Not so good at electrical circuits, so I need help with 1 issue to complete my first project. I have an external limit switch, that when pressed, will pass 12V. When not pressed, it passes 0V. I would like Arduino to do something when the limits switch is pressed. I've tried a few different soluti…

One way . :slight_smile: [sw-12V.png]

AutoEverything: I have an external limit switch, that when pressed, will pass 12V. When not pressed, it passes 0V. Not good enough! :astonished: From your further description, the limit switch actually disconnects the motor when pressed, so you need to explain why it "passes" 12 V when pressed. …

Thanks for the very helpful info. I'll post back with the circuit info after I switch the ACS758 from parallel to series. The resisters in series do make for an easier path, but since I already have the ACS758 in place, I will try that first.

Using 12V limit switch as input

Other Hardware General Electronics

LarryD July 23, 2018, 1:28am 2

GND on Arduino must be connected to GND of the 12v supply.

Google resistor voltage divider to get 12v down to 5v (if this is a 5v Arduino).

A 6.8K (R1) and 4.7K (R2) divider should work for you.

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Using 12V limit switch as input

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