Flux Shi Fter Trip Device; Troubleshooting - GE AKR-30 Series Maintenance Manual

SECTION 1 2- MicroVersaTriprM Trip Device (Cont.)
1 2.3

FLUX SHI FTER TRIP DEVICE

The only difference between the MicroVersaTrip and
SST flux shifter trip devices is the solenoid wind i ng. Refer
to Section 1 0.3 for details.
When replacing a MicroVersaTri p flux shifter, AMP ex­
traction tool Cat. No. 455822-2 is requ i red to remove the
socket leads from the A M P connector.
1 2.4 TROUBLESHOOTI NG
When malfunction ion is suspected, the fi rst step in
troubleshooting is to exam ine the circuit breaker and its
power system for abnormal conditions such as:
a) Breaker tripping in proper response to overcu rrents or
i ncipient ground fau lts.
b) Breaker remai ning in a tri p-free state d ue to
mechanical mai ntenance along its trip s h aft.
c) Inadvertent shunt tri p activations.
WARNING: DO NOT CHA NGE TAPS ON THE CUR­
RENT SENSORS OR A DJUST THE PROGRA MMER
UNIT SET KNOBS WHILE THE BREAKER IS CAR­
R YING CURRENT.
FLUX
SHIFTER
PROGRAMMER
HARNESS
FIG. 87 A - M I CROVERSATRIP®
COMPONENT WITH TAPPED SENSORS
64
Once it has been establ ished that the circuit breaker
can be opened and closed normally from the test position,
attention can be directed to the trip device proper. Testing
is performed by either of two methods:
1 . Cond uct high-current, single-phase tests on the
breaker using a high c urrent-low voltage test set.
NOTE: For these single-phase tests, special connec­
tions must be employed for Micro Versa Trip breakers
equipped with Ground Fault. Any single-phase input
to the programmer circuit will generate an unwanted
"ground fault" output signal which will trip the
breaker. This can be nullified either by
a) Using the Ground Fault Defeat Cable as shown in
This special test cable energizes the pro­
Fig. 93.
grammer circuit in a self-cancelling, series-parallel
connection so that its output is always zero.
2. Test the components of the MicroVersaTri p system
using portable Test Set Type TVTS1 (Fig.
pl icable test procedu res are detailed in i nstruction Book
G EK-64464.
The time-current characteristics for the MicroVersaTrip
Trip Device are given i n curves G ES-61 95 and G ES-6199.
FIG. 878 RMS-9, EPIC MICROVERSATRIP®
-
AND MVT -PLUS OR MVT -PM COMPONENTS
WITH FIXED SENSORS
88).
The ap­