10
I.B. 8926-1A
Fig. 13 Splice Plate Attached to Freedom 2100
Ground Bus at Bottom.
Fig. 14 Splice Plate Attached to Freedom 2100
Neutral Bus.
Part 4
INSTALLING CONDUIT AND WIRING
CONDUIT
Install conduit in such a manner as to prevent water
from entering and accumulating in the conduit or the
enclosure. Eliminate sags in conduit. Have the
conduit enter the motor control center (MCC) in the
areas designated for conduit entry on the plan
views. See pages 31 and 32 of this booklet and
outline drawings shipped with the MCC. Keeping
conduit within the shaded areas shown in the plan
views will avoid cable interference with structural
members and live bus. See Part 12.
WIRING
Install the line and load conductors sized in
accordance with the NEC.
Use copper wire only
for control terminations. Use copper wire only
for power terminations unless they are marked
“CU/AL”.
Use conductors with a temperature rating
of 75
°
C or higher, but regardless of the insulation
temperature rating select the wire size on the basis
of 75
°
C wire ampacity. Using a higher temperature
wire ampacity table often results in a smaller cross-
section of copper available for carrying heat away
from terminals.
Install insulated wire and cable at a temperature
sufficiently warm to prevent the insulation from
cracking or splitting.
When more than one conduit is run from a common
source or to a common load, be sure to have each
conduit carry conductors from each phase and the
same number of conductors per phase. If the phase
conductors are not distributed uniformly, eddy
currents will be generated in the steel between the
conduits.
Locate conductors within the MCC to avoid physical
damage and to avoid overheating. Secure incoming
power lines in a manner adequate to withstand the
forces which will act to separate the conductors
under short-circuit conditions. Use the cable ties
furnished in both horizontal and vertical wireways to
support the load and interconnection wire. Use a
shielded communications cable inside of flexible
metal conduit to protect very low voltage signals
transmitted to or from a computer or programmable
controller.
Lugs furnished with the MCC and its components
are for Class B and Class C stranding. Verify the
compatibility of wire size, type, and stranding with
the lugs furnished. Where they are not compatible,
change the wire or lugs accordingly. If crimp lugs are
used, crimp with the tools recommended by the
manufacturer.
Use care in stripping insulation to avoid nicking or
ringing the metal.
All field wiring to control units should be made in
accordance with the wiring drawings that are
furnished with the control center. Load and control
wiring can be brought in through the upper and/or
lower horizontal wireways. Determine the type of
wiring installed in the control center (NEMA Type B
or C) and proceed per the following appropriate
paragraph.
The phase sequence of the power circuit load
terminals (left-to-right: T1, T2, T3) in units
