Perkins P3

I think there is too much of a mismatch between the alternator and the engine to get anything worthwhile out of it.To run that alternator on full output will need at least 120hp.Granted you say you don`t want the full output but I still don`t think it will be workable and unless you have reasonable voltage control anything you do get out it won`t be much use to you.In fact I think it will take all the P3`s power to spin the alternator up to speed.But,you will get plenty heat from it. Mark.

Thanks Mark. I did have a few misgivings about the size of the alternator. I have got a selection of alternative engines, however, noise is likely to be the biggest issue.

I have a Cadillac V8 diesel, 1979 which might do the job. It depends on how the injector pump can cope with biodiesel. Or maybe a Ford Mondeo, diesel, that I shall be scrapping soon. It is fairly quiet already and at 1500 rpm., in a purpose built room it may be the best bet. I am still puzzled by what to do about the voltage regulator, is it something I might be able to make or maybe modify something else? I am assuming that it depends on feeding a varying exitation current back into the exitation winding according to the load on the alternator.

Regards George.

Thanks Mark. I did have a few misgivings about the size of the alternator. I have got a selection of alternative engines, however, noise is likely to be the biggest issue.

I have a Cadillac V8 diesel, 1979 which might do the job. It depends on how the injector pump can cope with biodiesel. Or maybe a Ford Mondeo, diesel, that I shall be scrapping soon. It is fairly quiet already and at 1500 rpm., in a purpose built room it may be the best bet. I am still puzzled by what to do about the voltage regulator, is it something I might be able to make or maybe modify something else? I am assuming that it depends on feeding a varying exitation current back into the exitation winding according to the load on the alternator.

Your caddy V8 might be the best beast to run at 1500rpm given it will be a torquey thing at those revs, whereas the Mondy TD will be pretty flat as

1500 is too slow for the turbo to spool under load. You would need to arrange some V belts or gearing so the 1.8 is spinning at 2500rpm or thereabouts off load.

Possibly some modern AVR unit could be employed or modded to provide excitation for your generator, I think you should speak with the technical dept at Newage, Stamford Primac or Leroy Somer or someone like that..

Tim. .

Are car diesel engines governed throughout their range? I would be more concerned about maintaining a constant engine speed than controling the alternator output.

John