The Stovebolt Site Forums The Shop Area The Electrical Bay Wregulator wrestling

I have been at odds with my regulator for many years. Recently - after a lot of detailed instruction from Jerry - it has been behaving fairly well. I have adjusted all the voltages pretty close to specs, but still when I have been running with lights the cutout relay has not been releasing if I shut off the motor immediately after shutting down the lights.
So 2 days ago I adjusted everything yet again, and again it was working just great until I turned the lights on. So just for giggles, I checked all those voltages with the lights going. Shouldn't a regulator in good trim give the same readings with or without lights? As long as the gen is producing enough? Anyway, in reality those carefully adjusted voltages were all over the map. What really goosed me was that the output voltage from the generator (measured at the middle post on the reg) could be as high as 8 but the bat voltage was well under the 7.3 volts that I measured without the lights.
What I could also see was that the single-contact cutout relay on my newer regulator gets pretty warm when the lights are on.
So I says to myself, why not clean up the old reg, readjust according to the shop manual including the air gaps, and drop it back in again? And so I did. Among other things I noticed that the older model had a double relay on the cutout relay, which tells me that it won't heat up so much. The short version is that after a good bit of tweaking the old regulator is back in place and feeling fine.
My greatest concern is that I do not have a good enough ammeter to adjust the current relay. I have been setting the voltages well enough, and then playing with the current relay so that it shows a slight charge at the dashboard even with the lights on. The problem is that without the lights the dashboard "ammeter" shows a strong charge. I should think that when the current relay is adjusted to work properly without the lights it should not change with the lights on, provided the rpms allow the gen to produce.
FYI 7 years ago I replaced the regulator after leaving both the reg and the gen to the local auto-electric shop. I suspect they checked the generator, saw it was good, and concluded that the reg must be the problem, and told me to replace it.
If there is a question here, I suppose it is whether the voltage (and current) settings after the regulator shouldn't be the same with or without the lights burning.
Karl

You shouldn't see a change in charging current on the ammeter when the lights are switched on and off. It sounds like the current regulation is not working.

The only purpose for a current regulator is to prevent the generator from overloading itself when charging a VERY low battery. Once the output of the generator drops below 30-35 amps, depending on which generator you have, the current regulator should not be operating at all. It's in series with the voltage regulator points, so it's an either/or situation- - - -voltage and current regulation DOES NOT work at the same time. It might be possible to turn on enough accessories such as electric wipers, high beam headlights, high speed heater fan, and maybe a cigarette lighter (all at once) to use up the full output of the generator, but that's the only situation I can imagine where the current regulator would be operating other than when recharging the battery immediately after a long cranking session with the starter. If you've got a major difference between the armature voltage and the voltage present at the battery posts, you've got some dirty connections somewhere between the regulator and the battery, or maybe some burned cutout relay points. Heat indicates resistance, so if the cutout is getting hot, that's your voltage drop point. Clean 'em up or go back to the original-equipment type regulator.
Jerry

I've got the original regulator back in place now. Like I wrote, I had noticed that it has two contact points on the cutout relay instead of only one on the newer model. If all the current must pass through the cutout - lights included - then that single contact point on the cutout might get a little warm, don't you think?
In any event, with either of the regulators in place the ammeter on the dashboard shows a very different activity depending on whether the lights ar on or not.
Do you mean to say that in normal usage the current relay should be made, and that the contacts are only broken at higher gen output? I should expect more activity on the voltage relay than the current relay? What in the heck is the dashboard ammeter actually measuring?
Karl

The ammeter is measuring the current that's going in or out of the battery. All of the electrical load, ignition, lights, and accessories, is being tapped off downstream of the ammeter if the system is wired correctly. Let's compare the charging system to a water system, with a reserve tank, a well pump, and various demands such as a garden hose, household taps in the kitchen, bathroom, etc., and a sprinkler system to water the yard. As long as the pump is able to produce more water than the system demands, some of it can be used to fill the reserve tank. With no demand, a pressure switch (the voltage regulator) will shut the pump off when the desired pressure level is reached to avoid damaging the pipes from overpressure. As water taps are turned on, the pump will supply the damand, and the remaining volume is used to keep the tank full. In the event more water is demanded than the pump can supply, the reservoir tank makes up the difference, at least until it empties itself.

The volume of water going into the tank (amps) will change according to how much demand is being made on the pump by the system taps because the pump has a limited capacity (controlled by the current regulator, for instance). In the electrical system, generator (or alternator) output is used to supply the system demands first, and whatever excess current capacity that's available, if any, is used for battery charging. The ammeter is wired to show how much current is going into, or out of the battery only- - - -it does not show how much demand is being made by the system unless the engine is not running and/or the generator is not charging for some reason. Yes, the vast majority of the time, the system control is done by the voltage regulator only- - - -the current regulator only functions during periods of extreme demand to prevent overloading of the generator. An alternator stator is self-limiting due to the resistance of its windings, but a generator armature can destroy itself from overcurrent unless its output is controlled by the current regulator.

Are you confused yet?
Jerry

Confused, me? I have a primitive appreciation for the theory, but it hasn't always helped me in the practical application. I'll keep tweaking as best I can according to this long distance tutorial. Sooner or later I'll get it by accident.
Karl