Truck PTO generator running welding machines

[xryan]

So, the Bobcat rebate sparked me to ask this which I have been thinking about for a while now:

My interest and wheels have been turning for a long time now and pondering many times getting an engine drive. I don't do a bunch of mobile welding, but sometimes, although except for this past week that's ALL I've been doing 15 stories on the top of portland cement product silo's repairing all their blown out pipe sections...

I would get a Trailblazer 302D that I thought a few times before and almost bought a few when I've seen them come up at auction, I am however interested in the new 325D having excep power, Pulse TIG, etc. However...A/C tig is unavailable and yes I know that the 302D isn't great A/C tig, but it will do in a pinch.

I am putting in an Allison 1000 transmission behind my Cummins Diesel in my Dodge 2500, thereby I will now have a PTO available. SOOO, I've thought about why don't I just install a 1800 RPM generator head and I can run virtually any equipment I want, even my Dynasty 350 at full power on site, I could run an XMT as well. I have more than enough HP available at idle to run a 20KW generator head on a 2.5:1 PTO. I would burn approximately 1/3 gallon at low idle speed, that's pretty **** small and REALLY quiet compared even to a slow speed Pipe Pro or similar 1,000lb HUGE money diesel engine drive.

For that setup I could even just put my shop equipment in my enclosed trailer and run a lead from the truck having onboard single and three phase power for whatever I could imagine.

Am I crazy? Anyone else run a truck PTO generator?

This also leads in figuring how big a PTO generator to mount, something I've always wondered, as I am NO ELECTRICIAN, I just know enough to be dangerous

...all our equipment is rated for a certain amperage draw @ a certain output @ certain duty cycle, etc. However they rarely list the max draw at the max output, just a time delay fuse rating or a slightly higher normal fuse. Also we always have a higher rating available on 3 phase power, but I can get the same power output (at least that's what the LCD tells me) that I can on single phase? I am making that assumption as the manuals for instance with the Dynasty 350 show the volt/amp curve and putting out 340 ish amps at up to 30 volts but don't say whether it is using single or three phase to produce that curve. Is that just because on 3 phase the duty cycle is better in that it is running cooler???

So if I go ahead and install a PTO powered generator head should I use a 3 phase 120/208 unit??

[Broccoli1]

You'll get full power from Single phase- as you mentioned just the duty cycle changes on that machine

[Farmer Boy]

one problem with the pto generator, is the speed of the rotation, one would need a Governor on the engine to get the Frequency correct, and some electrical items are very frequency dependent to work properly,

I would consider an engine driven welder, with a generator in it, most newer engine driven welders produce clean AC power,

and I would think going with a engein driven welder with AC, would be the best. good clean AC power and plenty of weld power if needed, IMO

most generators/ welders will run at either 3600 or 1800 RPM, and my guess is one would need some kind of gearing to speed up the generator, to the proper speed, and then you may be running into a space problem, and I think you would also have a dirt problem, most generators I know of are not sealed up but open so mud and dirt would be being kicked up into the winding and rotor. unless this unit is specialty designed for this application,

[lars66]

There is an outfit that makes a pto generator set up for trucks but I can't remember the name right now.

[Meltedmetal]

Like these ones?

http://realacpower.com/

[xryan]

You missed the whole point. I can run any machine I want straight off a PTO generator head. No, welder/generators can not supply half the power I can make off the PTO. I'd rather not spend money buying another welder when I don't need one, or lug around 1,000lbs and take up 1/3 of my bed space. RPM can be controlled to single digit increments for proper Hz. There are a million and 1 drive ratios and speed increaser or reducer gearboxes to match to an 1800rpm generator head. There is no issue with space. If you are not familiar with PTO operation, please don't pontificate.<br />
<br />
RealACpower has a very limited offering at an inflated price.

[Meltedmetal]

I'd be surprised if your diesel has the power to run a 20 kw generator(delivering anything close to 20 kw) at low idle and stay running. And isn't it bad for a diesel to run for long periods at low idle anyway? All mine basically say kick it up or shut it off.

[lars66]

Like these ones?
http://realacpower.com/

Yup that is the one I had in mind.

[cruizer]

Interesting idea, kinda pricey though if not used much. I'd also want to know how much the unit can surge. When you strike an arc, the input will surge. Line transformers will handle it through large Capacitors, engine driven through a Governor. The Real Power is an unknown. It does have a tolerance for Motors starting. that said, the drives for the motors have built in smoothing. Plus there is nothing available for the PTO's on Dodges.

[welderboyjk]

http://www.fabcopower.com/generat/HYGENINTRO.htm

[welderboyjk]

http://www.vanair.com/index.php/generators.html

[JTMcC]

No, welder/generators can not supply half the power I can make off the PTO.

May be.
My machine (quietly) makes 19k 3 phase. That's plenty for me.

[xryan]

I'd be surprised if your diesel has the power to run a 20 kw generator(delivering anything close to 20 kw) at low idle and stay running. And isn't it bad for a diesel to run for long periods at low idle anyway? All mine basically say kick it up or shut it off.

We're talking about a 5.9 Cummins, it outputs over 100hp even at low idle. Factory motors can be run approximately 205HP output capacity 100% duty cycle. That's a LOT of KW's...

Low idle 750 RPM
High Idle (cold ambient temp) 1000 RPM
PTO Idle (factory) 1100-1500 RPM adjustable in 100 RPM increments with cruise control buttons
Reality you can have 750 to whatever RPM you want in very small RPM increments with stand alone PTO controller.

Interesting idea, kinda pricey though if not used much. I'd also want to know how much the unit can surge. When you strike an arc, the input will surge. Line transformers will handle it through large Capacitors, engine driven through a Governor. The Real Power is an unknown. It does have a tolerance for Motors starting. that said, the drives for the motors have built in smoothing. Plus there is nothing available for the PTO's on Dodges.

I don't know how adding a generator head and PTO takeoff is more pricy than a $5,000 - $10,000+ engine drive that gets infrequently used and weighs 750-1200lbs taking up 1/3 of the bed space. The Real Power brand is just that, a generator head, just like the other dozen or so factory PTO generators available for a myriad of truck/transmission brands or running on a engine drive generator. I'm talking about just running the generator head and pluggin in whatever welder power source I want just like in the shop just "wireless."

BTW there a LOTS of PTO options for Dodges, most "factory" upfitters are designed for manual trans 3500, 4500 and 5500 pickups and cab/chassis models. In reality there really are none that you can't add a PTO drive to with either a PTO transfercase plate or swapping a transmission with a PTO output like I am doing.

My machine (quietly) makes 19k 3 phase. That's plenty for me.

I bet a 5.9 cummins at 750-1000rpm is a WHOLE LOT quieter. What engine drive are you using and how much does the monster weigh to output 19kw?

[JTMcC]

I bet a 5.9 cummins at 750-1000rpm is a WHOLE LOT quieter. What engine drive are you using and how much does the monster weigh to output 19kw?

My machine is a lot quieter than the Cummins in my truck.

It's not a "monster", good grief, it's just a regular engine drive welding machine. A Vantage 400, it weighs around 1100 LB.

[Kpack]

I've been reading this thread and doing some searching . It looks like your gph on fuel will be high with the Pto on a truck.