IB 6.2.7.7-3
4
INTRODUCTION
This manual contains instructions for inspection,
application, installation, operation, testing,
adjustment and maintenance of all VHK Model
20/21 and VHKR Model 80
vacuum power circuit
breakers. Use of these instructions will facilitate
proper application and maintenance of the circuit
breaker and prolong its life and usefulness.
The specific ratings for each breaker are located
on each Breaker Nameplate.
Throughout this manual, there are three terms that
must be heeded.
CAUTION
Not adhering to these instructions can result in
damage to the breaker.
WARNING
Not adhering to these instructions can result in
personal injury or DEATH, and damage to the
breaker.
DANGER
Not adhering to these instructions will result in
personal injury or DEATH, and permanent damage
to the breaker and other equipment.
RECEIVING AND STORAGE
Immediately upon receipt of the circuit breaker,
examine it to determine if any damage or loss was
sustained during transit. If abuse or incorrect
handling is evident, file a damage claim at once
with the carrier and promptly notify the nearest
District Office. The company is not responsible for
damage of goods after delivery to the carrier. We
will, however, lend assistance if notified of claims.
Unpack the circuit breaker as soon as possible
after receipt. If unpacking is delayed, difficulty
may be experienced in making a claim for
damages not evident upon receipt. Use care
during unpacking in order to avoid damaging any
of the circuit breaker parts. Check the contents of
each device against the packing list before
discarding any packing material. If any shortage
of material is discovered, promptly notify the
nearest District Office. Information specifying the
purchase order number, device serial numbers
and part numbers of the damaged or missing
parts should accompany the claim.
The circuit breaker should be installed in its
permanent location as soon as possible. If the
breaker is not to placed into service for some time,
it is advisable to provide some means of
protection. This may be done by keeping the
breaker in its original shipping crate and storing it
in a warm, dry, uncontaminated atmosphere. If
the breaker cannot be stored properly due to
circumstances beyond your control, it must be
thoroughly checked before being put into service.
This is to insure it has not absorbed any moisture,
or has become rusted or generally contaminated
in any way.
INSTALLATION
General
Prior to installation of the circuit breaker into the
compartment, certain preliminary inspections
should be made to insure proper operation. This
section lists the recommended inspection
procedures.
ABB
VHK vacuum
circuit breakers are shipped with
the contacts closed, Closing Springs discharged
and Opening Springs charged. This is to protect
against the possibility of the contacts striking the
inside of the vacuum interrupter enclosure and
damaging themselves during shipping.
WARNING
Prior to any disassembly or inspection of the circuit
breaker, the closing springs must be discharged,
and the breaker should be open. Failing to do so
could result in personal injury.
If the circuit breaker is equipped with an
Undervoltage Trip Device (a.k.a.,
UVTD
), the
Retaining Strap applied to the
UVTD
at the factory
must be removed. The Retaining Strap was
applied to hold the Armature of the
UVTD
in the
energized position so the breaker could be closed.
