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Effective 8/2006
Page 30
I.L. 66A7534H04
Symptom
Probable Cause
Possible Solution(s)
References
Current through breaker is
<25% of sensor rating
No problem. Status LED will
not operate with breaker
currents <25% of sensor
rating
Unit status LED is not blinking
Trip unit is malfunctioning
Replace trip unit
Light loading
No problem. Unit Status LED
will not flash until 25% of
sensor rating
See Note in Section 3.2
Unit Status LED is steady on
Trip unit is malfunctioning.
Replace trip unit
Rating plug is not installed or
is loose
Install rating plug and/or
check for loose connections
Rating plug is open internally
Replace rating plug
As soon as current starts to
flow through the breaker, it
trips and the Instantaneous
trip LED comes on
Trip unit is malfunctioning
Replace trip unit.
Battery installed backwards
Install correctly
Dead battery
Replace battery
LED does not come on when
battery check button is
pressed
Trip unit is malfunctioning
Replace trip unit
There actually is a ground
fault
Find location of the fault
CH Type-V current sensors in
one or more phases have
incorrect polarity
Verify circuit breaker wiring
Refer to Appendix C
Trip unit is malfunctioning
Replace trip unit
Breaker trips on ground fault
High inrush phase currents
may cause fictitious ground
pickup momentarily
Connect Zout to Zin jumper to
provide some time delay
See Caution in Section 3.3
Connection from Zout to Zin is
missing
Make connections B8 to B9
Refer to Appendix A
Trip unit settings are not
correct
Change settings
Breaker trips too rapidly on
ground fault or short delay
(Zone Selective Interlocking
not used)
Trip unit is malfunctioning
Replace trip unit.
Long Time Memory selected
Turn off Long Time Memory
Refer to Section 4.3
Breaker trips too rapidly on
long delay
Trip unit settings are not
correct
Change settings. Long Time
Delay setting is based on 6
×
Ir
Appendix B Troubleshooting Guide