Wiring Requirements - Carrier 40MBAB Installation Instructions Manual

40MBAB: Installation Instructions

WIRING REQUIREMENTS

Size all wires per the NEC (National Electrical Code) or CEC (Canadian
Electrical Code) and local codes. Use the electrical data from the outdoor unit
(MCA - minimum circuit amps and MOCP - maximum over current protection),
to correctly size the wires and the disconnect fuse or breakers respectively.
SIZE 18 - 36K (NON LIGHT-COMMERCIAL MODELS)
RECOMMENDED CONNECTION METHOD FOR POWER
AND COMMUNICATION WIRING
Power and Communication Wiring: The main power is supplied to the
outdoor unit. The field supplied 14/3 power/communication wiring, from
the outdoor unit to the indoor unit, consists of four (4) wires and provides
the power for the indoor unit. Two wires are high voltage AC power, one
is communication wiring and the other is a ground wire.
To minimize communication interference: If installed in a high
Electromagnetic field (EMF) area and communication issues arise, a 14/2
stranded shielded cable can be used to replace L2 and (S) between the outdoor
and indoor units - landing the shield onto the ground in the outdoor unit only.
Table 12 — Wiring Sizes 12K-36K
Cable Cable Size
Connection Cable 14AWG
SIZES 36-60 (LIGHT-COMMERCIAL MODELS)
RECOMMENDED CONNECTION METHOD FOR POWER
AND COMMUNICATION WIRING
Power and Communication Wiring: The main power is supplied to the
outdoor unit. The field supplied power wiring from the outdoor unit to the
indoor unit consists of three (3) wires and provides the power for the
indoor unit. Two wires are high voltage AC power and one is a ground
wire. To minimize voltage drop, the factory recommended wire size is 14/
2 power stranded with a ground.
Communication Wiring: A separate 2-wire cable (stranded, shielded,
copper conductor), with a 600 volt rating and double insulated copper
wire, must be used as the communication wire from the outdoor unit to
the indoor unit. Use a separate shielded 16AWG stranded control wire.
Table 13 — Wiring Sizes 36K-60K
Cable Cable Size
Power Connection Cable 14AWG
Communication Cable 16AWG
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Remarks
Φ
3 wire + Ground 1 208/230 V
(Stranded wire is required)
Remarks
Φ
2 wire + Ground 1 208/230 V
2 wire stranded shielded control wire
CAUTION
EQUIPMENT DAMAGE HAZARD
Be sure to comply with local codes while running wire from the
indoor unit to the outdoor unit.
Every wire must be connected firmly. Loose wiring may cause the
terminal to overheat or result in a unit malfunction. A fire hazard
may also exist. Ensure all wiring is tightly connected.
No wire should touch the refrigerant tubing, compressor or any
moving parts.
Disconnecting means must be provided and located within sight
and readily accessible from the system. Route the connecting
cable with conduit through the hole in the conduit panel.
NOTE: The main power is supplied to the outdoor unit. When
disconnecting the power of the outdoor unit, the indoor unit
would lose power. A disconnect switch is not required on the
Indoor unit side on the wiring between the Outdoor and
Indoor unit. A 3 pole disconnect may be used for extra
protection between the indoor and outdoor unit (refer to
local codes). A separate power source is required for an
auxiliary electric heater.
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