PTO Generators, been here before?

[ishiboo]

Well, measuring the RPM won't help you any, you need to measure the electrical output of the generator NOT what the RPM of the tractor PTO is...

SR

The alternator's frequency is directly coupled to its speed, and there is no way for it to "drift" or anything. So if you know (accurately) that the input is 540RPM, the output will be 60hz. Voltage is another matter since its regulated.

 

[newbury]

Does anyone have an inexpensive easy to use tool to measure PTO speed?
I'm thinking like a little IR gun you point at a marker you put on the shaft and it tells you rpm.

Your tach has the pto speed marked on it, and the pto gen set has a meter, for fine tuning that speed, to get the proper voltage...

SR

My tach has a big range marked PTO speed.

Well, measuring the RPM won't help you any, you need to measure the electrical output of the generator NOT what the RPM of the tractor PTO is...

SR

Where did I write I wanted to use it for a generator? I just want to know what my PTO speed is.

 

[SPYDERLK]

I used a PTO set for years. Worked well, but I am glad those days are over.

Unless I am wrong, no tractor has a shut down system for temp or oil failure. Something to think about before leaving a tractor running wide open unattended.

Why is the tractor wide open?

If operated at part throttle the lower than 60Hz from the generator will wreck some electrical and electronic equipment.

OH. ... You mean at PTO rated rpm. Withoiut a load thats not wide open -- just high idle. Only under a full load is the tractor wide open.

 

[Industrial Toys]

My JD 770 ran wide open to provide 540 PTO RPM. You pulled back the throttle as far as it would go and that was it.

Again I say, 60 cycle is not that critical, voltage is more critical, especially for motor starting.

I've mentioned it before. I tried putting a 2:1 PTO gearbox (Off of a small JD crawler I believe) between the JD 770 and the Onan 15KW genset. The tractor would not even drive it, at no load at all. I guess the Governor was not set up to run at that speed. Shame.

I had a friend that drove a 20 KW (maybe Winco) PTO set with a Ford 5610. For some reason his lights always flickered in a most annoying way. Always! I thought, maybe it was because his driveline was not straight, but he disputed this. I never did figure out what that was all about.

 

[Sawyer Rob]

The alternator's frequency is directly coupled to its speed, and there is no way for it to "drift" or anything. So if you know (accurately) that the input is 540RPM, the output will be 60hz. Voltage is another matter since its regulated.

Some gensets regulate the voltage by rpm...

Just because a pto genset mfg "says" it's a 540rpm genset, doesn't mean that's "exactly" at 540. My voltage is dead nuts on at "slightly" under 540 on the pto... IF I run it at rated 540, the genset rpm is a bit high...

SR

 

[Sawyer Rob]

My tach has a big range marked PTO speed.
Where did I write I wanted to use it for a generator? I just want to know what my PTO speed is.

GEEE, do you suppose, that since you asked YOUR question on a pto generator thread, anyone would "think" that's what you had in mind???

You didn't say you had a tractor either, but I assume that you do!

SR

 

[Industrial Toys]

Best, just make one of these, like I did. No more guess work.

Every Alternators frequency is determined by the speed of the rotor. Newer Inverter style gensets usually produce AC, then make DC, and make 60 HZ AC electronically. Thus, the motor can run at various speeds depending on load.

Actually, all these are "Generators" by broad definition only and are actually Alternators. They produce AC.

The voltage value produced is governed by the field voltage, which is controlled by your voltage regulator.

Some inverter style sets (like an Onan Silent 15KW I had), actually use permanent magnets (I got it, because a magnet let go) that produce 3 phase power. No Field Winding. Then turn it into DC and again make AC with an inverter.

 

[4570Man]

GEEE, do you suppose, that since you asked YOUR question on a pto generator thread, anyone would "think" that's what you had in mind??? You didn't say you had a tractor either, but I assume that you do! SR

Some trucks have a PTO. You never know what some folks have in mind.

 

[Sawyer Rob]

Some trucks have a PTO. You never know what some folks have in mind.

So does my lawn mower, but I don't ask about it on a generator thread... lol

SR

 

[Industrial Toys]

FIRE trucks actually run Gensets off of their PTOs. Some are even hydraulically run.