Freedom 2100 Motor Control Center Installation - emsco

13 I.B. 8926-1A
When the MCC has a main disconnect, bring the
incoming lines (the feeders) to the line terminals of
the circuit breaker or circuit interrupter. The load side
of the circuit breaker or the load side of the fuses
associated with the circuit interrupter has already
been connected to the MCC bus bar distribution
system. In the case of main disconnects rated 400
amperes or less, this load connection is made by
stab connections to vertical bus bars which connect
to the horizontal bus distribution system. See Figure
17.
INCOMING LINE LUGS
Where the overcurrent protection for the MCC is at a
remote location, the MCC feeder lines are
connected to incoming line lugs attached to the bus
bar distribution system. See Figure 20. For highampere
rated horizontal bus bar systems, the
incoming line lugs are mounted on vertical risers,
which connect to the horizontal bus bars. See Figure
21.
SHORT-CIRCUIT BRACING
All incoming lines to either incoming line lugs or to
main disconnects must be braced to withstand the
mechanical forces created by a high fault current.
With the remainder of a Freedom 2100 MCC braed
for not less than 65,000 amperes (rms symmetrical),
the installing electrician needs to anchor the cables
at the incoming line connections sufficiently and
tighten the lugs correctly. Each incoming line
compartment is equipped with a two-piece spreader
bar located about nine inches from the conduit entry.
Use this spreader bar an appropriate lacing material
to tie cables together where they can be bundled
and to hold them apart where they are separated. In
other words, position the incoming line cables and
then anchor them in place. See Figure 22 and the
instruction sheet inside of the MCC.
Fig.20 Incoming Line Lug Connections
Fig. 21 Incoming Line Compartment, 2000A
MAKING CONNECTION
CAUTION: All incoming line compartments
present an obvious hazard when the door is
opened or covers are removed with power on.
When working in this area, the incoming feeder
should be de-energized.
Before beginning work on incoming line connections,
refer to all drawings furnished by Cutler Hammer as
well as all applicable contract drawings for the
particular installation.
Depending on the location, size and type of the
incoming arrangement, remove one or more
horizontal and vertical wireway doors, and selected
units to provide complete access. See Part 9 for unit
removal instructions.
For top entry, the top cover plates are easily
removed for drilling or punching operations.
Fig. 22 Spreader Bar For Top Entry