If you are, I just found the deal of the century on eBay. Check out
http://cgi.ebay.com/ebaymotors/ws/eB...m=24 25955223

A 125 amp Electrodyne alternator current bid is $23.50 with no reserve.
It is an $1,800 brushless alternator. Probably one of the best ever
made. I am already committed to 12V or I would be watching it like a
hawk ready to bid.


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Dazed and Confuzed wrote:

can you modify the windings to make it 12 v? Sometimes you can......?


Unfortunately no. Windings on a brushless alternator are evidently
different from a normal comutator type. That was the first thing I
checked when I saw it.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Glenn Ashmore wrote:

Dazed and Confuzed wrote:

can you modify the windings to make it 12 v? Sometimes you can......?


Unfortunately no. Windings on a brushless alternator are evidently
different from a normal comutator type. That was the first thing I
checked when I saw it.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

sometimes you can rewire the field windings to do that....at least you can
in large power generators. (which are really alternators). Instead of 2
windings in series, you put them in parallel for a lower voltage. But if
you can't in this case, too bad. sometimes 24 and 12 v are the same windings
just hooked up differently. Sometimes not....


--
I'd rather put more life in my days than put more days in my life......

On Wed, 30 Jul 2003 18:44:32 -0500, Dazed and Confuzed
wrote:

Glenn Ashore wrote:

If you are, I just found the deal of the century on eBay. Check out
http://cgi.ebay.com/ebaymotors/ws/eB...m=24 25955223

A 125 amp Electrodyne alternator current bid is $23.50 with no reserve.
It is an $1,800 brushless alternator. Probably one of the best ever
made. I am already committed to 12V or I would be watching it like a
hawk ready to bid.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

can you modify the windings to make it 12 v? Sometimes you can......?


Just Tap off from 2 - 12 volt batteries easiest.
Then you split your load between both. - plus you still have 24 volts
as well.
But you still don't gain - as in energy input must still equal work
output - So amps * volts = watts so you still need the motor hp's to
turn it over. So if you don't need it, its overkill.

just_passing@ burntmail.com wrote:

Just Tap off from 2 - 12 volt batteries easiest.
Then you split your load between both. - plus you still have 24 volts
as well.
But you still don't gain - as in energy input must still equal work
output - So amps * volts = watts so you still need the motor hp's to
turn it over. So if you don't need it, its overkill.

There are DC/DC converters to draw 12V from a 24V battery bank but
tapping off of half of a battery bank is not a particularly good idea.
You end up with unequal discharge unless you pay a lot of attention to
juggling loads. Routine recharging of unequally discharged batteries as
one bank will shorten their service life.

What you gain with a brushless is efficiency, lower charging RPM and
reliability. In general, you will burn less fuel to generate a given
amount of amp hours with a brushless than with a regular type
alternator. Their power curves are steeper and start leveling out at
lower RPM. With no brushes, springs etc, the only things that can wear
out are the bearings and Niehoff and Electrodyne oversize those to the
point of excess. They are also electricly quieter. With no brushes
there is no spark and therefore less noise for your radios to contend
with.

The only down side is that they cost to much. Well maybe not compared
to what balmar charges. West marine wants $1,800 for a Balmar 96-275.
You can get the equivelent output from an Electrodyne GEB200 for about
$1,200. You might wonder about a 275 amp alternator being equal to a
200 amp one but the Balmar is COLD rated 275 amps at 6,000 RPM and the
Electrodyne is HOT rated 200 amps at 2,700.)

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Glenn:

Your 'Rutu' web site does not specifically say why you chose to
install a 12 V system (as opposed to 24 Volts). Given that most of
what you're doing is fairly 'cutting edge', I might have thought you'd
opt to keep the wire size (and the subsequent weight) "small."

What was the deciding factor(s)?

Mike Worrall

I don't know how this particular alternator is voltage controlled but usually
just change the voltage regulator to 12V. When the field current is reduced
the output voltage is reduced in most cases.

I have changer the internal regulator in a standard 12v. GM alternator and it
operated for a year . ( The unit was sold ).

Mike
******************

If you are, I just found the deal of the century on eBay. Check out

http://cgi.ebay.com/ebaymotors/ws/eB...=1&category=33
573&item=2425955223

A 125 amp Electrodyne alternator current bid is $23.50 with no reserve.
It is an $1,800 brushless alternator. Probably one of the best ever
made. I am already committed to 12V or I would be watching it like a
hawk ready to bid.


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

mike worrall wrote:
Glenn:

Your 'Rutu' web site does not specifically say why you chose to
install a 12 V system (as opposed to 24 Volts). Given that most of
what you're doing is fairly 'cutting edge', I might have thought you'd
opt to keep the wire size (and the subsequent weight) "small."

What was the deciding factor(s)?

Availability which reduced itself to the all mighty $$$$$$$. :-)

There are many times I wish I had gone 24V. It would have made things a
lot more efficient but you just can't find enough high quality stuff in
24V using the scrounge/surplus/auction methods I am so fond of. :-)
With patience you can find a lot of bargains in 12V but not in 24V.

I still would have wired for 12V. I have an account with a couple of
distributors. You would not believe the mark up on marine wire.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Glenn Ashmore" writes:

Availability which reduced itself to the all mighty $$$$$$$. :-)

There are many times I wish I had gone 24V.
snip

Another consideration, filament lamps.

The lower the voltage, the larger the filament,

The larger the filament, the less likely it will be affection by vibration.

6 VDC is better for filament lamps on a boat, but you live with 12 VDC.

Way back when, each pilot light used in machine control panels contained
it's own small transformer.

115VAC input, but the lamp itself was 6 VAC.

A Pilot light that doesn't work is a real PITA.

As far as 12 v 24 is concerned, if 24 VDC is good, 48 VDC is better. If
48VDC is good, etc, etc.

Higher distribution voltages best serve large loads like a windlass or a bow
thruster; however, high mechanical power DC motors are a real headache.

Basic reason I'm installing an engine driven hydraulic system to handle the
bow thruster and windlass.

HTH


--
Lew

S/A: Challenge, The Bullet Proof Boat, (Under Construction in the Southland)
Visit: http://home.earthlink.net/~lewhodgett for Pictures

Actually it is not that dificult to run both 12 and 24 volt systems. We use
24 volt for high load items and drive it with a seperate alternator and
charger/inverter. It is used to run fridge, inverter, winches, bt, and then
is also stepped down with a converter to supplement the 12 volt side. All
you need are two busses and breakers as need for the application.

Good luck

B

"Glenn Ashmore" wrote in message
...
If you are, I just found the deal of the century on eBay. Check out

http://cgi.ebay.com/ebaymotors/ws/eB...category=33573
&item=2425955223

A 125 amp Electrodyne alternator current bid is $23.50 with no reserve.
It is an $1,800 brushless alternator. Probably one of the best ever
made. I am already committed to 12V or I would be watching it like a
hawk ready to bid.


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com