I am using an 500w electric hoist/motor that runs off 230v ~ 50Hz mains supply. This has a 3-way switch UP/off/DOWN I would like to connect this switch to the arduino digital inputs effectively just to send the UP/off/Down information to a computer.
What resistor should I use with this kind of power so I don't kill myself and the arduino board?
One thought might be an on-off-on double pole switch, and wire one pole for A/C, and the other pole for the Arduino. I would want to test it with a multimeter first to make sure there is no current leakage between the two poles.
Alternatively, I could imagine putting two different colored A/C leds on the up/down circuits and use a color sensor on the Arduino.