Door Chain Confirmation

Hi! So every night, my wife makes me go to the front door to confirm that the chain is on the door. I was wondering if there was a way to add a wireless sensor to the door to provide remote confirmation. The chain is metal, and the receptacle for the chain is metal. Wouldn't that conduct a current? So if I put a small battery with a current on the chain, and an Arduino with a transmitter on the door, with a wire connected to the receptacle, then I should be able to detect whether there's a current coming from the chain being hooked up, right?

Would this work?


That won't be reliable. The contact between each chain link is not always going to conduct current.

I'd put a small magnet on the chain and a reed switch or hall-effect switch underneath its 'locked' position. You could even put a mechanical microswitch under that position. RadioShack (in the US) has some really tiny switches that could be useful.

This really doesn't need an Arduino, but it's a fun project to practice with.

Maybe an Arduino can monitor the chain in place.
At bedtime it checks to see if the chain is in place (use the magnet idea) beep a piezo every 5 minutes if it isn't.