Power Supply; Power Sensor Unit; Magnetic Trip Device - GE AK-2A-15 User Maintenance Manual

GEI-50299 Power Circuit Breakers Types AK-2 -15
NOTE : No adjustment to the taps controlling
pick-up or timing should be made with the breaker
carrying current.
In the event the Power Sensor Device must
be made non-operative to allow the breaker
to continue carrying current without over­
current protection, it is recommended that
the leads to the tripping solenoid be removed
to completely eliminate the possibility of the
breaker tripping.
power on the main contacts while the dis­
connect plug to the magnetic coils is dis­
connected
1 . Check for the existence of overcurrent or
ground fault conditions that may be causing
Fig. 1 5 . (8039850) Power Supply
1 .
Rating Disc
2 . Mounting Bracket
3 . Male Disconnect Plug
Figure 1 6 . (804 1 8 64) Power Sensor Unit
1 . Mounting Screw
2 . Captive Thumb Screw
3 . Name Plate
2 6
Do not close breaker with
4 .
Female Disconnect Plug
5 . Terminal Block
6 . Mounting Bracket
and
AK-2/3-25
the breaker to trip as a proper response to
these abnormal circuit conditions.
2. The possibility of the breaker being trip
free by mechanical interferences along the
trip shaft or inadvertent shunt trip opera­
tions should be positively eliminated before
investigating the Power Sensor.
operations in the test position should be ob­
tained before proceeding with the Power Sensor
trouble shooting.
3 . A PST-1 Power Sensor Test Kit must be
available. (Figure 2 1 ) .
Sensor Unit for correct function for each
pick-up setting and one point on each time
delay characteristic.
correct operation of each phase of the Power
Supply Unit.
the instruction manual (GEK-7301 ) for the
PST- 1 Test Kit, and GEK- 7309 Power Sensor
Instructions.
test do not deviate more than 1 0% from the
published curves, proceed to step 4 .
deviation is more than 1 0% contact the factory
for possible replacement of the Power Sensor
Unit.
4 . If the breaker is equipped with ground fault
protection, determine whether the false trip­
ping is the result of falsely answering an
overcurrent trip or a ground trip signal. This
may be determined by temporarily eliminating
the ground trip signal by shorting out the
ground signal points 1 and 5 at the ground
signal terminal board on the back frame bottom
of the breaker.
identified by the 0. 1 5UF capacitor connected
Figure 1 7 . (804 1 8 63 ) Magnetic Trip Device
1 . Name Plate
2 . Mounting B racket
3. Spring
4 . Trip Arm
5. Adjusting Screw
Successful
Check the Power
Then check for the
This procedure is described in
If the test results for this
Terminals 1 and 5 can be
6. Armature
7. Clamp
8 . Coil
9. Magnet
If the