4 car batteries in series and need 3mps current to melt metal.?

Question

I have 4 car batteries in series used for melting metal. Need to have 3amps of current. I tried a 12vdc dimmer switch, but it melted. Any ideas?

Answer 1

To make that work, as suggested, you need to conenct them in parallel, that is, all +'s connected and all -'s connected. This will keep the voltage 12 volts, and the amperage is summed to the total (personally, I think one will do the trick, but it depends on how long you need it to melt the metal, hence why you want 4 batteries for capacity).

Instead of a switch, you need a high current rheostat (like you would find in older welders). This will allow you to limit the current to the work so you don't kill the batteries on your first run. It isn't something your average electronics store has, so you might have to scavenge for it. To switch it on/off, you are going to need a magnetic relay, again something capable of handling a high current. I would also look to junk arc welders for that, *or* you MIGHT be able to find a set of magnetic switch contacts on an old AC unit that will work. These work by applying a low current signal voltage to one side of the contacts. This causes them to close, and the high current amperage flows through the high current side in a switch.

Answer 2

Duh, if you had four car batteries in series, then you put 48 volts into the dimmer. Just use one battery for twelve volts.
The Amp rating will tell you the amount of energy stored in the battery.
If you want a lot of amperage, connect the four batteries in parallel, not series!

Answer 3

Uhm, arent car batteries like 300 amps?

Perhaps you should use smaller batteries like for motorcycles, riding lawn mowers...

Or better yet use a arc welder power supply!

Answer 4

first project is to swap the damaging battery cable, not purely the clamp. be sure you sparkling the grounding element that the different end of the damaging cable bolts to. examine and sparkling each and all of the floor wires and beneficial cables/wires to the motor, starter, and alternator. Have the charging equipment checked and do a load attempt on the starter.

Answer 5

Use one battery and follow Eric's advice.