"The Floating Bear" wrote in message
. uk...
In article . com,
() wrote:

If you can hear a rev drop in your engine from the alternator, you are
already charging at close to its maximum output

But the revs come up again after a while as the charge current drops off.

Being able to hear the revs drop off is no indication of anything other
than the alternator is under enough load to cause the drop. My alternator
can cause an audible drop in RPM when running at only 50-60A. It has
a capacity of 160A. Depends upon the size of the engine, its condition,and
the size of the alternator.

I think the real issue
is that you are only charging 10 minutes at a time

I actually tend to motor for longer than I need to, so that I can get some
charge into the batteries. I'd like to have to motor less, by making the
charging more efficient within the capacity of the 35A alternator, i.e. to
be running at 20A for 30 mins rather than dropping back to 5A within a few
minutes as the standard regulator does (figures guessed at to illustrate a
point).

Sounds like a better regulator is the solution. If the regulator drops back
to
such a low current so soon when the battery still needs charge then
something is
wrong. A proper regulator will keep the charge as high as is safe for as
long
as the battery needs it.

I'd recommend getting a solar panel

A completely reasonable suggestion but several hundred quid to buy for
anything worthwhile, but in the UK I'd be inclined to go for a wind
generator. Still several hundred quid, though. Except that in The 12 volt
Doctor they discuss modifying an old ceiling fan motor to as a wind
generator. I can envisage a way of doing something like the Dolphin
vertical axis unit

I have a couple of permanent magnet tape drive motors that are popular
for making wind generators. Drop me a personal email if you are interested
in one.

Doug

http://www.solarenergyalliance.com/w...or_dolphin.htm

New ceiling fans are under £20 in the DIY sheds now . . .



Regards,
Jerry

Sounds like a better regulator is the solution

My regulator is an ordinary machine-sensed automotive one in the
alternator, which is why I was asking about proper regs with which to
replace it.

A kind offer of the tape drive motors, but I am in the UK. However, I have
a faulty Quantum DLT drive under my desk - is that the kind that the
motors come from or are we talking about one of the big, vertical
open-reel ones that so impressed us in old films?

Regards,
Jerry

"The Floating Bear" wrote in message
. uk...
Sounds like a better regulator is the solution

My regulator is an ordinary machine-sensed automotive one in the
alternator, which is why I was asking about proper regs with which to
replace it.

You first have to verify that you can modify your alternator to work with
an external charge controller.

A kind offer of the tape drive motors, but I am in the UK. However, I have
a faulty Quantum DLT drive under my desk - is that the kind that the
motors come from or are we talking about one of the big, vertical
open-reel ones that so impressed us in old films?

I don't know what type of tape drive the motor came out of. It is about
5" long and 4" in diameter. Weighs a few pounds.

Regards,
Jerry

In article ,
dougdotson@NOSPAMcablespeedNOSPAMcom (Doug Dotson) wrote:

You first have to verify that you can modify your alternator to work
with
an external charge controller.

I don't think that will be a problem. It's normally just a case of
soldering a wire to one of the rotor brush connections. Or am I missing
something?

Regards,
Jerry

"The Floating Bear" wrote in message
. uk...
In article ,
dougdotson@NOSPAMcablespeedNOSPAMcom (Doug Dotson) wrote:

You first have to verify that you can modify your alternator to work
with
an external charge controller.

I don't think that will be a problem. It's normally just a case of
soldering a wire to one of the rotor brush connections. Or am I missing
something?

Regards,
Jerry

It's usually a matter of the physical constraints. Can you get to the
appropriate wires
to make the connections and provide a reasonable exit for the wires? If so,
then
you are set.

Doug