PTO driven generator

[Soundguy]

Pretty sure his phone auto corrected PTO to pro. So it would be the continuous PTO HP rating (as opposed to the peak PTO HP rating that it can only do for a little bit).

Aaron Z

Yes thanks. ^%%# phone.

 

[Soundguy]

Tractor should be able to run pto hp. Without losing rpm. All day every day.

exactly... it should be able to make its rated P T O hp all day, etc.

 

[Soundguy]

The 2HP per KW is a rough rule of thumb to leave some inrush starting capacity and not not operate the tractor at absolute max.
746 watts per HP. Allowing for some mechanical , magnetic, windage, etc losses. 1-1/2 HP shaft HP will
Produce 1KW. With no reserve for intermittent overloads or motor starting. Some tractors are border line for overheating at max continuous power. In particular with the usual clod of oily mud half blocking the middle fins.

most pto generator sellers I see advertise that they want you to be closer to that 2hp perk generated KW.

sure we all know the physical conversion is at 746.. but that is on paper, not inthe field with a spinning shaft and puffing smoke stack.

using the 2hp # is quite safe, and sure.. you probably do better, especially on incremental incandescent loads so you can creep up to max.. vs hitting the system with 8kw inrush motor start loads now and then.. even if they do level off to 2kw running, etc..

on a pto gen and tractor.. you deffinately want some slack built in, especially if dealing with large motor loads.

 

[Soundguy]

MY experience with the several compacts I've owned is, if you run them near, or at MAX, they will over heat something no matter how clean the rad ect. is... They just don't have the built in reserve of a farm tractor.

One Kubota I had, I rotary cut a field that had HEAVY grass in it. It took several hours to get it done and although the gage got "near" the red, it never touched or got into it. The rad never boiled or showed over heating, but I'm sure it burned/warped the valve guides!

SR

All I can say is if you experienced overheating with a tractor running at rated pto hp, and the unit was maintained properly, then it was junk.. IMHO.

Before I got power to my farm, a left an old 1955 ford 660 tending my well, and running some lighting, welder and power tools for fencing and animal structures.

that tractor ran all day, many days sometimes..back then, that was a 53 year old tractor at that point. not a spring chicken.....

 

[Fallon]

You'd be fine running a 20kw behind that smaller Yanmar. The problem is the load applied to the generator, not the rating of the generator.

A 20kw generator & an 8kw generator will take the same HP to generate 7kw of power.

From that point of view I'd rather have a bigger generator than a smaller one. You'd be running it at a lesser percentage of its max increasing its lifespan & decreasing the chances of overloading something on the generator. Also a bigger generator will have a bigger rotor for a better flywheel when dealing with load spikes.

 

[Soundguy]

Correct, mechanical load is based on electrical load, its just perhaps a tad wastefull and expensive to buy 2-3x more Genny than you have ponies in the corral

 

[Sawyer Rob]

Correct, mechanical load is based on electrical load, its just perhaps a tad wastefull and expensive to buy 2-3x more Genny than you have ponies in the corral

Then again, you may increase the herd in the future, and buy a "horse" instead of another pony.

Fallon has nailed it, with his answer...

I run my 15KW gen set with a 12.5 pto hp "pony" quite often, I just never pull more than 6KW from the gen set. IF I need to pull more KW, then I put a "horse" in front of it. lol

SR

 

[Soundguy]

Then again, you may increase the herd in the future, and buy a "horse" instead of another pony.

Fallon has nailed it, with his answer...

I run my 15KW gen set with a 12.5 pto hp "pony" quite often, I just never pull more than 6KW from the gen set. IF I need to pull more KW, then I put a "horse" in front of it. lol

SR

My 12.5kw genset has had 4 tractors in front of it ( all fords/NH ). an 8n ( 27ish pto hp ) a 660 ( 32ish pto hp ) a 5000 ( 67ish pto hp ) and a 7610s ( 90ish pto hp ).

Loads up to 8kw hitting the 8n or 660 you could hear the engine load up a bit to compensate. 8kw hitting the 5000 and the 7610s seemingly had no effect. or at least no detectable one due to the extra big flywheel and quite excessive amount of ponies )

 

[buickanddeere]

It's difficult to operate a small generator at 100% load. Panels tend to be unbalanced. a 10KW generator may have a 10Kw load on it. However one 120V line maybe loaded with 6Kw and the other 120v line loaded with 6Kw.
As I have said before after observing all manner of generators from small to large. Best not to load a generator 'rated" for 10Kw continuous with more than about 8Kw actual continuous.
" over sizing" a generator reduces winding heat, improves voltage regulation and improves reliability and lifespan.