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E VOLUTI ON S E R I E S E9 0 0 0
M OTO R CO N T R O L C EN T ER
Wiring NEMA type B motor control centers
Use the following procedure to wire
NEMA Type B 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 feeder
cables directly on the lugs 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.
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19
Plenum-less arc-
resistant equipment.
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19
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20
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20
Cable entry cut out area.
Shown in Figure 18 there is no restrictions in this
setup as the customer can use the hatched area of
the top from the plenum for cable entry. The
available space varies per the depth and width of
the section. Do not make any cuts on top of
sections that don’t have incoming cables, to reduce
the chance of arc propagation.
Arc-resistant plenum-less equipment
Plenum-less equipment design uses thin aluminum
sheet metal attached to the top of the section with
nylon rivet, when an arc instance occurs the top
side of the section is the only one to deform
releasing any gas.
In Figure 19 shows the top view of a plenum-less
equipment, for a plenum-less equipment the thin
aluminum sheet metal is attached to the section
with nylon rivet, when an arc flash occurs the top
side of the section is the only one to deform
releasing any gas.
For the cable entry on a plenum-less equipment it
is only allowed to do cuts on the front side of the
top section. Figure 20 shows the allowed area to do
a cut for incoming cable outside the perimeter
frame area and the steel strips that holds together
the aluminum sheet metal to the section.
1.22 in
1.22 in
2.8 in
0.55 in
Front side
Rear side
Steel strip
Bolts:
2 used for each side
(front and rear)
of the section
Nylon rivets:
5 used for each side
(front and rear)
of the section
Thin aluminium
sheet metal
Front side
Rear side
Main bus channel
