11
RSMD Technical Guide
INPUTS AND OUTPUTS
RSMD Inputs and Outputs
RSMD - Inputs & Outputs
+5V VDC Power
This output is a 5 VDC output that supplies power to the Suction
Pressure Transducers.
SP-1 & SP-2 - Suction Pressure Transducers
The Suction Pressure Sensors 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 Transducer.
HP-1 & 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 & TEMP2 - Compressor Discharge
Temperature Sensor 1 & 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.
BIN1 - Compressor Status 1
When this wet contact input closes, a 24 volt signal to Binary
Input #1 indicates that Compressor 1 is running. Typically,
the source for this is relay output 1. If Binary Input 1 opens,
Compressor 1 Enable Relay will de-energize and a Compressor
Alarm will be generated.
BIN2 - Compressor Status 2
When this wet contact input closes, a 24 volt signal to Binary
Input #2 indicates that Compressor 2 is running. Typically,
the source for this is relay output 2. If Binary Input 2 opens,
Compressor 2 Enable Relay will de-energize and a Compressor
Alarm will be generated.
BIN3 - Outside Coil Temperature / Proof of
Water Flow Status
This input can be used for the following two options:
Air to Air Heat Pump
This wet contact input monitors a Defrost Coil Temperature
Switch on air to air heat pump units. If the compressors are
operating in the Heating Mode and this switch closes, it will
initiate a Defrost Mode.
Water Source Heat Pump
This wet contact input is for the Water Proof of Flow Switch.
If the Water Proof of Flow Switch contact opens while the
Condenser Valve is operating, the controller will react to protect
the system depending on the current mode of operation.
BIN4 - Emergency Shutdown
This wet contact input is used to initiate shutdown of the HVAC
unit when a N.C. Smoke Detector (by others), Firestat (by others),
or other shutdown condition (by others) contact is opened. The
controller remains active and can initiate alarm relays.
NOTE:
The Binary Inputs require wet contacts (24 VAC
only) to recognize an active input. If you provide
dry contacts, the contact closure will not be
recognized.
AOUT1 - Condenser Fan 1 Signal
This 0-10 VDC output is used to control/modulate the Condenser
1 Fan /Valve to maintain the Head Pressure Setpoint.
AOUT2 - Condenser Fan 2 Signal or Waterside
Economizer Bypass Actuator Valve
This 0-10 VDC output is used to control/modulate the Condenser
2 Fan /Valve to maintain the Head Pressure Setpoint or this output
signal is a Direct Acting 2-10 VDC output signal that is used to
modulate the Water Side Economizer Bypass Actuator.
RLY1 - Compressor 1 Enable
This relay enables the Compressor 1.
RLY2 - Compressor 2 Enable
This relay enables the Compressor 2.
RLY3 - Condenser 1 Enable
This relay enables the Condenser 1 Fan / Water Valve.
RLY4 - Condenser 2 Enable
This relay enables the Condenser 2 Fan / Water Valve.
RLY5 - Reversing Valve Enable
This relay enables the Reversing Valve.
Summary of Contents for RSMD
Page 1: ...RSMD Technical Guide ...
Page 41: ...41 RSMD Technical Guide NOTES ...
