Primary Power Cable Connections; Control Wiring; Current Transformers; Ground Connections - Siemens WL Series Instruction & Installation Manual

Type WL Low Voltage Metal-Enclosed Switchgear
Electrical Connections

Primary Power Cable Connections

Because of considerable variations in purchaser requirements
and available cables, Siemens furnishes mechanical terminal
lugs only, unless specified otherwise by the purchaser.
Important: Clearance between bare phase conductors and
to ground should be at least one inch. If this requirement is
not met, the connections should be insulated with electrical
insulating tape to achieve the required dielectric levels.
Primary and secondary cables should enter the switchgear
through the space shown on the General Arrangement drawing.
Always arrange cables in smooth curves and anchor securely to
cable supports to relieve strain on termination, and to control
cable movement under short-circuit conditions. Figure 22
shows the recommended cable lashing installation for supply
and load cables. If cable entry is from above, drill the top plate
or roof plate to suit. For outdoor installations, drill the cable
area cover to suit the conduits. If cable entry for outdoor or drip
resistant applications is through the roof, install code-approved
hubs or weather seal means.
Before the cable connections are made, phase rotation should
be checked.
Figure 22. Cable Lashing Instructions

Control Wiring

Terminal blocks are provided in the front of the switchgear for
purchaser's control wiring connections. Refer to the master
wiring diagram for wire designations. Wiring between sections
at shipping splits is connected and tagged as shown on the
master wiring diagram for purchaser's ease in field connection.
Shipping split wiring connections are made in an area on top of
the switchgear near the front of the section. A removable cover
allows access to these connections.
For ventilated dry transformer installations, a conduit is fur-
nished for wiring between switchgear and the temperature
control system box on the transformer. This conduit is
installed and wired by the purchaser in the field
For liquid filled transformer installations, the conduit is fur-
nished with the transformer for connecting to the switchgear
in the field.
Courtesy of NationalSwitchgear.com

Current Transformers

Hazardous voltage.
Will cause death or
serious injury.
Do not open-circuit the secondary of an
energized current transformer. Always
short-circuit the secondary of any current
transformer before performing maintenance
on current transformer wiring.
Current transformers for metering are generally mounted on
the stationary primary disconnect studs in the circuit breaker
compartment and are readily accessible for inspection and
replacement.
Current transformers for electronic trip device use are called
"tripping transformers." They are mounted in the circuit breaker
except when a ground fault trip element or neutral metering
element is furnished for a four wire application. In this case, a
fourth tripping transformer is mounted in the cable compart-
ment on the neutral bus or in the link between the neutral bus
and the ground bus. This will be shown on the one line diagram.

Ground Connections

A common ground bus is incorporated in all sections for prop-
erly grounding the switchgear after installation. Provisions for
connecting this ground bus to the station ground must be
made by purchaser in a reliable manner. Ground per require-
ments of NEC.

Cleaning

Hazardous voltage.
Will cause death or
serious injury.
Keep out.
Qualified personnel only.
Disconnect and lock off all power before
working on this equipment.
When switchgear installation is complete and all electrical
connections have been made, but prior to energizing, or
installing circuit breakers, all equipment must be thoroughly
cleaned using a vacuum cleaner to make certain they are
free of construction dust, chips or other debris. Do not use
pressurized air (ie., an air hose) to blow dirt and debris out
of the switchgear as this can cause foreign items to lodge
in areas from which removal will be difficult. Do not use
solvents without reading "Cleaning of Insulation" in the
"Maintenance" section.
DANGER
DANGER
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