Dead Stator...RM Stator

[posplayr]

How do you know that blue stuff is power coat? And if it is, how do you know it cures at 400F? There are various grades and types of powder.

Because it takes over 500 degrees to make $hit burn

And our resident expert on stator rewindings suggested that is what it is (Matchless)

Ed, I think you will find in YOUR research that thermal epoxies cure right in this temperature range.


I think I hear quacking and something waddling around .................wonder what it might be

 

[bluewool]

I was using 300F(150C) because it's the low side of internal temperatures for alternators/motors. No specifics on the particular GS winding.
If yours are running 400-500F that's a ton of extra heat!! That's much hotter than I would have expected any sane person to design!! have you ever checked the temperature of the side case after a long fast run? it would be interesting. I will try to at some point.

 

[posplayr]

I was using 300F(150C) because it's the low side of internal temperatures for alternators/motors. No specifics on the particular GS winding.
If yours are running 400-500F that's a ton of extra heat!! That's much hotter than I would have expected any sane person to design!! have you ever checked the temperature of the side case after a long fast run? it would be interesting. I will try to at some point.

with the hand at least it is very hot using SHUNT R/R.

I think the power disappation requirements for the stators are: "out of sight out of mind."

 

[tom203]

with the hand at least it is very hot using SHUNT R/R.

I think the power disappation requirements for the stators are: "out of sight out of mind."

When my stator failed (short to ground ), out of curiosity the next day I started it up. Within 1 minute the stator cover was VERY hot as the short circuited windings had their fun.
I'm still absorbing the Compufire info, but my initial impression is that it was originally designed to boost output at low rpm on behemoths , but it's ability to open circuit stator output seems interesting. But when all is said and done, the stator has to pump out 150 (?) watts just to keep up with power needs.

 

[posplayr]

I was using 300F(150C) because it's the low side of internal temperatures for alternators/motors. No specifics on the particular GS winding.
If yours are running 400-500F that's a ton of extra heat!! That's much hotter than I would have expected any sane person to design!! have you ever checked the temperature of the side case after a long fast run? it would be interesting. I will try to at some point.

It just occured to me that at some point while I still had the FET R/R installed I held a thermocouple a different spots on the engine*just by han d so not very accurate). It may have been after a ride or after doing those current measurments but the stator cover was at least as hot as the head measured near the combustion chambers.

 

[posplayr]

When my stator failed (short to ground ), out of curiosity the next day I started it up. Within 1 minute the stator cover was VERY hot as the short circuited windings had their fun.
I'm still absorbing the Compufire info, but my initial impression is that it was originally designed to boost output at low rpm on behemoths , but it's ability to open circuit stator output seems interesting. But when all is said and done, the stator has to pump out 150 (?) watts just to keep up with power needs.

without knowing where it shorted hard to conclude much but say voltage has dropped. Short to ground short to winding??

The need to get high current/voltage at low RPM drove the design to become more efficent that is correct.

I dont really understand your last statement. I provided a simplified explaination of the SERIES v.s. SHUNT operations which show the current and stator power disappation of both.

http://www.posplayr.100megsfree3.com/FH012AA_Charging/RR_Tutorial.pdf

when using a SHUNT R/R the stator has to carry almost twice as much current as when running the SERIES R/R

 

[tom203]

My dead stator still showed .9 ohm between any two phases.I cut the wye connection and found that two phases were shorted to ground. I measured wire size at .040 inch- probably 20 gauge figuring something for insulation.
As for Compufire, I did ponder your link, but I think it's a little misleading.When the series r/r is in regulating phase, I think it is switching stator current flow on/off mucho times a second to limit effective maximum current- if it just open circuited it, there would be no power from stator. This is a good idea as you don't need 25 amps running thru it as could happen with shunt r/r dump.
The problem seems to be that to get decent output at low rpm, you have too much at high rpm. The Compufire idea makes sense.

 

[posplayr]

As for Compufire, I did ponder your link, but I think it's a little misleading.When the series r/r is in regulating phase, I think it is switching stator current flow on/off mucho times a second to limit effective maximum current- if it just open circuited it, there would be no power from stator. .

sorry to mislead with providing cycle by cycle voltage and current waveforms

 

[Darkstang]

Ok, back from a weekend of camping and doing NOTHING...

WHERE can I get one of those fancy compufire r/r? I can find the 32 amp one but not the 40. Dennis Kirk is out of stock.

On the heat issue, I will take pic with my thermal camera when I get it running... my job is running Vibration Analysis and Thermal Imaging routes and an Alltrade Mechanic for a large paper plant.

I have an associate degree in electronics and one of the pet projects i designed years ago with my old boss for our personal use was a circuit to run axuillary lighting for our 4x4's that ran the lights off a 12vdc square wave. We could run about a 75% duty cycle before the light out put got dimmer. Fillament would cool down any shorter.

I got out of the surface mount and Electronics Design aspect a long time ago. I am more at home with large AC and DC drives, motors and PLC's.


Ken

 

[tom203]

sorry to mislead with providing cycle by cycle voltage and current waveforms

Golly, those diagrams and graphs are sure pretty, and show that it works but how about the hows and whys? I hope it's not magic , cuz my faith in science is already strained.

 

[posplayr]

Golly, those diagrams and graphs are sure pretty, and show that it works but how about the hows and whys? I hope it's not magic , cuz my faith in science is already strained.

I'm sure I don't have the patience for what you need

 

[tom203]

I'm sure I don't have the patience for what you need

Sounds reasonable to me.

 

[posplayr]

Word......................

 

[posplayr]

Ok, back from a weekend of camping and doing NOTHING...

WHERE can I get one of those fancy compufire r/r? I can find the 32 amp one but not the 40. Dennis Kirk is out of stock.

On the heat issue, I will take pic with my thermal camera when I get it running... my job is running Vibration Analysis and Thermal Imaging routes and an Alltrade Mechanic for a large paper plant.

I have an associate degree in electronics and one of the pet projects i designed years ago with my old boss for our personal use was a circuit to run axuillary lighting for our 4x4's that ran the lights off a 12vdc square wave. We could run about a 75% duty cycle before the light out put got dimmer. Fillament would cool down any shorter.

I got out of the surface mount and Electronics Design aspect a long time ago. I am more at home with large AC and DC drives, motors and PLC's.


Ken

The 32 amp is not 3 phase. Use the part number I provided.

 

[Darkstang]

Ok, a new stator is on it's way. I found the 40 amp 3 phase part number listed at K&G cycles, USMOTOMAN, Dennis kirk (out of stock).

Anywhere else I have missed to price shop?

Be busy this weekend installing new tires and new stator.

 

[posplayr]

Ok, a new stator is on it's way. I found the 40 amp 3 phase part number listed at K&G cycles, USMOTOMAN, Dennis kirk (out of stock).

Anywhere else I have missed to price shop?

Be busy this weekend installing new tires and new stator.

They are all drop shipped so you probably need to call to get them. Martin just got his delivered last week and installed over the weekend from K&G