Section 7: Troubleshooting; Introduction - Eaton MDN-408 Instructions For Installation, Operation And Maintenance

SECTION 7: TROUBLESHOOTING

7-1 INTRODUCTION

Table 7.1 will help to determine the probable causes of
simple circuit breaker problems and possible corrective
actions. Possible problems associated with the elec-
tronic trip unit are covered in companion publications,
I.L. 70C1037H04 and I.L. 70C1036H05. If the problem
cannot be resolved with the aid of one or both of these
guides, contact the Cutler-Hammer service center for
more in-depth assistance.
Table 7.1 Circuit Breaker Troubleshooting Guide (continued on next page)
Symptom
The circuit breaker trips open
(red fault trip indicator button
is out and/or fault indicator LED
is lighted) when closed on a
load current
Circuit breaker opens
(fault trip indicator button
is not out)
I.B. 2C12060H08
Probable Cause
Rating plug not installed
and load current through
the breaker
Repeated closing on
transient (in-rush) current
with thermal memory active
An overload or fault current
condition
Undervoltage release
operates; voltage too low
or zero
Shunt trip operates
Trip latch is defective
For more information visit: www.EatonElectrical.com
Instruction Book
Effective: May 2006
Corrective Actions
Install rating plug that
corresponds to current sensors
Wait for circuit breaker (and
loads) to cool before re-closing
Use status and fault
indicators to help locate and
remove overload or fault
condition
Check and correct the UVR
supply voltage (85-110% rated
voltage)
Check control signal(s) to
shunt trip; correct if necessary
Inspect latch condition and
engagement before closing;
consult Cutler-Hammer service
center
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