Electric Power Question

[philo111]

I have a Camper Box Truck with a 14' box. I also have a 10,000 BTU portable A/C that uses 1200 watts / 10.8 amps).
I would like to run the A/C for several hours without a Honda type gas generator.

I was thinking:
I could upgrade the Truck Alternator to one that produces
100 amps at idle.

Get a good quality Deep Cell Battery that holds 200 amps.

Get a 3000 watt inverter.

Plug in the Portable A/C.

Start the Truck and just let it idle for hours when the A/C is
on (the engine does not over-heat).

Would this work?

Thank you for your thoughts!

[pianotuna]

Hi,

You would need to know the alternator duty cycle.

A 3000 watt inverter may well not have enough surge capacity to start the roof air.

If I were starting over I'd move to a 48 or 24 volt battery bank with a 4000 watt inverter.

It would be far less expensive to get the 3500 watt Champion inverter generator that comes with built in remote start.

[wa8yxm]

Not likely, First the specified battery bank is 200 amp hours (A pair of GC-2 Deep cycle) per 1,000 watts, so you need more battery

Also you need about a 000000 ga wire from the alternator to the batteries, and from there to the generator. I'd go 200 amps at idle on the Alternator minimum, and expect it to be a short lived alternator.

You are much better using a nice Quiet Inverter generator.

[SoundGuy]

Moderators - is this not a duplicate post disallowed under forum rules? :S

[time2roll]

Even with alternator assist the 3000 watt inverter should have 4 to 6 batteries as a minimum or 400 to 600 amp hours. Typical lead acid is best to use only half rated capacity so you might get an hour on just battery and several hours with alternator cranking 100 amps into the mix.

If you have any roof space I recommend 500+ watts of solar to assist the running and to recharge the battery asap.

[1492]

Moved from Technology Corner

[KD4UPL]

It would work but I see lots of problems. First, if this is a fairly modern diesel engine you don't want to idle it "for hours". This will result in fuel dilution of your oil. You need to speed up the idle to about 1,000 RPM minimum to avoid "wet stacking".
Alternators aren't really designed for long periods at high outputs. Any alternator that will produce that much power at 1,000 RPM will likely be very large, you might even be looking at needing 2 alternators. Either way, overheating of the alternator, particularly with a stationary truck in hot weather could be a problem.
A 200 amp hour battery bank is probably pretty small for this application. If the air conditioner requires the full 3,000 watts of the inverter to start (and it well might) that's nearly 300 amps on the DC side. Even if your alternator is supplying 100 it might be hard to get that much out of a 200 AH battery. Really, a starting battery might even be a better application.
I'd go with a much larger battery bank.
In the end this is likely to be more expensive, use more fuel, and be louder than a Honda generator. Why do you object to the Honda? (or Yamaha for that matter?)
If this is a diesel truck I would do what the big rigs do, get a diesel powered Auxillary Power Unit (APU) and run that to power your AC.