I'm looking for a high output DC Generator
. I've noticed there are only a few off-the-shelf solutions. The Ample power
Genie 150A unit being one of them. This seems really quite expensive though. For what is basically a diesel engine
with a large alternator
I would rather build my own.
I'm thinking of buying
a Yanmar 1GM10
bobtail (no gearbox) and mounting a balmar
90 series 150A dual 1/2" belt alternator
to where the exisiting yanmar
35A alternator is.
I've looked at the graphs and I reckon I need to run the engine
at around 2000rpm which will give 5hp.
I think a ratio of 2.5 (2.7" / 7") for the pulleys will be optimum.
For 2000rpm I'll get 5030rpm at the alternator. According to the balmar
output graph it can supply up to 145A at that rpm
Using the rule
of thumb of 1hp for every 25A, I could get 125A max at this rpm
. I have 4 T105 6V batts giving a total of 450AH capacity. With a Sterling PDAR regulating the alternator I shouldn't expect the batts to need more than 100A. If it does, I can always turn up the rpm of the engine.
I can see only a few small issues to overcome with this system.
1. Actually getting a large case alternator to mount to the existing mounting position of the 1GM10
. Am I right in saying the yanmar has a dual foot 3.15" ID Mount? If so, would the Balmar 90 series 150A model fit OK?
2. Attaching a second pulley on to the crank (for the second belt).
Should I be able to bolt this to the existing yanmar pulley on the crank?
Does anyone know the diameter of the 1GM10 pulley? The tech docs don't specify this.
3. There is the side load issue for the engine bearings. Has anyone had any realworld problems with this? I could design a support bearing to take the load, but this seems overkill at the moment.
The other option is to direct drive it from the back of the engine, but I've not found any alternators which will give enough amps at such a low rpm. For noise/fuel economy purposes I'd rather run the engine at as low an rpm as I can get away with.
I'm also thinking of fitting a water
separator on the exhaust
so there is no annoying splashing noise
I've searched extensively on the web but have only found one example of this being done with a 1GM10 - That was Ellen McArthurs round-the-world boat!
I have considered using a Kubota Z482 based engine such as the nanni or beta. But they are much more expensive than the yanmar (My yanmar dealer has offered me a good price
on a 1GM10). However with the 2cyl vs. the 1cyl, it probably would be a little smoother going for the kubota.
Was wondering if anyone has thoughts/ideas/experience with something similar?