Technical information

PLC C
ONTROL
ALARM
CONDITIONS
Alarm
Fan Overload alarm
Possible cause
Access door is open.
Overload switch has been
manually shut off.
Overload set incorrectly.
Low supply voltage.
Faulty contactor
Faulty overload module.
Control voltage is incor-
rect.
Solution
Close access door.
Reset overload switch.
Check table on wiring diagram for
correct full load amperage (FLA)
draw. Adjust overload accordingly.
o Check supply voltage. Supply
voltage to contactor should be +-
10% of nameplate voltage.
o Check wire terminations and
connections. Tighten if loose.
Check line and load side of contac-
tor. It should be less than 5 volt drop
across the contactor. If it is not,
replace the contactor. See Replacing
the Contactor in the Troubleshooting
section.
Check amp draw of circuit. If it is
under the rated setting, replace the
overload module. See Replacing
Overload Modules, in the
Troubleshooting section.
Check 24VDC required for contac-
tor auxiliary input. If control voltage
is OK replace PLC.
UGH024/1103 Portable Chillers
TROUBLESHOOTING
6-45