Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 12-31-2020, 10:42 AM   #21
Badpuppy
Senior Member
 
Join Date: Dec 2017
Location: Guthrie, OK
Posts: 870
Default Re: 12v from 3 brush Ford generator

The "button" diodes (3 of them) are pressed into the deeper recesses of the aluminum rectifier heat sink in an alternator. A better choice for cutout mod is a stud mount type with heat sink compound for better heat transfer to the bus bar. Diode should be rated at least 25A. Use 12AWG for connection.

Example for negative ground -
https://www.ebay.com/itm/50-AMP-1000...-/121864495540

Positive ground type also available from the same seller.
Badpuppy is offline   Reply With Quote
Old 12-31-2020, 11:01 AM   #22
Sparky
Senior Member
 
Sparky's Avatar
 
Join Date: May 2010
Location: Rhode Island
Posts: 641
Default Re: 12v from 3 brush Ford generator

Quote:
Originally Posted by Badpuppy View Post
Math's ok but not the reasoning. If the gen actually is capable of 22A at 6V without melting then it is capable of 22A at 12V as well. This means if you get 132 watts output at 6V then you get 264 watts out at 12V. That's one reason for converting to 12V.
Yes, but jwmckenzie is generally correct if your total power requirement is unchanged when switching to 12V.

For example, it you have a total of 60 watts of power requirement on a 6V system, the generator has to provide 6 volts x 10 amps = 60W. Converting to 12 volts, if the 6V light bulbs are replaced with equivalent power 12V bulbs (and the coil), the total power requirement will still be 60W, and now the generator will need to supply only 5 amps; 12V x 5 amps = 60W.
Sparky is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 12-31-2020, 11:04 AM   #23
Sparky
Senior Member
 
Sparky's Avatar
 
Join Date: May 2010
Location: Rhode Island
Posts: 641
Default Re: 12v from 3 brush Ford generator

Quote:
Originally Posted by Badpuppy View Post
The "button" diodes (3 of them) are pressed into the deeper recesses of the aluminum rectifier heat sink in an alternator. A better choice for cutout mod is a stud mount type with heat sink compound for better heat transfer to the bus bar. Diode should be rated at least 25A. Use 12AWG for connection.

Example for negative ground -
https://www.ebay.com/itm/50-AMP-1000...-/121864495540

Positive ground type also available from the same seller.
Those would work also assuming they fit in the case. There is no reason you can't mount one remotely if you don't care about mimicking an original cutout.
Sparky is offline   Reply With Quote
Old 12-31-2020, 11:13 AM   #24
jwmckenzie
Senior Member
 
Join Date: Feb 2014
Location: Boston, MA
Posts: 131
Default Re: 12v from 3 brush Ford generator

Thanks to both of you. I am looking at increasing the wattage needed, looking at 20 amp peak @12 Volts. I know an alternator would likely make a better choice, but I want the look of the Generator. This thing won't see much use, not likely to see 5 hours on the engine over a years time.

Plus, anyone can put an alternator on. Due to the load, I ordered a 40 amp diode earlier from the source suggested instead of the one recommended by Sparky

Thanks again... Big help.
jwmckenzie is offline   Reply With Quote
Old 12-31-2020, 11:19 AM   #25
Pdgx
Member
 
Pdgx's Avatar
 
Join Date: Sep 2013
Location: Central Florida
Posts: 43
Default Re: 12v from 3 brush Ford generator

Quote:
Originally Posted by hop up View Post
Thank you Sparky Whats a fun projects regulator?
They won’t tell you if or when they will make one for you.

Last edited by Pdgx; 02-07-2021 at 03:58 PM.
Pdgx is offline   Reply With Quote
Old 12-31-2020, 04:48 PM   #26
Kurt in NJ
Senior Member
 
Kurt in NJ's Avatar
 
Join Date: May 2010
Location: on the Littlefield
Posts: 5,529
Default Re: 12v from 3 brush Ford generator

Sponsored Links (Register now to hide all advertisements)
They can't tell you if or when if the ic they use is not made anymore
Kurt in NJ is offline   Reply With Quote
Old 01-01-2021, 11:21 AM   #27
rotorwrench
Senior Member
 
rotorwrench's Avatar
 
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 12,761
Default Re: 12v from 3 brush Ford generator

It would be hard for them to help a customer if they can't make the product. Expecting a different outcome from folks when they can't come through is problematic. If someone can't help you it doesn't mean that they are unhelpful. They just can't help you.

This is a far cry from being dishonest so don't poo-poo folks unless their is a good reason to do so.
rotorwrench is offline   Reply With Quote
Old 01-03-2021, 10:27 AM   #28
hop up
Senior Member
 
hop up's Avatar
 
Join Date: Jun 2010
Posts: 410
Default Re: 12v from 3 brush Ford generator

Pdgx I never heard of the fun products and thought it would be more fun then a regulator:}
Thank you sparky for the information and plan to make one and put it into a original ford case like the fun products.
__________________
Wanted flathead speed equipment Thanks
hop up is offline   Reply With Quote
Old 01-03-2021, 10:45 AM   #29
jrelliott
Senior Member
 
jrelliott's Avatar
 
Join Date: May 2010
Location: Pine, AZ
Posts: 707
Default Re: 12v from 3 brush Ford generator

My only concern about the Fun Projects Voltage Regulator is that it regulates the output of the generator and not the generator field itself. You adjust the output of the 3rd brush to get 8 to 10 Amps then put on the regulator. Controlling the field strength which is essentially adjusting the 3rd brush is the best way to regulate the voltage out of the generator instead of converting to heat in the Fun projects regulator. The Fun Projects regulator does work very well. I am looking to find or design an electronic regulator that controls the field current. Tom Westberg has one for 6V, but not 12V. Finding electronic parts any more is difficult as there are no stores like the older Radio Shacks where you could find discrete components.
jrelliott is offline   Reply With Quote
Old 01-04-2021, 10:24 AM   #30
Badpuppy
Senior Member
 
Join Date: Dec 2017
Location: Guthrie, OK
Posts: 870
Default Re: 12v from 3 brush Ford generator

@jrelliott - You're right about the FP regulator. It is a shunt regulator, which means it simply dumps excess generator power to ground. I figure it wastes about 1 HP at the high end. 1 horse doesn't sound like much until you consider there are only 40 to start with (or you try to wrestle a horse).

The series regulation used in Tom Wesenberg's design is much more efficient. It simply interrupts field current when set voltage is exceeded, limiting the output.

Regulators for a model A aren't that hard to design, considering the requirements are quite simple. A few common parts are all that is required.

There are many parts suppliers online. Just google for any part and you'll find lots of sources.
Badpuppy is offline   Reply With Quote
Old 01-15-2021, 12:52 PM   #31
jwmckenzie
Senior Member
 
Join Date: Feb 2014
Location: Boston, MA
Posts: 131
Default Re: 12v from 3 brush Ford generator

Quote:
Originally Posted by Badpuppy View Post
The "button" diodes (3 of them) are pressed into the deeper recesses of the aluminum rectifier heat sink in an alternator. A better choice for cutout mod is a stud mount type with heat sink compound for better heat transfer to the bus bar. Diode should be rated at least 25A. Use 12AWG for connection.

Example for negative ground -
https://www.ebay.com/itm/50-AMP-1000...-/121864495540

Positive ground type also available from the same seller.
So I have received a 40amp diode, it's a stud mount, How much heat should I expect from this diode if we are running say 20 amps @12 volts.

Jon.
jwmckenzie is offline   Reply With Quote
Old 01-16-2021, 10:15 AM   #32
Badpuppy
Senior Member
 
Join Date: Dec 2017
Location: Guthrie, OK
Posts: 870
Default Re: 12v from 3 brush Ford generator

Quote:
Originally Posted by jwmckenzie View Post
So I have received a 40amp diode, it's a stud mount, How much heat should I expect from this diode if we are running say 20 amps @12 volts.

Jon.
Depends on forward voltage drop (Vf) of the particular diode. If you can't find the spec sheet, figure 1 volt drop: 1V x 20A = 20W. Grab onto a lit 20W bulb to find out how much heat sink is required. The copper bus inside an original cutout should suffice. Just be sure the arrow on the diode points toward the negative side.
Badpuppy is offline   Reply With Quote
Old 01-16-2021, 01:56 PM   #33
jwmckenzie
Senior Member
 
Join Date: Feb 2014
Location: Boston, MA
Posts: 131
Default Re: 12v from 3 brush Ford generator

Thank you....
jwmckenzie is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 09:27 AM.