I blew my #30 fuse when I was tryin to use a 300watt inverter for my laptop. its a 20amp. Did I do something wrong to blow it. It worked for about a minute, then stopped. I just got time to check it today and that's what the problem was. Does that mean my 300 watt inverter is too much, or is there something wrong with the inverter?

 

How many amps is the inverter?

 

300 watts / 12V = 25 amps

 

In the inverter manual it says 35amps. So can I just put a 40amp fuse in there or do i need to get a different inverter?

 

The draw on the 12V would be 25amps if the inverter was 100% efficient, which it's not. The 35 amp draw listed by the inverter takes into account the conversion loss, etc.

Most inexpensive inverters will have the same losses and therefore the same current draw.

Whatever you do DON'T put in a higher amperage fuse, because it could overheat wiring in the car and damage the insulation or cause a fire.

To eliminate the extra conversion losses, see if you can get a laptop supply that takes 12V directly as the input ("laptop car adapter").

If I remember correctly, the cigarette lighter jack at the rear of the center console has a 30A rating, while the one on the dash has a 20A rating. Try the jack at the rear of the console.

Steve

 

Neither of them work now. I only checked one of them in the fuse box because I only had a minute, but I'm pretty sure it blew both of them because when the first one stopped working I tried the second one. And the inverter is 300w continuous 500w peak.

 

Most likely your going to have to run a new fused line from the battery to run the inverter correctly.

 

That's retarded. lol. Why can't something like this just be easy. I found a car adapter for my laptop, but its 50 bucks. The inverter was free. I'm gonna see if I can get a converter that is under 20 amps and see how it runs before I spend 50.

 

Would a 150 or 200w inverter, but under the 20amp limit?

 

Try a 150W inverter. That's just over 12 amps. You really only need to cover the power requirements of your laptop. My old one ran fine on a 75W inverter, but yours may differ.