Shunt Trip Attachment - Westinghouse DB-50 Instructions Manual

P a g e 2 6
E ne rgize relay operating coil .
close the breaker manually.
release arm should operate the relay trip
assembly and the
should open the relay contacts just before
the breaker latches . This position can best
be determined by watching the pawl in the
breaker operating mechanism, which should
snap in p lace just after the relay contacts
open. If this operation sequence is not
correct , the relay release arm should be
bent to suit . M ake sure that the relay re­
lease arm does not rub on either s ide of the
relay trip assembly lever aperture . When
the breaker is latched , de-energizing and
then energizing the relay operating coil
should not cause the relay contacts to move
toward the closed pos ition. Trip bre ake r .
Reconnect clos ing coil le ads t o the con­
trol circuit wiring. Check e lectric clos ing
of breake r .
0
LO C AT I O N
16.
Fig.
Slowly
The relay
relay trip assembly
Shunt Trip Attachment - Location and Construction Details
SHUNT TRIP ATTACHM E N T
The shunt trip mounts o n top of the platform
immediately to the right of the operating
mechanism. (See F ig. 1 6 . )
It i s non-adjustable and is intended for
intermittent duty only. The shunt trip c ir­
cuit must always be opened by an auxiliary
switch contact.
tabulated in Table No . 2 , P age 7.
Inspection
With the breaker
manually push the moving core against the
stationary core and
handle to the closed position. The breaker
should be trip free.
The trip lever of the shunt trip should
have from 1 / 32 to 1 / 8-inch clearance to
the trip bar.
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S T A T I O N A R Y
C O I L
C O R E 3 0 0
D E TA I LS
Tripping currents are
in the open position,
rotate the breaker
F R A M E
M O V I N G
C O R E
T R I P B A R
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