GEI-50299
Power Circuit Breakers Types
AK-2-15
and
AK-2/3-25
TROUBLES HOOTING
ALL E XCESS LUBRICANT S HOULD BE REMOVED
WITH A CLEAN CLOT H
IN
ORDER TO A V OID
ANY ACCUMULATION OF DIRT OR DUST.
At each maintenance period, all s ilver to
s ilver friction points, such as primar ydisconnects,
should be cleaned and g iven a fresh coat of G. E .
Spec. No. D50H4 7 lubr icant.
The following table l ists several typ ical s ymp
toms of breaker malfunct ion, together with the ir
causes and remedies.
If, at any tim e, these
s ymptoms are observed, the ir cause should be
determined and the necessar y corrective action
should be taken.
TROUBLE
CAUSE
REMEDY
Overheating
Contacts not aligned
Adjust contacts.
AK-2/3 Breakers
Contacts dirty, greasy or coated with dark
film
Clean contacts
Contacts badly burned or pitted
Replace contacts
Current carrying surfaces dirty
Clean surfaces
of
current carrying parts
Corrosive atmosphere
Relocate or provide adequate enclosure
Insufficient bus or cable capacity
Increase capacity
of bus
or cable
Bolts and nuts at terminal connections
Tighten, but do not exceed elastic limit
of
not tight
bolts or fittings.
Current in excess
of
breaker rating
Check breaker application or modify circuit
by decreasing load
Excessive ambient temperature
Provide adequate ventilation
Failure to trip
Travel of tripping device does not provide
Re-adjust or replace tripping device and
AK-2 Breakers
positive release
of
tripping latch
check mechanism latch adjustment
Worn or damaged trip unit parts
Replace trip unit
Bind in overcurrent trip device
Replace overcurrent trip device
False Tripping
Overcurrent trip device pick up too low
Check application
of
overcurrent trip device
AK-2 Breakers
Overcurrent trip device time setting too short Check application
of
overcurrent trip device
Bind in overcurrent trip device
Replace overcurrent trip device
Failure to Close and Latch
Bin
�
in attachments preventing resetting
Re-align and adjust attachments
AK-2/3 BreaKers
of
late
Latch out
of
adjustment
Adjust latch
Latch return spring too weak or broken
Replace spring
Hardened or gummy lubricant
Clean bearing and latch surfaces
Closing solenoid burned out
Replace solenoid coil
Solenoid control device not functioning
Re-adjust or replace device
properly
False Tripping
Captive Thump screw on Power Sensor
AK-3 Breakers
loose fail-safe circuitry reverts
Tighten thumb screw on desired setting
characteristic
to
minimum setting and
maximum time delay
Tap setting dial on Power Supply incorrectly
Set
dial to
correspond with Power Sensor coil
set
tap
External Ground Sensor Coil improperly
Refer
to
Figure 22, page 29 for polarity and
connections. Check continuity of shield and
connected
conductors connecting the external Ground
Sensor coil.
Failure to Trip
Loose or disconnected power sensor dis-
Tighten or reconnect disconnect plugs
AK-3 Breakers
connect plugs
Loose or broken power sensor coil tap
Tighten or reconnect tap connections
connections
6
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