What hp tractor needed for 20KW generator requirin

I have a pto gen set, and for me it's the best way to generate power i've found. For light loads i use my compact tractor to power it. For bigger loads i hook it to a bigger tractor!!!

After reading all the answers, i'd like to add, that you are NOT supose to pull more than 80% of your max rated pto power out of your pto for any length of time!!!

With loss', you WILL need 40 pto hp to run a 20 KW get set at max output!! There's no getting around it, you will have loss', and you will need to pull less than 100% out of your pto for cont... duty!!

One more thing, make sure the power shaft is as straight as possible, because the more the bend to the gen set there is, the more the drive line loss' will be!!

Robert

Many listings of generator sets in these magazines stated the KW generator output and the HP rating of the engine running the generator. The HP to KW ratio was most always in the the neighborhood of at least 1.5 engine HP to 1 KW generator output.

Ron's advice was right on. They make special PTO-driven alternators that couple right up to your tractor. They aren't cheap, but if your homemade PTO drive blows up on you, it will sling pieces for a couple hundred yards.

All tractor PTOs operate when the transmission is in neutral, because they're intended to run stationary equipment. Not all PTOs operate when the clutch is disengaged, but most modern tractors have "live" or "independent" PTOs that do.

When you buy the tractor, make sure it has a "live, independent" PTO. Not all do.

I don't see how you are going to do that, as going hydraulic will just be another change of power, and will have more loss' that at the pto.

Robert

At one time I looked for a larger farm tractor, like when your Deutz dealer offered to find one for me. Then I bumped into industrial loaders. Half the price and twice the tractor, compared to farm tractors. No pto, which other than the generator, is no drawback for me. The compact, amazingly, is worth more than the 23k lb Cat.

My dozer has a PTO shaft, at one time i thought of useing that pto to run a gen set, but i'm told the trans in the dozers weren't designed to be used that way. I have tractors, so it's no big deal to get one out when needed.

Robert

As was mentioned in other responses, if the load is inductive or capacitive, this ?quot;reactive?quot; power doesn't register completely; The more reactive, the harder the engine works for a given kw reading.

Your tractor is rated at it's hp at a given rpm. If you increase rpm's and torque holds, you are generating more than spec and also, specs are just that, specs. Each tractor manufactured generates it's own hp which can be significantly above the specified value.

This has been a fun morning. Getting to think.

Mark

While we're on the subject, why did you ask about 3 phase?

Since rpm is an element of the horsepower calculation, increasing rpm's increases hp....if the torque curve is kind to you. Usually though it falls off rather abruptly at high rpms which is why hp curves fall off even though rpm's are going up.

Mark

Regardless of the load, if the tach has an rpm number with a flag on it that says (540 pto)if the tach is on that marker, your pto is spinning at that speed. Doesn't matter the load on the tractor. A load would reduce rpm's and you'd have to adjust the throttle to get it back on the mark.

My generator mostly gets used for powering a large planer and chip blower, 3 motors total 17 hp. I didn't run enough current to that building. For occasional use it works fine. Just want a bigger power source. Already have a couple of big yellow machines with very large hydraulic pumps. Hoping they won't ever have to do much but idle to provide enough flow for the generator. Is that something you know how to predict? Obviously going to have losses with the hydraulic motor.