Installation manual

IM-487 Page 41
Table 11: Recommended 3-phase power wiring*
*To provide that disconnects and power blocks mate with power wiring
Notes:
1. All wire sizes assume separate conduit for each set of
parallel conductors.
2. All wire sizes based on NEC Table 310-16 for THW wire (copper).
Canadian electrical code wire ampacities may vary.
3. All wire sizes assume no voltage drop for short power leads.
*To provide that disconnects and power blocks mate with power wiring.
Copper wire is required for all power lead terminations at the
unit. Size wires in accordance with the ampacity tables in
Article 310 of the National Electrical Code. If long wires are
required, it may be necessary to increase the wire size to pre-
vent excessive voltage drop. Size wires for a maximum of
3% voltage drop. Supply voltage must not vary by more than
10% of nameplate. Phase voltage imbalance must not exceed
2%. (Calculate the average voltage of the three legs. The leg
with voltage deviating the farthest from the average value
must not be more than 2% away.) Contact local power com-
pany for correction of improper voltage or phase imbalance.
A ground lug is provided in the control panel for each power
conduit. Size grounding conductor in accordance with Table
250-95 of the National Electrical Code.
In compliance with the National Electrical Code, an electri-
Cally isolated 115V circuit is provided in the unit to supply
the factory mounted service receptacle outlet and optional
unit lights. This circuit is powered by a field connected 15A
115V power supply. Leads are brought into the RAH unit
through a 7/8" knockout in the bottom of the main control
panel, near the power wire entry point.
Figure 45. Power Wiring Entrance
Figure 46. Optional Side Power Wiring Entrance
FOR MCA
Up to
(Amps)
Wire
Gauge
Qty./
Pole
Insulation
rating (°C)
No. of
Conduits
Conduit/
(Trade,
Size, In.)
30 10 1 60 1 1/2
40 8 1 60 1 3/4
55 6 1 60 1 1
70 4 1 60 1 1-1/4
85 3 1 60 1 1-1/4
95 2 1 60 1 1-1/4
130 1 1 75 1 1-1/4
150 1/0 1 75 1 1-1/2
175 2/0 1 75 1 2
200 3/0 1 75 1 2
230 4/0 1 75 1 2
255 250 1 75 1 2-1/2
285 300 1 75 1 2-1/2
310 350 1 75 1 3
335 400 1 75 1 3
380 500 1 75 1 3
400 3/0 2 75 2 2
460 4/0 2 75 2 2
510 250 2 75 2 2-1/2
570 300 2 75 2 2-1/2
620 350 2 75 2 3
670 400 2 75 2 3
760 500 2 75 2 3
765 250 3 75 3 2-1/2
855 300 3 75 3 2-1/2
930 350 3 75 3 3
CAUTION
Improper line voltage or excessive phase
imbalance constItutes product abuse. May cause
severe damage to the unit electrical components.
Assure proper line voltage and phase balance.
WARNING
Electrical shock hazard.
May cause severe injury or death.
All protective deadfront panels must be reinstalled and
secured when power wiring is complete.
Electric Heat
Control Panel
Disconnect
Switch DS3
(Optional)
Power Block PB: or
Disconnect Switch DS1
3" Knockouts for Power Wire
(Qty. 3 in Main Control Panel;
Qty. 3 in Electric Heat Control Panel)
Main
Control
Panel
Terminal Block
TB1 for 115V
Service
Receptacle
Circuit
7/8" Knockouts for 115V
Service Receptacle Circuit
NOTE:
Refer to Certified
Drawings for dimensions
to wire entry points.
3" (76mm) Max. Dia.
2.75"
(70mm)
16.00"
(406mm)
Main
Control
Box
Remove Lifting
Bracket Before
Drilling Hole