Power Inverter

[Josh Richardson]

Im trying to find some technical thoughts on why my power inverter is blowing fuses, its actually blowing fuses now right when I plug it in without any device being plugged into it. I have used this inverter many times with zero problems until I drove to Texas a few days back, I unplugged my laptop and attempted to plug in a portable DVD player to charge it when it blew. Ever since then it just blows a new 15 amp fuse whenever I plug the inverter back in without any device plugged into it. Any thoughts anyone?

 

[James Hilger]

Is it hooked to a cigarette lighter, or to the battery? If it's to the battery then could be the hot wire is touching a ground somewhere.

 

[Josh Richardson]

Sorry, forgot to mention its plugged into the cigarette lighter outlet. I have two of them in my car, it blew both of them....I replaced the front one with the required 15 amp fuse and not the back one. It blows the fuse right away.

 

[James Hilger]

If it worked before then i dont know. I've never been able to use mine plugged in, but that was with a load. I know car amplifiers will pop fuses sometimes when there no good-blown. Never had a invertor blow yet, so i don't know if it would do the same or not. Hopefully it's something simple though.

 

[Jason Foster]

Time for a new inverter likely. But yes, check for a positive - negative short first.

Seriously suggest getting it hardwired with quality fuses at the battery with heavy gauge wire.

 

[Rob Wadsworth]

Whenever it can blow a fuse straight away, I would venture a guess and say there is a dead short somewhere within the unit. Check the wiring in and DON"T put a bigger fuse back in; as this could lead to an electrical fire.

 

[David Wolfson]

Sounds like a short in the inverter indeed. Unless it's a deluxe sine wave type I'd just get two other ones. Since one ought not be loading an accessory socket more than 10A long-term anyway (the fuse may be 15A or 20A but the plugs aren't wired for that), I'd get two of the little $30+- 100W jobs without an annunciator to scream at you that just shut themselves down with overload, over-temp, and over- or under-voltage. Keep them cool and drive in peace.

In my experience the inductors in many laptop computer AC power blocks make a mighty spike when you unplug them from a live socket. That could have done in your inverter. Along that line you might look into getting a DC-DC power block for computer in-vehicle use. They're more efficient about staying within the 10A limit on the accessory socket end AFAIK.

 

[Greg Campbell]

Maybe an input filter capacitor starting to leak? (electricity, but also possibly electrolyte) You might pop the lid and have a look.

 

[Josh Richardson]

I have no idea what Im looking for when I pop it open but thanks for the suggestion, I'll probably just pick another one when I get back to Iowa and then start preparing to hardwire this from the battery. I assume then I can just put one of them big inline fuses on some 8 or 4 guage wire or something.

 

[Mark Blue]

Along that line you might look into getting a DC-DC power block for computer in-vehicle use. They're more efficient about staying within the 10A limit on the accessory socket end AFAIK.

If I were you I'd think long and hard about the suggestion David made on the DC to DC power adapter, especially since you are in the market for purchasing a new unit. I had an pure sine wave inverter, then someone suggested the above and I had no idea what they were talking about. I did some searching around here on the forum and using Google and found an abundance of information on the subject. I ended up buying a Lind brand DC to DC adapter and have been ten times more satisfied than what I had in the inverter, and it was an expensive pure sine wave model from Lind. Check it out and let me know if you need any links to previous posts on this topic.

http://www.lindelectronics.com/cgi-bin/store/shop.cgi/!ORDERID!/Special_DC_Adapters/x/dbx_gen_Special_DC_Adapters_mfgs/

 

[Josh Richardson]

Thanks, I'll take a look at that sometime this week.

 

[Brett Roberts]

Just had to comment on this, as I'm experiencing exactly the same issue right now. Was out testing equipment last night and my cig lighter outlet suddenly stopped working. Today I determined the fuse was blown, so I replaced it with a spare. Plugged in my Garmin; no problem. Plugged in the inverter (with nothing attached); immediately blew the spare fuse. Went through this a few times before deciding to hook up an older inverter I had laying around, just to make sure the cable running from the inverter to the outlet wasn't at fault. Sure enough, the old inverter worked fine, and was able to run for about an hour without blowing another fuse in the car.

FWIW, it's the Wagan 400 W model that has evidently crapped out on me after only a couple months of use. The most I ever used it for, simultaneously, was (1) laptop, (1) Rockies amp, and (1) Garmin GPS connected via the USB power port on the inverter. Rather annoying, as I had it nicely attached to the side of my dash with velcro, which won't be possible with the old inverter due to its shape and weight.

 

[Sean Waugh]

Running inverters of any size off a cigarette lighter plug is a dangerous game (at least when considering the demands that chasers typically need). Many inverters come with a set of cables that allow you to plug it in cigarette lighter, but that doesn't mean it's a good idea. They sometimes go bad, as many have found out, and start blowing fuses. The real problem is when the fuse DOESN'T blow. I've had a situation in my personal car where the socket actually shorted before the fuse and welded itself together, ruining the entire socket. I ended up having to replace the whole thing which is a pain in the ass. Bottom line, if you need an inverter find a way to tie it to the car battery.

What I do is run a line of large cables (8-10 AWG) to the battery and put in my own fuse box inside the cabin somewhere. I also put a switch in line so I can turn the power on and off. If you run large enough cables, you can run a much larger inverter inside, say an 800 W inverter. This would give you enough power to run almost anything you'd need (say and xbox and a 46" LCD monitor to play it on), without having to worry about blowing any of the components hardwired into the car. If you do something like this, be sure to put a fuse as close to the battery as possible to prevent the wire being nicked somewhere along the way and directly shorting out your battery.