size of wire needed to hook 200 watt invertor to car batttery?

Question

I am hooking a 200 watt invertor in my car. It has to be hooked to the battery because of the size of my laptop. No one seems to know what size wire to use

Answer 1

At 200 watts. and assuming something less than 100% conversion efficiency, I would assume about 20 Amperes draw from the battery. That said, I would use at least 8AWG wire if you're going to have any length to it.

Don't go by building codes as they recommend 12 AWG. You need to consider that 120V will result in less losses simply because of the higher voltage. 8 gauge wire should work reasonably well for you while minimizing losses.

Answer 2

It depends on how long the wire is. Assuming the wire will be less than 10 feet long, an 8 gauge COPPER wire will do the trick. Don't use aluminum or composite wire, and be sure that the insulation is either plastic or rubber..not wax.

Amperage is the real issue, not wattage.

Answer 3

I am an electrician. The answer is # 12 AWG. 200 watt divided into 12 volts from your car batt. is approx. 16 amps.....#12 size wire is good for up to 20 amps..Make sure you have an inline fuse rated for 20 amps just after your battery connection.
Ken

Answer 4

First off, find out how many watts draw the laptop is, then go from there.

With that I agree with Ken.

Answer 5

ten guage should be fine but will a 200 work,my 450 overheats with the laptop

Answer 6

if your installation manual doesn't tell you...I'd run at least 14 gage. this is a heavy wire and will normally run your system. 10 gage is ok...but hard to handle and unnecessary for this application.

Answer 7

10 gauge should b fine