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I N S TA L L AT I O N , O P E R AT I O N S A N D M A I N T E N A N C E M A N U A L
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Incoming side cable
lashing (bracing) method
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Lashing scheme for connecting cables in 2500A
and 3200A main bus configurations. Add 5 wraps
for every additional 12" of incremental unit height.
Align the conduit linearly directly over or as close
as possible to the supports. Run the cable in a
convenient orientation, making sure the cable is
located against the supports before it connects
to the cable terminals. Lash the cable using the
following procedure: Wrap the line cables together
and, if provided, tie cables together with nominal
3/8-inch (9.5 mm) nylon rope or rope having a
minimum tensile strength of 2000 pounds (8896
N), at 6 inches (152 mm) and 12 inches (305 mm)
from the line terminals. Use five wraps and
complete every additional 6 inches with five wraps
or every 1 inch (25 mm) with one wrap. Use supplied
cable supports as desired. Refer to UL 891.
Individual unit wiring
Open the vertical wireway door(s) and the top and/
or bottom horizontal wireway hinged covers. All
doors can be removed, if desired, by extracting
hinge pins or removing the hinge.
CAUTION
When installing cables, be sure to not damage the
cable insulation on any sharp edges, such as steel
work or screws.
Where access to the rear of the section is available,
cables can be brought into the space behind the
vertical bus and brought forward into the front
wire trough area through any of the modular
openings in the right-hand steel support plate.
Wiring NEMA type A motor control centers
Use the following procedure to wire NEMA
Type A MCCs:
1. Remove black plastic barrier closest to unit
connection points and remove knockouts
as required.
2. Pull load cables near the unit to be wired.
Measure (allowing for cable bends), cut and strip
the cables, and feed them carefully through
barrier knockout into the unit. Terminate the
cables on the feeder or starter lugs provided in
the unit. If aluminum wire is used, coat the wire
strands with an oxide-inhibiting grease
specifically designated for use with aluminum
cable. Install plastic side barrier.
3. Pull the control wiring, then measure, cut, strip,
and terminate it on individual device terminals in
the unit.
4. When specified, an optional ground lug is
provided in each draw-out combination starter
unit for terminating a motor-frame grounding
wire. (For larger starters, the lug is mounted on
the horizontal ground bus.)
5. Use cord or plastic ties to secure all wiring. Route
the wiring to avoid interference with moving
parts and to keep it away from heat-producing
components, such as resistors and fuses.
6. Verify that the connections on all devices and
terminal blocks are tightened to their proper
torque values, as listed on the label on the
vertical wireway door.
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