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Operation & Maintenance Manual
COM
OUT2
OUT1
POW
DIN
AIN1
AIN2
COM
OUT2
OUT1
POW
DIN
AIN1
AIN2
Fig. 11
Fig. 11 describes input/output port composition of PLC. All input/output signal for chiller control is
connected to PLC, it is delivered to PLC as input or it is approved output from PLC. Used
input/output for this product among input/output of PLC is shown below.
• POW: it is used to provide power to PLC
• DIN: it is used to provide switch input signal to PLC
• OUT1~OUT2: it is used to deliver output signal from PLC.
• AIN1~AIN2: it is used to deliver sensor information to PLC.
• COM: it is used to connect communication between PLC and HMI and MODBUS communication.