Advantech ARK-2121F User Manual page 25

2.3.1.9 DIO Connector
ARK-2121F offer 8 PIN Isolated DIO and 2 PIN Ground.
Type: 0~3 PIN; DI; 4~7 PIN DO: 8~9 PIN Ground.
Input Voltage: 0 to 30 VDC at 25 Hz
*Isolation level: 3kV
Digital Output levels for Wet contacts:

Logic Level 1: Close to GND

Logic Level 0: Open
Digital Input Levels: for Wet contacts:

Logic level 0: +3 V max.

Logic level 1: +5 V to +30V
Output Current: Max. 50 mA per channel.
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