Generator why aren't pto generators a lot cheaper?

[WilliamBos]

so what.... figure out what load you can pull off it with your BX running it and be happy. If you ever do upgrade youll have plenty of generator to back it up.

Exactly. And who says you have to power everything when the power is down? Just the necessities, nothing more.

 

[have_blue]

Sure wish they'd include the hp spec. on the HF model.

That will be about 1.341 HP per KW.

15KW = ~20hp. There is some inefficiency, so to be safe, 25 PTO HP should pull a 15KW generator head.

 

[WilliamBos]

That will be about 1.341 HP per KW.

15KW = ~20hp. There is some inefficiency, so to be safe, 25 PTO HP should pull a 15KW generator head.

And if the HP cannot pull it, at say 20HP, will the tractor just bog down??

 

[texbaylea]

And if the HP cannot pull it, at say 20HP, will the tractor just bog down??

Will
The tractor will just bog down if you exceed what it is capable of. I have a 7kW unit that I ran behind a 14hp Kubota for many years. I figured I could draw 4-5 kW before loading down the tractor. That was enough to power refrigerator, freezer and a few lights and small fans. As to costs I paid around $1000 for that unit back in 1984 so they have gotten cheaper as the years have gone by.

I still have that unit but need a new control head. The mfg went out of business about 10 yrs ago and the plant is a EPA superfund site.

Anybody on here that can tell me what I need to look for to figure out a new control head. The old one is all potted with a black compound.

Vernon

 

[jake98]

Will
The tractor will just bog down if you exceed what it is capable of. I have a 7kW unit that I ran behind a 14hp Kubota for many years. I figured I could draw 4-5 kW before loading down the tractor. That was enough to power refrigerator, freezer and a few lights and small fans. As to costs I paid around $1000 for that unit back in 1984 so they have gotten cheaper as the years have gone by.

I still have that unit but need a new control head. The mfg went out of business about 10 yrs ago and the plant is a EPA superfund site.

Anybody on here that can tell me what I need to look for to figure out a new control head. The old one is all potted with a black compound.

Vernon

I think fuses have been overlooked here...

I would never hook my tractor to an emergency situatuation (as I've tried to say) Not sure a tractor 'bog down' before the switches are tripping...

I'm no expert here. Jake

 

[jake98]

I'll look at my manual when i get home to see if it shows country of origin.

i know mine is a brushless model, or so it claims.. and it is passive (capacitively) regulated.

soundguy

Like all of them since the 30"s?


ps Why aren't they cheaper?? Give it a little time, they'll (enginless generators) be real cheap. I have a Winco head that I can't pick up, interested? The only thing that's going to be of value is dependability.

 

[J_J]

I did some research about the PTO gen sets a couple of years ago. If I remember right, it stated something about matching up the tractor with the gen set, for this reason. Like someone else mention, if you put a heavy load on the gen set, the rpm of the gen set changes and is not producing the right voltage/frequency. What they eluded to was that on some tractors there is a PTO rpm selection, that is supposed to give 540 at the PTO. Some of the newer tractors have electronic rpm control, so that if a heavy load was placed on the gen set, the rpm would try and decrease, but the engine regulation would keep it at a PTO rpm of 540. They showed graphs and charts how different systems hooked together would work or not work.

 

[jake98]

I did some research about the PTO gen sets a couple of years ago. If I remember right, it stated something about matching up the tractor with the gen set, for this reason. Like someone else mention, if you put a heavy load on the gen set, the rpm of the gen set changes and is not producing the right voltage/frequency. What they eluded to was that on some tractors there is a PTO rpm selection, that is supposed to give 540 at the PTO. Some of the newer tractors have electronic rpm control, so that if a heavy load was placed on the gen set, the rpm would try and decrease, but the engine regulation would keep it at a PTO rpm of 540. They showed graphs and charts how different systems hooked together would work or not work.

JJ, Now you got me doin the 'When I sits and thinks, I thinks...'
Jake

 

[Soundguy]

Rule of thumb is about 2hp per kw generated. yeah sure.. that's not a direct fuel to kw conversion.. but it's a safe one that takes into account reasonable loss thru gearing and driveline. most ptogensets use this rule of thumb.. my 12.5kw unit manual asks for 24pto hp.. etc..

soundguy

I'm getting to the point that I feel some guilt when I buy Chinese stuff.

This HF unit doesn't specify the PTO hp required to pull full amperage on that unit. I know a BX would turn the thing at full RPM with no load, but I wonder how many watts/amps of load could be put on it before it starts to lug down.

The NT gen linked below is 7200 watts spec'd @ 14 hp. and priced @ $900 ($240 more for driveline and you'd need to custom fab a frame) would be a good fit for a BX. I am guessing that the HF unit needs a min. of 29-30 hp to pull that 15,000 watt load.

NorthStar PTO Generator 7200 Watt, 14 HP Required | PTO Generators | Northern Tool + Equipment

Sure wish they'd include the hp spec. on the HF model.

 

[RonMar]

That will be about 1.341 HP per KW.

15KW = ~20hp. There is some inefficiency, so to be safe, 25 PTO HP should pull a 15KW generator head.

1.341 HP per KW is the direct conversion. Sadly it is not even close to the reality of generating electric power. It does not take into account that most engines cannot survive for long at their peak power output levels. It does not take into account drive train and or gearbox losses, or blower loads to move air to keep the generator cool. It also does not take into account that the generator is only about 85-90% efficient at turning torque into kilowatts.

It takes 2HP per KW of electrical load to produce SUSTAINABLE electric power on a small scale. Very large plants(thousands of HP) can typically run at less than this ratio, but not by much. This rule of thumb has been well proven since the creation of the electric generator. You can see it in practice at just about any store or manufacturers website that produce or sell generators. A quality 5KW generator will have at least a 10HP engine attached. If it dosn't, I would question it's ability to deliver a sustained 5KW of electric power...