) Check that both sensors, Tsup1 and Tsup2 are mounted correct by their
mounting holes.
3) If AL 901 is active, see trouble shooting for AL 901
4) 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.
5) Measure the resistance between the two wires.
a) If the resistance is out of range of the resistance and temperature table,
Tables
starting p.204, the temperature sensor and cable are defect and
should be replaced.
b) If the resistance is within range, perform controller door check
Trouble
shooting for Star Cool Controller
p.56 before replacing controller
door.
Criteria
Value is below alarm limit -60°C (-76°F) or above +140°C (284°F) or difference between
Tsup1 and Tsup2 is more than
(>)
1°C for 30 min. or up to 10°C difference.
Value invalid for 30 sec. for alarm activation.
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. Value must be valid for 60 sec. to set alarm inactive.
Log data
Parm 1
Parm 2
Parm 3
Parm 4
Parm 5
Active/Inactive