Soundguy et al PTO Gen ???

[ovrszd]

Sandman,

The capability of Hp v. PTO output is understood (Roughly 2 hp per kw).

What I am trying to determine is the meaning of "Rated Speed" given as 2700 rpm for my 5030. I interpret(and possibly erroneously) that as meaning the rpm that develops maximum rated hp. Is that number (2700) what it will take to achieve 540 pto rpm under load?

The tachometer on your tractor should be marked for 540 PTO speed. I doubt it's 2700 but a quick look at the tach will tell you where the rpms should be to achieve that PTO speed.

 

[JoeL4330]

You seem to have a "Grand L", which has an "intellipanel" ...so, to find out the engine RPM setting to achieve 540 at the PTO, idle the tractor, push in the clutch, and engage the PTO (having checked that nothing will contact the splined shaft ...remove the rubber cover, first, if you have one) ...then, with the PTO engaged, push the dashboard button until the LCD display on the panel is showing PTO RPM's ...then increase the engine RPM until you have 540 indicated on the LCD ...now, look at the Tach and note the engine RPM ...it will likely be 2450-2500 ...memorize it.

Generally, that engine RPM setting will be below the peak horsepower setting, but actually just beyond the max torque setting ...the reason for setting it on the "backside" of the torque curve is so that if there is a load that suddenly starts to bog down the engine, the torque will actually rise momentarily and may see you through a small transient overload and not stall.

My guess is that this is the answer you would get if you posted in the Kubota user forum

 

[Partsman2]

I had an old Ford 2000 that made 540 PTO RPM at 1800. When I bought my new JD 4710 I noticed that it took 2600 engine RPM to make 540 PTO RPM. It seems like the thing is screaming but that is where you have to run it to get 540 at the PTO.
The tractor actually loves it. The power and torque at that engine speed are awesome. The engines are designed to run at those speeds continuously so don't worry about how it sounds.
Like you I only run mine between 1800 and 2000 when doing non-PTO work except in hot weather where I'll keep the engine speed a little higher to achieve better cooling for the hydraulic system.
Your operators manual should tell you exactly what the engine RPM is to make 540 PTO RPM and it most likely is around 2600 - 2700 range.

 

[jinman]

I know this is not the case with RFB's 5030, but some european tractor models have a PTO that will run 540 at two separate engine speeds. This allows a much lower engine speed for very low torque PTO applications. I wish this option was available in the USA, but there are probably "issues" I don't know about that prevents it.

 

[RFB]

Thank you ALL for the experienced counsel.

I am still on the steep portion of the learning curve, and your advice is a real boost uphill.

RFB

 

[Highbeam]

Jinman, you may be referring to the 1000 rpm PTO option on some machines. My 30HP tractor can spin the PTO at 540 or 1000 depending on which direction I throw the PTO engagement lever. If I only wanted to get 540 PTO RPM while being in the 1000 PTO RPM setting then I would idle down the engine rpms to about half of that required for 1000 pt rpm. If I did not need maximum PTO HP then this would be a great option for conserving fuel and less noise generated though I am certain that the engine is happy humming along at full RPM which for my machine is a healthy 2450 rpm or so.

 

[RFB]

In doing some checking on pto gens, I called Winco gen and spoke to a tech rep.

He said that their 25kw has no surge capability, and that although fine for pump starting and general utility usages, their voltage regulation capability was not a good match for more sensitive applications (residential reefers, etc). He said that the Winco vr was done by means of a "saturated field" process, and if I remember correctly, 6% being the best expected.

The TigerPower I am researching has electronic voltage regulation of ±2%, which to my admittedly novice mind seems better if you are planning for whole house standby power. (The 5 year warranty is attractive as well.) I figure that minus the trailer, I should be able to pick one up for about$2500, which although a little high compared to some, it is not altogether out of the ballpark for a 30k gen.

 

[Partsman2]

Of course.. even if you don't have 60 pto hp.. the genny will still kick out electrical power based on the input hp.. I.e. if you can only supply 50 pto hp.. then you can expect 25kw.. and your genny is a tad overrated.. but that's not a bad thing.. having extra genny capacity means you aren't slamming it to the wall. Soundguy

I have a question. What happens if you are running a 30 KW genset on a tractor with a 50 hp pto output and you put too much demand on the generator? In other words your pto hp can support 25 KW and you hit with a 28 KW demand. Does it stall the tractor?

Obviously you can avoid that by wiring your circuits properly and making sure you can't overload the tractor but it is something to be concerned with. Those engines don't like to go from 2600 rpm to 0 in a split second!

 

[Soundguy]

If you try to use more electrical load than the tractor can handle, I'd expenct the engine to stat lugging down, thus dropping rpm, thus dropping frequence. Some of your loads may be frequency dependent and drop out.. Certaintly you will be dropping volts and cycles.. I wouldn't 'aim' for that situation... In some cases, you may be increasing the current demand due to a needed wattage of an application, and with the voltage falling.. the only way to increase or maintain wattage is through increased 'I' flow. this can burn windings.. etc..

Soundguy

 

[Soundguy]

I know this is not the case with RFB's 5030, but some european tractor models have a PTO that will run 540 at two separate engine speeds. This allows a much lower engine speed for very low torque PTO applications. I wish this option was available in the USA, but there are probably "issues" I don't know about that prevents it.

I thought some of the NH units had the 'epto' or did I misread?

Soundguy