Nordic ATWC Series, Installation And Service Manual, Page: 100 / 106

PRELIMINARY: 24-Sep-2021 Page 100 002536MAN-00
TABLE A3 - Control Board Connector Descriptions (Bottom)
Name Description
GND BACnet MS/TP Ground for shield if required.
B BACnet MS/TP RS-485.
A BACnet MS/TP RS-485.
STAGE1 Compressor Stage 1 Starts / stops the R410a compressor.
STAGE2 Compressor Stage 2 Starts / stops the R134a compressor.
RV#1 Reversing Valve#1 Unused.
RV#2 Reversing Valve#2 R134a reversing valve: OFF in heating mode, ON in cooling mode.
SOL#1 Solenoid#1 Unused.
SOL#2 Solenoid#2 NC1 solenoid valve coil: OFF in cascade heating mode, ON in other modes
24VAC Power supply for board 24VAC power for control board.
COM Power supply for board GND for control board.
AI_5 Analog In Channel 5 Optional type 3/7 10k hot tank temperature sensor for HTS/CTS Setpoint Control.
AI_4 Analog In Channel 4 Optional type 3/7 10k cold tank temperature sensor for HTS/CTS Setpoint Control.
AI_3 Analog In Channel 3 0 to 5VDC or 4-20mA user settable with board jumper.
AI_2 Analog In Channel 2 0 to 5VDC or 4-20mA user settable with board jumper.
AI_1 Analog In Channel 1 R134a compressor current sensor.
AI_0 Analog In Channel 0 R410a compressor current sensor.
GND Ground pin Ground for analog sensors.
GND Ground pin Ground for analog sensors.
5VDC Power for analog sensors Provides 5VDC regulated power supply for sensors.
12VDC Power for analog sensors Provides 12VDC regulated power supply for indoor & outdoor MODBUS boards.
24VDC Power for analog sensors Provides 24VDC unregulated power supply for sensors.
A MODBUS RS-485 for indoor & outdoor MODBUS boards.
B MODBUS RS-485 for indoor & outdoor MODBUS boards.
GND MODBUS Unused.