Thread: Power switch for inverter?

You could wire up a relay between the battery and the inverter, and switch the power to the inverter, or you could simply extend the switch on the inverter. I used to use a relay, but on opening up my relay up one day I discovered that none of the swithes were soldered, everything was socketed, so i just found suitable replacement plugs, and made my own extension wire.

This is simmiler to what i did.. I ran the switch in my dash in series with the one on the inverter that way both have to be on for the inver to function, and i put disconnects on the cable for the dash switch so that i can take the inverter out of the car, plug the disconects together and the inverter will function normally from the built in switch.

I just used cat5 and a keystone jack so i could rig up another switch if i had to take it out of the car.

Why do I need the relay, can't I just hook up a switch on the positive connection from the battery?

Well this wouldent really be a safe situation with normal switches, because of the power load involved and the size of the wire. You are going to have quite a bit of power running to the inverter (300w inverter has a 35A fuse, and that fuse can hold 70A for 1 min.) to find a switch that will handel that kind of amperage will cost you quite a bit (read $50+ and it will be huge).
and you will have to run large (comparitivly) wire to it, when you can just place a relay inline with the power running to the inverter and use speaker wire to switch the relay, or evean better tap the switch inside the inverter and use speaker wire. Using that method you will only use 1 switch costing around $1 and about 50c worth of speaker wire and some electrical tape and solder.

ooh and dont forget to fuse the power lead to the inverter within 16" of the battery! CAR FIRES BAD!!!!!!!!!!!!!!!!!!!!!!

Could someone maybe do up a small wire diagram for what I will need. The power is going from my lighting in my car then I want to to run to a switch(master switch for everything) then from the switch it will split, one goes to the inverter, one goes to another switch to control the LCD. Where should I put relays, the switches and fuses? Thanks

You are running everything off the lighting in your car...meaning the Dome light?? Umm you gonna start a fire. Seriously! The wiring for your lights...any lights is not good enough for a computer...Through an LCD and all sorts of goodies and your gonna blow up...well, a fuse probably first, but still... I highly recomend wiring it to your battery...there is a little hole somewhere in your firewall under the hood...just run wire through it.

Originally posted by jstiltner
Well this wouldent really be a safe situation with normal switches, because of the power load involved and the size of the wire. You are going to have quite a bit of power running to the inverter (300w inverter has a 35A fuse, and that fuse can hold 70A for 1 min.) to find a switch that will handel that kind of amperage will cost you quite a bit (read $50+ and it will be huge).
and you will have to run large (comparitivly) wire to it, when you can just place a relay inline with the power running to the inverter and use speaker wire to switch the relay, or evean better tap the switch inside the inverter and use speaker wire. Using that method you will only use 1 switch costing around $1 and about 50c worth of speaker wire and some electrical tape and solder.

ooh and dont forget to fuse the power lead to the inverter within 16" of the battery! CAR FIRES BAD!!!!!!!!!!!!!!!!!!!!!!

well said. and to further elaborate, the large wire required to have a dirrect switch should be 8-10ga, compared to the wire i used to control the relay, which was 30ga (cat5), and 8ga wire is a good bit more expensive than 30ga as well as the fact that a switch rated for 30a@12vdc is going to be expensive. You can get a 30a@12vdc from radioshack for like $12, and a few dollars more for the wire and switches for it.

I have not wired up anything yet thats why I want to learn all this info before I do burn my car up. MP3DUB, I looked at your wiring diagram on your site...do you have a switch attached to the relay that controls the main power? Can you guys give me a little more info on what to buy, what should the relay and fuse be rated for?