[Chris] and [Dom] wanted to build their own battery backup system on the cheap. They were very creative in sourcing the parts, and ended up putting together a battery-backed CCTV system for about eighty bucks.
Since short power outages are fairly common in the area this battery backup makes sense. We’ve seen some pretty gnarly whole-house systems but this is more of a novelty. That’s a good thing, because the hacking duo decided to reuse batteries which were headed for the scrap yard. They’re connected to a trickle charger which makes sure that they’re continually topped off when mains power is energized. But when there’s a blackout a relay switches an outlet box over to the inverter (also a used part).
The system is outlined in the entertaining video after the break. You’ll see they guys show off the completed build, followed by a walk through of the circuit they designed and how it functions.