Diesel Generator

Please excuse me if this subject has been discussed before, but I could not find any threads in my searches.

I am looking to buy a 3010 and use the garage as a mobile dental office, and will never use it to haul toys. I will be towing it with a diesel rig, and wanted to know if anyone has put in a diesel genset in place of the gas unit. For me, it makes sense, and would give me a second fuel tank for my truck as well as the genset.

In addition, is it feasible to consider using the tow vehicle (with 2 alternators) in place of a generator for stationary power?

Thanks for your help!

The only problem you might have is the size of the generator compartment. Fitting an Onan diesel would be tight. But, I think you could figure out a way to get it in there. The biggest downside is cost. Diesels are about twice the cost of a gas. Other than convenience, I am not sure you are gaining a lot with a diesel generator.

Having said that, I would love to have one. I am pretty happy with my 6500 watt Onan though.

I don't think your trucks two alternators are going to produce many AC amps. Might be able to run a few appliances but big power suckers like a microwave or a/c unit wouldn't cut it.

John

John"" I think you said it all. I agree.

Weight and Vibration would be the two drawbacks. The fuel economy would be much better and it would be convenient as well.

Roger, I too would love to have a diesel generator particularly for realibility and longevity of the generator. I also understand you wanting to use it for a second fuel tank for your truck. However, this may be a better option, check it out: http://www.transferflow.com/. I installed the 75 gal TRAXII aux fuel tank in my F-350 so now I have a total of 104 gal carrying capacity. I can tow from San Fran to SLC, UT on one tank and don't have to worry about fuel or being forced to pull in to small gas stations where it would be extremely difficult for me to fit - it's truck stops only for this guy. Another advantage is that I filled my both my tanks a couple of months ago at $3.64/gal and it should last me until at least the end of summer provided I don't stray too far from home on trips. Aux fuel tanks are pretty popular with owners of big fifth wheels....at least from what I've seen in the last couple of years.

Get 4 golf cart batteries, a quality 3-4kw inverter. Add 2/0 battery cables from the truck's batteries to the rear bumper, add 2/0 cables from the house bank to the front of the trailer, use industrial battery connectors and a self made jumper between the truck and trailer.

But before you start that or a genny you need to know how much current you need and for how long. The inverter and golf cart batteries supplemented with trucks twin alternators ought to do a pretty good job.

Doing this would also circumvent any "no generator" rules.

That's a long run for the 2/0 battery cables. My 2500 watt inverter had parallel #2 and the maximum distance from battery to inverter was 6 feet. Not to mention it doesn't seem too practical to let your truck idle all day tethered to the battery bank while he is in the garage drilling and pulling teeth. He definitely needs a generator.

John

Thanks for all of the info. Do you know of anyone who actually has a diesel genset installed?

Duane, I get a sense that you are telling me "how to" with your tongue firmly in your cheek! The total current draw would not exceed what the output of the standard gas generator would be. The only drawback would be the size of the inverter needed - probably not more than 6kw - and running large gauge cables. Has anyone done this?

newbie said:

That's a long run for the 2/0 battery cables.

Click to expand...

Not really, Have done it or helped do it on 6 different pickups now (twice on my trucks). We use 2/0 to the rear bumper all the time for jumpers, winches and inverters when a genny is not available or impracticable.

newbie said:

My 2500 watt inverter had parallel #2 and the maximum distance from battery to inverter was 6 feet.

Click to expand...

6' from inverter to battery is a long run with 2 gauge. To begin with, with DC your 6’ run is really 12’. Length is measured from the source positive to the device and back to the source negative.

Assuming your 2500 watt inverter could actually output 2500 watts you are exceeding the DC amp load of your 2 gauge.

"Quality" 2 gauge wire up to 10 feet is good for about 150 amps, assuming a max 3% voltage drop. Doubling your leads does not double your capacity, add the two and subtract 30% (average for up to 3 wires bundled). Although in “theory” you might be OK, why not just use the correct gauge to begin with?
And as battery bank voltage drops DC amp load increases.

Using your example W/.85/12.6=DCA
W=AC watts, .85 equals typical inverter efficiency (85%), 12.6 equals fully charged 12 volt battery, DCA = DC amps

2500/.85/12.6 = 233 DC amps load. Drawing 1500 watts (micro, coffee pot etc) will net you about 140 amp draw. As your battery bank starts dropping, which it will using automotive style batteries (even deep cycle) and you will soon be up to 150 amp draw.

newbie said:

Not to mention it doesn't seem too practical to let your truck idle all day tethered to the battery bank while he is in the garage drilling and pulling teeth. He definitely needs a generator.

Click to expand...

There are a variety of variables Roger has not listed. First is, I think the 3010 will be a bit small. The 10’ garage gets small real quick.
How long does he need to supply quality AC power? We don’t know how much current he will need and for how long. 8 hour days – he needs a genny.
He is looking at a Cyclone so I’m figuring he is getting a generator anyway.


3-4 hours? Why not a quality inverter and suitable house bank of batteries. Supplemented by the truck? Using any of the big three’s newest diesels you will have clean, quiet engines, with at least 2 of them capable of high idle control.

He is looking at a Cyclone so I’m figuring he is getting a generator anyway.

RogerO said:

Thanks for all of the info. Do you know of anyone who actually has a diesel genset installed?

Click to expand...

I don’t, but if it was an option I would have “opted” for it? If it would fit I would definitely consider it. And I don’t know if there are any that physical size that are completely enclosed. And you want an RV genny, not some industrial noise monster.

I think I read somewhere the new toy haulers are coming with twin fuel tanks?? That would be ideal for me. Diesel genny on one tank, gasoline for the toys on the other.

Onan does have a genset that, if it fits, would be ideal.
http://www.pplmotorhomes.com/parts/onan-generators/onan-quiet-diesel.htm

6 KW, below National Park noise threshold limits and pure sine wave power. That could be important for your sensitive electrical loads. Older technology gensets ran at either 1800 or 3600 rpm all the time. The newer ones vary the engine speed to the load. No load = lower speed and even quieter noise levels.
I have an Onan 8KW genset in our boat, 2700 hours on it so far and it never missed a beat.

RogerO said:

Duane, I get a sense that you are telling me "how to" with your tongue firmly in your cheek!

Click to expand...

Not at all.

RogerO said:

The total current draw would not exceed what the output of the standard gas generator would be. The only drawback would be the size of the inverter needed - probably not more than 6kw - and running large gauge cables. Has anyone done this?

Click to expand...

If an inverter is an option you will find the practical size limit is 3-4KW with double that for a surge. 3KW draw for any length of time is going to tax your battery supply.

Either way you will be adding to the cost of your rig – and don’t forget you only have one 15 amp duplex in the garage. So you will have to do some electrical in there too.

If I could, and the expense was not an issue:
6 KW Onan diesel genset
3-4KW pure sine inverter
4-8 golf cart batteries (4 is fairly easy, 8 would be a project)
200 watts or so of solar on the roof.
Either a large in frame fuel tank or a bed tank with the ability to pump it to the trailer, either with a portable pump or a pre-piped system.

Something else to consider. Will you be running 5-6000 watts all the time? A 6 KW genset may not be rated for a continuous load at 6 KW.

Most genset rated outputs are at 70-80 degrees and near sea level. Go up in temp or altitude and output starts to drop.

What you are asking is really not that big of a deal, just not common on a recreational trailer forum. Many Class A’ have diesel gensets.

Check this out.
http://www.americanrvcompany.com/assets/images/cumminsonan/a-1408.pdf

Wow, you are really something Duane, thanks!

I plan on having 2 a/c units in the TH, so my major power draw will be when they are both running. As you may know, I plan to use the garage portion of the TH as a dental office, but all of the equipment is portable and very low current draw. So, in reality, my power requirements will be very conservative.

porthole said:

Not really, Have done it or helped do it on 6 different pickups now (twice on my trucks). We use 2/0 to the rear bumper all the time for jumpers, winches and inverters when a genny is not available or impracticable.



6' from inverter to battery is a long run with 2 gauge. To begin with, with DC your 6’ run is really 12’. Length is measured from the source positive to the device and back to the source negative.

Assuming your 2500 watt inverter could actually output 2500 watts you are exceeding the DC amp load of your 2 gauge.

"Quality" 2 gauge wire up to 10 feet is good for about 150 amps, assuming a max 3% voltage drop. Doubling your leads does not double your capacity, add the two and subtract 30% (average for up to 3 wires bundled). Although in “theory” you might be OK, why not just use the correct gauge to begin with?
And as battery bank voltage drops DC amp load increases.

Click to expand...

What I installed (Parallel #2 AWG) is how the inverter is set up and they actually supplied the compression #2 lugs with pins that set screw into the inverter). And doubling your wire does double your ampacity. I have never heard of subtracting 30%.

Anyway, this wasn't something that I just concocted. What I did was right out of the inverter installation manual (parallel #2, maximum 6 foot length).

He is also going a much longer distance than to a winch at the back of the truck. He would need to get to the trailer basement which adds a substantial length to the cable run.

If he is planning on the power consumption necessary for a medical set up in the garage, I think a generator is a must. Batteries are good for dry camping but not something he would want for a professional set up. Also, I would think he would need a PSW inverter which gets pretty pricey when you get up to 3-4000 watt units.

John

Bundling cables decreases capacity.
Curious as the inverter you are using that would suggest parallel cables over a single larger cable.

(parallel #2, maximum 6 foot length). You mentioned that your inverter was 6 feet form the batteries - that makes a 12' foot run with DC.

I certainly wasn't suggesting that the inverter should be mounted in the rear of the trailer, that's a little silly and would require very expensive wire, and totally unnecessary.

RogerO said:

I plan on having 2 a/c units in the TH, so my major power draw will be when they are both running. As you may know, I plan to use the garage portion of the TH as a dental office, but all of the equipment is portable and very low current draw. So, in reality, my power requirements will be very conservative.

Click to expand...

Roger, you could run one AC for awhile on inverter supply but .....................
You really need to sit down and figure out what your loads are going to be.

You will most likely have to add AC electrical circuits in the garage, there is only one outlet.

The 2 A/C's you are planning, is the 2nd unit for the garage? If so yo will have to add all the wiring for that, the garage is not pre-wired for A/C yet.

It is a Vector 2500 watt. Exactly like this

porthole - I suggested to RogerO that he could get the 2nd A/C in the garage after I talked to the factory and they said they could wire back there. Roger also checked with the factory who told him the same thing...so he should be good to go.