just tested my pto-genny on my ford 8n

[Soundguy]

I finished bolting the genny down to the pallet, and then put the pallet on the carry-all, and adjusted the pallet with the pto shaft hooked up to get everything correct, and then bolted the pallet down to the carry-all.

I had run out of time and needed to get to work.. but I just HAD to see the pto gen run. I fired up the N.. engaged the pto at lo rpm, and then throttled up slowly to pto rpm. The needle on the genny popped up into the green in about a second. I quickly grabbed my freq counter and jabbed it into the outlet.. 60hz on the nose.. and then jabbed my vom in as well.. 121vac.. The only load I had available in the garage to test on quick notice was my power drill, so I plugged it in and let it go.. worked great.. though I know that is hardly a 'test' load.

Anyway.. I was already late, so I shut it all down, and backed the N into the garge and left.

Soundguy

 

[rockinmywaypa]

Ahhh, the sweet taste of success. Glad to hear you made it through the storm.

 

[Cliff_Johns]

Thanks for the update. I suppose some pictures will follow. I'm glad you opened a new topic for this, the other one drifted a bit.

Cliff

 

[htiek126]

I am curious about the PTO genset setup (I would like to get one for myself):

The frequency output is defined by the engine RPM, and therefore is load dependent. I figure that if 2400 engine RPM translates to 60 Hz (cycles per second), then every 40 engine RPM changes the electrical output by 1 Hz.

Does the genset have any electrical protection for the wrong frequency? For instance, when you start up the genset, is it up to you to connect the electrical devices after it reaches a steady state, or is there some "smarts" or an alarm in the genset? Am I correct to assume that there is no feedback to the tractor engine to maintain engine RPM when the load changes? Knowing you will take the time to study the finer details of your system performance, I am curious to hear your assessment of how much user intervention is required to keep the system tolerances reasonable under startup, steady state, and changing load (turning on your refrigerator and well pump at the same time) conditions.

 

[alco141]

what i have found out using my NH 1520 @ 19 pto hp and a 25 kw generac pto generator, the torque on the diesel is much greater than on any kohler or briggs and straton motor so the load does not change the frequency that much. i set mine on about 1% above 60 hz without load, when adding load i have found that it may dip to 59hz on motor start up but goes right back to 60 hz . so once you set the throttle it does not seem to vary much with refrig, freezer, lights, 1 hp well pump cycling on and off.

that said there is no protection for over or under frequency mine is a operator regulated system period. having tried to overload the system with startup by throwing all the breakers at once i will tell you the diesel will put out some black smoke for about 5-10 seconds when a whole house load is applied at once, but them comes right back to 60 hz and does not dip below 59 hz on the start up. so i have been particularly pleased with the machine.

the only draw backs i have seen with this set up is :
1, it ties up your tractor.
2. your wife or kids may not be able to hook up the pto to the tractor. mine is mouned on a trailor making it easy for me to handle as the generator weighs about 350 lbs.
3. you need to fuss for about 30 seconds to get the throttle set initially for the corrrect output.

fwiw,
alex

 

[Soundguy]

</font><font color="blue" class="small">( if 2400 engine RPM translates to 60 Hz (cycles per second), then every 40 engine RPM changes the electrical output by 1 Hz. )</font>

On my antique, that's 1490 engine rpt to keep 540 on the pto.. so yes.. i believe the ratio works out close.. so ever 25 or so rpms change is a 1hz variation.

</font><font color="blue" class="small">( Does the genset have any electrical protection for the wrong frequency )</font>

No.. it only has a volt meter, with a couple red sections, and a green section in the middle, with a black line at the dead on 120v mark. Instructions state to spin the genny up to speed before plugging in a load.

</font><font color="blue" class="small">( Am I correct to assume that there is no feedback to the tractor engine to maintain engine RPM when the load changes? )</font>

The tractors governor is what will be correcting for load changes. Theoretically, if your governor is working good, and you have sufficient throttle , and hp left over, the engine should maintain the rpt.. however a large load may lug it for a second.. just depends on how tolerant the electrical equipment is during a 'brown-out'.

Soundguy

 

[To20Chris]

Soundguy - that brings up a question I've been pondering - on our old gas engines, the "throttle" is really a governor setting - what about diesels? It appears that the speed control on the diesel is just a fuel control, but I can’t tell if it has a governor. I always assumed it did, but…..

Obviously, for generator use, an engine with a governor is best. It’s not quite as good as a governor running from a control system on the generator, but all in all the output frequency is a function of the input shaft speed.

I hope it works well for you!

 

[Soundguy]

Though I know(think)? the diesels i've had have gov's.. They just don't seem to function like an old gas engine gov. On my 8n when you hit a load, the engine picks back up to the original set rpm ( if it can ).. on my diesel.. as the load gets higher.. I have to manually adjust the throttle.. was like that on my last diesel as well...

Soundguy

 

[ZJ_HR]

All diesels have speed regulators, some are pneumatic - vacuum (older ones), majoriti mechanical, and some are hydraulic.
Regulators (governors) on tractor motors are proportional, so bigger speed drop cause more fuel.
Gensets have more precise speed regulators, dedicated to narrow band application (1000, 1500 or 3000rpm, for 50Hz or 1200, 1800 or 3600 for 60Hz).

 

[jinman]

Soundguy, that generator sounds really great. Let me be the first to say that I hope Ivan doesn't give you a chance to use it for real. I know you will find plenty of good uses for it without having to "survive" after a hurricane. That ol' 8N should be a perfect match. It's amazing how quickly the governors respond on those old Fords. /forums/images/graemlins/cool.gif