
10
RSMD-CM Technical Guide
INPUTS AND OUTPUTS
Inputs/Outputs Map
Inputs/Outputs Map
See
Table 2, this page,
for the RSMD-CM inputs and outputs
.
Table 2: RSMD-CM Inputs and Outputs
REFRIGERATION SYSTEM MODULE
FOR DIGITAL COMPRESSORS
Analog Inputs
1
Suction Pressure 1 (SP-1)
2
Head Pressure 1 (HP-1)
3
Suction Pressure 2 (SP-2)
4
Head Pressure 2 (HP-2)
5
Compressor Discharge Temperature 1 Sensor (TEMP1)
6
Compressor Discharge Temperature 2 Sensor (TEMP2)
7
Leaving Water Temperature Sensor (TEMP3)
Binary Inputs
1
Compressor Status 1 (BI1)
2
Compressor Status 2 (BI2)
3
Outdoor Coil Temperature / Proof of Water Flow (BI3)
4
Emergency Shutdown (BI4)
Analog Outputs
1
Condenser 1 Signal (AO1)
2
Condenser 2 Fan Signal (0-10 VDC) or WSE Bypass
Actuator (2-10 VDC) (AO2)
Relay Outputs (24 VAC)
1
Compressor 1 Enable Relay (RLY1)
2
Compressor 2 Enable Relay (RLY2)
3
Condenser 1 Enable Relay (RLY3)
4
Condenser 2 Enable Relay (RLY4)
5
Reversing Valve Relay (RLY5)
NOTE:
AO1 Fan is 0-10 VDC and water valve is 2-10 VDC.
Inputs and Outputs
+5V - VDC Power
This output is a 5 VDC output that supplies power to the Suction
Pressure Transducers.
SP-1 and SP-2 - Suction Pressure Transducers
The Suction Pressure Transducers are used to measure suction
pressure at the HVAC unit’s DX evaporator coil suction line.
This suction line pressure is converted to saturated refrigerant
temperature. The saturated refrigerant temperature is used to
properly control the compressors to maintain a given Suction
Coil (Saturated) Temperature Setpoint. In Cooling Mode,
the VCCX2 resets the Suction Coil (Saturated) Temperature
Setpoint to maintain a given Supply Air Temperature Setpoint.
In Dehumidification Mode, the Suction Coil (Saturated)
Temperature Setpoint is a user configurable setpoint that can be
reset based on indoor humidity levels.
+5V - VDC Power
This output is a 5 VDC output that supplies power to the Head
Pressure Transducers.
HP-1 and HP-2 - Head Pressure Transducers
The Head Pressure Transducers are used to measure Head
Pressure at the discharge line. This Head Pressure is used to drive
the condenser fans to maintain a given Head Pressure Setpoint.
TEMP1 and TEMP2 - Compressor Discharge
Temperature Sensor 1 and Sensor 2 Input
The Digital Compressor Discharge Temperature Sensors monitor
the discharge temperature from the digital compressor to protect
against overheating.
TEMP3 - Leaving Water Temperature Sensor Input
This input monitors the condenser leaving water temperature
and determines if the water source condenser is operating in a
safe water temperature range.
BI1 - Compressor Status 1
When this wet contact input closes, a 24 volt signal to BI1
indicates Compressor 1 is running. If BI1 (Compressor Status
Input) becomes de-energized while the compressor is running,
a high pressure alarm is triggered. The high pressure switch
and low pressure switch are in series. Check both switches if an
alarm occurs. The alarm will de-energize the compressor output
for two minutes and then re-energize the output.
Summary of Contents for RSMD-CM
Page 1: ...RSMD CM Technical Guide ...