Step 3 - Terminate conduits
See Figure 2.
• Terminate the feeder conduit at the top or bottom conduit
knockouts of the rack containing the feeder lugs. This is usually
the left-most rack, or if provided, the auxiliary feeder rack. See
Table IV, page 11 for knockout size and location. Dimmer racks
can also be field punched for one 3" T.S. conduit in the top, and if
provided, the auxiliary feeder rack will accept two 4" T.S. conduits
in the blower opening cover plates.
Figure 2 – Conduit Entry Area
Bottom Conduit Knockouts
• Terminate load conduits at top and/or bottom conduit knockouts
of the rack which the loads will be connected. In most cases this
means the first 24 loads should connect to the first rack, the next
24 loads should connect to the second rack and so on.
• Terminate the control conduits at the top, bottom or side conduit
knockouts of the first rack. Bottom or side access is preferable.
Step 4 - Convert Bussing To Single-Phase
Racks are shipped ready to accept three-phase, 4 wire feeders.
If feeder is single-phase, 3 wire, convert bussing as follows.
Otherwise skip to the next Step (5).
Single Rack:
•
Locate the required 1Ø Bus Adapter Kit, Model No. LEC 2012
(shipped separately).
• Remove the terminal lugs on the ØB bus and either the ØA or ØC bus. Refer to Figure 3. Keep the hardware, as it will be reused
below.
• Install one end of the jumper bus bar from the kit to the feeder bus plate mounting hole on the ØB bus. Note that the bus is installed in
front of the plate. Use the bolts kept from above noting that all bolted joints include a flat washer against all bus/lug surfaces, and a lock
washer under the nut.
• Re-install one terminal along with the other end of the jumper bus bar to the feeder bus plate mounting hole on ØA or ØC bus using
the long bolt supplied with the bus bar kit, and the balance of the hardware from above. Note that the lug is installed behind the plate,
and that the joint includes a flat washer on top of the jumper bus as well as behind the lug. (If this kit is installed in more than one rack,
connect to ØA
in the first rack and ØC in the second rack to balance feeder).
Two racks bussed together:
•
Proceed with the first (left-most) rack as above jumpering ØA to ØB and re-installing the lug on ØA.
• Install a second 10 Bus Adapter Kit in the second rack as above jumpering ØB to ØC for balance. In this rack no lugs are re-installed
and the jumpering bus must be installed on the back of the feeder bus plate in order to clear the lateral neutral bus.
Note: Do not install lateral bus between the two ØB busses. Since one ØB bus is jumpered to ØA and one is jumpered to ØC, a short
circuit will develop.
Step 5 - Pull power, load and control conductors to the racks
•
Pull all conductors into the racks. Feeder and load conductors must be rated for 90
˚
C, and be copper. Control conductors must be
rated for operation at 85
˚
C and are all Class 2. All control conductors must be routed so that they are not likely to come in contact with
feeder or load conductors.
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