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Power Inverters

I am buying an ice cream truck and I need to figure out how to get power to the appliances. Can I just hook the inverter to my car battery and leave the engine running when I need it? I am looking at something like a 5000 watt inverter. Thanks.

Well if you are drawing the majority of the max wattage off of that inverter, your alternator won’t keep up with the usage. My numbers might be off, but at 4000 watts you’re going to draw somewhere in the 300amp range off your battery. You’re gonna need a really high output alternator for that kind use. Maybe dry ice would be better.

Plug into the garage to chill the freezers on the off times and use dry ice to maintain the cool when mobile. If you don’t need that much power, you might be fine for a while but the alternator will be at risk of burning out. You also might want an extra battery.

Thanks, what about these inverter/charger blocks you can buy?

You’re forgetting that inverters aren’t 100% efficient. I think that you are looking at more like 400 or 450 amps for 4,000 watts.

tardis is right, much more amperage. You can use those inverter/chargers then you don’t tap the electrics of the vehicle at all. You just need a stack of several batteries as a power source depending on how much power you need.

I used to occasionally work on mobile coffee carts and they worked one of three ways: they either plugged in to an on-site power source, had a separate gas-powered generator or they had equipment that ran on propane/LPG.

Depending on what kind of appliances you’ve got, an inverter probably isn’t going to cut it (it won’t for most commercial-grade appliances). Even if you can get an inverter that can keep up (keep in mind that the figure on the package is the peak output and they can usually only provide a fraction of that continuously), even a heavy-duty alternator will probably have trouble keeping up at idle. One other solution that’s out there is for some truck applications, you can get an a generator that bolts to the engine that’s separate from the alternator that will provide electricity and modulate the engine speed as needed. But these are usually more expensive (and less efficient) than a standalone generator.

I think you will be better off with a generator. It should use less fuel than leaving the engine running.

When I drove a truck for a living, my trainer had his inverter directly wired to his battery, but you don’t want to do this kind of thing yourself. You could easily start a fire if you don’t handle the installation properly.

I agree with the generator. You should be able to get a 5,000 W generator for around $500 if you shop around. Though you may want to invest in a commercial model instead of a consumer grade, as it will probably last longer with daily use. You’ll want to make sure it can also handle the ‘inrush’ current from starting all of your refrigeration equipment–you might have to switch them on one at at time. (you’d have to do the same thing with an inverter) Or perhaps a generator meant for an RV would be the easiest to install and maintain.

Yeah, what they all said. Plus, cheapie inverters will have lousier output waveforms (and worse efficiency) than high grade. The same is true for stand-alone generators. Some devices will not be happy with the bad waveform; but electric motors would probably be OK.

But I’m curious. You are buying an ice cream truck. How did the previous owner power the appliances, and why does that not work for you?