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R E L I A G E A R LV M C C LO W V O LTA G E M OTO R C O N T R O L C E N T E R
34
Testing and inspection
After the equipment has been installed and all
connection made, it must be tested and inspected
before it is put in service. Although the equipment
and devices have been tested at the factory, a final
field test must be made to be sure that the
equipment has been properly installed and that all
connections are correct.
The equipment must be completely de-energized
WARNING
while the tests are in progress.
Relays, instruments and meters
Directions for testing relays, instruments, and
meters are given in the instruction book furnished
for each device. The proper settings of the
protective relays and circuit breaker trip units are
normally determined from a complete power
system coordination study performed by the
purchaser or their consultant; therefore, the
settings of these devices must be made by the
purchaser.
The trip setting adjustments of the trip unit for
NOTICE
each circuit breaker may be at any setting when
shipped from the factory and must be correctly set
prior to energization of the equipment. General
instructions for setting the relays are given in the
applicable Relay or Trip unit instruction book. The
extent ofthe tests on the equipment as a whole will
depend on the type and function of the equipment.
Tests which should be performed, however, include
circuit breaker operation and MCC electrical
insulation, phasing, and grounding checks.
Key interlocks
When equipped, after initial installation of the MCC
equipment, all necessary interlock keys should be
inserted into the appropriate locks and all spare
keys should be stored in a location in accordance
with the owner's established procedures.
Refer to the key interlock schematic included in the
CAUTION
summary furnished with the equipment to
determine the sequence of operation and the
correct number of operating keys required. This
precaution is necesarry since the improper use of
spare keys will defeat the interlocking scheme.
Breaker operation test
All compartments housing PBII / Emax 2 circuit
draw-out breakers have a TEST position in which
the breaker primary contacts are disconnected
while the secondary contacts are still engaged. This
TEST position permits complete testing of the
electrical control circuit without energizing the
primary power circuit. When the breaker is first put
into service.
Its control circuit must be thoroughly tested while
in this position to make sure that all closing and
tripping circuits are complete and functioning
properly. The TEST position is not suitable for
inspection and maintenance of the breaker and
should therefore be used only for testing breaker
operation. Refer to the appropriate breaker
instruction manual for other preoperational checks
on the breakers. See 1SDH001000R0002.
NOTICE
The above feature is not available with any fixed
type version circuit breakers or Tmax XT MCCs.
Trip units
The complete trip system is comprised of the
following components:
• Solid-state trip unit rating plug
• Phase current sensors
• Flux shift magnetic trip device
• When applicable, a neutral sensor for units
containing a ground fault trip element.
All components, except the neutral sennsor, are
integrally mounted in the circuit breaker. When
used, the neutral sensor is separately mounted in
the bus or cable compartment of the MCC. In draw-
out construction, it is automatically connected to
the trip unit in the breaker via a draw-out
secondary disconnect terminal.
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