So I'm looking for an inverter to power small devices to put in the car. Mostly, I want to be able to power my battery charger (LaCrosse BC900). I don't need to power anything large like a TV or even a laptop, though that would be a plus.
Do the Walmart specials work as well as anything else for this type of application? Or do I need to get a little spendy? I'm thinking Walmart but I don't want to be let down when I need it.
A quick search here at ETS didn't bring up much more than people have them.

I'd go with a Vector Inverter (Red ones), there cheap and just about anywhere,400 watts or greater.

http://www.invertersrus.com/vec033.html

Hi Nishnabotna

I just use a 12v 2000mA DC - DC converter to power my Technoline iCharger IC8800 (LaCrosse BC900) from a Car Cigarette output. (just set it to 3V and ensure the tip polarity is correct)


http://www.amazon.com/12V-2A-DC-Converte...7755&sr=1-9

Oops my bad, I was thinking 110V inverter. Sorry, vector also makes a DC to DC inverter as well. Am_Fear_Liath_Mor's one is a good one as well as the http://www.amazon.com/12V-2A-DC-Converte...775&sr=8-38 .

I use a small 175w inverter with a USB port. I can charge any of my personal electronics and AA battery charger through the lighter port.

The thing is you do not want to charge anything higher than a laptop through the lighter port because it isn't designed for high current continuous draw. That's why a number of high drain inverters have hard-wire connectors so that you can charge off the alternator. I can't imagine how those electric food coolers or TVs can run for very long off a lighter port unless it has an auto shut-off circuit to prevent damage to the port.

http://www.dealsmountain.com/deals.php?id=6917

Great - these are nice and inexpensive. I was afraid I would have to get one of them $100 deals to actually get decent output.
I hadn't thought of just a DC/DC converter before - that's a good idea.

I've read somewhere that you can't go above 700 watts with an auto inverter, and that you should go directly from the battery with the 700 watter. I've owned a 700 watter, and returned it because it only had battery hookups instead of a lighter plug. Now I use a 400 (lot cheaper!). Anyone know if the above is true? Can you go higher than 700?

Not from a lighter socket.

Even 400 watts at full capacity is pushing the envelope. On the DC side, you're drawing nearly 30 amps. The wiring for a lighter just isn't designed for a sustained draw of that size.

The 400 watt inverters I've seen came with both lighter socket and battery clip attachments.

The 1000 watt I got has battery clips only. And the instructions strongly recommend a better (permanent) connection for anything other than casual use.

Most cigarette lighter sockets are rated for 15-amps or so. Look at the fuse to confirm this, it’s probably a 15-amp fuse. Ohms / watts law says you will only get 207 watts out of a lighter plug. 13.8 volts times 15 amps comes to 207 watts.

If you want or need more then that, you should run a new line from the battery with stranded wire (don’t use Romex or any other solid wire) to wherever you are going to mount the inverter. Don’t use a cigarette lighter plug, if you buy one from Radio Shack they are rated for only 10-amps according to the package.

Hard wire it to the inverter or buy Anderson plugs or pole connectors.

300 amp arc welding cable would be a good choice.



Inverters pull a lot of power out of a battery without the auto running they will kill the battery fast. A 400 watt inverter draws 28 amps when running at capacity. And that doesn’t take loss or less then 100% efficiency into account.


An auto battery is not made to be drained like a deep cycle battery, do this a few times and you will be buying a new battery.

I don't have a lot of power needs, so I think this one would fit the bill pretty decently
http://www.amazon.com/Xantrex-Technologi...943&sr=1-23
Enough to charge AA batteries with the BC900 or a cell phone, small things like that.
Thanks for the thoughts.

Most cell phone chargers are 5 to 9 volts DC, its very inefficient to convert 12-volts DC to 110-volts AC to use a wall charger to covert it back to 5-volts DC.


Better to get a car charger for your phone that steps down the 12-volts DC to 5-volts DC (or whatever voltage your phone uses to charge with)



Also you can find 12-volt powered AA battery chargers or solar battery chargers. Or convert (if you are electrically inclined) a 110-volt battery charger to run on 12-volts.


This way you are still doing the charging you need but without all the power loss that comes with an inverter.

I would still want an inverter for things you can’t run on 12-volts. But the demand for it can be much lower when you convert things to run on 12-volts.

Thanks for the great info, BobS.

I already purchased a pole connector. I didn't know about the stranded wire thing. Great advice.

I grok that, but I haven't yet found a 12V charger for the phone. Besides, I figure as long as the car is running I'm not too worried about efficiency. It's free power that wouldn't otherwise be used.
Well, I suppose you could argue it would otherwise go to the spark and perhaps eek out a tiny bit more millage but I don't think enough to really worry about.

Solid wire can break if it’s repeatedly bent or if exposed to vibration, this is why in autos you see stranded wire.

700 watts is indeed about the most that should be drawn from a 12 volt vehicle electrical system, This is because the alternator cant supply much more than that, and drawing more than the alternator can supply, will either risk damage, or will discharge the battery even with engine running.

With a large heavy duty battery, several thousand watts can be used briefly, but about 700 should not be exceeded for any time.
(unless the vehicle is fitted with a larger than normal alternator, or double alternators, which is not common)

If the inverter is pluged into the cigar lighter then I would limit the load to about 150 watts, cheap inverters are not that efficient, and an output of 150 watts could be about 15 amps input, which, as others point out, is a common fuse rating.