Table of Contents
Advertisement
Electric
Disconnect
Switch
Fig. 8 — Disconnect Switch and Unit
UNITS WITHOUT FACTORY-INSTALLED DISCONNECT
When installing units, provide a disconnect switch per NEC (Na-
tional Electrical Code) of adequate size. Disconnect sizing data is
provided on the unit informative plate. Locate on unit cabinet or
within sight of the unit per national or local codes. Do not cover
unit informative plate if mounting the disconnect on the unit
cabinet.
UNITS WITH FACTORY-INSTALLED DISCONNECT
The factory-installed option disconnect switch is located in a
weatherproof enclosure located under the main control box. The
manual switch handle is accessible through an opening in the
access panel.
ALL UNITS
All field wiring must comply with NEC and all local codes. Size
wire based on MCA (Minimum Circuit Amps) on the unit infor-
mative plate. See Fig. 9 for power wiring connections to the unit
power terminal block and equipment ground. Maximum wire size
is no.4 ga AWG per pole.
Provide a ground-fault and short-circuit over-current protection
device (fuse or breaker) per NEC Article 440 (or local codes). Re-
fer to unit informative data plate for MOCP (Maximum Overcur-
rent Protection) device size.
All field wiring must comply with the NEC and local
requirements.
Units Without Disconnect Option
11
L1
Units With Disconnect Option
L1
2
L2
4
L3
6
Disconnect factory test leads; discard.
Fig. 9 — Power Wiring Connections
Copper
Wire Only
Aluminum
Wire
C
TB1
13
Disconnect
per
NEC
L2
L3
208/230-3-60
460-3-60
575-3-60
1
Optional
Factory
Disconnect
3
Wiring
Switch
5
VOLTAGE AND CURRENT BALANCE
Voltage to compressor terminals during operation must be within
voltage range indicated on unit nameplate. See Table 9. On
3-phase units, voltages between phases must be balanced within
2% and the current within 10%. Use the formula shown in the
legend for Table 9, Note a (see page 16) to determine the percent
of voltage imbalance. Operation on improper line voltage or ex-
cessive phase imbalance constitutes abuse and may cause damage
to electrical components. Such operation would invalidate any ap-
plicable Carrier warranty.
Convenience Outlets
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury or
death.
Units with convenience outlet circuits may use multiple
disconnects. Check convenience outlet for power status before
opening unit for service. Locate its disconnect switch, if
appropriate, and open it. Tag-out this switch, if necessary.
Two types of convenience outlets are offered on 38AUQ models:
Non-powered and unit-powered. Both types provide a 125-volt
GFCI (ground-fault circuit-interrupter) duplex receptacle rated at
15-A behind a hinged waterproof access cover, located on the end
panel of the unit. See Fig. 10.
Convenience
Outlet
GFCI
Pwd-CO
Fuse
Switch
Control Box
Access Panel
Fig. 10 — Convenience Outlet Location
Non-powered type: This type requires the field installation of a
general-purpose 125-volt 15-A circuit powered from a source
elsewhere in the building. Observe national and local codes when
selecting wire size, fuse or breaker requirements and disconnect
switch size and location. Route 125-v power supply conductors
into the bottom of the utility box containing the duplex receptacle.
Unit-powered type: A unit-mounted transformer is factory-
installed to stepdown the main power supply voltage to the unit to
115-v at the duplex receptacle. This option also includes a manual
switch with fuse, located in a utility box and mounted on a bracket
behind the convenience outlet; access is through the unit's control
box access panel. See Fig. 10.
13
WARNING
Pwd-CO
Transformer
Advertisement
Table of Contents
