Siemens 3AH Series Instructions Manual page 34

Maintenance andTroubleshooting
8. (continued)
Trou bleshooti ng
Table
Problem
N uisance or false close
Circuit breaker will n ot trip
N uisance or false trip
Symptoms
Electrical problem
M echa n ical Problem
Trip coil, (52T) does not energize:
There is no tripping sound.
Trip coil (52T) energizes. No tripping
sound is heard, a n d circuit breaker
contacts do not open (i.e .. , they re-
main closed).
Trip coil (52T) energ izes. Tripping
sou nd is heard, but circu itbreaker
contacts do not open.
Electrical problem
Mech a n ical problem
Possible Causes and Remedies
1. N u isance or false closing signal
to secondary discon nect contact
A2. Check relay logic. Correct as
req u ired.
2 . Close coil (52SRC) terminal A2 is
shorted to g round. Check to deter-
mine if problems in wiring or coil.
Correct as required.
1. Mech a n ical failure of operating
mech a n ism. Check and contact
factory or a uthorized service shop.
1. Second a ry control power is de-
energized or control power fus-
esare blown. Correct as indicated.
2. Damage to wiring, terminals or
con nectors. Check and repair as
necessary.
3. N o tripping signal to secondary
disconnect contact C2. Check for-
contin uity a n d correct relay logic.
4. Secondary d isconnect contacts
C2 or 02 a re not enga g i n g . Check-
a n d replace if req u ired .
5. Fai l u re of trip coil (52T). Check
and replace if necessa ry.
6. Auxiliary switch 52a/b N O contacts
23-24 or 33-34 are open when cir-
c u it breaker is closed.
Check l i n kage and switch. Replace
or adjust as necessa ry.
1. Fai l u re of opening spring or its
mechanical l inkage. Check a nd
replace if required .
1. Mech a n ical failure of operating
mechan ism . Check a n d contact
factory or a uthorized service
shop.
2. One or more of the vacuum in-
terrupters a re held closed. Check
and replace as necessary.
1.Tripping signal remains energized
on secondary disconnect contact
C2. Check for improper relay logic.
1. Mech a n ical failure of operating
mech anism. Check and contact
factory or authorized service shop.
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