10Kw generator powered by JD332 garden tractor

[Industrial Toys]

Even a 3.5 HP push mower has a governor.

 

[RoyKing]

I miss spoke let's take an example the governor on vanguard twin generator looks nothing the governor on my vanguard ride on mower of the same horse power, I was planning on trying the same thing.

 

[DanMc77]

Wow, great to see so much input on this.

I'll add some detail of what I need to accomplish with this: We have an off-grid camp up in NH and only need a big generator every now and then. So rather than have a big generator sitting there getting gummed up sitting idle, this can sit for a year or more with no use and be pulled out as needed. It will take up very little storage space, and I already have the tractor there for mowing. It will be about a 5 minute job to switch from mowing to getting the generator installed.
The beauty of the diesel is the stability of the RPM under load. The governor is very stable and the diesel just chugs along with lots of torque.
The router was not under load, so when I wanted more load I added the welder. That's when I could see that I need a larger pulley. I don't think that I'll really need the full capacity out of this unit, so I just need to be able to carry what I need. I want to keep the engine running at a moderate speed for fuel efficiency, yet fast enough to support whatever load I need. It's nice that I can go with a larger pulley on the generator and speed up the engine to get more power if I find that it's needed. Next step is to put on the 4" pulley, add a real belt tensioner, and then go looking for more stuff to load it up with.
I got this 332 last summer because I wanted a machine that holds its RPM better when running the snowblower attachment. The JD 332 is a 16 hp diesel, but it has more torque than the 18 HP gas JD 318 that it replaced, so the RPM is very stable under load. With just a little load the gas engine starts dropping RPM right away. The diesel just chugs along.

 

[DanMc77]

I miss spoke let's take an example the governor on vanguard twin generator looks nothing the governor on my vanguard ride on mower of the same horse power, I was planning on trying the same thing.

It's possible the governor on a generator is designed to hold RPM much more accurately than your typical mower.

 

[Industrial Toys]

Any more sophisicated generator will use an electronic governor, like from Governors of America. They are nice, because they also allow idle, warmup speeed and cool down modes.

 

[texasranger556]

If you use a split taper or QD style pulley it would be simple enough to have a big pulley and small pulley and corresponding belts for a high power mode and low power fuel economy mode. Or if the shaft is long enough install both size pulleys at once and design the mount to slide in or out an inch or so to align the pulley you want to use. Still need 2 belts or extra long travel on the tensioner.

 

[Tractor Seabee]

Wow, great to see so much input on this.

I'll add some detail of what I need to accomplish with this: We have an off-grid camp up in NH and only need a big generator every now and then. So rather than have a big generator sitting there getting gummed up sitting idle, this can sit for a year or more with no use and be pulled out as needed. It will take up very little storage space, and I already have the tractor there for mowing. It will be about a 5 minute job to switch from mowing to getting the generator installed.
The beauty of the diesel is the stability of the RPM under load. The governor is very stable and the diesel just chugs along with lots of torque.
The router was not under load, so when I wanted more load I added the welder. That's when I could see that I need a larger pulley. I don't think that I'll really need the full capacity out of this unit, so I just need to be able to carry what I need. I want to keep the engine running at a moderate speed for fuel efficiency, yet fast enough to support whatever load I need. It's nice that I can go with a larger pulley on the generator and speed up the engine to get more power if I find that it's needed. Next step is to put on the 4" pulley, add a real belt tensioner, and then go looking for more stuff to load it up with.
I got this 332 last summer because I wanted a machine that holds its RPM better when running the snowblower attachment. The JD 332 is a 16 hp diesel, but it has more torque than the 18 HP gas JD 318 that it replaced, so the RPM is very stable under load. With just a little load the gas engine starts dropping RPM right away. The diesel just chugs along.

This seems to be overlooked, you need the full 3600 RPM to maintain 60 cycle power and 120/240 volts. Some things are not sensitive to out of spec power some are not, motors especially not. Less than 100 volts will cause problems with most appliances and lights will dim significantly.

Ron

 

[Dave M7040]

An almost always overlooked aspect of these projects is the importance of knowing and understanding the engine's torque curve as you select the rpm and pulley ratios to power the gen head.

This may be something you already know and if so, sorry for wasting your time.

Companies who mate generators to engines know that they need to have the system running at the engine rpm's just past the peak of the torque curve. The reason for this becomes obvious if you give it a little thought.

As a load is applied to the generator, the tendency is to slow down. If you are starting out running past the torque peak, as the rpm's drop, the torque available actually increases and the generator is much better able to respond to the increased load while maintaining rpm's close to your design goal.

If you are running before the peak of the torque curve and apply a load to the generator, as the speed drops, so does the available torque and you can end up with a sudden stall.

The engine maker's web sites usually have torque curves for their products. The importance of torque over horsepower is shown on newer walk behind snow blowers. No longer do their engines have horsepower labels but rather torque figures.

You are on the right track, just pay addition to the small but important issues.

Dave M7040

 

[DanMc77]

DaveM, thanks for the insight on the engine torque curve. It makes a lot of sense that for the max output, you probably want the engine running at an RPM above the peak so it picks up torque as it loads up. If anybody has the torque curve for the little Yanmar in the JD 332 tractor, that would be good to see.

Last night I had a chance to power up the generator using the 4" pulley. The engine now runs at about 1950 RPM to get 3600 on the generator, which is a nice improvement. I found that when the meters are reading 120 volts, then the generator is spinning at about 3600. I'm going to wire up my 13" 2hp Jet planer to run a serious 220 volt load and see what happens. My gut feel is that it will struggle when the planer is running with a load.
Considering how easy it is to mount, I'll keep a selection of pulleys to use depending upon what kind of load I want to run. The experimentation and learning is half of the fun.

 

[Dave M7040]

DaveM, thanks for the insight on the engine torque curve. It makes a lot of sense that for the max output, you probably want the engine running at an RPM above the peak so it picks up torque as it loads up. If anybody has the torque curve for the little Yanmar in the JD 332 tractor, that would be good to see.

Last night I had a chance to power up the generator using the 4" pulley. The engine now runs at about 1950 RPM to get 3600 on the generator, which is a nice improvement. I found that when the meters are reading 120 volts, then the generator is spinning at about 3600. I'm going to wire up my 13" 2hp Jet planer to run a serious 220 volt load and see what happens. My gut feel is that it will struggle when the planer is running with a load.
Considering how easy it is to mount, I'll keep a selection of pulleys to use depending upon what kind of load I want to run. The experimentation and learning is half of the fun.

Dan
If you provide the Yanmar model number, i will look for a torque curve.

I would suggest you start loading your generator with resisitive loads rather than inductive loads to start with.

Resistive loads are electric heaters, kettles, toasters.
Inductive loads are motor loads. These are much harder to start. I would hate to see you damage your stuff starting with a big inductive load.
Often, when people are trying to power an AC for example, they need to be using kits, often called "soft start kits," which uses capacitors to sort of cancel out the inductive motor loads.

For the motor loads, start with small ones. A blender or corded electric drill come to mind.
I destroyed by Honda generator with a "Skill Saw." I was trying to trim something and was triggering it off and on and suddenly it was dead. The rotor had a short.

Dave M7040