PTO generators -- anybody have any experience/suggestions?
 

I'm looking at various PTO driven generators to run off my 540 rpm, 40 hp diesel tractor. I want to be able to run central A/C, two freezers and a fridge also household lighting.

Comments?

Make sure you twist the belt when you install it. It will last twice as long.

Anyone who sells these generators should be able to describe this to you. I would bet you would already know this, but if you didn't it is an important part of running a generator off a PTO.

Twist the belt? I've never seen a PTO generator that was belt equipped.

I have a 12K PTO generator that I've used for backup power, its the one sold by Northern tools.

NorthStar PTO Generator — 13,000 Surge Watts, 12,000 Rated Watts, 24 HP Required | PTO Generators| Northern Tool + Equipment

I bought mine used a couple of years ago with a broken 3 point mounting frame for, as I recall, around 1K dollars. I repaired the frame and it works fine but after a few years I decided I'd rather have a dedicated generator so it's been sitting in the shop unused for a couple of years. PM me if you're interested, I'd be willing to sell it.

Here are my observations.

The good - no extra generator engines to maintain, minimal storage footprint when not in use, fairly easy to hookup, easy to use, gives you the ability to have power in remote locations. I've used a MIG welder a couple of times off the PTO generator in places where power wasn't available and it gives you a nice capability to repair things in-situ in the field.

The bad - using a 40hp tractor to produce a couple HP of power. Fuel economy isn't stellar compared to a smaller dedicated generator. Its also pretty loud in operation, the tractor is running at 2600RPM and because the gearbox in the PTO generator is a 3:1 step-up there is a fair amount of gear whine noise. Its not something I'd want to have running 20 yards from my house at night. If its going to be raining when you're using it (and since hurricanes are mostly when I use mine) you need to be able to park the tractor/generator in a semi-sheltered area when its operating. There may be other units that are more water-poof but the Northern Tools unit isn't rated to be outdoors in weather. It takes longer to bring the generator into service since you have to un-mount whatever you have currently have installed on the 3 point mount and remount the generator. Of course you can mount the generator before the storm hits based on weather forecasts....in my case this was always a sure-fire way to ensure that I never lost power in the storm. PTO's in operation are always a bit hazardous, I live in a fairly rural area but I was always slightly worried about some kid hearing my tractor running and coming over to investigate and getting his coat caught up in the PTO shaft. I'm sure a lawyer would have a field-day with this scenario.

I went the PTO direction because I wanted the ability to run A/C, I don't live in Louisiana so after a few year I decided that I'd give up that capability and go with a much smaller generator that can power my well pump, lights, refrigeration, ect.
I'm happy with my decision but if A/C was an absolute requirement I'd have stuck with the PTO set-up since generators powerful enough to reliable operate central A/C systems are pretty pricey.

I was able to operate one 4 ton central A/C unit fairly easily with my 12K PTO generator. The rule of thumb is 2HP per KW so your 40 HP tractor could power something in the 20KW range.

I want a generator powered by a steam engine.

That is really useful to know - I'll try and remember that.

Thanks for the detailed response, Tim. That's really helpful.

I live in a very rural area and like you, hurricanes are the primary hazard. I have a 83 yr-old mother-in-law that suffers in the high heat and humidity so A/C is a must.

Running the welder off the generator is another thing I was planning. But DC stick rather than mig. It gets pretty windy.

The fear of some kid getting wrapped around the pto is a horrible thought and could be a show-stopper. I'll ask my lawyer what I can do to mitigate.

The carport is large enough for the tractor & generator. Don't need to worry about weather.

I think shipping from DE would be prohibitive, but I looked at the generators at Northern and they sure looked promising. I can fabricate my own 3pt hitch and rack for the generator. Now you got me thinking about an expanded metal cage around the pto.

For safety:

1. The generator should be bolted to the tractor (3pt is great)
2. Plastic PTO shaft freewheeling shield
3. Bent & welded cattle/goat/whatever panel to guard the whole assembly

Makes sense and fairly simple.

All my PTO driveshafts have the plastic covers in place. They are a pain in the ass when connecting driveshafts but I think the safety factor they add is significant. BTW kids aren't the only hazard, for some strange reason my dog doesn't seem to be afraid of the tractor/generator when its in operation? If a shotgun does off 600 yards from the house she comes running over to me but she seems totally unfazed with the screaming tractor/generator package. Go figure.

How are you planning on interfacing the PTO generator into the house wiring?

There is a code issue with generators and interfacing them into house wiring associated with 'neutral-bonding', do a search for more info. it's kind of a subtle issue but there are very real safety concerns if mistakes are made.

We used an old Chevy truck. Jack the rear of the truck off the ground or use a winch on the rear bumper to suspend it from a tree branch, then, with one rear wheel locked in place and the other rear wheel running a steel wheel with no tire, remove the bed and you have a great PTO.

Tie the generator to a large tree with a rope and a block and tackle, put another bare steel wheel on the end of it by cutting off an axle to mount the wheel on, coupling the axle to the generator with a spider type coupling (We used an old Mercedes flex disc! Nothing but the best!) Hook them together with a canvas belt with a twist so one side does not do all the work and then tell everyone to stand clear or suffer the results.

You could also just use a gas engine to run the generator, but we had the old truck and didn't want to buy a stationary engine.

That and we had some time on our hands. I think a lot of booze was also involved.

This solution is straight from the 30s. (Dangerous but resourceful)

Few things scare me more than the old belt PTOs

That's the easiest part! I have friend who is a licensed electrician. Done.

Oh yeah, don't waste money on a transfer panel-just buy an interlock kit. They're typically $20-$50 and are sliiiick