Carrier 50KC04, Руководство по установке

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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. 21.
Voltage to compressor terminals during operation must be within
voltage range indicated on unit nameplate. On 3-phase units, volt -
ages between phases must be balanced within 2% and the current
within 10%. Use the formula shown below to determine the per -
cent of voltage imbalance. Operation on improper line voltage or
excessive phase imbalance constitutes abuse and may cause dam -
age to electrical components. Such operation would invalidate any
applicable Carrier warranty.
Example: Supply voltage is 230-3-60
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%.
FIELD CONTROL WIRING
The 50KC 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 Open Controller for Building Manage -
ment Systems using non-CCN protocols (RTU Open is available
as a factory-installed option only).
THERMOSTAT
Select a Carrier-approved accessory thermostat. When electric
heat is installed in the 50KC unit, the thermostat must be capable
of energizing the G terminal (to energize the Indoor Fan Contac -
tor) whenever there is a space call for heat (energizing the W1 ter -
minal). The accessory thermostats listed on the unit price pages
can provide this signal but they are not configured to enable this
signal as shipped.
Install the accessory thermostat according to installation instruc -
tions included with the accessory.
Locate the thermostat accessory on a solid wall in the conditioned
space to sense average temperature in accordance with the ther -
mostat 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 in -
stallation 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 insulated
wire [35°C (95°F) minimum]. All wire sizes larger than no. 18
AWG cannot be directly connected to the thermostat and will re -
quire a junction box and splice at the thermostat.
Fig. 32 — Low-Voltage Connections
UNIT WITHOUT THRU-BASE CONNECTION KIT
Pass the thermostat control wires through the hole provided in the
corner post; then feed the wires through the raceway built into the
corner post to the control box. Pull the wires over to the terminal
strip on the upper-left corner of the Controls Connection Board.
See Fig. 33.
NOTE: If thru-the-bottom connections accessory is used, refer to
the accessory installation instructions for information on routing
power and control wiring.
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.
Fig. 33 — Field Control Wiring Raceway
% Voltage
Imbalance
= 100 x
max voltage deviation from average voltage
average voltage
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
= 227
3 3
% 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.
A B C
MOTOR
X
C
G
W2
R
C
W2
G
W1
O/B/Y2
Y2
W1
R
Y1 Y1
Typical
Thermostat
Connections
T
H
E
R
M
O
S
T
A
T
(Note 1)
(Note 2)
(Note 3)
1. Typical multi-function marking. Follow manufacturer’s configuration
instructions to select Y2.
2. Y2 to Y2 connection required on single-stage cooling units when
integrated economizer function is desired
3. W2 connection not required on units with single-stage heating.
Field Wiring
Central
Terminal
Board
Notes:
RACEWAY
HOLE IN END PANEL (HIDDEN)