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Hazardous voltage.
Will cause death or serious
personal injury.
Turn off power before working on
this equipment.
3.10 Pull box installation
Refer to Figure 15 for the following procedure.
1. Remove top front conduit plate (A) from
motor control center structure by removing
two screws (B). There are two front plates on
back-to-back motor control centers.
2. Remove two rear screws (C).
3. Remove the top two screws holding on the bus
insulator cover (E). Do this to both sides of a
back-to-back motor control center.
4. Install barrier (F) and replace the screws from
step 3.
5. Remove top plate of pull box (G).
6. Place pull box on MCC and screw down using
four 1/4 - 20 x 3/4" taptite screws. The rear
mounting holes may have to be drilled on front
only motor control centers. Use the pull box/top
hat as a drilling template.
7. Replace top plate that was removed in step five.
3.11 Incoming power
connections
Note: Remove top covers before cutting holes for
conduit to prevent metal chips from falling into the
motor control center. Conduits should be carefully
installed to prevent moisture or water from entering
and accumulating within the enclosure. All conduits
(including stubs) should be bonded to the motor
control center. After all shipping sections are in
place, leveled, and joined together into a single
motor control center, cables may be pulled and top
entry conduit may be installed. Bottom entry conduit
will have been stubbed through the floor at the
proper locations prior to placement of the motor
control center. The incoming source cables may be
connected at this time, however, the power source
disconnecting means must remain open and locked
out until all wiring is completed and the entire
system has been checked out.
Care must be exercised to make sure that the lugs
which have been provided are suitable for use
with the type of cables being installed in the motor
control center. If crimp lugs are supplied, use only
the crimping tool recommended by the lug
manufacturer.
Care should be exercised in stripping insulation
from the conductors to prevent nicking the
conductor. Tighten all screw lugs and bolted
electrical connections to the specified torque listed
in the table in the maintenance section of this
instruction manual.
To minimize the length of unsupported cable,
the shortest, most direct routing should be chosen.
However, the largest practical bending radii should
be maintained to avoid damaging the insulation
and to avoid causing terminals to loosen. All
cables entering the motor control center must be
adequately supported and restrained to withstand
the maximum fault current capable of being
delivered by the source. The recommended distances
between straps for 80 pound rated strap is 6 inches
for 25 kA bracing, 4 inches for 42 kA bracing and
3 inches for 65 kA bracing. Using a strap rated less
than 80 pounds will require the spacing distances
to be reduced. For 100 kA bracing, cables must
be supported in accordance with the special
instructions provided with the motor control center.
tiastar™ Motor Control Centers Instruction Manual Installation
15
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