I've done a ton of searching, but I've yet to find any diagram that I can understand showing the ground wires and everything so that I can really understand what I'm doing. So I made my own graphic. I have two power sources (really just one rechargeable battery that can simultaneously output 24v and 12v) and want to be able to switch in between the two. They'll be driving an amp that will sound best at 24v, but won't last as long with regards to battery life, so it would be nice if I could just switch between the two as the situation warrants. Here's my limited understanding in one simple diagram. [IMG]https://i.imgur.com/OELHr8Y.png[/IMG] Anybody care to straighten me out? Thanks!

Hello, I'm upgrading switches in a condo with newer Decora switches and plugs. I was working on the kitchen yesterday and ran into a roadblock. The garbage disposal wall switch has three black wires - 12 gauge wire on a 20 amp circuit. Two of the wires are backstabbed and one is curled around the bottom screw. (I'm not sure if this matters, but this garbage disposal switch is in a double outlet box with a plug that has six,12g wires - 2 red/2 white/2 black. I needed to buy upgraded backwire Decora switches to accommodate the additional wires in all of the kitchen plugs.) The new switch only has two screws and will not accept a 12 gauge wire backstab. I'm aware of "pig tailing", and I was going to connect two of the wires together, but I'm unsure of which two wires I can safely connect together? I don't want to cause a fire. Is there a way for me to confirm which two wires can safely be pigtailed together? Thank you.