Other PLC-optocoupler-3wire_sensor


Well-Known Member
Licensed User
Normaamly cınnecftion reading 24Volt(Right side) .its normal.

But .I connected Optocubler board like under below. Iam reaading A-B points 12Volt.
Why reduce voltage. This is problem for PLC.

How can i fix? What/where is problem.

I am not Elektroinc tech. Please explane simple. Thanks.
upload_2019-8-6_15-49-17.png upload_2019-8-6_15-57-50.png

Last edited:


Well-Known Member
Licensed User
Use an external source. The device should not sink more than 3mA at 24 V. Is sensor able to work at 24 V? I don't have any info
sorry my late anser. (national holiday)

I tried External power source. its not changed.

Sensors : DC10...30V