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

[Roostabunny]

Pics of the new spaceship.

 

[Steve]

- 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)

Not sure if Rick realizes this or not, but there is no "loop to the ignition switch". :-k

However, there is a loop that used to go to the headlight switch. On newer bikes, it stops part-way there and loops back under the tank or in the headlight bucket, depending on your bike model.

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[posplayr]

If that measurement is normal then the neutral must be grounded to the case. Does he also claim the the ohm meter will show an open between legs and ground? These two outcomes are in compatiable.

 

[Roostabunny]

Not sure if Rick realizes this or not, but there is no "loop to the ignition switch". :-k

However, there is a loop that used to go to the headlight switch. On newer bikes, it stops part-way there and loops back under the tank or in the headlight bucket, depending on your bike model.

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I was talking from memory, and I've been reading a lot of electrical posts and not getting enough sleep. "loop" is the only thing I should definitely attribute to Rick on this one. He might have said 'headlight switch' or even 'up toward the front of the bike'.

 

[Steve]

If that measurement is normal then the neutral must be grounded to the case. Does he also claim the the ohm meter will show an open between legs and ground? These two outcomes are in compatiable.

If I remember my meager training with 3-phase circuits correctly, that would be the difference between a "delta" and a "wye" setup.

Either one will work, but the tests will be different.

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[Roostabunny]

If that measurement is normal then the neutral must be grounded to the case. Does he also claim the the ohm meter will show an open between legs and ground? These two outcomes are in compatiable.

Pretty sure he did. He made a point to ask about infinite resistance when the bike was off and reacted as if that were the definitive "thumbs up".

 

[Matchless]

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.

Some serious misunderstanding here I think. This is impossible if the stator wires are not connected to the R/R. The ground (frame) is not part of the circuit it should be insulated from the windings!

 

[posplayr]

Some serious misunderstanding here I think. This is impossible if the stator wires are not connected to the R/R. The ground (frame) is not part of the circuit it should be insulated from the windings!

ironically the only way that I can think to explain Roostabunny's measurements is if the stator is wound as a Why ("Y") and has the neutral grounded or at least appears to be a ground at 80 VAC.

Mow, back to electricity...


I didn't get quite the readings I expected

Passive resistance
Leg-->Leg PASS
1
1
1

Leg-->ground PASS
L
L
L

VAC at 5K RPM

Leg-->Leg PASS
80
80
80

Leg-->ground What the?
40
40
40


Gotta head out with the fam for a couple of hours - lemme know what you think when you have a chance - thanks!
__________________
Roostabunny

 

[Matchless]

I wonder if the passive resistance test still shows infinity between ground and any of the legs? Usually the passive test shows these type of faults 9/10 times and the rest are intermittent when hot etc.

Yes, Jim you are right and my age is catching up with me! The ground is floating when the R/R is disconnected and the "contact" with the windings will act as a sort of takeoff point or tap and part of the windings will then be measured which could give the 40V AC or any voltage up to 80V dependent on how much of the windings are between the wire and ground. Between ground and the other legs one would expect a relatively higher or lower voltage again depending on where this contact is. Getting exactly 40V AC on all three legs may indicate that the contact is slap bang in the center of the windings and the center is where the 3 phases are joined. Maybe the sleeving has moved there?

 

[Roostabunny]

I wonder if the passive resistance test still shows infinity between ground and any of the legs? Usually the passive test shows these type of faults 9/10 times and the rest are intermittent when hot etc.

Yes, Jim you are right and my age is catching up with me! The ground is floating when the R/R is disconnected and the "contact" with the windings will act as a sort of takeoff point or tap and part of the windings will then be measured which could give the 40V AC or any voltage up to 80V dependent on how much of the windings are between the wire and ground. Between ground and the other legs one would expect a relatively higher or lower voltage again depending on where this contact is. Getting exactly 40V AC on all three legs may indicate that the contact is slap bang in the center of the windings and the center is where the 3 phases are joined. Maybe the sleeving has moved there?

Well, I've got some prep to do before I'm ready to mount this SH775, but before I tear into that I'll take the measurements one more time.

The the plan's to install the SH775 and also install a fused run directly the R/R to the + terminal.

BTW, do you guys still have that rubber boot that houses the charging system connectors - behind the airbox there? It serves its purpose, but it bugs me and I have a hard time getting it out of the way, just curious about alternatives.

And as an aside, she's definitely charging. Fires right up, no hesitation and I haven't put the battery on a charger all week.

 

[tom203]

ironically the only way that I can think to explain Roostabunny's measurements is if the stator is wound as a Why ("Y") and has the neutral grounded or at least appears to be a ground at 80 VAC.

I've openned up two suzuki stators- both Y wound with center connection clearly isolated from ground. You could wind stators delta connected but you would have less voltage at low rpm when most of us need it.

 

[tom203]

Well, I've got some prep to do before I'm ready to mount this SH775, but before I tear into that I'll take the measurements one more time.

The the plan's to install the SH775 and also install a fused run directly the R/R to the + terminal.

Use a 25 amp fuse minimum (and carry a spare!)

 

[Roostabunny]

Use a 25 amp fuse minimum (and carry a spare!)

Reading around I had figured on a 30 amp. Too much? But yes, spare fuses are a must.

Course, Tom, didn't I pick up on one of these threads that you have a spare R/R installed on your bike? I'd that makes you a serious advocate for preparedness.

Edit: Oh, duh, you said 25 minimum, so 30A is right on. Never mind.

 

[posplayr]

Reading around I had figured on a 30 amp. Too much? But yes, spare fuses are a must.

Course, Tom, didn't I pick up on one of these threads that you have a spare R/R installed on your bike? I'd that makes you a serious advocate for preparedness.

Edit: Oh, duh, you said 25 minimum, so 30A is right on. Never mind.

If you wire the R/R using the fuse box (stock location for the R/R(+) ) then you should be able to get away with a 15 Amp main fuse.

I don't think using a 25-30 amps fuse is a good thing, you could easily melt insulation and plastic before that ever blows.

 

[posplayr]

I've openned up two suzuki stators- both Y wound with center connection clearly isolated from ground. You could wind stators delta connected but you would have less voltage at low rpm when most of us need it.

Yes, most seems to be wound "Wye", but some manufactures have gone to a delta; I just dont recall which at the moment.

 

[tom203]

If you wire the R/R using the fuse box (stock location for the R/R(+) ) then you should be able to get away with a 15 Amp main fuse.

I don't think using a 25-30 amps fuse is a good thing, you could easily melt insulation and plastic before that ever blows.

If he is wiring R/R positive output direct to battery, he needs about 20 amp fuse for a little safety margin . I split my R/R output positive output- a 20 amp fused line direct to battery and other into harness; this way most of R/R output goes into harness and "bypasses" the battery. But if my harness wiring someday develops problems, I have the 20 amp as a backup.
I agree that 30 amp is oversized , but depending on his loads, a 20 amp could blow at an inconvenient time. I'd start with 20 amp and carry spares.

 

[posplayr]

If he is wiring R/R positive output direct to battery, he needs about 20 amp fuse for a little safety margin . I split my R/R output positive output- a 20 amp fused line direct to battery and other into harness; this way most of R/R output goes into harness and "bypasses" the battery. But if my harness wiring someday develops problems, I have the 20 amp as a backup.
I agree that 30 amp is oversized , but depending on his loads, a 20 amp could blow at an inconvenient time. I'd start with 20 amp and carry spares.

I' m pretty sure you don't want two paths even if they are both fused. If they were to share current equally you would be capable of drawing twice the lower amperage of the two fuses. How current sharing might occur is very speculative without details but it there is evidently some as that is what you claim is the purpose. This is DVD. Worse than having a single 30 amp fuse. What happens if an scr shorts in an r/r? How much current gets to that short before one of the fuses blows?

 

[tom203]

I ran this two path setup with my shunt R/R ; I'll ponder your thoughts, but I initially think it's more likely that one of my feeds would chafe against frame and ground out-resulting in blown fuse on either or both feeds- than a SCR frying in the "on" state like a zener diode. My hunch is that Shindengen has anticipated this problem (in the SH775) and has some built in current limiter in for a disaster scenario.