Eaton Freedom 2100 Installation And Maintenance Manual page 14

Motor control center
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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 sys-
tem. 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 high-ampere 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 mechani-
cal forces created by a high fault current. With the re-
mainder of a Freedom 21 00 MCC braced 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 and appropriate
lacing material to tie cables together where they can be
bundled and to hold them apart where they are sepa-
rated. 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.
MAKING CONNECTION
CAUTION: All incoming line compartments present
an obvious hazard when the door is opened or cov-
Fig. 20 Incoming Line Lug Connections
I.B. 8926-1
Fig. 21 Incoming Line Compartment, 2000A
ers are removed with power on. When working in
this area, the incoming feeder should be de-ener-
gized.
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 in-
stallation.
Depending on the location, size and type of the incom-
ing arrangement, remove one or more horizontal and
vertical wireway doors, and selected units to provide com-
plete access. See Part9 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
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