Maintenance and troubleshooting
Problem Symptoms Possible causes and remedies
Circuit breaker fails to close. Closing spring will not automatically charge. 1.    Secondary control circuit is de-energized or 
control circuit fuses are blown. Check and 
energize or replace if necessary.
2.    Damage to wiring, terminals or connectors. 
Check and repair as necessary.
3.    Failure of charging motor (88). Replace if 
required.
4.    Motor cut-off switch LS21 or LS22 fails to 
operate. Replace if necessary.
5.    Mechanical failure of operating mechanism. 
Check and contact regional service centers, 
the factory or telephone Siemens field 
service at  +1 (800) 347-6659 or +1 (919) 
365-2200 outside the U.S.  
Closing springs 
charge, but circuit 
breaker does not close.
Closing coil or solenoid 
(52SRC) fails to 
energize. No sound of 
circuit breaker closing.
1.    Secondary control circuit de-energized or 
control circuit fuses blown. Correct as 
indicated.
2.    No closing signal to XOA2. Check for 
continuity and correct protective relay logic.
3.    Failure of anti-pump relay (52Y) contacts 21 
to 22, 31 to 32 or 13 to 14. Check and 
replace as required.
4.    Failure of close coil (solenoid) (52SRC). 
Check and replace as required.
5.    Auxiliary switch NC contacts 41 to 42 are 
open when circuit breaker contacts are 
open. Check linkage and switch. Replace or 
adjust as necessary.
6.    Spring-charged switch LS9 NO contacts 
remain open after springs are charged. 
Check and replace as required.
Closing coil energizes. 
Sound of circuit breaker 
closing is heard but 
circuit breaker contacts 
do not close.
1.    Mechanical failure of operating mechanism. 
Check and contact regional service centers, 
the factory or telephone Siemens field 
service at  +1 (800) 347-6659 or +1 (919) 
365-2200 outside the U.S.
Table 8: Troubleshooting
35