Something else??), triggers a 12V relay somewhere for x minutes, and draws little power when "idle". I'd have to program the hardware outputs, network reception, and timing stuff. - Controller app.

An electrical relay is a type of remote-control switch able to handle high-current accessories. Marlan Davis explains a 12-volt relay and how it works.

Once you activate the relay with 12V power and ground, the relay will power the accessory. A relay is essentially a heavy-duty switch, connecting the high-amp accessory to a clean 12V source.

The relay RY1 will be turned on when 12V dc supply is applied to the circuit. The transistor T1, and hence the relay RY1, is off when the control signal input J1 is 12V. Obviously, we need a ...

2. Switch between 2 different Loads with DPDT switch In this second application we can use the DPDT switch to choose between 2 different load and have a visual indication of what load is connected. In ...