MOSFET convert...

[fret not]

http://www.scribd.com/doc/38765620/SSR-vs-FH012AA is the link.  I am skeptical of sales pitches involving technical information I don't understand.  They may have a winner or it may be more spin.  Until I hear differently from a trusted 3rd party source I remain skeptical. ;)

Still, the MOSFET acts nicely and should be a better unit in the long term than the original one.   :laugh:

[Rikugun]

I've read many in depth descriptions of the internal workings and concepts of the various types of R/R's from very knowledgeable people. In my opinion it's all conjecture. Not to take anything from their expertise in their fields of study mind you. I'm sure their theory is for the most part sound despite not always being in complete agreement with the next experts claims.

As far as I know, no 100% accurate and complete schematics exist of even the older style R/R's. Any schematics in repair manuals are depictions of the main components in so far as to support the testing and diagnosis of them. And I've yet to see any for a MOSFET that would hint at their internal components BTW. The manufacturers have an incentive to keep their proprietary info close to the chest for competitive reasons. They don't freely share the exact details with each other and certainly not with the motorcycling community at large.

I installed a MOSFET with a brand new stator and only time will tell how long lived it is. If it gives good service I guess I can live without knowing all the particulars. Just my 2 cents.  ;)  :)  :D

[jasonm.]

no, I don't think I buy that, the magnets are creating power in the stator. whether you do something with it or not

Not true, when the stator is grounded it's no longer producing power otherwise stators that fail by shorting to ground would continue to function. The scenario I described was used way back when on some Japanese models that utilized current limiters. They were 3 phase full wave systems that had conventional 6 diode rectifiers. Connected in between the 3 sets of 2 rectifier diodes were 3 thyristors (linked to ground) and a zener diode linked to bat + which comprised the "limiter". It sensed and dealt with over charging by systematically shutting down stator legs by grounding them. There may have been 3 different resistors employed as well to incrementally stagger the stator's shutdown. It's been a while and I don't recall all the details.

Automotive and older motorcycle used AC alternators with an excitable DC powered field. AC output was determined by field strength controlled by a mechanical regulator. Whatever AC was made went through a conventional full bridge rectifier to charge the battery. In bikes, although an efficient system, the inherent complexity (both manufacture and diagnosis) and cost to produce was it's demise.

I think when you refer to heat generated by grounding current is the typical scenario described when talking about conventional R/R like the OEM Vision unit and others - maybe even the MOSFET? I never quite understood this explanation or merits of the system but the permanent magnet/stator produces full output all the time relative to RPM and regardless of need. The excess is then "shunted" to ground by the regulating part of the R/R where all the electrons zip around inside the frame forever and ever or until exhaustion and they fall asleep or die.  ???  :D  This system apparently generates lots of heat in both the stator and R/R. The latter was apparently addressed by MOSFET circuitry but not necessarily the former.

FYI...50VAC FROM A STATOR LEG TO GROUND ...IS A SHORT CIRCUIT.NOW THAT'S HEAT. what you may not know. you do not have a 3 leg stator. You actually have ONE wire that is just simply tapped for output in 3 places. "3 leg" in a misnomer. A short to ground measured on the coils anywhere is a short to all.

[Rikugun]

Yes I'm aware there are three legs and obviously they're interconnected as resistance checks are meant to verify.  ;)  The fact is there are or were current limiters in use that shutdown legs by grounding them to reduce output. How much voltage or heat this produces to ground I doubt anyone here is smart enough to know or if it results in more heat than with the stator at full output. I respectfully submit the teams of professionals employed by the manufactureres thought whatever heat may be produced was manageable.

Does one grounded leg completely nullify AC output to the R/R or will there be some output albeit at a reduced rate? The diagrams I've seen show all the legs having circuitry to ground them and in some cases sequentially. This would refute the notion that grounding one leg completely nullifies output as the added cost and complexity of those circuits would be redundant. I'm not convinced the output would be the same measured from A to B, A to C, and B to C under those circumstances. It's been some time since I've encountered one to test so I won't agree or disagree but I have my doubts it's the same. I can't say for sure because I'm one of the non experts here on the ROV.  ;D