All Units; Convenience Outlets - Carrier WeatherExpert 48LC Series Installation Instructions Manual

14-26 single package rooftop gas heat/electric cooling unit with puron (r-410a) refrigerant
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ALL UNITS

All field wiring must comply with NEC and all local code
requirements.
Size wire based on MCA (Minimum Circuit Amps) on the unit in-
formative plate. See Fig. 45 for power wiring connections to the
unit power terminal block and equipment ground. Maximum wire
size is 2/0 AWG per pole.
Units Without Disconnect or HACR Option
TB1
11
Disconnect
L1
208/230-3-60
460-3-60
575-3-60
Units With Disconnect or HACR Option
Factory
Wiring
T1
L1
L1
Fig. 45 — Power Wiring Connections
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 Over-cur-
rent Protection) device size.
NOTE: Units ordered with factory-installed HACR do not need
additional ground-fault and short circuit over current protection
device unless required by local codes.
Voltage to compressor terminals during operation must be within
voltage range indicated on unit nameplate. On 3-phase units, volt-
ages between phases must be balanced within 2% and the current
within 10%. Use the formula shown below to determine the per-
cent of voltage imbalance.
% Voltage Imbalance:
max voltage deviation from average voltage
= 100 x
average voltage
Example: Supply voltage is 230-3-60
AB = 224 v
A
B
C
BC = 231 v
AC = 226 v
MOTOR
(224 + 231 + 226)
Average Voltage
=
Determine maximum deviation from average voltage.
(AB) 227-224 = 3 v
(BC) 231-227 = 4 v
(AC) 227-226 = 1 v
Equip
12
13
GR Lug
per NEC
L2
L3
Ground
(GR)
Equip
GR Lug
T2
T3
Optional
Disconnect
Switch
or HACR
L2
L3
Ground
L2
L3
(GR)
681
=
= 227
3
3
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100x
This amount of phase imbalance is satisfactory as it is below the maxi-
mum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than 2%,
contact your local electric utility company immediately.
NOTE: Check all factory and field electrical connections for tightness.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Operation on improper line voltage or excessive phase imbal-
ance constitutes abuse and may cause damage to electrical
components. Such operation would invalidate any applicable
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. Lock-out and tag-out this switch, if
necessary.
Two types of convenience outlets are offered on 48LC models:
non-unit powered and unit-powered. Both types provide a 125-v
GFCI (ground-fault circuit-interrupter) duplex receptacle rated at
15-A behind a hinged access cover, located on the corner panel of
the unit. See Fig. 46.
CONTROL BOX
ACCESS PANEL
ELECTRIC
DISCONNECT
SWITCH
CONVENIENCE
OUTLET
Fig. 46 — Convenience Outlet Location
Installing Weatherproof Cover
A weatherproof while-in-use cover for the factory-installed conve-
nience outlets is now required by UL standards. This cover cannot
be factory-mounted due to its depth; it must be installed at unit in-
stallation. For shipment, the convenience outlet is covered with a
blank cover plate.
The weatherproof cover kit is shipped in the unit's control box.
The kit includes the hinged cover, a backing plate and gasket.
DISCONNECT ALL POWER TO UNIT AND CONVE-
NIENCE OUTLET. LOCK-OUT AND TAG-OUT ALL
POWER.
36
4
= 1.78%
227
CAUTION
WARNING

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