Hacr; Units Without Thru-Base Connections; Thermostat - Carrier WeatherExpert 48LC 04 Series Installation Instructions Manual

receptacle does not trip as required. Press the RESET button to
clear the tripped condition.

HACR

The amp rating of the HACR factory-installed option is based
on the size, voltage, indoor motor, and other electrical options
of the unit as shipped from the factory. If field-installed acces-
sories are added or changed in the field (i.e. electric heat, pow-
er exhaust, ERV), the HACR may no longer be of the proper
amp rating and therefore will need to be removed from the
unit. See unit nameplate and label on factory-installed HACR
for the amp rating of the HACR that was shipped with the unit
from the factory. See unit nameplates for the proper fuse,
HACR, or maximum over-current protection device required
on the unit with field-installed accessories. See Fig. 43.
Fig. 43 — HACR Caution Label
FACTORY-OPTION THRU-BASE CONNECTIONS (ELEC-
TRICAL CONNECTIONS)
This service connection kit consists of a
er fitting (brass), a 1 / -in. electrical bulkhead connector and a
2
3 / -in. electrical bulkhead connector, all factory-installed in the
4
embossed (raised) section of the unit basepan in the condenser
section. The 3 / -in. bulkhead connector enables the low-voltage
4
control wires to pass through the basepan. The
bulkhead connector allows the high-voltage power wires to
pass through the basepan. See Fig. 21.
Check tightness of connector lock nuts before connecting elec-
trical conduits.
Field-supplied and field-installed liquid-tight conduit connec-
tors and conduit may be attached to the connectors on the base-
pan. Pull correctly-rated high voltage and low voltage through
appropriate conduits. Connect the power conduit to the internal
disconnect (if unit is so equipped) or to the external disconnect
(through unit side panel). A hole must be field-cut in the main
control box bottom on the left side so the 24-v control connec-
tions can be made. Connect the control power conduit to the
unit control box at this hole.

UNITS WITHOUT THRU-BASE CONNECTIONS

1. Install power wiring conduit through side panel openings.
Install conduit between disconnect and control box.
2. Install power lines to terminal connections as shown in
Fig. 29.
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. On 3-phase
units, voltages between phases must be balanced within 2%
1 / -in. NPT gas adapt-
2
1 / -in. electrical
2
26
and the current within 10%. Use the following formula to de-
termine the percent of voltage imbalance. Operation on im-
proper line voltage or excessive phase imbalance constitutes
abuse and may cause damage to electrical components. Such
operation would invalidate any applicable Carrier warranty.
% Voltage Imbalance:
max voltage deviation from average voltage
= 100 x
Example: Supply voltage is 230-3-60
A B C
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
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.
FIELD CONTROL WIRING
The 48LC unit requires an external-temperature control device.
This device can be a thermostat (field-supplied) or, the RTU
Open Controller for Building Management Systems using non-
CCN protocols (RTU Open is available as a factory-installed
option only), or a space temperature sensor (SPT) with factory
installed SystemVu™ controller.

THERMOSTAT

Install a Carrier-approved accessory thermostat according to
installation instructions included with the accessory. For com-
plete economizer function and two-stage compressor opera-
tion, select a two-stage cooling thermostat. Locate the thermo-
stat accessory on a solid wall in the conditioned space to sense
average temperature in accordance with the thermostat installa-
tion instructions.
If the thermostat contains a logic circuit requiring 24-v power,
use a thermostat cable or equivalent single leads of different
colors with minimum of seven leads. If the thermostat does not
require a 24-v source (no "C" connection required), use a ther-
mostat cable or equivalent with minimum of six leads. Check
the thermostat installation instructions for additional features
which might require additional conductors in the cable.
For wire runs up to 50 ft. (15 m), use no. 18 AWG (American
Wire Gage) insulated wire [35°C (95°F) minimum]. For 50 to
75 ft. (15 to 23 m), use no. 16 AWG insulated wire [35°C
(95°F) minimum]. For over 75 ft. (23 m), use no. 14 AWG in-
sulated wire [35°C (95°F) minimum]. All wire sizes larger than
no. 18 AWG cannot be directly connected to the thermostat and
will require a junction box and splice at the thermostat. See
Fig. 44.
average voltage
AB = 224 v
BC = 231 v
AC = 226 v
681
= = 227
3 3
4
= 1.78%
227