Stator Paper R/R test. Test regulator?

[Redman]

THe stator paper part C, is for doing the R/R checks with a meter. It specifiys using the diode check feature of a meter. (Zuzuki manaul specifys Ohm checks, but that was early 80s, meters now more likley to have diode checks).

The stator paper has me check from r/r output (red) to each of the 3 phases (in both polaritys of the meter), and then has me check from r/r ground (blk/wht) to each 3 of the phases (again in both polarity of the meter).
I can understand that is using the "diode check" feature of the meter to check the diodes.
ANd I understand what the "diode check" function of the meter is. And I understand what the diodes in the R/R are and what they are doing (3 phase, full wave rectification). And I understand that we are checking the diodes (the rectification part of the R/R) and not checking the regulator portion of the R/R. Then the stator papers then say "that is all, if checks out okay, then only thing left is the battery". But...but...but.. have only checked the the rectifier portion of the rectifyer/regulator.

What I am questioning is this:
Why dont we do any checks from the r/r output (red) to the r/r ground in an attempt to check out at least something of the regulator part of the R/R?

I suspect this schematic of the R/R internals might be somewhat simplified, but using it anyway.....

Looks like if test from output (red) to ground (b/w) that would go thru the one diode and then thru the regulator portion. BUt the regulator portion presents a couple parrallell-series-parrallel branch paths, but still seem to me that a good r/r whould exhibit certain characteristic, and a r/r that had some problem with the regulator portion, like shorted out SCR or blown open ZE or something (dont know what a common problem would be) would exhibit other characteristics.
Oaky, I will admit that I have only a basic understanding of electronics, and little experince or practical knowlodge.
Maybe someone can say, that "NO! there is no way to do any static tests with a meter" on the regulator portion of the R/R.
But the stator papers make it sound like that the test they specify have been a total and complete test of the R/R.

I do see that when checking from ground to yellow that are would be checking that one doide and that the regulator (ZE & SCR) are in parrallell with that doide. SO maybe that is the answer, if regulator part were to be shorted (zero ohms) then would not pass that diode test. BUt if ZE or SCR were blown open the diode test would still pass, ... so again, why dont we test anything from output to ground?

So I am asking, why dont we ... . . . ...... ?
And Then I do it anyway.

My check of my R/R (2 year old Ricks) using the diode check feature of a nice Fluke is:
-Black meter lead to R/R output (red)
and meter red to each r/r phase reads .55, .55, .56 volts
and meter red to r/r ground reads .75 volts
- Then Red meter lead to R/R output (red)
and meter black to each r/r phase reads 2.55 (open) on all
and black red to r/r ground reads 2.55 (open)

And ask if there is any significance there or not?

Maybe someone with a known good R/R can do the checks acraost the red to b/w.

.

 

[Steve]

Not sure of the significance of your readings, but I am under the impression that to check the Zener and the SCR, you would need access to the center of the diodes. Since it appears that the yellow input to the r/r is connected to the SCR as well, you might be able to check that with a variable power supply. I don't happen to have one on my bench, so try it an let us know how it turns out.

.

 

[Redman]

Steve, I would be lacking more than a variable power supply to do that. And thanks to your previous PMs I did gather a better understanding of a few things.

Where I sit at present with all this is this:
- I can see I have good 3 phase AC going into the R/R, and the diodes in the rectifyer test good with didoe check of meter. And I see the voltage output (r/r red to r/r ground wire) is like 12.5 to 12.9, maybe 13.0 sometimes. So I would say that is a "functional test" that shows the regulator portion is bad. It got the right stuff going in, but not the right stuff comming out, so .....
- Here I sit waiting for a Duaneage R/R kit. Maybe if I stand at end of droiveway and hollar "Come on, big brown truck." ,it might come sooner.
- and here I sit, pondering the vast unknowns of the universe such as the inner workings of a R/R regulator and how the stator papers talks so definitly about testing the R/R. And the R/R passes all the stator paper test. But seems to me can only really check only part of of it, not all of it,..... and it appears to me the the R/R isnt functioning properly.
- Geepers, Wally. This is almost a phylosophicall delema, maybe should be in off-topic. The Stator Papers say this right here, and I think that means this-and-that-and-that, so that is all there is too it. But yet if I understand this other subject/situation over here, then I can conclude something else. Ahhhhhhhh

 

[duaneage]

It left already, I swear! Remember a watched mailbox never fills. I did four that night and then had to do two more today, including a custom wire length jobbie.
In between all this I'm trying to paint my bedroom, and it's become a real project to say the least.

 

[Steve]

It left already, I swear! ... I did four that night and then had to do two more today, ...

Good, that means that mine is on the way, too. \\/

.

 

[Redman]

Remember a watched mailbox never fills. .

Duane,
Oh, "mail box"...
So it is the white red and blue trucks that I need watch for, not the brown trucks.
Thanks Again for the prompt service on this order and for your service in general. THanks again for the instructions, Dave

Anybody,
Anybody have any comments about R/R testing ?
Stator papers seem to say that is a complete test, but I question how complete of a test it is.

 

[tomm]

My two cents - not possible to check regulator portion of R&R with just a meter other than the voltage measurements already outlined in the stator papers. The rectifier diodes get in the way of any resistive or bias measurements across the rectifier circuit if everything is good, and if something measures bad, it doesn't matter whether if it is the rectifier diodes or the regulator circuit . . . it's still bad.

My check of my R/R (2 year old Ricks) using the diode check feature of a nice Fluke is:
-Black meter lead to R/R output (red)
and meter red to each r/r phase reads .55, .55, .56 volts
and meter red to r/r ground reads .75 volts (These are the voltages that the rectifier diodes forward bias at, either singly or in series. At least you know there isn't a dead short across the regulator, but not if it is working or open. And your individual diode checks, either resistive or bias, already confirmed the diodes were good.)
- Then Red meter lead to R/R output (red)
and meter black to each r/r phase reads 2.55 (open) on all
and black red to r/r ground reads 2.55 (open) (Rectifer diodes, reverse biased. Again, all you know is that their isn't a dead short across the regulator.)

Stator papers includes a regulator check right at the beginning where you check the battery voltage. If just the regulator is dead, your voltage will be too high. If it's too low, could be a number of things, but process of elimination may point to the regulator if everything else is good.

You indicated your battery voltage was around 12.8 - 13, so the regulator must be bad. Assume you're thinking that it should be a little higher when engine running at high RPM with minimal load. I suppose it is possible that the zener might be conducting a little early and triggering the SCR, but personally, I would suspect a bad ground somewhere. However, if you put an analog meter on the battery and increase the RPM's, you should be able to see exactly where the regulator cuts in. It should show the voltage increasing as you increase the RPM's, then suddenly drop back just a bit and stay there. If that is what you are seeing around 13 volts, then at least it shows that the regulator circuitry is working. As for why it is triggering a little early, could be the regulator, but could also be bad connections, sense wire (if you have one) connected to the wrong place, or a bad ground. Connections more likely based on the way the zeners and SCR's usually fail, but not out of the question that regulator is bad. If it doesn't look like the regulator is actually cutting in, then low output is probably another problem. Bottom line, testing the regulator is done by testing the battery voltage at various engine speeds and then process of elimination of everything else.