Carrier 50TC*D17 Series, Installation Instructions Manual

Page: 14 / 36

50TC
*D
14
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
and 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
required. A 22 mm (
7
/
8
--in.) knock out is provided for low
voltage.
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.
% Voltage Imbalance = 100 x
max voltage deviation from average voltage
average voltage
C09103
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 50TC*D 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 control) or the
RTU--MP Controller for Building Management Systems
using non--CCN protocols (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 15 m (50 ft.), use no. 18 AWG
(American Wire Gage) insulated wire (35
_
C minimum).
For 15 to 23 m (50 to 75 ft.), use no. 16 AWG insulated
wire (35
_
C minimum). For over 23 m (75 ft.), 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
Central
Terminal
Board
W1
Y2
Y1
R
W2
G
C
X
W1
Y2
Y1
R
W2
G
C
X
T–STAT
C
W2
G
W1
O/B/Y2
R
Y1
(Note 1)
(Note 2)
(Note 3)
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
C09257
Fig. 18 -- 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
and then route the wire behind the corner post utilizing the
factory provided wire ties secured to the control box. This
will insure separation of the field low voltage wire and the
high voltage circuit. Route the low voltage wire to the
central terminal board. See Fig. 19.
NOTE : If utilizing the through the base connections,
route the low voltage wire through the wire ties to the
central terminal board.
Heat Anticipator Settings —
Set heat anticipator settings at 0.14 amp for the first stage
and 0.14 amp for second--stage heating, when available.