Folks,


Out of my league here on this one.


I have a lot of dogs. I would like to put a small RV A/C unit on my F350 Long Bed Topper.


The specs on the A/C unit seem to indicate 1200-1600 watts and approx 12 Amps.


I believe I need an inverter rated in the 3k-4k range.


Can our F350, 6.7L Diesel power systems handle this?

 

Probably... I would get a sine wave unit...not cheap..

 

It would be easier and cheaper if you just buy a Honda 2000 Watt Gen and make a hitch mount for it.

The 12 V system on your truck will not handle it. That's 12 amps at 120v or 120 amps at 12V. 1440 Watts.

At idle your alt would need to put out 120 amps and that does not even cover your truck dc needs either.

That also does not take ac motor starting amps either.

Go with the 2K gen, should be ok as other rv's are running those small btu units. Simple and easy this way, quiet too.

 

Thanks for the input. The envisioned use of the A/C was to cool the back of the truck while traveling for my pack of dogs. A hitch mounted generator unit isn't really what I had envisioned. LOL

 

Does the truck have dual alternators?

If so, its feasible. Basic math (not accounting for inverter efficiency / loss etc.)
1500 Watts / 120 Volts = 12.5Amps (ac powered)
1500 Watts / 12 Volts = 125Amps (DC conversion) up it to 130Amps DC to compensate for loss) (these are run state)
Then you have to consider the compressor start surge, lets say for discussion its double = 260Amps (3120 Watts, which your guess for a 3 to 4K inverter is about right. I know a lot of 2500/3000 watt inverters can handle 4 to 5K surges which means a 3KW inverter should easily meet the need.)

The dual alternator rated output current is about 320Amps. (DC)

If you powered the inverter with a couple batteries (such as 2 6V in series) they may absorb the start surge, then the truck is capable of keeping up with the run state and keep the inverter batteries charged.

The wild card is the compressor start surge.

Dual alternators are used in ambulance applications which have huge demand on the electrical system, hence the option.

If you have a single alternator, then I agree with the previous poster; a small generator may be the better way to go.

 

Look for a smaller RV A/C unit, the little ~5,000 BTU/Hr one should be plenty for the 50 square feet or so you need to condition. A 2-3K rated inverter should do the job presuming it has the higher surge rating for compressor starts.


I ran a 2K inverter in my old truck with the single 200A alternator and had no issues with it powering various tools including table saws. Be sure to wire up the BCP mode to enable the truck PCM to monitor the load on the alternator and increase idle speed to compensate. BCP also works well when running a winch as it will rev up the engine when the winch is pulling a couple hundred Amps.

 

Actually, I think the dual alternator setup on the 6.7L is 357A total. (One 200A alternator, and one "standard" 157A alternator)

High Idle option or the auto idle up for higher electrical draw. Also keep in mind I'd bet those Ford alternators do not produce that kind of power when they are hot (which they would be, idling for extended periods on a hot day).

I'd be much happier with the Leece-Neville 200A alternators in the F-750 Ford trucks. These would probably retrofit right in, since they are mounted on the 6.7L in those trucks as well.

There's always the PTO option as well, if your truck is so equipped, so run a generator directly...but these are typically mounted in the bed.

 

Interesting... I haven't picked up the truck yet. The Window Sticker says "extra heavy duty alternator" so I assume that means it has two?

 

Yes, I was looking for a smaller A/C unit but couldn't find one. The 9200 was the lowest I have found so far.

 

Nope. It will have one 200A alternator. You can add the second one later if you choose, but it is some work and money.

 

Sigh... it all comes down to money doesn't it?

 

I have a 5000W inverter in my truck, I've used it to run my refrigerator in the house when the power goes out without any issues.
Think I got it for $150 off Ebay. Cant upload photos for some reason.


My mistake, it's rated at 2500W continuous and 5000W peak, XPower 3000 http://www.xantrex.com/documents/Pow...-3000-5000.pdf

 

Something like this would be another option.

http://realacpower.com/

 

That's a pretty sweet setup. It looks well built and high quality, so I imagine the expense is considerable. I don't love the angle that the PTO driveshaft runs at, though. Nevertheless, that is a great way to make a lot of electricity without taking up bed space. Quite noisy, though.

 

There is one more thing you could do.

As my vehicle is an excursion and has rear air, could you not find a wrecked one and take the rear ac out of it along with the controls?