Vehicle Description
Figure 3 Trip-Free/Spring Dump Interlock (Circuit Breaker in Fully Connected Position)
3. Attempt to manually charge the closing spring. The
closing spring should extend as expected, but fail to
latch in the extended position due to the displacement
of the close latch lever.
As the closing spring cannot maintain a latched condition,
and the trip latch lever is displaced, it is impossible to
charge the springs and close the circuit breaker during the
racking cycle.
Circuit Breaker in Connect Position (Refer to Figure 3)
Figure 3 is a pictorial representation of the circuit breaker
in the Connect position.
Note that in this position, the trip-free roller resides in the
upper cavity of the cubicle mounted moveable cam. It is
important to note that there should be a 0.062” to 0.125”
gap between the bottom of the trip-free roller and the top
of the stationary flag associated with the cubicle mounted
elevating mechanism. (Refer to section entitled “Cubicle
Preparation”, page 3, for cubicle adjustment)
In the Connect position with the trip-free roller residing as
required in the upper cavity of the moveable cam, the
circuit breaker is now free to perform all required functions.
The enlarged view of the operating mechanism shows the
circuit breaker operator closed with springs charged. Note
that all items displaced during the racking procedure have
returned to the state required to allow the circuit breaker to
be charged and latched closed.
It is important to verify that the circuit breaker will perform
as expected in the fully connected position. Follow the
following procedure to test the functioning of the operating
mechanism in the fully connect position.
1. On a de-energized bus, rack the circuit breaker to the
fully Connect position. Successful function of the trip-
free/spring dump interlock will result in the circuit breaker
arriving in the Connect position in an open state with
springs discharged.
7
Hazardous voltages and high-speed
moving parts. Will cause death, serious
injury, and property damage.
De-energize before working on this equip-
ment.
Do not by-pass interlocks or otherwise make
interlocks inoperative.
