Hi, to make the INDIO's digital channels work, you need to power the Industruino with an external PSU 12/24Vdc on V+/V-.
For coding functions see https://github.com/Industruino/documentation/blob/master/indio.md#digital-io
You can connect a standard industrial relay coil to CH6 and the GND terminal right next to CH8. Before connecting the relay, you could first check with a multimeter whether you get 12/24V on CH6 as intended.
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