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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
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Wiring NEMA type B motor control centers
45
Use the following procedure to wire NEMA
Typical Type C
terminal board at the
type B MCCs:
top of a section
1. Remove black plastic barrier closest to unit
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connection points and remove knockouts
46
Typical Type C
as required.
terminal baords in
2. Pull load cables near the unit to be wired.
multiple sections
Measure (allowing for cable bends), cut and strip
the cables, and feed them carefully through
barrier knockout into the unit. Terminate feeder
cables directly on the lugsg on the disconnect.
Connect the motor leads at the starter terminals
if either of these conditions is met:
a. The motor control center is furnished as
"NEMA B-D wiring" (where D=Device) or;
b. The starter is NEMA size 6 or smaller.
Connect the motor leads to the starter at the T1,
T2, and T3 terminals if these conditions are met:
a. The equipment is furnished as "NEMA B-T"
wiring and;
b. The starter is NEMA size 2 or smaller.
Install plastic side barrier after power and control
wiring in Step 4 is complete. Aluminum wire is not
recommended for this product.
3. Pull the control wiring, then measure, cut, strip
and terminate it at the terminal blocks provided
within the unit. Optionally, control terminal
blocks may be pulled apart and the plastic knock-
outs removed to allow wiring outside the bucket.
The terminal blocks can then be placed back
through the plastic knockout openings and
reinstalled. This method allows wiring to
terminal blocks outside the confines of the
starter 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.
Wiring NEMA type C motor control centers
Master terminal boards in NEMA Type C motor
control centers are provided in the larger top or
bottom horizontal wireway of each vertical section.
(Refer to the drawings for the locations of master
terminal boards.) Figure 45 and Figure 46 show
typical Type C terminal board arrangements.
These terminal boards are connected at the factory
to control terminal blocks of plug-in units in each
vertical section.
Wiring diagrams show these terminal points. These
terminal blocks are also factory wired to the T1, T2
and T3 motor-lead terminals for each NEMA size 1–2
starter unit in each vertical section. Field
connections to these control and load terminals
should be made at the master terminal boards.
Make field connections to all feeders and motor
loads for starters larger than NEMA size 2 as
described for NEMA Type B motor control centers.
Optional grounding lug can be provided in each
Plug-in unit if vertical ground bus is specified.
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45
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46
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