PTO Generator Question

[RickB]

I'd be more concerned with your test equipment than the generator.

 

[derek01]

Just curious I have been thinking about buying a generator like what you bought how much did it set you back I have a 5500 watt generator but with the well pump it is just a little too small.

 

[TRR]

If you're running within 24 seconds per hour, I wouldn't worry about it. Most specs I see for frequency say 60 +/- 5% which would give you +/- 180 seconds per hour. I think your meter is off. And also, because frequency on generators are dependent on RPM so if your rpm is steady, so is your frequency. The only thing I'd worry about being damaged by frequency are some of the AC motors that are frequency dependent.

It's been a long time since I worked in an electronics lab, but I suspect that the reason you're getting strange readings is because your equipment/test gear are not grounded properly. Whereas the power grid is grounded.

 

[Harvest Moon]

Just curious I have been thinking about buying a generator like what you bought how much did it set you back I have a 5500 watt generator but with the well pump it is just a little too small.

Felt lucky to get it for $700, although I've seen listings where they've gone for $400 at farm auctions. I've also seen them listed for sale at $1400.

 

[Harvest Moon]

It's been a long time since I worked in an electronics lab, but I suspect that the reason you're getting strange readings is because your equipment/test gear are not grounded properly. Whereas the power grid is grounded.

Never did develop a complete understanding of portable generators and grounding. Seems like if they aren't tied into an earth grounded system, they are not required to be grounded to earth.

Wonder what happens if you grab a live wire and you're standing in a puddle with a non-earth grounded system? And I'm still getting used to the idea that the tractor shares it's 12 volt DC ground with the generators 240 volt AC ground.

Anyway, it makes sense that grounding could be a factor.

 

[crazyal]

My guess is your generator is noisy and your meter is getting confused or maybe it's picking up on a harmonic frequency.

 

[BethesdaEC]

Never did develop a complete understanding of portable generators and grounding. Seems like if they aren't tied into an earth grounded system, they are not required to be grounded to earth.

Wonder what happens if you grab a live wire and you're standing in a puddle with a non-earth grounded system? And I'm still getting used to the idea that the tractor shares it's 12 volt DC ground with the generators 240 volt AC ground.

Anyway, it makes sense that grounding could be a factor.

If you plug it into a transfer switch, the ground will pass through to the tractor from your main panel.

 

[Ken]

Remember you have a PTO lighting system that is 50 years old. the name plate tells you the rpm and frequency and voltage.
Your electronic measurment is designed for higher frequencys. so you are measuring apples and oranges.
The farm generator doesnt have the noise suppressors of todays equip.
Removing the covers on rear and clean out mud dubers nests and mouse nests make sure the brushes slip freely on holders and springs hold the brushes have tension. these is a cleaning stone to polish the brush slip rings. get one at a electrical shop.
This will reduce the arcing of brushes and will clean up the frequency reading. Still old meter type reading of 115/120 volts is best to determine power.
Can't wear them out but seems people who have them never take the needed care to keep proper operation when needed.
You got a good buy at $700.00
ken

 

[90cummins]

I have several portable generators including a Generac PTO 25, 25kw/50kw surge unit.
I'm no generator expert but from my experience a generator with brushes tends produces power that is noisy or dirty when there is no load which creates problems getting a good HZ reading.
To resolve that I connect a resistance load such as a hot plate to clean up the power so my Fluke can get a nice stable reading.
I believe the hot plate eliminates the stray current like a capacitor? Perhaps someone here can elaborate on that.

Tim

 

[psj12]

It seems difficult to find a meter for reading electric line frequency that is affordable.

 

[zzvyb6]

The Kill-A-Watt units are on eBay for under $21 (free shipping). That's affordable.

How straight is your driveline? If it has some angulation in it, there will be some cyclic variation in the rpms.

I have the exact same PTO alternator and mine works just fine. Measured Hz. is set to 60, volts is about 125. I prefer to target Hz. instead of voltage. My pto tach reading is high at the specified Hz.

 

[JB4310]

It seems difficult to find a meter for reading electric line frequency that is affordable.

Tell me about it.

A guy from the power company left a beautiful fluke brand meter, with the fluke clamp and the leads at my house when they were looking for a problem I was having. This one had a back lit display and several other high end features that are only found on professional models.

I was gonna keep it, but my conscious got the best of me and I gave it back when they came back the next day. they didn't even ask about it and acted like they could care less that they left it in the first place.

I've second guessed my decision to return it, even though most would say it was the right thing to do.

JB

 

[CompactTractorFan]

I've second guessed my decision to return it, even though most would say it was the right thing to do.

It was the right thing to do...:thumbsup: