Shaft Conversion for PTO Generator

[Mickey_Fx]

This thread is a good example of what happens when an inadequate description is given. We all have something a little different in our mind and comments and suggestions wonder all over the place. I'm sure most of us had in mind a more modern setup with a gearbox transmission and wasn't sure about the sq shaft.

Have to agree with LeeJohn about half the pto shaft is missing. As for speed change, the belt drive has to increase the input speed by 6.666 to give an output speed of 3600 rpm when input speed is 540.

 

[dex3361]

I saw square shafting at Tractor Supply for the other half of that PTO shaft.

 

[DieselDon]

I agree with the 'inadequate description' and I own it

So far, you've all helped me figure this out. I studied it more and am hopeful that the ratio (from the belt drive) will indeed allow it to work with a 540. And I'll get the second half of the shaft or swap it out at the universal joint. For only $150, I consider it a good learning opportunity. Especially with the help of this forum.

Thanks much,

 

[DieselDon]

Thanks also for the mention of Tractor Supply. I'll hit it up tomorrow

 

[DieselDon]

Ok,

I found the shaft at TSC and got the PTO generator running. It generates but at very low output. You'll note in the picture below that the pulley ratio (top n bottom) look like their set up for a 540rpm correct?
I plugged a droplight in and got a variable brightness out of it depending on the rpm's on the tractor. The voltmeter never got above 100 even though it looks like the sweet spot is around 250. And I could only get it to 100 by running the tractor at 2750 rpms.

Question, I thought I had it grounded well enough, but would a poor ground affect the lower output? Or, perhaps the beast is just too old to generate much.

 

[bcp]

Measure the two pulley diameters. The difference doesn't look like enough to me. Maybe it was set up for a faster PTO.

Put your numbers into this calculator:
http://gadi.agric.za/software/renting/pulley_calc.php

the belt drive has to increase the input speed by 6.666 to give an output speed of 3600 rpm when input speed is 540.

Bruce

 

[RFB]

666?

You are going to have a devil of a time to makeit work.

 

[RFB]

666?

That generator will be a real beast.

 

[aczlan]

Do you have a multimeter that will measure hertz? If not, most Kill-A-Watt meters will measure both voltage and hertz for not too much.
You need to check how many hertz it is putting out and adjust your RPMS until it is putting out 60-62 hertz unloaded (or with just a little load like your drop light plugged into it). Then see how many volts it is putting out.
I would not run it much more until you can check the hertz and voltage output. You could burn up the voltage regulator if you aren't spinning it fast enough.

Aaron Z

 

[DieselDon]

The pulleys measure as follows:

Large = 7" (roughly 175mm)
Small = 2.5" (roughly 60mm)

That's the issue right? If the PTO generator calls for 3600rpm's and the tractor is a rear 540, I need a larger ratio between the two pulleys. It seems to make sense why the volts are only reading 100 or so.

Any brilliant ideas? Like, sell it and buy a different one? I only have $150 into it and it's a Winco. Old but apparently working.

Thanks for all the quick responses