Motor loads vs Resistive

Hi all! We are coming to the community for our Van conversion, but not in the normal dweller sense. We are a piaggio ape Van conversion food truck that runs our frozen yogurt machines off of a lithium battery pack. We have a 3000W inverter charger connected to 4 lithium 270amp hr wired in parallel. One machine is 1750W, one is 600W. The surge capacity is 6000W for 2-3 secs. We are trying to determine if this is sufficient for the continuous draw as well as the motor load required. The math all works on paper but the system is not functioning correctly. We have a warranty claim to the manufacturer as even with the larger machine only it is not working. We are also seeking advice to see if anyone is up for the challenge to work these numbers while taking into account this is a motor load, which most inverters reflect a resistive load (like incandescent lights). Combined the machines are 1/2 & 1/3 HP.

You might want to check your wiring size to see if it can handle that many amps. 6000 watts (500 amps!) takes some HUGE wire.

Also, can the batteries supply an instantaneous/surge of 500 amps!? Dunno - check the specs.

Lowering the number of amps may be the only way to do it, and it can be done by increasing the voltage and using an inverter made for that voltage. Maybe go to 48 volts (your four batteries in series instead of parallel) and a 48 volt to 120 volt AC inverter. That way your 6000 watts only draws 125 amps, which may be doable. Be sure to use wire, fuses, etc. for 125 amps.

Check the battery specs to see if they can pass that amount of current.

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Greetings & Welcome!

I love those Ape vans…

Have you tried the system on shore power to make sure it works as expected?

Besides the wiring, as Axel mentioned, inverters can be finicky. They are often not up to the capacity they are rated at. I have read that larger loads should never exceed 2/3 of the capacity, and it looks like you’re over that.

Most of the food trucks, ice cream trucks, and road service trucks that I see around are either using a gas generator on the back bumper, or a Redi-Line generator inside. I’m not too familiar with Redi-Line generators, but they appear to be a battery powered, motor driven, electric generator, that puts out the equivalent of shore power.

generators

Cheers!


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