Carrier WeatherMaker 50TCQ*08, Руководство по установке

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26
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.
This amount of phase imbalance is satisfactory as it is below the maxi-
mum allowable 2%.
NOTE: Check all factory and field electrical connections for
tightness.
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 stand alone control) or the RTU Open
Controller for Building Management Systems using non-CCN
protocols. (RTU Open is available as a factory-installed option
only.)
THERMOSTAT
Install a Carrier-approved accessory 2 stage Cooling/Heating
thermostat according to installation instructions included with
the accessory. The 50TCQ models do not require a thermostat
with an O function to control the reversing valve operation. If
using an electronic thermostat, configure it for “non-heat
pump” operation. 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 ther-
mostat 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 [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.
Fig. 37 — Typical Low-Voltage Control Connections
Central Terminal Board
The Central Terminal Board (CTB) is a pass through connec-
tion point. The CTB provides the capability to add factory-in-
stalled options and field-installed accessories to the units by
cutting jumper wires without having to change or reroute wires
through the structure of the unit. The CTB does not provide
any microprocessor control; it is simply a basic multifunction
wiring terminal configuration.
Commercial Defrost Control
The Commercial Defrost Control Board (DFB) coordinates
thermostat demands for supply fan control, 1 or 2 stage cool-
ing, 2 stage heating, emergency heating and defrost control
with unit operating sequences. The DFB also provides an in-
door fan off delay feature (user selectable). See Fig. 38 for
board arrangement.
% Voltage Imbalance = 100x
4
= 1.78%
227
IMPORTANT: If the supply voltage phase imbalance is more
than 2%, contact your local electric utility company
immediately.
X
C
G
W2
C
W2
G
W1
O/B/Y2
Y2
R
W1
R
Y1 Y1
T
H
E
R
M
O
S
T
A
T
(Note 1)
(Note 2)
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
Centr a l
Termin a l
Bo a rd
Typic a l
Thermo s t a t
Connection s