Mosfet r/r?

[posplayr]

Thanks for the update, I have ammended the list.



OK. I learn something new every day, can I go home now?

I have more of a "technician" training than "engineer" training, so was unaware of the inner workings. With my background, I was trying to keep it in layman's terms and was building on Rick's understanding: "I know the standard R/R uses diodes(shunt), then they went to diodes and transistors(MOSFET), ..." by saying that they have always had diodes and have always had transistors. Evidently with the newer technology things are changing a bit, but there is still rectification and control, there are just different bits and pieces that are doing the job.

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It might seem a fine detail, but this dynamic rectification using MOSFETs is one of the biggest contributors to efficiency in the R/R itself as differentiated form Shunt vs Series control (where Series is much better overall efficiency including reductions in the stator). For example, the Cycle Elecric upgrades for HD, were probably the first series control R/R's available but they are monsters because they use SCR control with a full 6 diode rectifier. The SCR is not quite as efficient as a MOSFET but those 6 diodes add 2 diode drops per leg (3-4V) that do not exist in the pure "dynamically rectified" versions. You can figure that is probably about 40W difference is power dissipated in the R/R for SERIES control.

http://cycleelectricinc.com/

This is my list, perhaps I need to update if we get any reports on this new Series R/R?

https://www.thegsresources.com/_forum/showthread.php?191795-GS-Stator&p=1630965#post1630965

[Steve]

Out of curiosity, I just explored that link for Cycle Electric. They are nearly in my back yard.

Actually a litte farther away than that (20 miles), but pretty darn close.

Might have to stop by some time and have a chat.

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[posplayr]

Out of curiosity, I just explored that link for Cycle Electric. They are nearly in my back yard.

Actually a litte farther away than that (20 miles), but pretty darn close.

Might have to stop by some time and have a chat.

.

the owner is an old school electronics guy. He was open in discussing his device.

[2BRacing]

....Reading the Roadstercycle.com home page shows there is a SH847 that is a series R/R that was designed with Suzuki for the VStrom 1000 #32800-31J00 . I think it is also with the Polaris #4012941. I have found out they are larger and handle more current.

From following many threads on charging system problems similar to our GS's on other forums (eg. Triumph), I have picked up that besides the fact that the SH847 can handle more current than a SH775, more importantly it can continue to regulate properly at high RPM's (10 000 +) where modern sportbikes rev. The SH775 apparently does not work well at those high RPM's. So the SH847 is really overkill on our GS's.

Just my 2c to add here.

[posplayr]

From following many threads on charging system problems similar to our GS's on other forums (eg. Triumph), I have picked up that besides the fact that the SH847 can handle more current than a SH775, more importantly it can continue to regulate properly at high RPM's (10 000 +) where modern sportbikes rev. The SH775 apparently does not work well at those high RPM's. So the SH847 is really overkill on our GS's.

Just my 2c to add here.

High RPM that might disqualify the SH775 is more like the 15K RPM range. No issues for a GS of any kind.

[hannibal]

You can find 775's on ebay from a seller with the name of (something like...) Powersportsnation. Power sports nation. For one thing, they'll show you the ID on the back end of the unit, unlike a lot of sellers. It'll be either SH775AA or SH775BA. I think one has slightly lower voltage output... not that I've ever tested.

Anyway, their units are usually pretty caked with mud, but I've bought several over the ages and they all work fine. Terrific prices, usually. I just paid $26 for one about two weeks ago.

From what I've seen, BA units have a OEM Polaris part number on them while AA units have a Seadoo part number. Not sure if they function differently or they're just marked differently.

Also, Triumph OEM parts suppliers sell a nice harness that plugs into the SH775 for about $10.