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56
VCCX2 Controller Technical Guide
18-30 VAC
GND
Line
Voltage
Size transformer for
correct total load.
RSMD = 18 VA
RSMD
REVERSING VALVE
COMPRESSOR 2 ENABLE
COMPRESSOR 1 ENABLE
24 VAC ONLY
CONDENSER 1 ENABLE
10A250V
A
C
~
5
A
3
0
V
D
C
SA
VDE
G5Q-1A
4
O
M
R
O
N
D
C
1
2
V
C
H
IN
A
CONDENSER 2 ENABLE
DIGITAL
COMPRESSOR 1
+
GND
DIGITAL
COMPRESSOR 2
COM
+
CONDENSER
SIGNAL 1
Connects to VCCX2
loop communications
connector when used
an a split system.
Connect to
VCCX2 Controller
CONDENSER
SIGNAL 2
3 Y1
2 +
1 COM
WSE BYPASS
VALVE ACTUATOR
Belimo Actuator wiring
shown. Consult factory
for other manufacturer
wiring instructions
COM
+
+
GND
Note:
All relay outputs are normally
open and rated for 24 VAC
power only.
1 amp maximum load.
Figure 37: RSMD Outputs Wiring
Head Pressure Control
The Head Pressure Transducers are used to measure Head
Pressure at the discharge line. This Head Pressure is used to drive
the condenser fans with a 0-10 VDC output signal to maintain a
given Head Pressure Setpoint.
Compressor Discharge Sensors
The Digital Compressor Discharge Temperature Sensor monitors
the discharge temperature from the Digital Compressor to protect
against overheating.
Leaving Water Temperature Sensor
The Leaving Water Temperature Sensor is used to measure the
Leaving Water Temperature when used on a WSHP unit.
CAUTION:
The Shraeder port used for installation of the
suction pressure transducer should be located
in a vertical position of the suction line to
prevent refrigerant oil from accumulating in
the sensor.
NOTE:
If there are two compressors on a single circuit (a
tandem circuit), Suction Pressure 2, Head Pressure
2, and Condenser Signal 2 would not be used.
WIRING
RSMD Outputs