car power inverters

I don't know a whole lot about using inverters with production gear but I have a feeling you would want a true sine inverter for consistent power and for the longevity of your lights. Also make sure the car battery can sustain that much wattage draw.
 
I'm sure you will get better info than mine, but you did say the car is running. I think based on my inverter use (though not on lights) that you will want to have the strongest heaviest duty alternator you can have.
 
In the absence of someone better informed, I'd say your alternator puts out 50 amps at 13 volts - that's 650 Watts. You're going to lose some of that inverting to 120/240v, and in real life specs are rubbery and things don't last as long as in theory and I'm not good at maths or auto electrics so my guess would be you've probably got up to 20 minutes of lights before you drain your battery and maybe wreck your car's electrical system. Some hobbyist electrician can probably make a better guess, but I think you'd be better off hiring some LED lights.
 
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Yes, people have run refrigerators and other things off big inverters connected to a car. You can probably get this to work. I haven't done this, but I would have to really not have any alternative before I attempted it. If the generator is small enough, I'd put it in a plastic storage container and seal it up with tape or something to keep the fumes contained for the trip.

But if you do go with the inverter, some things to think about:

Does your vehicle have a big enough alternator? You're vehicle may have a 150 or 200 amp alternator, which will be plenty.

To get that power, just like a generator, it has to be running at higher RPMs. Do you want your car idling at high rpms for minutes/ hours at a time? Someone would have to be in the car pressing on the throttle.

You should monitor battery voltage to know if the alternator is doing its job or if your battery is draining.

You need a way to get a good solid connection from the battery/alternator to the cable to the inverter. Cable clamps like on a charger won't provide a good enough connection.
 
I have used a battery-inverter (jumpstart battery) rated at 25Ah which powered a (measured) 60W draw LED for 3.5-4hrs continuously. You could get an RV/boat/solar deep cycle battery to pair it with. That would give you hours depending on how many amphere-hours (Ah) it has, with the side benefit of not potentially leaving you stranded. I've looked at models up to 250Ah. Pricey though, around half the price of a chinese knockoff of the little honda 2K generator. Might be able to rent one from an outdoors supplier, caravan or boat shop.
 
Hey Patrick,

In another life I used to design and sell inverter systems on large yachts, so maybe I can help.

First, regarding incandescent lightbulbs, you don't care if the inverter is full sine wave, or modified. Though, I don't know if the modified would change color, probably not enough to worry over.

Your power requirements for both the car (charge source), inverter, and batteries are at the most basic level, solved by Ohms Law. Watts = Amps/Hr x Volts. For most inverters, add about 10% for conversion losses. Your 1050W load should work ok with a 1500 watt inverter, however many inverters have a duty cycle rating. You didn't state the duration of your need, so if it is extended, make sure the inverter is capable, many aren't.

Another note, and this is true no matter what you are doing with AC power in the field, make sure you have grounding on the AC circuit. There have been many cases where accidents in field production have led to DEATH! Stay out of puddles and keep your socks dry.

The typical car battery reserve will be between 50 and 100 amps/hour depending on size. You can't use all of this, and if you did, your car won't start afterward. Go back to ohms law and you can figure the amps needed over time.

The typical automotive alternator will produce 50-75 amps/hr, though larger pickup trucks are often 130amps/hr. As was previously mentioned, to get that output, the engine will need to be revved up somewhat, maybe to 2500rpms. So for an 85amp load, you will be marginal on keeping your battery charged without a larger vehicle. And as previously mentioned, for this type of load, alligator clamps or a cigarette lighter outlet won't hack it.

The real conclusion here is that creating 120VAC from 12VDC is a really inefficient prospect unless the durations are pretty short or the loads are small.

FWIW, I have a Honda inverter type generator and with the tank vent closed, it is pretty tight from a gas fume point of view. Most of the smell associated with it would come from the exhaust shortly after shutdown. Let it air out after use and you might avoid the stinks.

LED lights are really efficient and usually run directly from 12V sources. I get pretty good run times using a 600w equivalent LED and a basic Bescor brick. An automotive battery would give you some extended run time.

Hope that helps a bit. Grant

Edit: You might consider flos to somewhat reduce your AC load, but you would want a full sine wave inverter for those.
 
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