Orion System VCC-X Controller - Manual (Page 53)

VCC-X Controller Technical Guide
INPUTS & OUTPUTS
53
RSMV Inputs & Outputs
Refrigeration System Module for VFD
Compressors - Inputs & Outputs
+5V VDC Power
This output is a 5 VDC output that supplies power to the Suction
Pressure Transducer.
SP - Suction Pressure Transducer
The Suction Pressure Sensor is 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.
This temperature combined with the measured temperature of
the coil temperature sensors is used to calculate Superheat. The
Superheat is used to drive the Expansion Valves to maintain a
certain Superheat Setpoint. The saturated refrigerant temperature
is also used in the Dehumidifi cation mode of operation to properly
control the compressors to maintain a given Suction Coil (Saturated)
Temperature Setpoint.
+5V VDC Power
This output is a 5 VDC output that supplies power to the Head
Pressure Transducer.
HP - Head Pressure Transducer
The Head Pressure Transducer is 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 - Coil (Suction Line) Temperature
Sensor 1 & Sensor 2 Input
These Sensors are used to measure the Coil (Suction Line)
Temperature after each evaporator coil line. This temperature
combined with the calculated saturated refrigerant temperature is
used to calculate the Superheat of each individual evaporator coil.
The Superheat is used to drive the Expansion Valves to maintain a
given Superheat Setpoint.
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 a relay output from the compressor VFD drive. 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 a relay output from the auxiliary contact on the compressor starter.
If Binary Input 2 opens, Compressor 2 Enable Relay will de-energize
and a Compressor Alarm will be generated.
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 - Modulating Compressor Signal
This 0-10 VDC output is used to control a Modulating Compressor
to maintain the Cooling Supply Air Temperature Setpoint.
AOUT2 - Condenser Fan VFD Signal
This is a direct acting output signal that is used to modulate the
Condenser Fan VFD (0-10 VDC signal) on an Air Cooled unit.
EXV-1
The Electronic Expansion Valve 1 is driven to maintain Superheat
for Evaporator Coil 1 of its particular refrigerant system.
EXV-2
The Electronic Expansion Valve 2 is driven to maintain Superheat
for Evaporator Coil 2 of its particular refrigerant system.
RLY1 - Compressor 1 Enable
This relay turns on the Modulating Compressor.
RLY2 - Compressor 2 Enable
This relay turns on the Fixed Compressor.
RLY3 - Condenser Enable
This relay turns on the Condenser Fan / Water Valve.