Vehicle Description
9
1. Trip-free roller:
If the trip-free roller does not fit in the upper or lower
cavity of the cubicle mounted moveable cam as
required, or actuation of the elevating mechanism
handle does not immediately discharge the springs and
open the circuit breaker, the trip-free roller may be
adjusted.
To adjust the location of the trip-free roller, first loosen
both locking nuts located on the adjustable rod. When
nuts are loosened, the trip-free roller may be adjusted
in/out by turning the adjustable rod (on some models,
it may be necessary to loosen the locknuts, and
disassemble the upper clevis from the associated cam
plate to obtain freedom of adjustment). Turning the
adjustable rod will result in a radial movement (in, out,
up, and down) of the cam plate and trip-free roller related
to the pivot point of the cam plate.
If problems still occur after performing the above actions,
contact the local Siemens office for information.
MOC Actuator (Refer to Figure 4)
Siemens recommends replacement of the original GE
52STA with a Siemens 52STA (5kV, 250MVA — P/N 18-669-
255-502 and for all other ratings — P/N 18-669-255-501.)
If requested, the Siemens type GER circuit breakers can
come equipped with a MOC actuator. This is provided to
actuate the original manufacturer’s designated 52STA
auxiliary switch mounted in the existing cubicle.
The Siemens MOC actuator has a total travel from circuit
breaker open to circuit breaker closed position of 1.062
±
0.062”. The travel applies approximately 0.94” total
displacement of the cubicle mounted 52STA auxiliary switch
at proper cubicle settings.
The recommended setting of the MOC actuator is described
in the “MOC Actuator” Illustration, (Figure 4).
Continuous Current Interlock
The continuous current interlock functions to ensure that
circuit breakers and cubicle of like continuous current rating
are applied, and that circuit breakers with dissimilar
continuous current ratings are excluded from cubicles of
unlike continuous current ratings.
The continuous current interlocks applied on the type GER
circuit breakers are designed to match in detail and
mounting location those of the interlocks applied on the
original manufacturer’s circuit breaker.