Carrier WeatherMaker 48TC 04, Installation Instructions Manual

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selecting wire size, fuse or breaker requirements and discon-
nect switch size and location. Route 125-v power supply con-
ductors into the bottom of the utility box containing the duplex
receptacle.
Unit-powered type — A unit-mounted transformer which is
factory-installed to step-down 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. 27.
The primary leads to the convenience outlet transformer are
not factory-connected. Selection of primary power source is a
customer-option. If local codes permit, the transformer primary
leads can be connected at the line-side terminals on the unit-
mounted non-fused disconnect or HACR breaker switch; this
will provide service power to the unit when the unit disconnect
switch or HACR switch is open. Other connection methods
will result in the convenience outlet circuit being de-energized
when the unit disconnect or HACR switch is open. See Fig. 30.
Fig. 30 — Powered Convenience Outlet Wiring
Test the GFCI receptacle by pressing the TEST button on
the face of the receptacle to trip and open the receptacle. Check
for proper grounding wires and power line phasing if the GFCI
receptacle does not trip as required. Press the RESET button to
clear the tripped condition.
Fuse on power type — The factory fuse is a Bussman “Fuse-
tron” 1 T-15, non-renewable screw-in (Edison base) type plug
fuse.
Test the GFCI receptacle by pressing the TEST button on
the face of the receptacle to trip and open the receptacle. Check
for proper grounding wires and power line phasing if the GFCI
receptacle does not trip as required. Press the RESET button to
clear the tripped condition.
Using unit-mounted convenience outlets: Units with unit-
mounted convenience outlet circuits will often require that two
disconnects be opened to de-energize all power to the unit.
Treat all units as electrically energized until the convenience
outlet power is also checked and de-energization is confirmed.
Observe National Electrical Code Article 210, Branch Circuits,
for use of convenience outlets.
FACTORY-OPTION THRU-BASE CONNECTIONS
(ELECTRICAL CONNECTIONS) — This service connec-
tion kit consists of a 1 /
2
-in. electrical bulkhead connector and a
1 1 /
4
-in. electrical bulkhead connector, all factory-installed in
the embossed (raised) section of the unit basepan in the con-
denser section. The 1 /
2
-in. bulkhead connector enables the low-
voltage control wires to pass through the basepan. The 1 1 /
4
-in.
electrical bulkhead connector allows the high-voltage power
wires to pass through the basepan. See Fig. 31.
Check tightness of connector lock nuts before connecting
electrical conduits.
Field-supplied and field-installed liquid tight conduit con-
nectors and conduit may be attached to the connectors on the
basepan. 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
connections 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 open-
ings. Install conduit between disconnect and control
box.
2. Install power lines to terminal connections as shown in
Fig. 23.
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. See Tables 7
and 8. On 3-phase units, voltages between phases must be bal-
anced within 2% and the current within 10%. Use the formula
shown in the legend for Tables 7 and 8 to determine the percent
of voltage imbalance. Operation on improper line voltage or
excessive phase imbalance constitutes abuse and may cause
damage to electrical components. Such operation would invali-
date any applicable Carrier warranty.
Field Control Wiring — The 48TC unit requires an external
temperature control device. This device can be a thermostat
(field-supplied) or a PremierLink controller (available as facto-
ry-installed option or as field-installed accessory, for use on a
Carrier Comfort Network ® or as a stand alone control) or the
RTU Open Controller for Building Management Systems us-
ing non-CCN protocols (RTU Open is available as a
factory-installed option only).
Thermostat — Install a Carrier-approved accessory 2-stage
thermostat according to installation instructions included with
the accessory. Locate the thermostat accessory on a solid wall
in the conditioned space to sense average temperature in accor-
dance with the thermostat installation instructions. If the ther-
mostat contains a logic circuit requiring 24-v power, use a ther-
mostat 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 thermostat ca-
ble or equivalent with minimum of six leads. Check the ther-
mostat 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) in-
sulated 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 insulated wire [35°C
(95°F) minimum]. All wire sizes larger than no. 18 AWG can-
not be directly connected to the thermostat and will require a
junction box and splice at the thermostat.
1. Bussmann and Fusetron are trademarks of Cooper
Technologies Company.
UNIT
VOLTAGE
CONNECT
AS
PRIMARY
CONNECTIONS
TRANSFORMER
TERMINALS
208, 230 240
L1: RED+YEL
L2: BLU+YEL H1+H3
H2+H4
460 480
L1: RED
Splice BLU+YEL
L2: GRA H1
H2+H3
H4
575 600
L1: RED
L2: GRA H1
H2