Picked up half a megawatt worth of Caterpillar power, think I'll make a PTO generator

[strantor]

1 hp = 745 watts

210 kw = 283 hp

your ls has 32 pto hp??

these heads may be 460 volt 3 phase? seems like a large problem to get this to work on your tractor....

you may not even have enough HP to excite the winding.

looks like the sr4b is usually paired with a ~500 hp 3456 ....

210kw is a huge head. I bet its 3phase also. Good luck being able to turn that thing fast enough with 30hp and 540rpm

These heads are 12-wire configuration which means they can be connected Wye or Delta, high voltage or low voltage, single phase or 3 phase.

The excitation power is 60V @ 12A, just about 1HP.
There will be brush resistance, bearing resistance, plus the drag of spinning the internal cooling fan. I'm thinking somewhere in the neighborhood of 5-10hp just to spin the rotor and make voltage with no electrical load. That should leave plenty of PTO power left over to power the house.

Just because the generator can put out 283 electrical HP, doesn't mean it has to, and doesn't mean I need to pair it up with a prime mover capable of 283 - 500 mechanical HP.

Theoretically I could spin this thing up with a little 5hp Briggs lawnmower engine for testing. That massive rotor has a lot of inertia so It would probably take a minute to get up to speed, but should work. The tractor might even have a hard time getting it up to 1800rpm in the beginning, but once at speed should be able to handle any household load I throw at it, and that juggernaut of a rotor should help to smooth out any hiccups caused by instant high loads, like the central A/C startup.

 

[MossRoad]

Those straight 6 engines might produce around 150hp. Following the 2hp = 1kw example from the link, you'll be running that 210KW generator and be lucky to get 70kw out of it.... which is a stink-load for a house! :laughing: But you'll also be running that engine at higher RPMs and consuming a lot of fuel, too.

And then you have the 3phase issues to work out, and all associated wiring, etc....

Still, looks like it could be a fun project.

 

[thekkfan]

I thought about this route a long time ago. Ruled it out because I didn't like the idea of tying up the tractor during a power outage- outage that I would VERY LIKELY need the tractor for clearing trees, etc.

Ended up buying a 13k portable unit dedicated to the house. But I CAN move it somewhere else on the farm if needed.

Look forward to seeing your adventure unfold!

 

[Industrial Toys]

Nice sets, if you need to power the Res. All those Nintendo games!

I bet my little Onan/Kubota 7.5 that is my main set at the moment wouldn't have the balls to drive the cooling fan on one of those. And 7.5 is way over kill in the summer with just a fridge, freezer and a couple of light bulbs going. BIG is nice, but wet stacking isn't nor burning unecessary fuel.

I just got a friend 100kw Onan/Allis Chalmers 6 cyl Diesel. He just bought it for the engine, for the same reasons I mentioned above.

 

[strantor]

Those straight 6 engines might produce around 150hp. Following the 2hp = 1kw example from the link, you'll be running that 210KW generator and be lucky to get 70kw out of it.... which is a stink-load for a house! :laughing: But you'll also be running that engine at higher RPMs and consuming a lot of fuel, too.

And then you have the 3phase issues to work out, and all associated wiring, etc....

Still, looks like it could be a fun project.

It wasn't me who mentioned a straight 6. That was other people's suggestion. I'll be powering it from my tractor PTO which is 31hp. Following the thumb rule, I'll have 15Kw available which should be sufficient for the house. Later if I couple one of them to the 80hp forklift motor I have, then 40kW would be even cooler.

Either way, there will be potential 170-195kW that I can't (and don't need to) tap into. I expect that these heads will probably outlive my kids, having only ever been run occasionally at 10% or less of their rated load. I could probably remove the power-sapping cooling fan actually.

 

[strantor]

I thought about this route a long time ago. Ruled it out because I didn't like the idea of tying up the tractor during a power outage- outage that I would VERY LIKELY need the tractor for clearing trees, etc.

Ended up buying a 13k portable unit dedicated to the house. But I CAN move it somewhere else on the farm if needed.

Look forward to seeing your adventure unfold!

Yeah I don't like the idea of tying the tractor up either. PTO power is the immediate goal, but long term contingency plan. Long term goal is to have it coupled to the forklift motor, but still able to couple to PTO if the motor craps out.

 

[Industrial Toys]

I used to run a 15KW Onan PTO set with my JD 770 tractor. 21 HP or so. The outfit worked great. I once turned on all the baseboard heat and all stove elements and could not kill it. THEN, I put in a 2:1 gearbox, and the tractor would not even turn that thing evenly without any load. I did not expect that. BIG disappointment.

 

[Sawyer Rob]

In all the times I've run my pto generator, I've not once needed a tractor for "something else"... Think about it, how many times when the power has gone out, have you had to run out the door and jump on the tractor?

If needed, NO reason the gen set couldn't be shut down for a few hours each day to take care of "other things" to use the tractor for...

To the OP, the biggest problem I see is, the amount of fuel that little tractor is going to drink, powering that big gen head. Plus, adding another gear box? Even more loss'.

Fuel consumption is by far MY biggest worry in a power outage, I could run out and not beable to get more? The other thing is, who wants to pay, 10, 15 or even more per HOUR just to have electricity?

NO one in this house is that spoiled, that it's worth it, to pay that price, just for juice!!

SR

 

[thekkfan]

In all the times I've run my pto generator, I've not once needed a tractor for "something else"... Think about it, how many times when the power has gone out, have you had to run out the door and jump on the tractor?

If needed, NO reason the gen set couldn't be shut down for a few hours each day to take care of "other things" to use the tractor for...

You apparently need a few horses or cows depending upon you while fixing a fence from trees down while power is out. Just like I had couple weeks ago with Michael. Automatic waterers don't work when well pumps don't run. And you cant use loader to move trees off fences if it's tied to a generator. If ice storm is the problem, I'd rather not have my house cold when I return from fixing same issues as above.

It may not be needed in two places at once on your farm, but it is on some people's property.

 

[MossRoad]

Winter storms is a good example of when you might want your power on in your house while you're using your machine to clear the snow.

Another is storm damage cleanup.