11
Instruction Booklet
IB02201004E
Effective October 2017
Revision #4
Instructions for installation, operation, and
maintenance of 38 kV type VacClad-W,
150 BIL switchgear indoor housings
EATON
www.eaton.com
Section 3: Description of VacClad-W
switchgear
3.1 Safety features
Eaton VacClad-W switchgear is manufactured with several built-in
interlocks . These built-in features are intended to protect persons
working on the equipment .
CAUTION
NEVER MAKE INTERLOCKS INOPERATIVE. DOING SO CAN DAMAGE
PROPERTY AND CAUSE SEVERE INJURY.
1 .
Coding plates (see Figure 15)
A coding plate is fastened to the bottom front edge of the
breaker compartment . There is also a coding plate fastened to
the front of the breaker . If the breaker has a lower interrupting
rating than the rating of the compartment, or if the voltage and
continuous current characteristics do not match, the coding plate
on the compartment will prevent the entrance of the breaker into
the compartment .
otee:
N
Even with the coding plates, it is possible to put a breaker into the
compartment whose control wiring is not coordinated with that of the com-
partment . Always check the shop order drawing to make sure the control wir-
ing of the breaker and the compartment are the same .
2 .
Automatic shutter
Automatic safety shutters in the breaker compartment, shown
in Figures 10 and 11, cover the primary disconnecting contacts
when the breaker is withdrawn from the operating position
(Connect position) to the Disconnect or Test positions . The shut-
ters prevent persons who are working on the switchgear from
accidentally touching the primary contacts . Provisions are pro-
vided to lock the breaker compartment shutters open or closed .
Shutters also cover the primary disconnecting contacts for
drawout transformers (see Figure 7) .
CAUTION
NEVER MAKE INTERLOCKS INOPERATIVE. DOING SO CAN DAMAGE
PROPERTY AND CAUSE SEVERE INJURY. DO NOT MANUALLY RAISE OR
REMOVE THE SHUTTER UNLESS THE MAIN CONTACTS ARE DE ENERGIZED
AND SAFETY PROCEDURES HAVE BEEN INITIATED TO MAKE SURE THE
CIRCUITS CANNOT REENERGIZE. FAILURE TO EXERCISE CAUTION MAY
RESULT IN BODILY INJURY AND PROPERTY DAMAGE.
Figure 10. Breaker Compartment with Shutters Closed.
Safety
Shutters
Lock Closed
Bracket
Figure 11. Breaker Compartment with Shutters Latched Open.
3 .
Ring type current transformers
The ring type current transformers are mounted so they slip over
the primary disconnecting contact insulating high voltage termi-
nals at the rear wall of the breaker compartment . There is space
for a maximum of four standard accuracy transformers per phase
(two on each side of the breaker) or two high accuracy per phase
(one on each side of the breaker) .
The current transformers are mounted so they can be reached
from the front of the enclosure (see Figure 11) . The polarity
marks on the current transformers show the relative instanta-
neous polarity in the primary and secondary windings . The dia-
grams show how to connect the transformers to give the polarity
needed to operate relays and instruments .
4 .
Key interlocks
Keylock interlocks are often supplied in conjunction with discon-
necting switches, dummy elements, and special compartments
to which access is to be denied unless the circuit breakers con-
trolling the power to these no-load-switching devices have been
withdrawn to the Test position . The operation of key interlock
schemes is generally described by a note or keying chart on
the shop order assembly drawings . The circuit breaker pan is
equipped with provisions to mount the kirk key to it . Refer to
Figure 13 for the location of these provisions .
CAUTION
TO FACILITATE MANUFACTURE AND INSTALLATION PROCEDURES, A KEY
IS USUALLY SUPPLIED WITH EACH LOCK. BEFORE PLACING SWITCHGEAR
WITH KEY INTERLOCKS IN OPERATION, THE KEY SCHEME MUST BE
CAREFULLY CHECKED AND ONLY THE PROPER KEYS LEFT IN THE LOCKS.
ALL EXTRA KEYS MUST BE REMOVED AND DESTROYED OR STORED
WHERE THEY ARE NOT AVAILABLE TO OPERATING PERSONNEL. THIS
PROCEDURE IS NECESSARY BECAUSE IMPROPER USE OF SPARE KEYS
WILL DEFEAT THE INTERLOCKING SCHEME.
5 .
Lockout-tagout (LOTO) features
Shutter LOTO
Lockout-tagout provisions are featured on the top and bottom
shutters . In order to lockout the shutters in the closed position,
a LOTO option can be inserted through the provisions on the
shutter bracket and the enclosure bracket (see Figure 12) .
Shutter Latch
Primary Disconnections Contacts
Current Transformers