On Mon, 27 Apr 2009 20:29:29 -0700 (PDT), "Capt.Bill"
wrote:

On Apr 26, 7:33*pm, Bruce in Bangkok
wrote:
On Sun, 26 Apr 2009 17:03:15 -0500, wrote:
On Wed, 8 Apr 2009 00:35:14 -0700 (PDT), "Capt.Bill" wrote:
It's driving me nuts, because I remember seeing and reading about this
thing in the past. But for the life of me I can't think of the name of
it. It ran off the main engine to give you 120v power while you were
underway. It may have been a high output DC alternator coupled with an
inverter to give you sable power at varying RPMs. Or you may have had
to run at a consistant RPM. I just can't recall the details.

I think that you are talking about a modification to a conventional
auto alternator that provided 110 VAC. I remember them also.

As far as I remember they just bypassed the normal diodes in the
alternator and you controlled the engine RPM to get 60 H. I also don't
remember that they were very popular.

What is it that you are trying to do?

Cheers,

Bruce in Bangkok
(bruceinbangkokatgmaildotcom)

I was trying to help someone with a power boat who was looking for a
way to generate 120v power while underway without having to by a stand
alone generator.


Would it be easier to install an inverter? Since it is to be used
while the engines are running there shouldn't be a heavy load on the
batteries.

One problem that might arise using a propulsion engine driven
alternator is that engine RPM would govern the frequency and you
probably don't want to be much more then 10% above or below the
standard frequency, depending on what you are powering with the AC.

Frequency(cycles per second) = (number of poles/two) x (speed of
rotor(revolutions per second))


Cheers,

Bruce in Bangkok
(bruceinbangkokatgmaildotcom)