Power Switch between two AC sources

**JohnChimpo** · 11-01-2004, 03:23 PM

I have a 300 watt rms inverter with two outlets that i bought from radio shack the other day. but being as my battery doesnt hold much of a charge, i want to be able to power it via the wall outlet when i am at home syncing for new songs and stuff. is there any way that i can switch between the inverter power and the wall power without polling the cord out every time? and not as important, but if it is possible to do it without interrupting the power going to the computer, so it doesnt shut off

**pip** · 11-01-2004, 03:59 PM

Couldn't you just hook up a charger to your battery?

**Fox_Mulder** · 11-01-2004, 04:27 PM

I think this might be a job for a DPDT relay. Although you would need a source of power to trigger it. The Active and Neutral will be switched by the relay, but the earths can be wired together. I think, not too sure about this. Can someone verify this is correct/change it?

**VanMan69** · 11-01-2004, 04:38 PM

Battery chargers aren't rated for that kind of draw. They're usually 3-10A.
There are boxes that you can get that are meant for this application, though. Look at RV sites.

I don't believe there is a way to safely switch the AC power between sources. You can also get inverters that have AC input for this kind of application. Again, you want to look around sites that sell RV equipment.

**JohnChimpo** · 11-01-2004, 04:50 PM

I will check rv supply places for something like that. A friend and I, we work at radio shack together, drew up a schematic using a dpdt switch (one with no neutral) and a box with the connection from the inverter coming in and the power from the wall coming in and then hooking them to the switch and then the switch (load) to an outlet. but i would rather not have to build this. it would be a big pain in the a** to me is all. let me know if you think of anything else

**jcdillin** · 11-01-2004, 04:56 PM

I actually built a unit that did just that when I worked at the shack

, it was actually quite simple all I did was take a small transformer and attached to the plug that I would plug into the wall and used that to activate the relay into House Power mode. So when you unplugged it from the house the relay would release and switch the computer back to being able to power it from the inverter.