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