Units Without Thru-Base Connections; Field Control Wiring; Thermostat - Carrier WeatherMaker 50TCQ07 Installation Instructions Manual

allows the high-voltage power wires to pass through the base-
pan. See Fig. 30.
Fig. 30 — Thru-Base Connection Fittings
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 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. 20.
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%
and the current within 10%. Use the formula below to deter-
mine the percent of voltage imbalance. Operation on improper
line voltage or excessive phase imbalance constitutes abuse
and may cause damage to electrical components. Such opera-
tion would invalidate any applicable Carrier warranty.
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.
LOW VOLTAGE
CONDUIT
CONNECTOR
HIGH VOLTAGE
CONDUIT
CONNECTOR
AB = 224 v
BC = 231 v
AC = 226 v
681
= = 227
3 3
4
= 1.78%
227

FIELD CONTROL WIRING

The 50TCQ unit requires an external temperature control de-
vice. This device can be a thermostat (field-supplied) or a Pre-
mierLink™ controller (available as factory-installed option or
as field-installed accessory, for use on a Carrier Comfort Net-
work system or as a standalone control) or the RTU Open
®
Controller for Building Management Systems using non-CCN
protocols (RTU Open controller is available as a factory-in-
stalled option only).

THERMOSTAT

Select a Carrier-approved accessory thermostat. When electric
heat is installed in the 50TCQ unit, the thermostat must be ca-
pable of energizing the G terminal (to energize the Indoor Fan
Contactor) whenever there is a space call for heat (energizing
the W1 terminal). The accessory thermostats listed on the unit
price pages can provide this signal but they are not configured
to enable this signal as shipped.
Typical
Thermostat
Connections
C
G
W2
(Note 2)
W1
O/B/Y2
(Note 1)
Y1
R
Note 1: Typical multi-function marking. Follow manufacturer's configuration
instructions to select Y2. Do not configure for O output.
Note 2: W2 connection not required on units without electric heating.
Field Wiring
Fig. 31 — Low-Voltage Connections
Install the accessory thermostat according to installation in-
structions included with the accessory.
Locate the thermostat accessory on a solid wall in the condi-
tioned space to sense average temperature in accordance with
the thermostat installation instructions. If the thermostat con-
tains a logic circuit requiring 24-v power, use a thermostat ca-
ble 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 cable or equiva-
lent with minimum of six leads. Check the thermostat installa-
tion 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.
19
Central
Terminal
Board
X
C
T
H
G
E
R
W2
M
O
W1
S
T
Y2
A
T
Y1
R