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Installation
01.4IB.67000
After the equipment has been installed and
all connections made, it should be tested
and inspected before putting it in service.
Although the equipment and devices have
been completely tested at the factory, a final
field test should be made to ensure that the
equipment has been properly installed and
that all connections are correct and have not
become loose in transportation.
If users perform AC hipot testing on high
voltage cables used to connect the switchgear
to loads, the following testing practices are
recommended:
1. AC hipot testing voltage must be limited to
no more than 27kV (75% of 36kV). DC hipot
testing is not recommended. If DC hipot
testing must be performed, consult with
Powell prior to testing.
2. Surge arrestors, if present, must be
disconnected before hipot testing.
3. Voltage Transformers and Control Power
Transformers must be moved to the
“DISCONNECTED” position before AC hipot
testing.
Directions for testing devices such as relays,
instruments and meters are given in the
instruction bulletin furnished for each device.
The settings of the protective relays must
be coordinated with the other relays on the
system and therefore, these relays must be set
by the user. General instruction bulletins are
furnished with the equipment, containing the
instruction material for all individual devices
used in the equipment.
When transformers are furnished to supply
the control power, the primary taps should be
selected so that the control voltage indicated
on the wiring diagram is obtained on the
secondary of the transformer. When a battery
is used to supply the control power, the cables
from the battery to the switchgear should be
large enough to avoid excessive voltage drop.
When supplied by a battery, the voltage at the
terminals of the operating coils, shall not be
less than 112.5 volts for 125 volt coils and 225
volts for 250 volt coils.
The operation of the breaker with its associated
devices may be tested in the unit while the
equipment control power is energized by
racking the breaker into the test position
and engaging the secondary coupler. This is
accomplished by lowering the handle on the
right hand side of the breaker mechanism and
pushing forward until the coupler engages.
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