Wiring Requirements - Carrier 40MBAA Installation Instructions Manual

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 24 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 10 — Wiring Size 24
CABLE CABLE SIZE
Connection
14AWG
Cable
SIZES 36-48 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.
Please use a separate shielded 16AWG stranded control wire.
IM-40MBAA-02
REMARKS
Φ
3 wire + Ground 1 208/230 V
(Stranded wire is recommended)
Specifications subject to change without notice.
Table 11 — Wiring Sizes 36-48
CABLE CABLE SIZE
Power
Connection 14AWG
Cable
Communication
16AWG
Cable
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: T
he 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. A separate power is
required for an Auxiliary Electric Heater.
REMARKS
Φ
2 wire + Ground 1 208/230 V
2 wire stranded shielded control
wire
17