GE Industrial Solutions EntelliGuard 3200–5000 A Frames, 240–600 Vac - Manual (Page 16)

EntelliGuard™ 3200–5000 A Power Circuit Breakers
Chapter 3. Breaker Operation
8
Spring Discharge Interlock
The spring discharge interlock functions in conjunction
with the circuit breaker’s draw-out interlock and a
compartment-mounted cam to discharge the closing and
opening springs before the breaker can be withdrawn
from the compartment. It includes an inverted “T” rod
beneath the circuit breaker, which has two functions.
In the DISC position, the inverted “T” rod prevents the
breaker from being further withdrawn from the
compartment until the closing and opening springs are
discharged. In the CONN position, the inverted “T” rod
aligns beneath a stop bracket in the compartment which
blocks lifting of the “T” rod and prevents the spring
discharge interlock lever from being used to close the
circuit breaker.
When the circuit breaker is racked to the DISC position,
the draw-out interlock pin is lifted by the compartment
cam. This holds the circuit breaker trip shaft & latch in a
trip-free position. The breaker cannot be closed.
Depressing the spring discharge lever releases the closing
spring energy and the mechanism crashes (closing springs
discharge but breaker does not close). Depressing the
lever also lifts the “T” rod beneath the breaker, lifting it
above the ramped interlock beneath the breaker, thus
releasing the breaker to rollout to the fully withdrawn
position.
Note: If the breaker is out of the switchgear compartment,
the spring discharge interlock will act as a closing lever
since no other interlocks will be holding the trip shaft in a
trip-free position as the closing spring energy is released.
3.4 Equipment Interlocks
Additional optional interlocks may be furnished with the
breaker enclosure. The Key Interlock prevents the breaker
from closing when the interlock is engaged and requires
one or more keys to operate. The Door Interlock prevents
opening of the enclosure door when the breaker is in the
CONN position. It can be defeated for authorized access.
The door can be opened by racking the breaker to the
TEST or DISC position.