Eaton Freedom 2100 Installation And Maintenance Manual page 6

Motor control center
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mounted on a level surface. The foundation furnished by the
purchaser must be true and level, or the bottom frames must be
shimmed to support the entire base in a true plane. It is recom-
mended that leveled channel sills under both the front and rear
of the control center be used to provide this level base. Drill and
tap the channel sills for mounting bolts in accordance with the
applicable floor plan drawing and then either install the MCC level
with, or on top of, the finished floor. If sills are grouted in con-
crete, the mounting bolts should be screwed in place and remain
until the concrete has hardened.
4. For bottom entry, position the motor control center so that the
conduit stubs or floor openings are located in the shaded areas
shown on the MCC floor plan drawings (refer to pages 30 and 31
for floor plan dimensions). The shaded areas represent the open
space available for conduit entry through the bottom of each sec-
tion. A shaded area may be restricted if large controllers or
autotransformers are mounted in the bottom of the sections. If
optional bottom plates are supplied, the plates may be removed
and drilled for conduit entry.
5. Install the MCC in its final position, progressively leveling each
section and bolting the frames together if they are separated. If
necessary, secure the MCC to walls or other supporting surfaces.
Do not depend on wooden plugs driven into holes in masonry,
concrete, plaster, or similar materials. See NEC 110-13.
6. If two or more shipping sections are to be joined into an integral
assembly or a shipping section is to be joined to an existing sec-
tion, refer to paragraphs below before proceeding with the instal-
lation.
7. Ground and bond the motor control center as follows:
a) Motor control centers used as service equipment for a grounded
system or as an incoming line section for a separately-derived
previously grounded system:
i)
Run a grounding electrode conductor (ground wire) having a size
in accordance with NEC 250-94 from the grounding electrode to
the MCC ground bus or ground terminal provided. See also NEC
250-91 (a) and 92(b).
ii)
If the system is grounded at any point ahead of the MCC,
the grounded conductor must be run to the MCC in accordance
with NEC 25023(b), and connected to the ground bus terminal.
iii)
Do not make any connections to ground on the load
side of any neutral disconnecting line or any sensor used for
ground-fault protection. Do not connect outgoing grounding con-
ductors to the neutral.
b) Motor control centers used as service equipment for an
ungrounded system or as an incoming line section for a sepa-
rately-derived previously ungrounded system:
I.B. 8926-1
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