110 V AC Fan Motor Timer

I am working on a project that some friends and I are making (Circle Studios) Right now we are using a stage lighting controller to turn fans on and off to inflate and deflate large jellyfish we built. I am new to Arduino and would like to know if its possible to use an Arduino to control the on and off setting of the fan. How would I go about doing this and finding out about how to wire it up. The code is fairly simple, I am looking for help with the schematics of how to connect an Arduino board to a 110V AC motor.


You need to accomplish two things - You need to boost the voltage/current, and you need to isolate the high-voltage from your Arduino.

You can get isolation with a relay, an optoisolator, or a solid-state relay (which has an optoisolator inside).

An optoisolator does not boost the power, but some optoisolators can drive a TRIAC which can control/switch AC.

A relay will isolate and boost the power, but the Arduino only puts-out 5V at about 40mA, which isn't enough to drive most relays. There are some "sensitive" relays that will work directly. That would probably be your best bet. Or, you'll need a transistor or MOSFET to boost the signal (it just needs a little boost) to activate the relay.

You can get solid state relays that will work directly off the Arduino, but the cost is probably going to be a bit higher.

P.S. An Arduino might be overkill if you just need a timer...