Fuse size for cig adapter inverter cord?

[Crowz]

I have a 410watt inverter I keep in the car and while my wife was at the hospital today and I was sitting in the car I figured I would use it to power my notebook computer and surf and play games.

All was well for about 2 minutes with the display on the inverter showing 70 watts as the notebook booted up and got into windows then it ramped up to the 240 watts the thing pulls at max power. No prob I would think and then the inverter cut off.

After checking it out I found the fuse in the cig adapter plug had blown. Which actually didn't surprise me when I noticed this 410watt inverter that can surge to 820 watts had an 8 amp 250V fuse in it.

I want to put a larger fuse in it but I'm not really sure what it should have. I figured someone on here would have a cig adapter setup and might have suggestions on the proper fuse size. There is no way 8 amps is right. I'm not sure what the fuse is for the cig lighter socket for the car size wise. Still looking.

 

[Crowz]

Ok found this just now.

In many BMWs, the cigarette lighter fuse is a 20A or 30A fuse.

So maybe a 20A fuse for the inverter?

 

[justinm001]

Get a smaller inverter. You can't increase the fuse without replacing wiring

 

[Crowz]

Get a smaller inverter. You can't increase the fuse without replacing wiring

The wire size on this could do 40 amps no longer than it is. For some reason it was shipped with an 8amp fuse which is way to small. The label shows it can do up to 40 amps surging.

I ordered an assortment of glass round fuses earlier tonight which should be here by saturday. I'll see if a 20 behaves in it. The cars fuse is 20 amps on the cig lighter.

 

[HRTKD]

That 40 amp surge is going to be for a very short period of time. Maybe less than .5 seconds. The wire is rated for the nominal output, not the surge.

 

[Vigo]

The wiring you need to worry about is the car side of things, not the inverter you’re plugging in. I would strongly recommend creating a properly sized ‘hard wired’ power/ground jack that can feed that inverter. I would personally use an anti-spark xt90 connector because its very compact and will minimize arcing damage to the connectors when you plug it in. Just the inrush from a 400w inverter is pretty close to popping a ‘cigaretter lighter’ fuse.