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6.3 COMMON ALARMS—WHAT TO LOOK FOR
The CM 2000 and the CM 2000+ control modules have a wide range of alarming features that may be selectively enabled or disabled
to allow the monitoring and indication of trouble conditions. Described below are the different alarm conditions available on the
control module, their meanings, and possible causes.
Alarm Description Cause of Alarm
Switch
Limiting
This alarm indicates that the control module is
limiting the average current that is applied to the
heating circuit based on the SWITCH RATING
setting to protect the solid-state relay from excess
current.
• SWITCH RATING setting is lower than actual current rating
of SSR
• High in-rush current from “cold start” of self-regulating cable
• Damaged or partially shorted heating cable
• “As built” cable length is greater than design value
• Incorrect CURRENT TURNS RATIO setting
• Incorrect wiring
Contactor
Count (CM
2000+ Only)
This alarm indicates that the number of off-to-
on transitions of a contactor has exceeded the
CONTACTOR COUNT ALARM setting and the
contactor should be replaced.
• Alarm setting is incorrect
• Contactor has been controlling the heating circuit for a long
time
• Some configuration parameter (i.e. DEADBAND, AUTO-CYCLE
INTERVAL, load shedding etc.) is causing the contactor to
toggle more than usual.
EEROM Data
Failure
This alarm indicates that the control module has
detected a failure in its non-volatile memory. This
indicates an internal problem and the control
module should be replaced and returned to the
factory for repair.
• The control module cannot bypass the failed area of its
memory and has loaded factory defaults into this failed area.
IMPORTANT: This alarm cannot be reset.
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