Digitally controlled AC Outlet


This is an AC 4-outlet junction box that has SSRs (Solid State Relays) built in to allow digital logic to switch on and off each of the outlets.

The SSrs used here are Sharp S108T02 (got these from Sparkfun). Apparently these can handle upto 8A.


The digital logic lights up an IR LED inside the component, which is what optically isolates the digital and triac driven AC side. A 220 ohm resistor was selected (so that the LED gets about 15 to 20 mA, when signalled by 3.3v to 5v).

All soldered , and just before assembly:

Now lets light up something more than just LEDs!:

Here is a single outlet version that was built by splicing in the SSR into an extension cord. A pill bottle was used as an inline enclosure for the electronics.
Note: this one doesn't have a limiting resistor, so a 220 ohm (or so) resistor needs to be added in series, before supplying digital Vcc to the control inputs.