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7
Step 5 — Make Electrical Connections
FIELD POWER SUPPLY — All units except 208/230-v
units are factory wired for the voltage shown on the nameplate.
If the 208/230-v unit is to be connected to a 208-v power sup-
ply, the transformer must be rewired by moving the black wire
from the 230-v terminal on the transformer and connecting it to
the 200-v terminal from the transformer.
Refer to unit label diagram for additional information. Pig-
tails are provided for field wire connections.
When installing units, provide a disconnect per NEC. Use
copper conductors only when splice connectors are used.
NOTE: When accessory thru-the-bottom connections are used,
refer to the accessory installation instructions for information
on power wiring. Refer to Fig. 7 for drilling locations.
All field wiring must comply with NEC and local require-
ments. In Canada, electrical connections must be in accordance
with CSA (Canadian Standards Association) C22.1 Canadian
Electrical Code Part One.
Install field wiring as follows (see Fig. 8, 9, and 10):
1. Install conduit through side panel openings between dis-
connect and single point box (see Fig. 9 and 10).
2. Install power wires to terminal connections as shown in
Fig. 8.
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate (see Table 2).
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 2, Note 2 to determine the percentage of
voltage imbalance. Operation on improper line voltage or ex-
cessive phase imbalance constitutes abuse and may cause dam-
age to electrical components. (Such operation would invalidate
any applicable Carrier warranty.)
FIELD CONTROL WIRING — Install a Carrier-approved
accessory thermostat assembly according to installation
instructions included with the accessory. Locate thermostat
assembly on a solid wall in the conditioned space to sense aver-
age temperature in accordance with thermostat installation
instructions.
Route thermostat cable or equivalent single leads of colored
wire from subbase terminals to low-voltage connections on
unit (shown in Fig. 11) as described in Steps 1-5 below.
NOTE: For wire runs up to 50 ft, use no. 18 AWG (American
Wire Gage) insulated wire (35 C minimum). For 50 to 75 ft,
use no. 16 AWG insulated wire (35 C minimum). For over
75 ft, use no. 14 AWG insulated wire (35 C minimum). All
wire larger than no. 18 AWG cannot be directly connected to
the thermostat and will require a junction box and splice at the
thermostat.
1. If unit is mounted on roof curb and accessory thru-the-
bottom connection is used, route wire through connector
provided in accessory kit through the unit basepan.
2. Pass control wires through the hole provided on unit (see
connection D, Connection Sizes Table, Fig. 7).
3. Feed wire through the raceway built into the corner post
to the 24-v barrier located on the left side of the control
box. See Fig. 12. The raceway provides the UL-required
(Underwriters’ Laboratories) clearance between the high-
and low-voltage wiring.
4. Connect thermostat wires to screw terminals of low-
voltage terminal board.
5. If unit is to be equipped with electric resistance heat, en-
sure thermostat on a call for heat “W” energizes “G” out-
put. This allows fan operation on a call for heat.
Unit cabinet must have an uninterrupted, unbroken electri-
cal ground to minimize the possibility of personal injury if
an electrical fault should occur. This ground may consist of
electrical wire connected to unit ground lug in control com-
partment, or conduit approved for electrical ground when
installed in accordance with NEC (National Electrical
Code), ANSI/NFPA (American National Standards Insti-
tute/National Fire Protection Association), latest edition,
and local electrical codes. Failure to follow this warning
could result in the installer being liable for personal injury
of others.
LEGEND
Fig. 8 — Power Wiring Connections
C
— Contactor
Terminal Block
Connection
COMP(S) — Compressor(s)
IFC
— Indoor (Evaporator)
Fan Contactor
Splice Connection
NEC
— National Electrical
Code
Field Wiring
TB
— Terminal Block
Factory Wiring
50TFF008-014, 575-3-60
50TFF008-012, 208/230-3-60; 50TFF008-014, 460-3-60
50TFF014, 208/230-3-60
Summary of Contents for 50TFF008-014
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