Find if motor is On or Off

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I want to see if the motor is ON or Off . Don't know if a voltage divider will work in this case. The motor has a physical switch. Its been a long time since high school electronics. I may have drawn the diodes in the wrong directions but hope the image is clear enough to get an idea about what i want to do. This is high voltage 100+ VDC so i want to be careful. Any help would be great. Thanks

Don't know if a voltage divider will work in this case.

No, and it would be EXTREMELY dangerous to even try. With that circuit, you would be directly connecting the AC power line to a microprocessor.

You could safely use a noninvasive AC current sensor to monitor motor current, or an AC optocoupler to monitor motor voltage.

Thank you for pointing me in the right direction. I will use something like the following.

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Good choice!

Your first drawing shows the motor is being few with a full wave bridge. Is your motor rated for this? I have one and they seem to be as rare as hens teeth.

Paul