26
5.2.3
Troubleshooting of 3AH0 VCBs
Problem
Symptoms / Effect
Possible Causes / Reasons
Remedial Measures
Breaker
fails to
close.
close.
wiring.
19 or A2 of socket
circuit.
5. Unoperational closing release.
6. Aux. switch (S1) contacts 21-22
are open when the breaker is
with aux. switch.
7. Unoperational anti-pumping
wiring.
4. Unoperational charging motor.
operate
6. Mechanical failure of operating
mechanism.
centres.
Mechanical failure of operating
mechanism.
centres.
Nuisance
or false
closing of
breaker
1. Electrical problem
terminal 19 or A2.
2. Terminal A2 of closing release is
wiring or release. Correct as per
requirement.
2. Mechanical problem
Mechanical failure of operating
mechanism
centres.
Breaker
trip.
not trip.
2. There is no tripping
wiring.
4 or C2 of socket.
circuit.
5. Unoperational tripping release.
6. Aux. switch (S1) contacts 23-24
are open when the breaker is
with aux. switch.
Nuisance
or false
tripping
of breaker
1. Electrical problem
terminal 4 or C2.
2. Mechanical problem
2. Mechanical failure of operating
mechanism.
centres.
Summary of Contents for 8BK80
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