DC Alternator

Morning guy and gal's. I'm in the market for a dc alternator for charging my battery banks. I currently am using a 13th propane air cooled gen. I just picked up a 2 cry yanmar liquid cooled diesel and would like to run a dc gen/alt and most controler. I've looked around some and most units are smaller for windmill applications.

 

One of the hot setups for two to three KW generators (Honda and Yamaha) is an alternator powering a car size battery with an AC inverter running off the battery. This way there is no need to match frequency and many gen-sets can slave to each other.

Even so you could roll your own using a semi-truck 220 Amp alternator. Even this Amperage only puts out about 2.6+ KW which is around a 4 HP load. What's the HP of the Yanmar and what's it's most efficient load and rpm range. I think you should shoot for efficiency with the ability to surge a little when needed.

I'm thinking off the shelf low cost components that will last a long time and can be replaced easily. Cost vs performance. There are also some interesting offerings on eBay in the 5KW range.

 

Yes I agree with @ghrit . Your post has too much missing info/unclear terms to advise in detail where to go with this. What is a "most controller"?

Anyway, that Yanmar is one of the best, if not the best small generator on the market. I would get a nice battery charger sized for your application, push it with the Yanmar, and be done. You cannot build anything better than a Yanmar.

I use a small 1400 watt Honda generator with a 40 amp automotive charger to keep my batteries topped off when my solar panels can't keep up. Even in the dark of winter I don't need to run the generator more than an hour or so per day.

If you want something dedicated to battery charging only, the suggestion of truck alternator & small engine combo is excellent. It's a fairly easy do it yourself project that does not cost a lot of money. There are tons of YouTube vids that will show you how.

 

Also , your driving it with belt & pulleys or direct . My Yanmar 2 Cyl is 1800 rpm with HI set at 2100 rpm .
Your solar ? Like me at 1/2 way so far. Spent the day (Weekend doing this , & every weekend till 2016, then I'll be finished) Need to know your battery voltage & amp hr's , Cuz C20 is what you want to hit.

Sloth

 

Sorry for the lack of info in my first post. My system is 16 6 volt deka batteries in 2 48 volt banks. I have a outback 60 charge on 9 250watt sharp panels and 8 100 watt panels on a xantrex charge controller. I have dual xantrex inverters that are used currently when the ac propane generator is charging the batteries. I would like to use a dc system with another mppt charge controller. The diesel unit will be more efficient and since it's liquid cooled i can use the radiator to temper my garage in the winter.

Thanks
Jason

 

I'm not near the motor now but know it was off a semi. It was used for a/c, heat and power while parked. It has a plate that says 8.8kw at 2800 rpm. I would like to back it off to 1800 rpm. Not sure how to answer the question about peak loads.

 

That is kinda how it's set up now. I was hoping to just be able to find a 48 dc unit. The only ones I came up with are these 2. PM-ALT.com Permanant Magnet Alternator for Wind Turbine the second is only good to 1200 possible 1600 max. Not sure about the first one.

Jason

 

I had a couple of wind generators over the years on my sailboat. The best one was made from a 2.5kW industrial sewing machine motor PMDC. Now, that motor was a nominal 100V motor, but connected to a battery bank it was held to the bank voltage and put out a decent current. I think you do not have to concern yourself too much with the nominal voltage of a PMDC motor/generator. But you do need a diode between it and the batteries. I did not buy the motor direct from the distributor - a wind generator company had it drop-shipped to me, so can't help you with source, but it was less than $50 for the motor (shipping cost more).