Re: Voltage regulator
 

Thanks for your hard work it's nice to have these available again!

Re: Voltage regulator
 

Very excited for this new regulator. I have had the fun projects regulator for a number of years and have sorely missed it ever since I accidentally shorted it out. Looking forward to being able to try out the new unit!

Re: Voltage regulator
 

I'd like to hear more details on your regulator!

Thanks steve

Re: Voltage regulator
 

What do you want to know??? Lots of background info here:

https://modeltstarters.com/voltage-regulators-cutouts/

Re: Voltage regulator
 

Good info, thanks. How does it does it control field strength? Is the 3rd brush removed and it's field wire routed to the regulator? I didn't see any photos of it mounted on a generator and details of how its connected.

I rebuild model A and flathead V8 generators on the side, so I have interest in the details. It certainly is a great idea. This is an example of one I recently finished.
Thanks., Steve

Re: Voltage regulator
 

Jazzmonger,
Please keep us posted. I’ll be in the market for 2 6V positive ground units.
Thanks - Jim

Re: Voltage regulator
 

It's literally a bolt-on replacement for standard Ford cutouts. No other mods necessary...

Re: Voltage regulator
 

Ok, thanks.

Re: Voltage regulator
 

Okay, just out of interest and keep in mind that i am not an electronics engineer...


As i understand it, you have two ways to regulate the voltage if you are not regulating the field strength.


- 'burn off' the surplus electrical energy, as done in voltage regulators like a LM7805 or similar. You need a heatsink for this and as you may have to get rid off 60 or more watts, i don't think this the best way...


- switch the current coming from the generator on-off at a high frequency, (like PWM-controlled) and with this you can regulate the outgoing voltage. To get rid of the 'ripple' in the output current, you put in a condenser. (plus the battery, which is working as a huge condenser)


I am just curious and trying to understand things...

Re: Voltage regulator
 

Do you put the third brush in the maximum position?

Re: Voltage regulator
 

Adjust the third brush to 14 or 15 amps. That's all you have to do.
I have the fun projects regulator and it works fine.

Re: Voltage regulator
 

You describe a series regulator such as used in the internal Wesenberg type, which switches field current to limit output voltage. Regan's external shunt (parallel) regulator pulses excess power to ground using a PWM controller.

As for ripple, the system tolerates the large ignition spikes from the coil, which are easily absorbed by the battery; ripple caused by regulator switching is hardly a problem.

Re: Voltage regulator
 

In fact, my strong recommendation is to set the gen to approx 5A, or 2-3A with the standard (not LED) lights on. These generators were designed for 100watts MAXIMUM, and that's assuming everything is perfect. Run them at more than 50w and you reduce their useful life drastically. My business is also rebuilding Model T generators. I've rebuilt 100's over the years and I have just a bit of experience I can impart in this area:

P=VI (or Power in watts = Volts * Current)
100w=6v* 16.7A - @100% rated output.
50w=6v*8.3A @ 50% rated output.
5A * 6v = 30 watts. Keeps thing nice and cool and long lived! Longer anyway....but, as always, your mileage will vary greatly! 5A is enough to keep a 6v battery in good condition charged in the vast majority of cases.

In practice (not theory) we found drawbacks to using the pwm design, so we took a different approach. The new circuit acts like a switch. When the battery is at 6.2v or below, the switch on the gen terminal is open, letting current flow to the battery. Once the battery voltage reaches 7.2v (100% charge) the switch closes and shorts the generator output to ground, effectively stopping current flow to the battery. The cycle then repeats. One of the biggest complaints about the pwm design from the avg user is it was hard to tell if it's working, esp when the battery was near full. This new design is obvious. Your ammeter is either showing a charge or not. This is especially helpful when driving these old cars because for us old guys, the more time spent watching the road and not interpreting the value on a small gauge, the better it is for everyone... ;)

Jeff

Re: Voltage regulator
 

6V is used in those calcs, I’ve always read that the system runs more at 7.2V or so. Does that affect the maximum amps you want to see?

Re: Voltage regulator
 

The ammeter is a battery charge indicator. It doesn't tell you much about the generator except that it's working. 1-2 amps is a good steady charge for a healthy battery, after recovery from the starting discharge.

I would say the best way to adjust the third brush is to run the engine to engage the cutout or diode, ~1200 rpm, and set to 6.8 - 7.0 volts between battery terminals. The regulator of course will prevent output above 7.2V, at perhaps 1300-1500 rpm.

Re: Voltage regulator
 

[6V is used in those calcs, I’ve always read that the system runs more at 7.2V or so. Does that affect the maximum amps you want to see?]

Yes it does! When the battery is fully charged, 7.2 *5A = 36w. Still safe!

I'm happy to post my instructions for setting the 3rd brush here.

Jeff