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Equipment Description
01.4IB.51000C
PowlVac® Metal-Clad Switchgear
5kV & 15kV
I. S
Afety
I
nterlockS
AnD
p
rovISIonS
Warning and Caution labels are located in
various places. Do not remove or deface any
of these warning/caution labels.
NOTICE
1) Key Interlocks
Key interlocks are often supplied in
conjunction with disconnecting switches,
removable elements, and special
compartments where access is dependent
on other actions. The operation of key
interlock schemes is generally described
by a note or key chart on the work order
drawings.
Before placing the equipment with key
interlocks into operation, the key scheme
must be carefully checked and only proper
keys left in the locks.
All extra keys must be removed and discarded
or secured where they are accessible only in
an emergency.
NOTICE
2) Circuit Breaker Compartment Safety
Provisions
The PowlVac® circuit breaker is equipped
with a positive mechanical interlock that
prevents moving the breaker unless the
primary contacts are open. To rack the
circuit breaker in any direction, the circuit
breaker must first be opened. If equipped
with a CDR circuit breaker, the interlock
then interfaces with an actuator located
in the circuit breaker compartment of the
switchgear to hold the circuit breaker in
a “trip-free” condition while the circuit
breaker is being racked into or out of the
connected position.
Safety shutters open and close over the
stationary primary disconnect devices in
response to the movement of the circuit
breaker racking mechanism. A spring
discharge interlock is provided to discharge
the main closing spring when a circuit
breaker is inserted into or withdrawn
from the compartment. This interlock is
activated by unplugging the secondary
disconnect plug or the disconnect override
device accessory.
A breaker compartment interference plate
is provided which is designed to hinder
the insertion of an incorrect type or rating
circuit breaker into the compartment. The
breaker enclosure interference plates for
the metal-clad switchgear and the circuit
breaker are designed to allow a circuit
breaker with equal or higher voltage
and current ratings to be inserted in the
compartment and to hinder insertion of a
circuit breaker of a lower rating.
The circuit breaker rating should always be
checked against the rating of the
metal-clad switchgear. Under no
circumstances should the interference plate
be removed from the circuit breaker or the
switchgear as this action may allow the
installation of a circuit breaker not rated for
the compartment.
!
WARNING
Always verify the ratings and control scheme
of a removable element before inserting into
the equipment. Inserting an incorrectly rated
element could result in death or serious injury.