Generator PTO vs Gas Engine Generator

[RoyJackson]

twist the 3pt arms? really? 3pt arms size will be compariable to pto hp.. IE.. more pto hp = bigger tractor = bigger arms. thus if your pto genny and thus laod will be sized for your tractor.

whoever told you it will twist the 3pt arms off must have ever actually used one.

I have read the trailer type (the ones not connected to the 3PH) can rotate from the PTO torque if not bolted down to the trailer.

 

[joshuabardwell]

One theory I've heard is that the torque will twist or rotate the 3-pt arms.

The three-point arms are made to hold an implement that is being run on the PTO. How much torque do you think a tiller puts on the arms? What good would the PTO be if it was capable of torquing off the three-point arms?!

 

[joshuabardwell]

Regarding the PTO generators, does the PTO have to be run at 540RPM?

Or, can you run the tractor at less than 540 if you don't need the full load? For instance, if I have a PTO generator that puts out 10kw continuous at 540, can I run it at say half that if I only need 5kw? Or does it have to be run at 540 to keep a constant 60hz or something?

It must be run at 540 to keep a constant 60 Hz, exactly. What will happen as the load increases is the governor will have to give the engine more fuel to keep the motor running at 540 rpms, so your fuel consumption will go up as your electrical load goes up, but your engine RPMs must remain constant.

The exact PTO RPM to produce 60 Hz will vary slightly from unit to unit. Most, if not all, have a display that shows the voltage and frequency, and you use that to set your RPMs to whatever produces the right values.

 

[Piston]

It must be run at 540 to keep a constant 60 Hz, exactly. What will happen as the load increases is the governor will have to give the engine more fuel to keep the motor running at 540 rpms, so your fuel consumption will go up as your electrical load goes up, but your engine RPMs must remain constant.

I'm not sure if I have a governer? I believe that when I put a load on my tractor at 540, the RPM's will drop, the will only come back up to 540 if I give it more throttle, or reduce the load. Although, I haven't really paid attention to whether or not it truly is 'governed' because I never thought twice about it.

 

[dex3361]

I'm not sure if I have a governer? I believe that when I put a load on my tractor at 540, the RPM's will drop, the will only come back up to 540 if I give it more throttle, or reduce the load. Although, I haven't really paid attention to whether or not it truly is 'governed' because I never thought twice about it.

If your talking about the tractor you have listed the Kubota L4610 has a governer and will doa great job spinning a generator. What I do on my L4400 is adjust the frequency to 61 hz no load and when a load is applied it settles at 60 hz and holds steady. The PTO is right at the 540rpm speed.

 

[Soundguy]

I have read the trailer type (the ones not connected to the 3PH) can rotate from the PTO torque if not bolted down to the trailer.

yes.. if the pto gen is setting their naked and not attached to something. it WILL try to spin over with even a light load.

I don't like the trailer ones as they don't seem stable. the cary-all 3pt mounted ones are rock solid.

Plus.. I have had that rig setup with my arc welder on the pallate too.. and been able to drive around my farm and weld up gates.. and run pole saws and drills and whatnot. good mobile work platform.. and you can backup easy with it.. and trailer it.. unlike a lil 10cf trailer like many are built around.. load that on a deckover equipmetn trailer... easy with a caryall.. NOT EASY wit the lil trailer!

 

[Soundguy]

I'm not sure if I have a governer? I believe that when I put a load on my tractor at 540, the RPM's will drop, the will only come back up to 540 if I give it more throttle, or reduce the load. Although, I haven't really paid attention to whether or not it truly is 'governed' because I never thought twice about it.

yes you do.. it's built into the injector pump.

it's not infinite mind you.. it has a limited range.. etc.

 

[Piston]

Thanks Soundguy and dex, for clearing up the governer thing for me. It sounds like I might be more interested in a PTO generator after all I'm having a transfer switch installed next week in my home and have been reading up on some of these threads for some advice. I haven't had to ask too many questions as I've learned a lot just from what's already been posted.

 

[Soundguy]

if you have a tractor.. a pto gen is cheaper wattage and yer tractor is likely way more engineered than the lawnmower engine running the genset.

downside is you can't laod the pto gen into the trunk and take it camping.. etc. ( but you can get an inverter.. )

 

[Piston]

downside is you can't laod the pto gen into the trunk and take it camping..

That's okay, camping and generators don't mix anyways...

 

[Soundguy]

inverter nice and quite though.. hungry.. but quiet.. could double as a heater on a cold night..

 

[megaboz]

The three-point arms are made to hold an implement that is being run on the PTO. How much torque do you think a tiller puts on the arms? What good would the PTO be if it was capable of torquing off the three-point arms?!

My interpretation of the twist is the play that in the 3 point arms and the top link.

I know when I first fire up my brush hog it does move the 3 points a bit on initial engagement.

 

[RoyJackson]

My interpretation of the twist is the play that in the 3 point arms and the top link.

I know when I first fire up my brush hog it does move the 3 points a bit on initial engagement.

Yep, torque is torque...but twisting or breaking the lower link arms isn't going to happen...
Now, a caveat..if an idiot hooked a subcut PTO up to a Cat 3 cutter, something could break.

 

[zzvyb6]

I have read the trailer type (the ones not connected to the 3PH) can rotate from the PTO torque if not bolted down to the trailer.

That is 'theoretically possible if you are starting to power up a small department store with a very large freezer section (or lets say a grain dryer to be realistic). When you throw the breaker to engage the load, the emf retarding torque can be large. On a home, that could be because the furnace is out, the well is out, all your electronics chargers are on, and you might have forgotten to throw the mains. But, a single hitch on the drawbar won't resist this torque. The trailer axle width does. My 50kw has breakers on the 3 phase taps, the single phase 220 output stove plug, the genny field coils and the 120v convenience outlet. The breakers will open before the torque gets large enough.

On my diesel F935 hookup, I don't even bother with the tongue attachment. The only thing you would notice is the motor governor burping when all this demand is encountered. All the gen-set waxers would probably want to carefully engage each panel breaker one at a time until they have enough stuff working in the house. Otherwise the tires might get dirty when she digs in. If this happens at night, the neighbors might discover it before you do and the subdivision newsletter report could make you the laughing stock of the 'hood. OMG....

 

[megaboz]

Yep, torque is torque...but twisting or breaking the lower link arms isn't going to happen...
Now, a caveat..if an idiot hooked a subcut PTO up to a Cat 3 cutter, something could break.

Yea I know it wouldn't break them, but the play will let it shift some. That's what I thought the question was about. Wouldn't that cause issues? My thinking that it could cause some, probably minor, frequency variations for a brief period. Probably not something to worry about.

 

[Soundguy]

Yea I know it wouldn't break them, but the play will let it shift some. That's what I thought the question was about. Wouldn't that cause issues? My thinking that it could cause some, probably minor, frequency variations for a brief period. Probably not something to worry about.

sounds like the 3pt doesn't have well adjusted stabilizers, or toplink.. and/or the lower 3pt lift arm balls are loose.

On my 660 and 8n.. both have stabilizer bars on each sid eof the 3pt, plus stay bars.. plus toplink.. and all ball ends are good.


when i start up the genny, under load.. the engine hits for a sec as the gov picks it up.. then it's off and running.

no jiggle / jangle play back there.

IMHO.. that much play back there will beat the tractor up if you have a real implement on it swinging and beating around back there.

sounds like some people need to address their rear hitch?

 

[megaboz]

Could be. I was just pointing out that whole 3 point question may have been about the play in the 3 point.

 

[RoyJackson]

Yea I know it wouldn't break them, but the play will let it shift some. That's what I thought the question was about. Wouldn't that cause issues? My thinking that it could cause some, probably minor, frequency variations for a brief period. Probably not something to worry about.

Yep, probably not something to worry about...there's nothing on the 3PH that is made so precisely or delicately that you'd see appreciable wear for years of operation.
However, just ensure the genny has a stout enough stand to keep it in place.

 

[WVBartMan]

I have a 30kW PTO Generator but I'm looking at a 35 kW Generac liquid cooled natural gas powered generator with an auto-switch. On June 29 we got hit by a big storm and then we had 9-days of no electric, my tractor went thru my 100-gallons of fuel and thankfully I had a friend who had access to diesel to refill my 100-gallon tank. The tractor split duties of cleaning up my property with over 24 trees (virgin timber - huge) and keeping the 100+ degree outside temperatures at bay by powering the PTO Generator running my whole house electrical needs (Two - 5 ton AC Units, 3 Frig's and of course the wife's hair dryer).

The price of NG is half of that in Diesel in WV so the cost to operate for extended periods is cheaper as well not to mention the Tractor's R & M cost from extended run times in that kind of heat. Another issue to consider is when I'm not home my wife can have electric immediatly should a power outage occur which has averaged 4-times per year for the last 14-years.

 

[dex3361]

I have a 30kW PTO Generator but I'm looking at a 35 kW Generac liquid cooled natural gas powered generator with an auto-switch. On June 29 we got hit by a big storm and then we had 9-days of no electric, my tractor went thru my 100-gallons of fuel and thankfully I had a friend who had access to diesel to refill my 100-gallon tank. The tractor split duties of cleaning up my property with over 24 trees (virgin timber - huge) and keeping the 100+ degree outside temperatures at bay by powering the PTO Generator running my whole house electrical needs (Two - 5 ton AC Units, 3 Frig's and of course the wife's hair dryer).

The price of NG is half of that in Diesel in WV so the cost to operate for extended periods is cheaper as well not to mention the Tractor's R & M cost from extended run times in that kind of heat. Another issue to consider is when I'm not home my wife can have electric immediatly should a power outage occur which has averaged 4-times per year for the last 14-years.

Mine was out for 9 days. It was a mad house to find gas but diesel was a lot easier to find. Did you lose power when Sandy blew through?