Alternative Power sources - Source for 48 volt Alternator?

Author

Source for 48 volt Alternator?

Ulysses

2007-06-06, 1:25 pm

Hi.

Being very unhappy with using the built-in chargers in my new Outback
inverters I'm considering using a small engine to run a 48 volt alternator
for charging my battery bank but I can't seem to find any. Are these
standard equipment on some kind of industrial machines such as fork lifts or
tractors or whatever? Anyone have any links? I'm thinking 40-50 amps would
probably be about right.

I'm also considering various chargers that could be ran from a generator.
It turns out that if a 2:1 step-down transformer was used 1/2 of 115 volts
just happens to be almost exactly the right voltage for bulk charging a 48
volt bank. After rectifying this will probably change but I'm thinking it
might be possible to adjust the voltage by simply changing the engine speed
a little. Equalization might also be possible.

I looked at 48 volt battery chargers and Iota with the IQ4 seems to be the
best choice (that's affordable anyway) but their 48 volt charger is only 15
amps unless you get two 24 volt chargers and connect them in series and then
it starts getting pricy again. Building a power supply to feed into the
MX60 charge controller does not seem to be an option but if it could be done
then the 3-stage charging and equalization would all be figured out already.

I turned my first Honda eu2000 into a belt-drive generator head but I can't
seem to find the DC output going to the inverter. I don't know the voltage
that it uses but I figured it was worth a look on the off-chance it might be
in the right range.

Thanks.

Neon John

2007-06-06, 5:25 pm

On Wed, 6 Jun 2007 09:10:05 -0700, "Ulysses" <eatmyspam@spamola.com/> wrote:

>Hi.
>
>Being very unhappy with using the built-in chargers in my new Outback
>inverters I'm considering using a small engine to run a 48 volt alternator
>for charging my battery bank but I can't seem to find any. Are these
>standard equipment on some kind of industrial machines such as fork lifts or
>tractors or whatever? Anyone have any links? I'm thinking 40-50 amps would
>probably be about right.
>
I'm not aware of an off-the-shelf alternator but any car or preferably heavy duty
truck alternator will go to 48 volts with at most, a change in diode pack to a higher
voltage one and the proper regulator. On my current version of my Cordless Battery
Charger (TM)
http://www.neon-john.com/Generator/CBC/CBC_home.htm (these are of an early prototype
but you get the idea), voltage of 12,24,48 or 72 are available at the turn of a
rotary switch.

>I'm also considering various chargers that could be ran from a generator.
>It turns out that if a 2:1 step-down transformer was used 1/2 of 115 volts
>just happens to be almost exactly the right voltage for bulk charging a 48
>volt bank. After rectifying this will probably change but I'm thinking it
>might be possible to adjust the voltage by simply changing the engine speed
>a little. Equalization might also be possible.

If your generator has an externally excited field with slip rings then you'd want to
change the field voltage instead of engine speed. Ripple from rectified 60 hz is
considered harmful for batteries and the lower frequency, higher amplitude ripple
from a slowed generator would be worse.

>
>I looked at 48 volt battery chargers and Iota with the IQ4 seems to be the
>best choice (that's affordable anyway) but their 48 volt charger is only 15
>amps unless you get two 24 volt chargers and connect them in series and then
>it starts getting pricy again. Building a power supply to feed into the
>MX60 charge controller does not seem to be an option but if it could be done
>then the 3-stage charging and equalization would all be figured out already.

You might also take a look at Progressive Dynamics. I know they offer a 48 volt
version of their Intellipower that is quite reasonably priced.

>
>I turned my first Honda eu2000 into a belt-drive generator head but I can't
>seem to find the DC output going to the inverter. I don't know the voltage
>that it uses but I figured it was worth a look on the off-chance it might be
>in the right range.

I didn't quite follow that. Did you remove the engine from the generator head and
belt drive it or use the engine to belt drive another generator.

An EU with bad electronics is still valuable. Toss the inverter electronics and
rewind the 3 phase PM alternator to produce the voltage that you want and the RPM you
want to run at. Optionally, add a controller to the throttle to throttle down the
engine to reduce the output voltage for float charge.

Rewinding the star-shaped stator is trivially easy and can be done sitting in your
easy chair in just a few hours. I've done one of these for a friend and the results
were spectacular. From an EU1000 came 14 volts at 60 amps at full throttle, all in a
nice hand-held package.

John
---
John De Armond
See my website for my current email address
http://www.neon-john.com
Cleveland, Occupied TN
If we aren't supposed to eat animals, why are they made with meat?

Vaughn Simon

2007-06-06, 5:25 pm

"Ulysses" <eatmyspam@spamola.com/> wrote in message
news:136dp6eg6vkb112@corp.supernews.com...

Why reinvent the wheel? 48 V. battery chargers are common in the
telecommunications and golf cart worlds. My first Google hit is this:
http://www.batterystuff.com/battery...lt/all/JAC4820M

I know for a fact that there is surplus equipment out there, you just have to do
the legwork to find it.

If you really want to build a dumb bulk charger, your step-down transformer idea
will work if you just add an appropriately sized Variac to the line. Then you
will be able to adjust to whatever charge rate you want. The result would be
simple, primitive, & fairly efficient, but not idiot proof.

For a third idea, you could probably use a normal automotive alternator that
does not have an on-board regulator. A crude voltage adjustment circuit wired
to the field would allow you to manually set your charge current. Use a
junkyard alternator so little is lost if something (like a diode) blows, but I
would be surprised if it did.

wmbjkREMOVE@citlink.net

2007-06-06, 8:25 pm

On Wed, 06 Jun 2007 21:04:40 GMT, "Vaughn Simon"
<vaughnsimonHATESSPAM@att.FAKE.net> wrote:

>
>"Ulysses" <eatmyspam@spamola.com/> wrote in message
>news:136dp6eg6vkb112@corp.supernews.com...

>For a third idea, you could probably use a normal automotive alternator that
>does not have an on-board regulator.

IIRC he intends for this charger to be his main source. At 1kW or so
for a standard alternator, he better not be using much energy unless
he intends to run the generator a lot of hours. I modified one to get
2kW, it's fine for backup but I wouldn't want to use it as a primary
source.

> A crude voltage adjustment circuit wired
>to the field would allow you to manually set your charge current. Use a
>junkyard alternator so little is lost if something (like a diode) blows, but I
>would be surprised if it did.

I didn't have much luck using the standard diode bridge in an 80A,12V
Delco once I doubled its output to 24V. I used tougher diodes on an
external heat sink and mounted them in front of the enclosure blower.

Wayne

Ulysses

2007-06-06, 8:25 pm

"Neon John" <no@never.com> wrote in message
news:na5e63dh8pfdd3tq9snmgm8ib20clj2vcn@4ax.com...
> On Wed, 6 Jun 2007 09:10:05 -0700, "Ulysses" <eatmyspam@spamola.com/>
wrote:
>
alternator[color=darkred]
or[color=darkred]
would[color=darkred]
> I'm not aware of an off-the-shelf alternator but any car or preferably
heavy duty
> truck alternator will go to 48 volts with at most, a change in diode pack
to a higher
> voltage one and the proper regulator.

Is that something I should be able to get from an auto parts store? Every
time I go in one asking for something that's not for a specific vehicle I
get blank stares...

On my current version of my Cordless Battery
> Charger (TM)
> http://www.neon-john.com/Generator/CBC/CBC_home.htm (these are of an early
prototype
> but you get the idea), voltage of 12,24,48 or 72 are available at the turn
of a
> rotary switch.

If it's the same one you had posted a couple of years ago I didn't realize
that it was switchable for different voltages. I seem to remember you had a
3-stage charge in it. I'll take another look now....

>
volts[color=darkred]
48[color=darkred]
it[color=darkred]
speed[color=darkred]
>
> If your generator has an externally excited field with slip rings then
you'd want to
> change the field voltage instead of engine speed. Ripple from rectified
60 hz is
> considered harmful for batteries and the lower frequency, higher amplitude
ripple
> from a slowed generator would be worse.
>

It's a brushless generator head so does that still apply?

the[color=darkred]
15[color=darkred]
then[color=darkred]
done[color=darkred]
already.[color=darkred]
>
> You might also take a look at Progressive Dynamics. I know they offer a
48 volt
> version of their Intellipower that is quite reasonably priced.
>

OK, thanks.

can't[color=darkred]
voltage[color=darkred]
be[color=darkred]
>
> I didn't quite follow that. Did you remove the engine from the generator
head and
> belt drive it or use the engine to belt drive another generator.

The engine was wore out and to repair it would cost about $600 in parts so I
removed the piston, cam, belt, governor gear etc, greased the crankshaft
bearings, and attached a pulley to the flywheel. I'm running it with a
Honda GC135 with a belt (of course). The spacing on the carburator holes is
different on the two engines so I don't have Eco-Throttle--yet. If I'm
running a steady load such as a pump I just turn down the throttle til it
sounds about right and turn it up almost all the way to run power tools etc.
So far it works great but makes a funny, cyclic sound every few seconds. It
makes the same sound with oil in the ex-engine.

>
> An EU with bad electronics is still valuable. Toss the inverter
electronics and
> rewind the 3 phase PM alternator to produce the voltage that you want and
the RPM you
> want to run at. Optionally, add a controller to the throttle to throttle
down the
> engine to reduce the output voltage for float charge.

Do you happen to know which wires are the output? I could not managed to
get a DC reading from any combination I tried.

>
> Rewinding the star-shaped stator is trivially easy and can be done sitting
in your
> easy chair in just a few hours. I've done one of these for a friend and
the results
> were spectacular. From an EU1000 came 14 volts at 60 amps at full
throttle, all in a
> nice hand-held package.

I've read many instances of people rewinding alternators and making wind
generator alternators and such from scratch and it bothers me that I don't
know how to do it. Is there some sort of Idiots Guide to rewinding
alternators?

>
> John
> ---
> John De Armond
> See my website for my current email address
> http://www.neon-john.com
> Cleveland, Occupied TN
> If we aren't supposed to eat animals, why are they made with meat?
>

Ulysses

2007-06-06, 9:25 pm

"Vaughn Simon" <vaughnsimonHATESSPAM@att.FAKE.net> wrote in message
news:IjF9i.60981$Sa4.10695@bgtnsc05-news.ops.worldnet.att.net...
>
> "Ulysses" <eatmyspam@spamola.com/> wrote in message
> news:136dp6eg6vkb112@corp.supernews.com...
>
> Why reinvent the wheel? 48 V. battery chargers are common in the
> telecommunications and golf cart worlds. My first Google hit is this:
> http://www.batterystuff.com/battery...lt/all/JAC4820M
>
> I know for a fact that there is surplus equipment out there, you just have
to do
> the legwork to find it.
>

Golf carts eh? I did find something about phone equipment but they wanted a
lot of $$$ for it. I looked on ebay and didn't find any bargains so I
figure if it's not on ebay it doesn't exist ;-)

> If you really want to build a dumb bulk charger, your step-down
transformer idea
> will work if you just add an appropriately sized Variac to the line. Then
you
> will be able to adjust to whatever charge rate you want. The result would
be
> simple, primitive, & fairly efficient, but not idiot proof.

I'm probably the only idiot that will be using it so as long as I don't fall
asleep while the batteries are charging I should be OK.

>
> For a third idea, you could probably use a normal automotive alternator
that
> does not have an on-board regulator. A crude voltage adjustment circuit
wired
> to the field would allow you to manually set your charge current. Use a
> junkyard alternator so little is lost if something (like a diode) blows,
but I
> would be surprised if it did.
>
>

Ulysses

2007-06-06, 9:25 pm

<wmbjkREMOVE@citlink.net> wrote in message
news:ilfe63tv5u5gnifppb582biabanjrn620q@4ax.com...
> On Wed, 06 Jun 2007 21:04:40 GMT, "Vaughn Simon"
> <vaughnsimonHATESSPAM@att.FAKE.net> wrote:
>
>
that[color=darkred]
>
> IIRC he intends for this charger to be his main source. At 1kW or so
> for a standard alternator, he better not be using much energy unless
> he intends to run the generator a lot of hours. I modified one to get
> 2kW, it's fine for backup but I wouldn't want to use it as a primary
> source.

Yes. I figure that a typical 65 amp alternator would only put out about 15
amps at the most so I think I'd need a 200 amp unit to get any fast charge
rates but since I just happen to have a 65 amp, 12 volt alternator on hand I
guess it's worth a try. For that matter I could attach it to the same base
as my Ex-eu2000 and switch the belt back and forth as needed. I took the
alternator apart yesterday and it was not obvious to me how to bypass the
voltage regulator so I need to find that Delco web site again....

>
but I[color=darkred]
>
> I didn't have much luck using the standard diode bridge in an 80A,12V
> Delco once I doubled its output to 24V. I used tougher diodes on an
> external heat sink and mounted them in front of the enclosure blower.

If you doubled the voltage wouldn't the overall power output still be the
same? Are the diodes rated for such a low voltage?

>
> Wayne

Ulysses

2007-06-06, 9:25 pm

PFflyer

2007-06-07, 3:25 am

Inverter generators have a three phase alternator, DC rectified with filter
cap. This is similar to automobile alternator except they are using
permanent magnets for the field generation. Engine speed can be used for
alternator output control although the actual dc voltage control is not too
important as long as it above a minimum required for sinewave peak voltage
and lower then the breakdown limit of the inverter switching FET's.

Without engine speed control the D.C. can approach 300 vdc. The electronic
inverter pulse width modulates the dc output to generate a pretty clean and
stable 120 vac, 60 Hz output. The minimum DC voltage needs to stay above
about 175 vdc in order to make the peak of the 120 vac sine wave (169 v plus
some margin for switching loss). When you turn on the 'energy saving'
control, the regulator adjusts the engine speed to produce close to this 175
vdc minimum. It saves gas but it takes about a half a second for the engine
speed control to react to sudden load demands which usually means a short
period of peak clipped sinewave output.

If the Outback MX Solar charge controller could handle 300 vdc it could be
used, but it is limited to about 120 vdc input. Perhaps the Outback MX
solar charger could be modified with higher breakdown voltage FET's to
handle the higher input dc voltages.

You would have to get a DC buck switcher power converter to take the 300 vdc
down to 54 vdc to 60 vdc needed to charge the batteries. It should have
current limit and voltage regulations.

I don't know if anybody sell something like this. I though about building
one to put on my Yamaha EF3000 generator but decided it was too much work to
save maybe 5% to 10% conversion loss on my Trace SW4048 inverter chargers.

Regards,
RC

"Ulysses" <eatmyspam@spamola.com/> wrote in message
news:136dp6eg6vkb112@corp.supernews.com...
> Hi.
>
> Being very unhappy with using the built-in chargers in my new Outback
> inverters I'm considering using a small engine to run a 48 volt alternator
> for charging my battery bank but I can't seem to find any. Are these
> standard equipment on some kind of industrial machines such as fork lifts
> or
> tractors or whatever? Anyone have any links? I'm thinking 40-50 amps
> would
> probably be about right.
>
> I'm also considering various chargers that could be ran from a generator.
> It turns out that if a 2:1 step-down transformer was used 1/2 of 115 volts
> just happens to be almost exactly the right voltage for bulk charging a 48
> volt bank. After rectifying this will probably change but I'm thinking it
> might be possible to adjust the voltage by simply changing the engine
> speed
> a little. Equalization might also be possible.
>
> I looked at 48 volt battery chargers and Iota with the IQ4 seems to be the
> best choice (that's affordable anyway) but their 48 volt charger is only
> 15
> amps unless you get two 24 volt chargers and connect them in series and
> then
> it starts getting pricy again. Building a power supply to feed into the
> MX60 charge controller does not seem to be an option but if it could be
> done
> then the 3-stage charging and equalization would all be figured out
> already.
>
> I turned my first Honda eu2000 into a belt-drive generator head but I
> can't
> seem to find the DC output going to the inverter. I don't know the
> voltage
> that it uses but I figured it was worth a look on the off-chance it might
> be
> in the right range.
>
> Thanks.
>
>
>

Neon John

2007-06-07, 3:25 am

On Wed, 6 Jun 2007 17:44:48 -0700, "Ulysses" <eatmyspam@spamola.com/> wrote:

>
>heavy duty
>to a higher
>
>Is that something I should be able to get from an auto parts store? Every
>time I go in one asking for something that's not for a specific vehicle I
>get blank stares...

You must be going to AutoZombie :-) You need to find a locally owned store where, if
the guy doesn't know, will at least invite you to thumb through the catalog. The
NAPA store is like that in Cleveland.

I don't know if the diode pack is available or not. MY approach is to order three
case-to-cathode and 3 case-to-anode diodes from Digikey or whatever, along with some
heat sink, split the heat sink into a positive side and a negative side, mount the
diodes, hook 'em up to the alternator stator and mount the heat sinks where they'll
get plenty of air.

On the voltage regulator side, you simply use a standard 12 volt regulator - I like
the Delco internal regulators from the 70s-80s era. My reference vehicle is my old
79 El Camino because I know the alternator had the kind of regulator I want.

I can't seem to easily locate a photo of this regulator by googling so words will
have to do. It has a couple of screw-down internal connections and a couple of spade
lug connectors for external wiring.

One of the screw-down terminals is ground and the other goes to one brush. The other
brush gets 12 volts. The regulator controls field current by sinking current to
ground through that brush.

For the outside terminals, there is an "I" terminal or ignition. This terminal
powers up the regulator. There is an "S" or "sense" terminal that senses the system
voltage. The regulator excites the field to whatever degree necessary to keep this
sense terminal at 13.8 volts, plus or minus. There may be another terminal on some
regulators, the "L" terminal that goes to the charge light.

Those Delco boys were clever. If there's no connection to the S terminal then the
regulator will sense the I terminal. It can also get both its operating voltage and
sensing from the L terminal, though the regulation is poor because of the idiot light
in the circuit.

All we have to do to achieve a different voltage is build a simple 2 resistor voltage
divider. The two resistors are connected in series. One end is grounded and the
other goes to the high voltage to be regulated. The Sense lead goes to the junction
of the two. The resistance values are arranged so that when the high voltage (say,
48 volts) is at the correct voltage, the voltage the Sense lead sees is 13.8. Viola!
Instant 48 volt regulator.

I mount the regulator external to the alternator to get it out of all that heat. It
goes to a small piece of aluminum heatsink. Only minimal heat sinking is necessary,
as the regulator doesn't get hot at all.

I set the divider up so that one resistor is fixed and the other leg is a combo of a
fixed and a variable resistor (pot). That way I can trim the voltage to what I
want.

Given that GM replacement internal regulators seldom cost more than $10, this is a
dirt-cheap method of regulation. Just make sure you get the standard replacement
regulator for say, a 1979 El Camino and not a one-wire or other fancied-up version.
>
> On my current version of my Cordless Battery
>prototype
>of a
>
>If it's the same one you had posted a couple of years ago I didn't realize
>that it was switchable for different voltages. I seem to remember you had a
>3-stage charge in it. I'll take another look now....

I haven't updated my site in a LONG time in that area. My current version uses a
custom digital controller based on a BASIC stamp. There's a rotary knob that selects
the desired voltage using a multi-resistor voltage divider just like I described
above. I took it all the way to 72 volts so I could charge my old CitiCar (electric
car) batteries.

John
>
>
>volts
>48
>it
>speed
>you'd want to
>60 hz is
>ripple
>
>It's a brushless generator head so does that still apply?
>
>
>the
>15
>then
>done
>already.
>48 volt
>
>OK, thanks.
>
>
>can't
>voltage
>be
>head and
>
>The engine was wore out and to repair it would cost about $600 in parts so I
>removed the piston, cam, belt, governor gear etc, greased the crankshaft
>bearings, and attached a pulley to the flywheel. I'm running it with a
>Honda GC135 with a belt (of course). The spacing on the carburator holes is
>different on the two engines so I don't have Eco-Throttle--yet. If I'm
>running a steady load such as a pump I just turn down the throttle til it
>sounds about right and turn it up almost all the way to run power tools etc.
>So far it works great but makes a funny, cyclic sound every few seconds. It
>makes the same sound with oil in the ex-engine.
>
>electronics and
>the RPM you
>down the
>
>Do you happen to know which wires are the output? I could not managed to
>get a DC reading from any combination I tried.
>
>in your
>the results
>throttle, all in a
>
>I've read many instances of people rewinding alternators and making wind
>generator alternators and such from scratch and it bothers me that I don't
>know how to do it. Is there some sort of Idiots Guide to rewinding
>alternators?
>
>
---
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Cleveland, Occupied TN
Save the whales, collect the whole set!

Neon John

2007-06-07, 3:25 am

On Wed, 6 Jun 2007 18:28:06 -0700, "Ulysses" <eatmyspam@spamola.com/> wrote:

>It just occured to me that my father-in-law has a homemade air compressor
>that uses a 120 VDC motor. Do you think it would be possible to use that
>motor as a DC generator? And maybe control the voltage with engine speed?
>I have no idea at the moment how powerful a motor it is but it must be
>fairly substantial for a compressor. I was thinking of trying to run it (as
>an air compressor) on 48 volts which would probably require a gear
>reduction but I don't usually need a lot of air at once.

Sure. It's probably a 90vdc motor with a permanent magnet field. He's running it on
rectified AC which is overspeeding it a little but obviously not enough to hurt.
It'll work fine as a generator. You MIGHT need to re-phase the brushes to cut down
on commutator sparking. Just have to try and see.

John
---
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Cleveland, Occupied TN
Save the whales, collect the whole set!

Vaughn Simon

2007-06-07, 9:25 am

"Ulysses" <eatmyspam@spamola.com/> wrote in message
news:136eoar1rgolnf6@corp.supernews.com...
>
> If you doubled the voltage wouldn't the overall power output still be the
> same? Are the diodes rated for such a low voltage?

I have virtually no experience with alternator diodes, but for decades now
there has been little economic reason to make a power diode with a PIV rating
less than 100. Several companies years ago used to make a box which (I assume)
simply bypassed the regulator so you could run power tools from your vehicle
alternator. (That said, it never seemed like a good idea and I never used one.)

Vaughn

>
>
>
>

scott

2007-06-07, 5:25 pm

"Vaughn Simon" <vaughnsimonHATESSPAM@att.FAKE.net> wrote in
news:TKQ9i.62701$Sa4.53304@bgtnsc05-news.ops.worldnet.att.net:

>
> "Ulysses" <eatmyspam@spamola.com/> wrote in message
> news:136eoar1rgolnf6@corp.supernews.com...
>
> I have virtually no experience with alternator diodes, but for
> decades now
> there has been little economic reason to make a power diode with a PIV
> rating less than 100. Several companies years ago used to make a box
> which (I assume) simply bypassed the regulator so you could run power
> tools from your vehicle alternator. (That said, it never seemed like
> a good idea and I never used one.)
>
> Vaughn
>

Hi
Some of the newer alternators out there for American cars now have
"avalanche" diodes that are supposed to act like a high power zener diode
and suppress high voltage spikes. If I recall right they operated at about
45 volts. You may want to check with a knowledgeable alternator rebuilder
when you select your parts if you plan on boosting voltage output.
Scott

Ulysses

2007-06-07, 5:25 pm

"PFflyer" <ron.craig@adelphia.net> wrote in message
news:ApidnVUgbP7M5_rbnZ2dnUVZ_segnZ2d@adelphia.com...
> Inverter generators have a three phase alternator, DC rectified with
filter
> cap. This is similar to automobile alternator except they are using
> permanent magnets for the field generation.

Thanks for the explanation. I'd read that they directly produce DC but the
first time I took one apart it sure *looked* like an alternator except for
the permanent magnets.

Engine speed can be used for
> alternator output control although the actual dc voltage control is not
too
> important as long as it above a minimum required for sinewave peak voltage
> and lower then the breakdown limit of the inverter switching FET's.
>
> Without engine speed control the D.C. can approach 300 vdc. The
electronic
> inverter pulse width modulates the dc output to generate a pretty clean
and
> stable 120 vac, 60 Hz output. The minimum DC voltage needs to stay above
> about 175 vdc in order to make the peak of the 120 vac sine wave (169 v
plus
> some margin for switching loss). When you turn on the 'energy saving'
> control, the regulator adjusts the engine speed to produce close to this
175
> vdc minimum. It saves gas but it takes about a half a second for the
engine
> speed control to react to sudden load demands which usually means a short
> period of peak clipped sinewave output.
>
> If the Outback MX Solar charge controller could handle 300 vdc it could be
> used, but it is limited to about 120 vdc input. Perhaps the Outback MX
> solar charger could be modified with higher breakdown voltage FET's to
> handle the higher input dc voltages.
>
> You would have to get a DC buck switcher power converter to take the 300
vdc
> down to 54 vdc to 60 vdc needed to charge the batteries. It should have
> current limit and voltage regulations.
>
> I don't know if anybody sell something like this. I though about building
> one to put on my Yamaha EF3000 generator but decided it was too much work
to
> save maybe 5% to 10% conversion loss on my Trace SW4048 inverter chargers.
>
> Regards,
> RC
>
> "Ulysses" <eatmyspam@spamola.com/> wrote in message
> news:136dp6eg6vkb112@corp.supernews.com...
alternator[color=darkred]
lifts[color=darkred]
generator.[color=darkred]
volts[color=darkred]
48[color=darkred]
it[color=darkred]
the[color=darkred]
might[color=darkred]
>
>

Ulysses

2007-06-07, 5:25 pm

"Neon John" <no@never.com> wrote in message
news:80ef63t8nhfgjtce004tdgb7bc1t29b8mt@4ax.com...
> On Wed, 6 Jun 2007 18:28:06 -0700, "Ulysses" <eatmyspam@spamola.com/>
wrote:
>
>
speed?[color=darkred]
(as[color=darkred]
>
> Sure. It's probably a 90vdc motor with a permanent magnet field. He's
running it on
> rectified AC which is overspeeding it a little but obviously not enough to
hurt.
> It'll work fine as a generator. You MIGHT need to re-phase the brushes to
cut down
> on commutator sparking. Just have to try and see.

OK then. That sounds like the simplest solution at the moment. It's about
time for my wife to drop by and visit her parents anyway ;-)

>
> John
> ---
> John De Armond
> See my website for my current email address
> http://www.neon-john.com
> http://www.johndearmond.com <-- best little blog on the net!
> Cleveland, Occupied TN
> Save the whales, collect the whole set!
>

BobG

2007-06-07, 8:25 pm

> I'm considering using a small engine to run a 48 volt alternator
> for charging my battery bank but I can't seem to find any.
=============================================
Look at amplepower.com

Ulysses

2007-06-12, 5:25 pm

"Ulysses" <eatmyspam@spamola.com/> wrote in message
news:136dp6eg6vkb112@corp.supernews.com...
> Hi.
>
> Being very unhappy with using the built-in chargers in my new Outback
> inverters I'm considering using a small engine to run a 48 volt alternator
> for charging my battery bank but I can't seem to find any. Are these
> standard equipment on some kind of industrial machines such as fork lifts
or
> tractors or whatever? Anyone have any links? I'm thinking 40-50 amps
would
> probably be about right.
>
>

For posterity (and future Googlers) I found some permanent magnet
alternators on eBay with various outputs from 12 to 120(?) volts. The
seller's name is gazz611 and this link is for the eBay store:

http://search.ebay.com/_W0QQsassZqaz661

I still need to sort it all out but it looks like it might work for my
purposes. Meanwhile I have disabled the ACIinput on my Outback Inverter #1
and the Inverter Output on Inverter #2 so I'm now running everything all the
time from #1 and using #2 for battery charging only. This is a big
improvement as long as nobody turns on anything while the well pump is
running. Apparently the maximum charge rate on the inverter/charger is only
20 amps. I thought they put out more than that. I paralleled the outputs
on my 5000 watt generator so I have a balanced load on 120 volts. So far so
good. I don't have to push any buttons now when I start my generator unless
I want to use a smaller genny to charge at a lower rate.

wmbjkREMOVE@citlink.net

2007-06-13, 9:25 am

On Tue, 12 Jun 2007 11:41:19 -0700, "Ulysses" <eatmyspam@spamola.com/>
wrote:

>For posterity (and future Googlers) I found some permanent magnet
>alternators on eBay with various outputs from 12 to 120(?) volts. The
>seller's name is gazz611 and this link is for the eBay store:
>
>http://search.ebay.com/_W0QQsassZqaz661

Please post the results if you try it. I briefly considered getting
one but find that whole "hydrogen" appliances outfit kinda out-there.
Some of their wind turbine claims are laughable and I wouldn't be
surprised if the alternator specs are just as useful. For instance,
consider how small the bearings are in that little alternator, and the
difference between what it was designed to produce and what they're
claiming for it. Plus, it's really pricey compared to a standard
alternator which has the advantage of field control. Still, it might
be worth a try if you can get a lower Ebay price.

Wayne

Ulysses

2007-06-13, 1:25 pm

<wmbjkREMOVE@citlink.net> wrote in message
news:jotv63h4j102br6b3agsu8utn8vdjknp5d@4ax.com...
> On Tue, 12 Jun 2007 11:41:19 -0700, "Ulysses" <eatmyspam@spamola.com/>
> wrote:
>
>
> Please post the results if you try it. I briefly considered getting
> one but find that whole "hydrogen" appliances outfit kinda out-there.
> Some of their wind turbine claims are laughable and I wouldn't be
> surprised if the alternator specs are just as useful. For instance,
> consider how small the bearings are in that little alternator, and the
> difference between what it was designed to produce and what they're
> claiming for it. Plus, it's really pricey compared to a standard
> alternator which has the advantage of field control. Still, it might
> be worth a try if you can get a lower Ebay price.
>
> Wayne

This is why I post stuff like this--so people like you who know more than me
can point out things that hadn't even occured to me yet. I didn't look at
them hard enough yet to notice small bearings and such and yes, they do seem
rather pricey. But compared to all of the alternatives I've found so far
for charging my 48 volt battery bank it might end up costing less assuming I
can run it from an engine I already have. I'm not sure what you meant by
"hydrogen." I think I'd better take another look.

In any case these are the *only* 48 volt alternators I've found so far that
were "off-the-shelf" and not custom built for lots of $$$.

Meanwhile I reconfigured my Outback system so everything is running from
Inverter #1 and the autotransformer and #2 is being used only for charging.
At the moment I have my cheap Chinese 2000 watt genny charging at 1.5 kW and
it seems fine and the genny does not appear to be overloaded.

Here's something weird I discovered yesterday: I may have mentioned that I
made my old Honda eu2000 a belt-drive generator head and as yet it does not
have Eco-Throttle. Well, when I connected it to my Outback #2 for battery
charging it was charging at whatever rate it could according to what the
throttle speed was set at: faster engine speed produced a higher charge rate
and vice versa. It looks like I don't even need the Eco-Throttle, at least
not for this purpose. I had assumed that it would overload the genny at
startup if I did not have the throttle set almost all the way up.

>

Ulysses

2007-06-13, 1:25 pm

"Ulysses" <eatmyspam@spamola.com/> wrote in message
news:13709bd4cbkdee6@corp.supernews.com...
>
> <wmbjkREMOVE@citlink.net> wrote in message
> news:jotv63h4j102br6b3agsu8utn8vdjknp5d@4ax.com...
>
> This is why I post stuff like this--so people like you who know more than
me
> can point out things that hadn't even occured to me yet. I didn't look at
> them hard enough yet to notice small bearings and such and yes, they do
seem
> rather pricey. But compared to all of the alternatives I've found so far
> for charging my 48 volt battery bank it might end up costing less assuming
I
> can run it from an engine I already have. I'm not sure what you meant by
> "hydrogen." I think I'd better take another look.
>
> In any case these are the *only* 48 volt alternators I've found so far
that
> were "off-the-shelf" and not custom built for lots of $$$.
>
> Meanwhile I reconfigured my Outback system so everything is running from
> Inverter #1 and the autotransformer and #2 is being used only for
charging.
> At the moment I have my cheap Chinese 2000 watt genny charging at 1.5 kW
and
> it seems fine and the genny does not appear to be overloaded.

Sorry about the redundancy. I think I need to give my poor little brain a
rest.

>
> Here's something weird I discovered yesterday: I may have mentioned that I
> made my old Honda eu2000 a belt-drive generator head and as yet it does
not
> have Eco-Throttle. Well, when I connected it to my Outback #2 for battery
> charging it was charging at whatever rate it could according to what the
> throttle speed was set at: faster engine speed produced a higher charge
rate
> and vice versa. It looks like I don't even need the Eco-Throttle, at
least
> not for this purpose. I had assumed that it would overload the genny at
> startup if I did not have the throttle set almost all the way up.
>
>
>

sylvan butler

2007-06-13, 5:25 pm

On Wed, 13 Jun 2007 10:10:54 -0700, Ulysses <eatmyspam@spamola.com/> wrote:
> In any case these are the *only* 48 volt alternators I've found so far that
> were "off-the-shelf" and not custom built for lots of $$$.

I think pretty much any alternator will produce 48v (or the 56v to 60v
you need to charge the batteries). The issue might be the built-in
diodes not happy with the higher voltage.

But considering the price of buying the special OTS 48v units vs any old
12v alternator and learning how to replace the internal diodes with
external higher-voltage ones...

sdb
--
What's seen on your screen? http://pcscreenwatch.com
sdbuse1 on mailhost bigfoot.com

Neon John

2007-06-13, 9:25 pm

On Wed, 13 Jun 2007 10:10:54 -0700, "Ulysses" <eatmyspam@spamola.com/> wrote:

>This is why I post stuff like this--so people like you who know more than me
>can point out things that hadn't even occured to me yet. I didn't look at
>them hard enough yet to notice small bearings and such and yes, they do seem
>rather pricey. But compared to all of the alternatives I've found so far
>for charging my 48 volt battery bank it might end up costing less assuming I
>can run it from an engine I already have. I'm not sure what you meant by
>"hydrogen." I think I'd better take another look.
>
>In any case these are the *only* 48 volt alternators I've found so far that
>were "off-the-shelf" and not custom built for lots of $$$.

Don't obsess over the nameplate voltage rating of an alternator or generator. This
is strictly nominal, a design point.

The output voltage is the algebraic product of the field strength and the speed
(RPM). Increase either and you increase the output voltage. With a permanent magnet
device, your only parameter is speed.

The second important concept is that input torque is directly proportional to output
current and vice versa.

Once you understand this, there are many options available. The (practically) linear
relationship between speed and voltage, and torque and current means that you can
easily control either mechanically. If you want to limit the output current of a
generator, simply limit the torque supplied from the prime mover. If you want to
change voltage then simply change speed. It really is that easy.

At 48 volts you have an almost unlimited choice of options. There are zillions of 48
volt permanent magnet DC motors in use in fork lifts. Increasingly the industry is
moving to "brushless DC motors" (think 3 phase synchronous motors with permanent
magnet fields) which are even better, as there is no commutator or brushes to mess
with.

There are zillions of industrial DC motors about in sizes up to thousands of HP. All
make excellent generators and are dirt cheap on the surplus market, bringing little
more than their scrap value. Within reason, ignore the voltage rating and look at
the current rating. If you slow the rotation and/or weaken the field you can
generate at least that much current at 48 volts even if the motor was originally
rated at 90, 120 or 250 volts DC. The higher voltage motors are, of course, much
larger and less efficient because of the high aero and other losses but they'll work.

A common 3 phase AC motor makes an excellent induction generator. Connect sufficient
capacitors across the leads to supply the necessary magnetizing current, apply a
little DC to get things going and there you are. A 6 diode, three phase rectifier
completes the package. Google "induction generator" for more information.

You can even hack the squirrel cage rotor in said motor and make it a permanent
magnet generator. Lots of Tesla coilers do this to convert the motor to a "salient
pole synchronous motor" that runs at exactly 3600 RPM. That same motor is an
excellent generator. Google "salient pole tesla coil" and see what pops up.

Another good generator is the surplus aircraft generators that are being widely sold
as welding generators. Typically 24 or 48 volt rated and capable of from 100 to 500
amps. These go in the $100-300 dollar range.

Once you become capable of lashing an engine to some sort of device, you've done the
hard part. Finding something to drive with that engine is easy.

Find something that you're interested in potentially using, then come back here and
ask. Just don't get ripped off by these shady "alternative energy" scammers.

John
---
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Cleveland, Occupied TN
Unable to locate Coffee -- Operator Halted!

Ulysses

2007-06-14, 8:25 pm

"Neon John" <no@never.com> wrote in message
news:at7173tf0sa33qr0r57o6oepcsfcl95ep9@4ax.com...
> On Wed, 13 Jun 2007 10:10:54 -0700, "Ulysses" <eatmyspam@spamola.com/>
wrote:
>
>
me[color=darkred]
at[color=darkred]
seem[color=darkred]
assuming I[color=darkred]
that[color=darkred]
>
> Don't obsess over the nameplate voltage rating of an alternator or
generator. This
> is strictly nominal, a design point.
>
> The output voltage is the algebraic product of the field strength and the
speed
> (RPM). Increase either and you increase the output voltage. With a
permanent magnet
> device, your only parameter is speed.
>
> The second important concept is that input torque is directly proportional
to output
> current and vice versa.
>
> Once you understand this, there are many options available. The
(practically) linear
> relationship between speed and voltage, and torque and current means that
you can
> easily control either mechanically. If you want to limit the output
current of a
> generator, simply limit the torque supplied from the prime mover. If you
want to
> change voltage then simply change speed. It really is that easy.
>
> At 48 volts you have an almost unlimited choice of options. There are
zillions of 48
> volt permanent magnet DC motors in use in fork lifts. Increasingly the
industry is
> moving to "brushless DC motors" (think 3 phase synchronous motors with
permanent
> magnet fields) which are even better, as there is no commutator or brushes
to mess
> with.
>
> There are zillions of industrial DC motors about in sizes up to thousands
of HP. All
> make excellent generators and are dirt cheap on the surplus market,
bringing little
> more than their scrap value. Within reason, ignore the voltage rating and
look at
> the current rating. If you slow the rotation and/or weaken the field you
can
> generate at least that much current at 48 volts even if the motor was
originally
> rated at 90, 120 or 250 volts DC. The higher voltage motors are, of
course, much
> larger and less efficient because of the high aero and other losses but
they'll work.
>
> A common 3 phase AC motor makes an excellent induction generator. Connect
sufficient
> capacitors across the leads to supply the necessary magnetizing current,
apply a
> little DC to get things going and there you are. A 6 diode, three phase
rectifier
> completes the package. Google "induction generator" for more information.
>
> You can even hack the squirrel cage rotor in said motor and make it a
permanent
> magnet generator. Lots of Tesla coilers do this to convert the motor to a
"salient
> pole synchronous motor" that runs at exactly 3600 RPM. That same motor is
an
> excellent generator. Google "salient pole tesla coil" and see what pops
up.
>
> Another good generator is the surplus aircraft generators that are being
widely sold
> as welding generators. Typically 24 or 48 volt rated and capable of from
100 to 500
> amps. These go in the $100-300 dollar range.
>
> Once you become capable of lashing an engine to some sort of device,
you've done the
> hard part. Finding something to drive with that engine is easy.

Ok then. That part I have accomplished twice so far.

I got the homemade air compressor from my father-in-law but it does not have
a permanent magnet DC motor. It is a GE 120 volt motor rated something like
6.6 amps. So, if the coils were excited by a small DC current they would
engergize and it could be used as a generator? I think I need a lot more
amps that what the plate on the motor says.

Thanks for all the info. I have a lot of searching and reading to do
now....

>
> Find something that you're interested in potentially using, then come back
here and
> ask. Just don't get ripped off by these shady "alternative energy"
scammers.

Well, when something sounds too good to be true...

>
> John
> ---
> John De Armond
> See my website for my current email address
> http://www.neon-john.com
> http://www.johndearmond.com <-- best little blog on the net!
> Cleveland, Occupied TN
> Unable to locate Coffee -- Operator Halted!
>

Ulysses

2007-06-14, 8:25 pm

"sylvan butler" <ZsdbUse1+noZs_0706@Zbigfoot.Zcom.invalid> wrote in message
news:slrnf70mgq.6tj.ZsdbUse1+noZs_0706@sdba64.internal...
> On Wed, 13 Jun 2007 10:10:54 -0700, Ulysses <eatmyspam@spamola.com/>
wrote:
that[color=darkred]
>
> I think pretty much any alternator will produce 48v (or the 56v to 60v
> you need to charge the batteries). The issue might be the built-in
> diodes not happy with the higher voltage.
>
> But considering the price of buying the special OTS 48v units vs any old
> 12v alternator and learning how to replace the internal diodes with
> external higher-voltage ones...

If I can find a wiring diagram I can do it. Or maybe if I just take it
apart and stare at it long enough...

If a 12 volt, 65 amp alternator will put out 15 amps at 48 volts then I'd
probably be better off than I am right now using a 5000 watt generator to
get 18 amps.

>
> sdb
> --
> What's seen on your screen? http://pcscreenwatch.com
> sdbuse1 on mailhost bigfoot.com

Ecnerwal

2007-06-14, 8:25 pm

In article <1373juj19s30q21@corp.supernews.com>,
"Ulysses" <eatmyspam@spamola.com/> wrote:

> If a 12 volt, 65 amp alternator will put out 15 amps at 48 volts then I'd
> probably be better off than I am right now using a 5000 watt generator to
> get 18 amps.

If you have the power to drive it and diodes that will take it, no
particular reason that you should not be able to run 50-65 amps from it.
The wire size sets the amperage - within reasonable limits it does not
much care about voltage. If it's physically marginal I suppose it might
fall apart from more force, but heating-wise, the amps are the thing.

--
Cats, coffee, chocolate...vices to live by

wmbjkREMOVE@citlink.net

2007-06-14, 8:25 pm

On Wed, 13 Jun 2007 10:10:54 -0700, "Ulysses" <eatmyspam@spamola.com/>
wrote:

> I'm not sure what you meant by
>"hydrogen." I think I'd better take another look.

Main company site is here http://hydrogenappliances.com/. I had a
chuckle reading the comment about slip rings on wind turbines being
"old fashioned".

>In any case these are the *only* 48 volt alternators I've found so far that
>were "off-the-shelf" and not custom built for lots of $$$.

You can use any surplus alternator. I used a large-case Delco (like
you see on an ambulance or old-boat Cadillac. You can often get them
for $5 at a wrecker. Unless they're rusted up from being out in the
rain or some such, usually the only thing that's wrong with them is a
dead regulator or rectifier. Both are cheap to replace, although you'd
be wise to use an external regulator and a better rectifier IMO. FWIW,
when mine was cranked up to 75A, I had some trouble with the heat on
the stator wiring connections. They were crimped on and developed high
resistance after some hours. I plan to try a much more substantial
brushless unit that was originally 24V... whenever I get around to it.

Wayne

clare at snyder.on.ca

2007-06-15, 3:25 am

On Thu, 14 Jun 2007 16:30:08 -0700, "Ulysses" <eatmyspam@spamola.com/>
wrote:

>
>"sylvan butler" <ZsdbUse1+noZs_0706@Zbigfoot.Zcom.invalid> wrote in message
>news:slrnf70mgq.6tj.ZsdbUse1+noZs_0706@sdba64.internal...
>wrote:
>that
>
>If I can find a wiring diagram I can do it. Or maybe if I just take it
>apart and stare at it long enough...
>
>If a 12 volt, 65 amp alternator will put out 15 amps at 48 volts then I'd
>probably be better off than I am right now using a 5000 watt generator to
>get 18 amps.
>
It'll put out very close to 65 amps at 48 volts.[color=darkred]
>

--
Posted via a free Usenet account from http://www.teranews.com

JeB

2007-06-15, 3:25 am

>>
>
>If I can find a wiring diagram I can do it. Or maybe if I just take it
>apart and stare at it long enough...
>
>If a 12 volt, 65 amp alternator will put out 15 amps at 48 volts then I'd
>probably be better off than I am right now using a 5000 watt generator to
>get 18 amps.
>

used to be you could buy gizmos to run your alternator basicly
unregulated and power 110v universal motors. I started building a
house that way, before the utility power arrived. As I recall it
didn't work all that well and it got hot ... but you can
experiment.

I also vaguely recall (homepower.org?) seeing some sort of manual
field adjustment for an alternator to give the amperage you want for
charging , I suppose something like that would work to get the 48+
vdc you want.

Todd

2007-06-15, 1:25 pm

On Jun 6, 8:02 pm, "Ulysses" <eatmys...@spamola.com/> wrote:[color=darkred]
> <wmbjkREM...@citlink.net> wrote in message
>
> news:ilfe63tv5u5gnifppb582biabanjrn620q@4ax.com...
>
>
>
>
>
> that
>
>
> Yes. I figure that a typical 65 amp alternator would only put out about 15
> amps at the most so I think I'd need a 200 amp unit to get any fast charge
> rates but since I just happen to have a 65 amp, 12 volt alternator on hand I
> guess it's worth a try. For that matter I could attach it to the same base
> as my Ex-eu2000 and switch the belt back and forth as needed. I took the
> alternator apart yesterday and it was not obvious to me how to bypass the
> voltage regulator so I need to find that Delco web site again....
>
>
>
>
>
> but I
>
>
> If you doubled the voltage wouldn't the overall power output still be the
> same? Are the diodes rated for such a low voltage?
>
>
>

What are you using for an inverter? If it will take a 48V input, just
get any car alternator. Make your battery bank 48V by putting 4
batteries in series. I can get well over 60V open circuit on my little
alternator with just 4W into the armature.

The alternator I'm now using is a tiny 4 phase model I picked up at a
junk yard for $10. I remove the controller. I hook a variable DC power
supply to the two armature wires. I take the DC output from the two
wires coming from the 8 diode bridge.

I don't have an inverter that will take a high input voltage so I'm
using 12V batteries in parallel. I use a PV charge controller to buck
the 50V open circuit DC from the alternator down to the 14.5 nominal
charging voltage. Actually my charge controller has all the built in
circuity to do the 3 level charge and the monthly equilization.

I saw an earlier warning about the ripple on a 60 cycle alternator.
I've only seen 3 and 4 phase alternators. Since they're using all
phases in the output, there is very little ripple ... certainly not
enough for a battery bank to notice.

At the higher voltage (e.g. 24 or 48V) you'll be using less current,
have less loss in the wires, run smaller wires, and generally get
better performance.

I wish I had a 24 or 48V inverter.

Ulysses

2007-06-15, 1:25 pm

<clare at snyder.on.ca> wrote in message
news:86047399aajml9jjpiqsu8c73ba23upn8v@4ax.com...
> On Thu, 14 Jun 2007 16:30:08 -0700, "Ulysses" <eatmyspam@spamola.com/>
> wrote:
>
message[color=darkred]
far[color=darkred]
old[color=darkred]
> It'll put out very close to 65 amps at 48 volts.

Well then, that would be very suitable for a 675 Ah battery bank. That
would require about 8 HP I think. And maybe a cooling fan.

>
>
> --
> Posted via a free Usenet account from http://www.teranews.com
>

clare at snyder.on.ca

2007-06-15, 1:25 pm

On Fri, 15 Jun 2007 08:55:53 -0700, Todd <Todd@WithGLEE.com> wrote:

>I saw an earlier warning about the ripple on a 60 cycle alternator.
>I've only seen 3 and 4 phase alternators. Since they're using all
>phases in the output, there is very little ripple ... certainly not
>enough for a battery bank to notice.
>
>At the higher voltage (e.g. 24 or 48V) you'll be using less current,
>have less loss in the wires, run smaller wires, and generally get
>better performance.
>
>I wish I had a 24 or 48V inverter.

I've never SEEN a 60 cycle automotive alternator. Most are several
hundred hertz at charging speeds.

--
Posted via a free Usenet account from http://www.teranews.com

clare at snyder.on.ca

2007-06-15, 5:25 pm

On Fri, 15 Jun 2007 10:17:41 -0700, "Ulysses"
<therealulysses@yahoo.com> wrote:

>

>
>Well then, that would be very suitable for a 675 Ah battery bank. That
>would require about 8 HP I think. And maybe a cooling fan.
>
>
52 volts to charge a 48 volt battery, at 65 amps is 3.38KW.
Alternator efficiency (on a GOOD automotive unit) is just around the
70%, so 4.825 KW input is required. Sounds like 5 HP to me.

--
Posted via a free Usenet account from http://www.teranews.com

Ulysses

2007-06-15, 9:25 pm

<clare at snyder.on.ca> wrote in message
news:c8m573hkm9caqidqurj4bn49a8p8iuql0e@4ax.com...
> On Fri, 15 Jun 2007 10:17:41 -0700, "Ulysses"
> <therealulysses@yahoo.com> wrote:
>
>
> 52 volts to charge a 48 volt battery, at 65 amps is 3.38KW.
> Alternator efficiency (on a GOOD automotive unit) is just around the
> 70%, so 4.825 KW input is required. Sounds like 5 HP to me.
>
I figured it at 56 volts and gave myself a generous margin but 5.5 HP just
might be ideal.

Thanks.

> --
> Posted via a free Usenet account from http://www.teranews.com
>

wmbjkREMOVE@citlink.net

2007-06-16, 9:25 am

On Fri, 15 Jun 2007 18:31:59 -0700, "Ulysses"
<therealulysses@yahoo.com> wrote:

>I figured it at 56 volts and gave myself a generous margin but 5.5 HP just
>might be ideal.

You might read this http://www.homepower.com/files/promised/mark8.pdf
to compare your planning to their experience. I think you'll find that
a home-built setup won't be as efficient as you expect. Consider using
a somewhat larger engine and running it slower for more flexibility,
less noise, and longer life at the expense of slightly lower
efficiency. I went all the way up to 14hp to get an engine that had
electric start, pressure lubrication, and a proper oil filter. It was
bigger than I wanted but the price was right at $400some dollars
delivered. Here are two good sources for engines.
http://www.surpluscenter.com/engine...catname=engines
http://www.smallenginewarehouse.com/ You can use a vertical model if
you don't mind a little extra work making the mount. Verticals tend to
be substantially cheaper in the larger sizes.

Wayne

Ulysses

2007-06-16, 1:25 pm

<wmbjkREMOVE@citlink.net> wrote in message
news:45s7731pq2q5hamlrboslkbl1bfj0m2uq5@4ax.com...
> On Fri, 15 Jun 2007 18:31:59 -0700, "Ulysses"
> <therealulysses@yahoo.com> wrote:
>
>
just[color=darkred]
>
> You might read this http://www.homepower.com/files/promised/mark8.pdf
> to compare your planning to their experience. I think you'll find that
> a home-built setup won't be as efficient as you expect. Consider using
> a somewhat larger engine and running it slower for more flexibility,
> less noise, and longer life at the expense of slightly lower
> efficiency. I went all the way up to 14hp to get an engine that had
> electric start, pressure lubrication, and a proper oil filter. It was
> bigger than I wanted but the price was right at $400some dollars
> delivered. Here are two good sources for engines.
>
http://www.surpluscenter.com/engine...catname=engines
> http://www.smallenginewarehouse.com/ You can use a vertical model if
> you don't mind a little extra work making the mount. Verticals tend to
> be substantially cheaper in the larger sizes.
>
> Wayne

Yes. My experience with generators is that they generally are
marginally-powered. 9HP might work on a 5000 watt unit but 10 or 11 is
usually better. With my 65 amp alternator charging at 12 volts (13.X or
whatever) the engine could stall if a large load started on the inverter
that was attached to the batteries it was charging so I agree it's usually
better to go bigger on the engine. I'm also all in favor of running it at a
slower speed for longer engine life and less noise. I also tend to try
using whatever I have on hand too so sometimes it takes a bit more effort
and figuring. If I need to buy an engine I'm leaning towards getting one
with an electric start or at least low-oil shutdown so I can use a timer or
voltage sensing circuit to shut off the engine when the batteries are
charged. But first I need to accomplish getting the 48 volts + out of my 12
volt alternator.

Thanks for the links. I've bought a couple of engines from
smallenginewarehouse but I did not know about the other place.

Backing up a little it's strange but when an engine is running at 1800 rpm
it is not as noisy as if it's running at 3600 rpm and I'll bet the dB level
is the same. Just less explosions per second I guess.

Thanks also for the www.homepower link. I switched computers and was about
to go searching for that site again. Now if I can just find the site that
shows how the Delco alternator is put together.

Ulysses

2007-06-17, 8:25 pm

"Neon John" <no@never.com> wrote in message
news:nibf635mv66tv7p23f91iecg56kernpv0h@4ax.com...
> On Wed, 6 Jun 2007 17:44:48 -0700, "Ulysses" <eatmyspam@spamola.com/>
wrote:
>
pack[color=darkred]
Every[color=darkred]
>
> You must be going to AutoZombie :-) You need to find a locally owned
store where, if
> the guy doesn't know, will at least invite you to thumb through the
catalog. The
> NAPA store is like that in Cleveland.
>
> I don't know if the diode pack is available or not. MY approach is to
order three
> case-to-cathode and 3 case-to-anode diodes from Digikey or whatever, along
with some
> heat sink, split the heat sink into a positive side and a negative side,
mount the
> diodes, hook 'em up to the alternator stator and mount the heat sinks
where they'll
> get plenty of air.
>
> On the voltage regulator side, you simply use a standard 12 volt
regulator - I like
> the Delco internal regulators from the 70s-80s era. My reference vehicle
is my old
> 79 El Camino because I know the alternator had the kind of regulator I
want.
>
> I can't seem to easily locate a photo of this regulator by googling so
words will
> have to do. It has a couple of screw-down internal connections and a
couple of spade
> lug connectors for external wiring.

I just took my alternator apart. I pretty sure it's a Delco (7127?). The
regulator is as you described except the brushes appear to be an integral
part of the regulator assembly so I don't see how, on this particular unit,
how it could be relocated outside of the case.

>
> One of the screw-down terminals is ground and the other goes to one brush.
The other
> brush gets 12 volts. The regulator controls field current by sinking
current to
> ground through that brush.
>
> For the outside terminals, there is an "I" terminal or ignition. This
terminal
> powers up the regulator. There is an "S" or "sense" terminal that senses
the system
> voltage. The regulator excites the field to whatever degree necessary to
keep this
> sense terminal at 13.8 volts, plus or minus. There may be another
terminal on some
> regulators, the "L" terminal that goes to the charge light.

Mine are marked "F" and "R." At one time I knew what that meant because I
was using this alternator to charge 12 volt batteries. In any case it looks
an awful lot like the alternator in my '78 F350 but I'm not certain it's the
same. Probably very similar to the one in your '79 El Camino. Anyway,
which one would be "I" and which would be "S?"

>
> Those Delco boys were clever. If there's no connection to the S terminal
then the
> regulator will sense the I terminal. It can also get both its operating
voltage and
> sensing from the L terminal, though the regulation is poor because of the
idiot light
> in the circuit.
>
> All we have to do to achieve a different voltage is build a simple 2
resistor voltage
> divider. The two resistors are connected in series. One end is grounded
and the
> other goes to the high voltage to be regulated. The Sense lead goes to
the junction
> of the two. The resistance values are arranged so that when the high
voltage (say,
> 48 volts) is at the correct voltage, the voltage the Sense lead sees is
13.8. Viola!
> Instant 48 volt regulator.

Are we talking about a few ohms or a lot? From what you said I was thinking
of connecting, say, a 100K pot and fiddle with it until I got the right
reading and then measure the resistance. Or do I need a small value of pot?

>
> I mount the regulator external to the alternator to get it out of all that
heat. It
> goes to a small piece of aluminum heatsink. Only minimal heat sinking is
necessary,
> as the regulator doesn't get hot at all.
>
> I set the divider up so that one resistor is fixed and the other leg is a
combo of a
> fixed and a variable resistor (pot). That way I can trim the voltage to
what I
> want.
>
> Given that GM replacement internal regulators seldom cost more than $10,
this is a
> dirt-cheap method of regulation. Just make sure you get the standard
replacement
> regulator for say, a 1979 El Camino and not a one-wire or other fancied-up
version.
early[color=darkred]
turn[color=darkred]
realize[color=darkred]
had a[color=darkred]
>
> I haven't updated my site in a LONG time in that area. My current version
uses a
> custom digital controller based on a BASIC stamp. There's a rotary knob
that selects
> the desired voltage using a multi-resistor voltage divider just like I
described
> above. I took it all the way to 72 volts so I could charge my old CitiCar
(electric
> car) batteries.
>
> John
generator.[color=darkred]
a[color=darkred]
thinking[color=darkred]
rectified[color=darkred]
amplitude[color=darkred]
only[color=darkred]
and[color=darkred]
the[color=darkred]
be[color=darkred]
a[color=darkred]
might[color=darkred]
generator[color=darkred]
so I[color=darkred]
is[color=darkred]
etc.[color=darkred]
It[color=darkred]
and[color=darkred]
throttle[color=darkred]
sitting[color=darkred]
and[color=darkred]
don't[color=darkred]
> ---
> John De Armond
> See my website for my current email address
> http://www.neon-john.com
> http://www.johndearmond.com <-- best little blog on the net!
> Cleveland, Occupied TN
> Save the whales, collect the whole set!
>

Loren Amelang

2007-06-18, 1:25 pm

On Fri, 15 Jun 2007 18:42:07 -0700, "Ulysses"
<therealulysses@yahoo.com> wrote:

>"Neon John" <no@never.com> wrote in message
>news:nibf635mv66tv7p23f91iecg56kernpv0h@4ax.com...

>resistor voltage
>and the
>the junction
>voltage (say,
>13.8. Viola!
>
>Are we talking about a few ohms or a lot? From what you said I was thinking
>of connecting, say, a 100K pot and fiddle with it until I got the right
>reading and then measure the resistance. Or do I need a small value of pot?

I use a 25 ohm rheostat on a similar Delco, to charge a 24 volt bank,
but my alternator is only spinning around 3600 RPM. You don't actually
need a divider, I just use two terminals of the rheostat from +24 to
the field terminal. At maximum output the field current is about half
an amp, so you need serious current capacity from your rheostat. Such
things aren't as common as they used to be...

Loren

wmbjkREMOVE@citlink.net

2007-06-19, 5:25 pm

On Mon, 18 Jun 2007 11:07:07 -0700, Loren Amelang <loren@pacific.net>
wrote:

>On Fri, 15 Jun 2007 18:42:07 -0700, "Ulysses"
><therealulysses@yahoo.com> wrote:

>
>I use a 25 ohm rheostat on a similar Delco, to charge a 24 volt bank,
>but my alternator is only spinning around 3600 RPM. You don't actually
>need a divider, I just use two terminals of the rheostat from +24 to
>the field terminal. At maximum output the field current is about half
>an amp, so you need serious current capacity from your rheostat. Such
>things aren't as common as they used to be...

That's how I used to do it as well. But my rheostat (surplus, too much
resistance) couldn't be adjusted accurately, and the heat it
dissipated was bothersome inside an enclosure. So I switched to one of
these http://tinyurl.com/33flck. About $25US delivered, arrived in
about 2 weeks. Works slick, I've put perhaps 100 hours on it without
issue.

Wayne

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