Greetings and a happy new year..
i have a question on how to connect a proximity sensor to arduino. So i know that a 24V sensor must have some sort of isolation with arduino and i have a optocoupler for that (could use voltage divier but non the less). All i am not sure of is...do grounds from 24V(sensor side) and 12v (arduino side) have to be connected together in order for this to work? Or are ground supposed to be seperated to corresponding power supplys?