Yanmar 10hp L100 Diesel video of 28v 450 amp DC generator.

[90cummins]

I built a DC generator to power my 4kw home inverter when the power is out.
I bought and rebuilt a 10hp Yanmar L100 diesel that I bought off Craigslist and use it to power a 28v 450 amp Niehoff N1603-2 DC generator to support my 24v off grid inverter.
I have the engine turning at 2750 which is the sweet spot for minimum fuel consumption & peak torque and the alternator is turning at 1450 rpm. Run time with a 1kw AC load is 6hrs per gallon.
The frame is made of 1/4 steel and I used bolts rather than welds so I can easily modify it.
I could use some help in a couple areas.
One is making or selecting a device to adjust the engine speed as the load increases.
Another area I need help with is a way to adjust the output voltage from 28.6v to 27.5v.
I have the manual and engineering drawings if that is of any help.
At 28.6v the generator is constantly pushing a charge into the batteries even when they are charged.
When a high load is turned on the generator attempts to carry the load because the battery float voltage is lower than the charge voltage.
Reducing the charge voltage will allow the batteries to share the load rather than allow the generator to carry it.
I'm thinking that I could adjust engine speed using current as a reference, but I have no idea how to do this.
The generator also has an AC output for use as a speed reference if that is of any help.
I have a video on YouTube I think you will enjoy.
Thanks 90cummins

Yanmar 1hp Diesel DC backup Generator - YouTube

 

[hr3]

Nice looking setup.. As for the governor, I had the same problem with a 6.5 kw Honda liquid cooled that I picked up for free. The governor was shot and to get at it meant separating the whole unit . I wanted simple and reliable so I ordered from generac a electronic governor for an 2.2 Isuzu generator motor. It came with stepper motor all the brackets and linkages and a 120v controller. It worked great and has adjustments for hz.& speed pickup .

 

[90cummins]

Could you get a part # and take a photo so I can check it out?
I actually have two generators that I would like to add an electronic gov on.
My other unit is a Military MEP-952b APU that produces 28v DC also.
It has a 15hp Farymann 43F diesel that would definitely benefit from addition of an electronic gov.
Thanks
90cummins

 

[wmonroe]

Neat setup. Are those small air cooled diesels common? I've never seen one (never looked either so maybe that's why) but like the idea.

 

[90cummins]

Common in industrial equipment and becoming more common in portable high end consumer generators.
But as you said you never looked either.
They are ideal for generators both portable and as backup because the fuel does not go bad like gasoline.
They can sit for months (year or more) and will fire up on the first crank.
That's one of the reasons I used a diesel plus if you heat your home with oil you have fuel for the generator.
90cummins

 

[wmonroe]

These are very interesting, I almost always have diesel around but don't always have gasoline. Might start looking for a generator with one of these engines.