Electrical; Electrical Connections; Low- -Voltage Circuit Fusing And Reference; Ground Connections - Carrier GC Series Installation Instructions Manual

ELECTRICAL

Electrical Connections

WARNING
!
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installing or servicing unit, always turn off all power
to unit. There may be more than 1 disconnect switch. Turn
off accessory heater power if applicable.
WARNING
!
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
If a disconnect switch is to be mounted on the unit, select a
location where drill or fastener will not contact electrical or
refrigerant components.
WARNING
!
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Field wires on the line side of the disconnect remain live,
even when the pull- -out is removed. Service and maintenance
to incoming wiring can not be performed until the main
disconnect switch (remote to the unit) is turned off.
NOTE: Before proceeding with electrical connections, make
certain that supply voltage, frequency, and phase are as specified
on unit rating plate. Be sure that electrical service provided by the
utility is sufficient to handle the additional load imposed by this
equipment. See unit wiring label for proper field high- - and low- -
voltage wiring. Make all electrical connections in accordance with
NEC and any local codes or ordinances that may apply. Use copper
wire only. The unit must have a separate branch electric circuit with
a field- -supplied disconnect switch located within sight from and
readily accessible from the unit.
24- - V Control System Connections to Bus Com Harness
Field Connection
Use the field ABCD connector provided with the User Interface.
Connect this plug to the factory wired female ABCD connector on
the bus com harness (see Fig. 17). Use No. 18 AWG color- -coded,
insulated (35_C minimum) wires to make low- -voltage connections
between User Interface and unit. If User Interface is located more
than 100 ft. from unit (as measured along the low- -voltage wires),
use No. 16 AWG color- -coded, insulated (35_C minimum) wires or
in accordance with local codes.
Connect low- -voltage leads to User Interface . (See Fig. 18.)
NOTE: Where local codes require User Interface wiring be routed
through conduit or raceways, splices can be made inside blower
unit. All wiring must be NEC Class l and must be separated from
incoming power leads.

Low- -Voltage Circuit Fusing and Reference

The low- -voltage circuit is fused by a board- -mounted 3- -amp.
automotive fuse placed in series with transformer SEC1 and R
circuit. The C circuit of transformer circuit is referenced to chassis
ground through a printed circuit run at SEC2 and metal PC board
mounting eyelets. Check to be sure PC Board is mounted securely
using both factory installed screws.
NOTE: Mis- -wiring or shorting any of the low voltage
connections may cause the low voltage fuse to open but will not
damage the User Interface or ECM board. Simply rewire and
replace fuse to correct fault.

Ground Connections

WARNING
!
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
The cabinet must have an uninterrupted or unbroken ground
according to NEC, ANSI/NFPA 70 and local codes to
minimize personal injury if an electrical fault should occur.
The ground may consist of electrical wire or metal conduit
when installed in accordance with existing electrical codes.
(See Ground/Conduit Note below.)
NOTE: Use UL listed conduit and conduit connector to connect
supply wire(s) to unit and obtain proper grounding. If conduit
connection uses reducing washers, a separate ground wire must be
used. Grounding may also be accomplished by using grounding
lug provided in control box. Use of dual or multiple supply circuits
will require grounding of each circuit to ground lugs provided on
unit and heaters.
Refer to electrical component box layout. See Fig. 16.
CAUTION
!
UNIT OPERATION HAZARD
Failure to follow this caution may result in equipment
damage and/or improper operation.
SField wiring must comply with local and national electrical
codes.
SPower to the unit must be within the operating voltage range
indicated on the unit nameplate or on the performance data
sheet.
SOperation of unit on improper line voltage or with excessive
phase imbalance will be hazardous to the unit, constitutes
abuse, and may void the warranty.
Properly sized fuses or HACR circuit breakers must be installed for
branch circuit protection. See unit nameplate for maximum fuse or
breaker size.
NOTE: Use copper wire only between disconnect switch and
unit.
The unit is provided with a concentric knock- -out for attaching
common trade sizes of conduit, route power supply wiring through
this opening.
Always connect the ground lead to the grounding lug provided in
the control box and power leads to the line side of compressor
contactor as indicated on the wiring diagrams.
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