Anyone here have a PTO generator?

[Lil43]

JB4310
Thanks again for the kind words.The tractor has to be kept at rated pto speed (mine is 2700 engine rpm same as your 4310,not sure about the 1700 but should be similar)unfortantly its not really load dependant but instead a voltage thing,if you let the pto get much below 540 rpm the voltage out really starts to drop fast (as seen on voltmeter on generator) .Your 1700 has 23 pto hp (I use to have a 1600 2 cyl kinda odd sounding things),so you would have no problem with a 7-8000 watt generator,mine requires 24 pto hp for full output so you could run mine.Lastly I cant speak for all of them but mine is 2 pole so mine has a speed increaser that increases the 540 pto to 3600 rpm at generator.

 

[kennyd]

Just a note:

Not only will voltage suffer with reduced RPM, but so will the frequency-measured in Hertz. You must have 60hz or you can damage electronic equipment. A frequency meter as well as a voltage meter are what I consider a "must have" for this type of setup.

 

[Grrrr]

The main problem with tractor driven generators is that they have to be throttled right up to spin the genny fast enough. This means that they are loud. If you can have the tractor away from the house a bit it is OK but if it is close i will get old quick.

I know this because our next door neighbours have an old tractor that spends most of the summer pumping grain from where it is dumped. It is often going all night and is really loud when you are trying to sleep.

If you are lucky enough to have a big tractor with a 1000RPM PTO and enough power to turn the generator at lower revs then it is much quiter.

One guy on here a while ago said he was just going to get an old tractor with just an engine and gearbox and mount that permanently to a generator. That seemed like quite a good idea.

 

[JB4310]

I've never owned a PTO driven implement, but I always wondered why there isn't a gear option for the PTO out put, I know implements like rotary tillers and big brush hogs need alot of power to cut into the ground or be geared up to spin blades, but I would think a diesel powered tractor would have enough torque to turn a generator with out having to operate at near max engine RPM. That's why I started looking at the 4 pole stand alone diesels, they only have to turn 1800 RPM's. the smaller diesels turn at 3600 and are usually air cooled single cylinders, that's fast for a diesel IMO but they have a little better duty cycle rating than the gas burners.

 

[RoyJackson]

Any diesel engine should work well for a generator. Many of the Deere's that have Yanmar engines are using engines that were built for industrial/marine use. Constant RPM at PTO speed would be no problem (still, do check the tractor/engine out on occasions...once every 30-60 minutes).

 

[HD4010]

Hi,

On the question of multi-speed PTOs... I know a guy with a Kubota B7500 and it had a 2 speed PTO. I think it's 540 and 980. He has a 7500 watt PTO generator and was hoping to run it at the 980 gear and be able to run the tractor slower. He said when he first tried it out he had it running at the proper voltage but without a load and everything seemed fine. But then when he applied a load to it, it just about stalled the tractor. So in his case at least, the tractor ran the generator fine at the 540 speed, but at 980 there just wasn't enough power.

Regards...

 

[Mickey_Fx]

I've given thought to building pto drive gensets. Think I start with an ST type generator. They come from China but some brands are of real decent qlty. They're 4-pole design so only need to turn 1800 rpm. They are simple designs with little to go wrong. Intended for 24/7 operation. Have to build your own drive and the final drive and platform might cost you about as much as the gen head itself.

My Yanmar has a 4-sp pto with the top range being 1400-1500 rpm at full speed. For my 24 pto HP and only needing about 7kW, I could build a drive so I could get the 1800 rpm with the engine running about 1200-1400 rpm. Don't seee any reason to need to run full out on the tractor when needing something on the order of 10-12 HP input power. Having to build your own drive you can set it up so the pto could be a lot less than 540 if that is all you have and have plenty of power at lower speed.

 

[Soundguy]

I have a northern tools 12.5kw genny. Using my expensive graphing test meter, freq counter and voltmeter with range hold, I can tell you that my genny puts out cleaner power then my utility provider!

lotsa sizes of genny heads.. from a couple kw on up to 'city sized' 3-phase units... homeowner sizes will fall in the 7, 12, 25 kw ranges.

Tractors are made to run for extended times.. however I see NO NEED to run a genny for continous power.

Powering up your freezer for a couple hours at a time will keep it frozen az long as you don't stand there with the door open gazing in... You can power up your well to get water as needed, and store some.. or to fill your hot water heater... then switch it on.. after it is heated, switch it off and switch the well back on. This provided correct water pressure, and the 60-80 g of hot water is enough for a quick shower, even in a 3-4 person familly.

IE.. no reason to let the thing run just to have 120v setting at an outlet. If you have life support issues.. I'd suggest a whole house dedicated backup genset.

No.. you can't run the tractor at idle.. generator frequency is tied tot he number of poles inthe head and tractor rpm..

In simple terms, The pto gen is just a smaller version of what the power company uses...

Generally, you need about 2hp per generated killowat.. so plan your tractor and genset purchase, if you are going that route.

Northern sells their 13kw for just 1169$.. the 7.2kw is 799.99, and the 27.5kw is 2199.00

PTO Generators | Generators | Northern Tool + Equipment

All 3 provide 120 / 240 outlets..e tc. You will need a pto shaft.. either from northern.. or from TSC.. etc.

I mounted mine on a pallet, then to a 3pt caryall.

Soundguy

I'm thinking about buying a standalone generator ( Honda maybe ) and am wondering how good the pto driven ones are in comparison.

The good standalone ones can be very expensive.

Here are a few questions if anyone can help:

How clean is the power?

What sizes ( wattage output, etc. ) do they come in?

Does it beat on the tractor if you run them for extended times? Like more than 24 hours in some cases for continuous electricity.

Is idle speed enough to run the generator?

How do they operate?

What brands are considered to be of better quality?

And the $64000 question is:

How much do these things cost?

I plan on buying a small tractor in the next year or so and I currently have a small 120VAC generator now but need one with 240VAC.

If anyone has any experience with pto generators for a smaller tractor ( 2520 maybe... ) your input would be much appreciated.

Thanks alot,

LS.

 

[JB4310]

I've given thought to building pto drive gensets. Think I start with an ST type generator. They come from China but some brands are of real decent qlty. They're 4-pole design so only need to turn 1800 rpm. They are simple designs with little to go wrong. Intended for 24/7 operation. Have to build your own drive and the final drive and platform might cost you about as much as the gen head itself.

My Yanmar has a 4-sp pto with the top range being 1400-1500 rpm at full speed. For my 24 pto HP and only needing about 7kW, I could build a drive so I could get the 1800 rpm with the engine running about 1200-1400 rpm. Don't seee any reason to need to run full out on the tractor when needing something on the order of 10-12 HP input power. Having to build your own drive you can set it up so the pto could be a lot less than 540 if that is all you have and have plenty of power at lower speed.

MICKEY_FX, Your thinking along my line,
So does anyone make a stand alone pto gear box that can be coupled in between the tractor and the generator to double the pto output speed? That would make things easier than building from scratch, even if it wasn't doubled, any increase would allow slower engine speed and presumable fuel savings? As well as wear.
But by doing that, would it cut the pto hp rating in half also? Like HD4010 said about the guy he knew that stalled the B7500 using his higher pto speed/gear on a 7500 watter.
As Soundguy stated, if you need about 2 HP for each KW, that's 14 HP for just a 7KW generator then try to get 14 HP from a 32 HP tractor with only maybe 28 HP pto rating then cutting that in half with a gear box, I can see now that's cutting it close. and my idea of doing it with the little Ford 1700 wouldn't work since though I'm not sure, the pto output is probably only around 20 HP.
This is all just an educated guess (using educated very loosely) based on what I've concluded and has been discussed on this post

 

[Mickey_Fx]

Sure have to agree with soundguy about the need to run a gen for long periods. Think having an RV has help teach us how to ration limited power.

About the only time we're out of power is during the winter months. Usually have some indication when a big storm in on the way. What we do is fill the bath tub with water so we have water for the stool and sink. Fill several jugs with drinking water. We can get by without the well for 3-4 days. We have natural gas and wood stove so heating is way down on the list for electrical power requirements.

Few yrs back we were without power for about 5 days. Brought the motorhome up and used the genset to operate the frig and freezers in the garage and run the well pump. Ran the genset for 60-90 min in the morning while getting ready for work and then again for a couple hrs at night during diner and a little time watching the tube. These procedures were more than enough to handle our power needs during the outage.

For shorter periods we can get by with my little 1kW inverter genset. Pellet stove take ~100W, large tv <200W and most of the lighting in the front of the house is by CF. I suspect 500W could take care of us for a couple days without need of the RV genset. The little genset will run at half power for 4-5 hrs in its 3qt gas tank.

I'm not in full agreement with soundguy about power needs. 7.5kW converts to 10HP and even with a 20% loss for the drivetrain that be about 12 HP input and not the 15HP using the 2HP/kW. Not a big thing unless you're on the borderline of available power.

Our modest needs, the frequency of standby power needs and what we currently have has kept me from building something like a pto powered genset of something like 7.5kW.

JB4310, power is power no matter what the speed. Only diff in power requirements between 1800 rmp Vs 3600 rpm for a given amount of power is losses in the drive train.

One issue I don't recall in this discussion is freq stability. A lot depends upon how well the tractor gov controls speed. One advantage of the ST genset is the large rotating mass (armiture weighs about 75# on the 5-7.5kw models) and its ability to handle those short power spikes during electic motor start up. Small low mass designs can't handle those spikes on their own as well, the spike load will transfer the power needs to the engine more quickly.

One reason I favor the ST design is in its simplicity, a set of long wear brushes that takes about 5 min to change out IF needed and large ind std bearings. The brushes only carry field current which is small and brushes can last yrs even under high use conditions. Can repair at home quickly if spares on hand and that ain't going to happend with many/most 3600 gensets especially if of the brushless design. YMMV