Carrier 50TCQD Installation Instructions Manual page 16

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
FNQ- - 7 dual element time delay fuse.
Using unit- - mounted convenience outlets: Units with
unit- - mounded 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 —
All units are equipped with the ability to bring utilities
through the base.
The electrical entrance is located in the control box area
can can be accessed through the control box access panel.
An embossed area is provided with three knock outs. High
voltage is brought through the multi knock out by
removing the appropriate size for the size of the fitting
7
required. A / - - in. knock out is provided for low voltage.
8
7
An additional / - - in. knock out is provided for a 115 volt
8
line which is used when the unit is equipped with the
non- - powered convenience outlet option.
All required fittings are field supplied. Install fittings
when access to both top and bottom of the base pan is
available.
Units without Thru- - Base Connections —
1. Install conduit, liquid tight, between disconnect and
control box.
2. Pull correctly rated high voltage wires through the
conduit.
3. Install power lines to terminal connections as shown
in Fig. 17.
All Units —
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 following
formula to determine the percent of voltage imbalance.
max voltage deviation from average voltage
% Voltage Imbalance = 100 x
Operation on improper line voltage or excessive phase
imbalance constitutes abuse and may cause damage to
electrical components. Such operation would invalidate
any applicable Carrier warranty.
Field Control Wiring —
The 50TCQD unit requires an external temperature
control device. This device can be a thermostat
(field- - supplied) or a PremierLink controller (available as
factory- - installed option or as field- - installed accessory, for
use on a Carrier Comfort Network or as a stand alone
average voltage
C09103
control) or the RTU- - MP Controller for Building
Management Systems
(RTU- - MP is available as a factory- - installed option only).
Thermostat —
Install a Carrier- - approved accessory thermostat according
to installation instructions included with the accessory.
For complete economizer function, select a two- - stage
cooling thermostat. Locate the thermostat accessory on a
solid wall in the conditioned space to sense average
temperature in accordance with the thermostat installation
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 thermostat 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 minimum).
For 50 to 75 ft. (15 to 23 m), use no. 16 AWG insulated
wire (35_C minimum). For over 75 ft. (23 m), use no. 14
AWG insulated wire (35_C 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.
Typical
Thermostat
Corrections
C
G
W2
(Note 3)
W1
O/B/Y2
(Note 2)
(Note 1)
Y1
R
Note 1: Typical multi-function marking. Follow manufacturer's configuration
instructions to select Y2.
Note 2: Y2 to Y2 connection required on single-stage cooling units when
integrated economizer function is desired
Note 3: W2 connection not required on units with single-stage heating.
Field Wiring
Fig. 21 - - Typical Low- - Voltage Control Connections
Unit without thru- - base connection —
Correctly rated low voltage wire can be routed through the
rubber grommet located on the corner post adjacent to the
control box access panel. Route wire through the grommet
16
using non- - CCN protocols
Central
Terminal
Board
X X
C C
G G
W2 W2
W1 W1
Y2 Y2
Y1 Y1
R
R
T–STAT
C09257