Paper-ing my Stator: Or... Electricity confuses me

[Killer2600]

Sorry I posted in a hurry and got wrapped up in Eil's degenerate cases. See if you can find it.

You'll have to clarify what "it" is, I already found waldo

[Matchless]

Hi Roostabunny,
Without the bike running and the 3 stator leads disconnected, do a quick resistance test between the 3 AC wires and the casing. There should be no continuity at all.

Its usually a good idea to do a resistance check on any stator before installation.

I find that this test is often overlooked.

A copper wire wound recklessly wound can make through on a sharp edge and cause this.

[Roostabunny]

Hi Roostabunny,
Without the bike running and the 3 stator leads disconnected, do a quick resistance test between the 3 AC wires and the casing. There should be no continuity at all.

That's part of the puzzle, man. It's buried back there on page 6, but with the bike off and stator leads disconnected I got 1ohm between legs and infinite resistance from leg to ground.

Edit: Not that I'm dismissing the possibility of a workmanship problem with this stator.

[Matchless]

That's part of the puzzle, man. It's buried back there on page 6, but with the bike off and stator leads disconnected I got 1ohm between legs and infinite resistance from leg to ground.

Edit: Not that I'm dismissing the possibility of a workmanship problem with this stator.

Sorry missed that. I usually do that test with a 1000V Megger, if the multimeter shows nothing, which is an old insulation tester with a crank handle I have. Maybe its just happening when hot or breaking down at higher voltage only.

[posplayr]

Sorry missed that. I usually do that test with a 1000V Megger, if the multimeter shows nothing, which is an old insulation tester with a crank handle I have. Maybe its just happening when hot or breaking down at higher voltage only.

There is quite a difference between an 3V ohmmeter and a 1000V Megger

[Matchless]

There is quite a difference between an 3V ohmmeter and a 1000V Megger

Jim, I must say you are right, they don't look alike at all and quite a substantial price difference! My Megger is a 1960 model and still going strong.

[posplayr]

Jim, I must say you are right, they don't look alike at all and quite a substantial price difference! My Megger is a 1960 model and still going strong.

I just discovered that there are several available for very reasonable prices on Ebay.

Old school:
Silver Tone Resistance Measurement Tester Megger

http://www.ebay.com/itm/Silver-Tone-Resistance-Measurement-Tester-Megger-Megohmmeter-/321063607409?pt=LH_DefaultDomain_0&hash=item4ac0e1dc71

Digital :
VC60B+ Digital Insulation Resistance Tester Megger

http://www.ebay.com/itm/VC60B-Digital-Insulation-Resistance-Tester-Megger-MegOhm-Meter-USA-Seller/320898816590?rt=nc&_trksid=p2047675.m1851&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D163%26meid%3D8932750316131304155%26pid%3D100005%26prg%3D1088%26rk%3D2%26sd%3D321063607409%26

[Roostabunny]

Sorry missed that. I usually do that test with a 1000V Megger, if the multimeter shows nothing, which is an old insulation tester with a crank handle I have. Maybe its just happening when hot or breaking down at higher voltage only.

No worries - this thread has really ranged.

And yes, I was going to say, that sounds similar to what Posplayr's said about getting AC voltage to ground (when we know the stator's putting out 80V) despite clean leg-->ground results from a 9V meter continuity test. 80VAC (or 1000V) is a lot more potential pushing on that insulation - if I haven't murdered the electrical metaphor.

Makes me wonder - my apparent ignorance about electricity belies the fact that I work for a telecom equipment manufacturer. I'm sure I've heard of a megger, and now I'm wondering if there's one in the building I could carry down to the parking lot. I'll ask around.

[Guest]

We used to have plenty of Meggers aboard when I was in the Navy, but if you check the prices on them you will see why you don't ever see them very much. They are the only reliable way to check insulation varnished wire. It's must have test equipment if you do a lot of motor or stator winding, but most people just buy replacements instead of fixing stuff anymore.

[posplayr]

We used to have plenty of Meggers aboard when I was in the Navy, but if you check the prices on them you will see why you don't ever see them very much. They are the only reliable way to check insulation varnished wire. It's must have test equipment if you do a lot of motor or stator winding, but most people just buy replacements instead of fixing stuff anymore.

You apparently missed my post RE ebay meggers above.

[Guest]

No, the Silver-Tone looked interesting, but where would you get one calibrated? I don't think I would trust a $50.00 electronic megger, kind of like a $2.00 multimeter, but I would be delighted to be proved wrong.

[posplayr]

It can happen

http://www.thegsresources.com/_forum/showpost.php?p=1895734&postcount=9

[posplayr]

No, the Silver-Tone looked interesting, but where would you get one calibrated? I don't think I would trust a $50.00 electronic megger, kind of like a $2.00 multimeter, but I would be delighted to be proved wrong.

Well who really needs to have it calibrated? If it will produce 250V your volt meter can probably measure that to confirm, you have a pretty good stress test for your stator. Detecting shorts is all you are really doing, you are either pregnant or not.

[Matchless]

How about that! The silver one with the handle looks the same as mine. Except mine is marked as made in Britain for the Union of South Africa which was before 1961.
Just a correction mine is 500V, not 1000V, I was confusing it with a different one we used to do open line testing for LI and that was many years ago!
Well had smaller ones that used 100V and 250V out as well.

Apologies for messing up your thread Roostabunny.

I just discovered that there are several available for very reasonable prices on Ebay.

Old school:
Silver Tone Resistance Measurement Tester Megger

http://www.ebay.com/itm/Silver-Tone-Resistance-Measurement-Tester-Megger-Megohmmeter-/321063607409?pt=LH_DefaultDomain_0&hash=item4ac0e1dc71

Digital :
VC60B+ Digital Insulation Resistance Tester Megger
http://www.ebay.com/itm/VC60B-Digita...21063607409%26

[Roostabunny]

OK, two updates.

First off, I spoke with Rick at Rick's Motorsports Electrics and he indicated that you'll normally see about half the output voltage when you test from leg-->ground with the bike running. Hmmm.

This doesn't at all explain the dropping battery charging voltage with increased RPM, but he made a couple of sensible suggestions:

- making sure all three legs connected directly to the R/R (I think mine do, but need to double check - might have the loop to the ignition switch that Rick mentioned)

- use an inline fuse to bypass the harness and connect the positive R/R output to the + terminal on the battery (which I think Posplayr already mentioned in this thread, and which I already have a fuse holder for)

The second thing is that I opened the box my new regulator shipped in and pulled out... a tiny SPACESHIP! Ok seriously though, it's not what I expected, so I'll post pics in a bit. It's probably the right thing and I just need to search on here to find out how to connect it.

EDIT: OK some quick searching confirmed what I suspected, that the unit I bought is the correct unit and that connecting it takes additional parts/ingenuity. I kept the pic post anyway, for reference.