Siemens 3AH Instructions, Installation, Operation, Maintenance page 29

Maintenance and Troubleshooting
Table 9. Troubleshooting (continued)
Problem
Nuisance or false close
Circuit breaker will not trip
Nuisance or false trip
Symptoms
Electrical problem
Mechanical Problem
Tripping coil, or solenoid (52T)
does not energize. There is no
tripping sound.
Tripping coil (52T) energizes. No
tripping sound is heard, and
breaker contacts do not open (ie.,
they remain closed).
Tripping coil (52T) energizes.
Tripping sound is heard, but
breaker contacts do not open.
Electrical problem
Mechanical problem
Possible Causes and Remedies
1. Nuisance or false closing signal
to secondary disconnect contact
13. Check relay logic. Correct as
required.
2. Closing coil (52SRC) terminal A2
is shorted to ground. Check to
determine if problems in wiring
or coil. Correct as required.
1. Mechanical failure of operating
mechanism. Check and contact
factory or authorized service
shop.
1. Secondary control power is de-
energized or control power fuses
are blown. Correct as indicated.
2. Damage to wiring, terminals or
connectors. Check and repair as
necessary.
3. No tripping signal to secondary
disconnect contact 1. Check for
continuity and correct relay logic.
4. Secondary disconnect contacts 1
or 2 are not engaging. Check and
replace if required.
5. Failure of trip coil (52T). Check
and replace if necessary.
6. Auxiliary switch NO contacts 23-
24 or 33-34 are open when
breaker is closed. Check linkage
and switch. Replace or adjust as
necessary.
1. Failure of tripping spring or its
mechanical linkage. Check and
replace if required.
1. Mechanical failure of operating
mechanism. Check and contact
factory or authorized service
shop.
2. One or more of the vacuum in-
terrupters are held closed. Check
and replace as necessary.
1. Tripping signal remains energized
on secondary disconnect contct 1.
Check for improper relay logic.
1. Mechanical failure of operating
mechanism. Check and contact
factory or authorized service
shop.
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