Mosfet r/r?

[Guest]

Has anyone tried this R/R. It's a MOSFET and looks to be a good deal, but I don't want to suggest it for a customer if it the wrong type of upgrade. It even comes with adapters for the wiring.
https://www.ebay.com/itm/Mosfet-Reg...632646&hash=item362aded88c:g:3NMAAOSwBV5ab0tN

 

[Steve]

MOSFET transistors are an improvement over the traditional silicon transistors, but that R/R is still a shunt-style unit. The Shindengen SH775 looks just like it, which is why you have to be so careful when shopping on eBay.

Read the wording on that ad carefully. "Mosfet Regulator Rectifier For Polaris Ranger 800 / Crew 800 / Crew 500 2011". Yes, it is "for" the Ranger, or it "fits" the Ranger, or might even "replace" the R/R for the Ranger, but it is not an exact replacement.

That MOSFET R/R will certainly be a better unit than a broken one, but if you are looking for an inexpensive substitute for an SH775, that is not it. If you look at other eBay offerings that look identical to that one, you will find many Chinese knock-offs in the $20 range. The quick clues are that they are "new" and the country of origin is "China" or "Taiwan". Always look for the picture of the back side of the R/R that shows "SH775" or the Polaris part number in the description.

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[bonanzadave]

Race Tech Electric - Carlsbad CA. Not Race Tech - Corona CA.

Looks like they offer a bunch of Accel and Ricks stuff.

http://racetechelectric.com/b-69125-racetech-electric.html

 

[Guest]

MOSFET transistors are an improvement over the traditional silicon transistors, but that R/R is still a shunt-style unit. The Shindengen SH775 looks just like it, which is why you have to be so careful when shopping on eBay.

Read the wording on that ad carefully. "Mosfet Regulator Rectifier For Polaris Ranger 800 / Crew 800 / Crew 500 2011". Yes, it is "for" the Ranger, or it "fits" the Ranger, or might even "replace" the R/R for the Ranger, but it is not an exact replacement.

That MOSFET R/R will certainly be a better unit than a broken one, but if you are looking for an inexpensive substitute for an SH775, that is not it. If you look at other eBay offerings that look identical to that one, you will find many Chinese knock-offs in the $20 range. The quick clues are that they are "new" and the country of origin is "China" or "Taiwan". Always look for the picture of the back side of the R/R that shows "SH775" or the Polaris part number in the description.

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There are no used ones when I looked earlier and all the other new ones that aren't over $200 are from China with no writing on them at all.

How do you know it is still a shunt style R/R?

Runs much cooler than the traditional Shunt voltage regulator rectifier.

Optimize power delivery by switching the stator coils on or off.

Edit: I did find some used ones after all, but I still would like to know why this one isn't like the SH775. Is the SH775 a MOSFET?

 

[roeme]

I swear, one of these days I'm building (and selling) my own non-shunt R/R.

 

[Guest]

I swear, one of these days I'm building (and selling) my own non-shunt R/R.

If you can and can keep the price under $75 you may become a rich a man.

 

[posplayr]

If you can and can keep the price under $75 you may become a rich a man.

I'm sure they cost $10=-$15 in volume to make.

 

[Guest]

I'm sure they cost $10=-$15 in volume to make.

What do you think of the R/R I posted?

 

[Nessism]

There are tons of used SH775's on ebay. Even some sub $40. Here is one...https://www.ebay.com/itm/EB326-2012...ash=item4415560cd0:g:XQ4AAOSwMfhaYlKD&vxp=mtr

There is another for $30, however there is no photo of the SH775 printing so you should message the guy before buying.

 

[posplayr]

What do you think of the R/R I posted?

Why would you want to even try? Doing R&D?

 

[Guest]

Why would you want to even try? Doing R&D?

I found some used ones. I edited that post, but this one, if it is the same thing, is new and it comes with the parts to adapt it to our bikes.

Is it the same thing as a SH775? Is the SH775 a MOSFET?

 

[posplayr]

I found some used ones. I edited that post, but this one, if it is the same thing, is new and it comes with the parts to adapt it to our bikes.

Is it the same thing as a SH775? Is the SH775 a MOSFET?

The SH775 uses MOSFETS but it is NOT a MOSFET R/R.

 

[Guest]

The SH775 uses MOSFETS but it is NOT a MOSFET R/R.

What IS the difference?

 

[Nessism]

Come on Rick. Forget MOSFET. Think SERIES. Series type R/R's protects the stator from shunted current heating damage. Simple decision.

 

[Guest]

The Series R/R turns on and off to charge instead of shunting through through the stator when not charging. It is not dependent on an expected load so a reduction of a load such as a LED headlight will not fool it into overcharging and damaging the electrical system. Both series and shunt R/R's can use MOSFETS but they work entirely differently. Just because manufacturers like to make cheap **** doesn't mean it is good.

 

[robertbarr]

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.

 

[Steve]

What IS the difference?

The difference is how the MOSFET transistors are used in the circuit. As I mentioned in post #2, MOSFETs are an improvement over silicon transistors. Most transistor designs are rather efficient when they are fully ON or fully OFF. It is during the transition from ON to OFF where they are less efficient and tend to warm up. MOSFET transistors switch from ON to OFF mode quicker, meaning they spend less time in that transition where they build heat, so, yes, they do run cooler. Just like the ad says. But it's only the R/R that runs cooler.

A series-type R/R (like the SH775) could probably use some heavy-duty silicon transistors to do the job. If you really want to get down to it, you could probably use vacuum tubes, but that would tend to offset the efficiency. However, the SH775 does use MOSFET transistors, but only because they are the most efficient way to accomplish the job at a reasonable price.

Because of the difference in operation, the series-type R/R allows the whole system to run cooler. Some feel that the reduction in stator temperature actuall allows the oil to run cooler, because engine oil is sprayed over the stator to keep it cool. Since the stator is cooler, the oil does not have to remove as much heat, so it stays cooler, too.

.

 

[Guest]

Come on Rick. Forget MOSFET. Think SERIES. Series type R/R's protects the stator from shunted current heating damage. Simple decision.

I'm not an electrical engineer. I want to know how they work and what the difference is. It's not about making a decision between the two. Most ads don't mention if it is a series or shunt. I know the standard R/R uses diodes(shunt), then they went to diodes and transistors(MOSFET), which I thought was a series. That doesn't tell me why a SH775 works differently than the MOSFET one that I'm asking about. The ad says different from the traditional shunt type, so that leads me to think it is a series. So is it the same as a SH775 if not why?

 

[Nessism]

I'm not an electrical engineer. I want to know how they work and what the difference is. It's not about making a decision between the two. Most ads don't mention if it is a series or shunt. I know the standard R/R uses diodes(shunt), then they went to diodes and transistors(MOSFET), which I thought was a series. That doesn't tell me why a SH775 works differently than the MOSFET one that I'm asking about. The ad says different from the traditional shunt type, so that leads me to think it is a series. So is it the same as a SH775 if not why?

It's a scam Rick. Those cheap chinese knockoffs are everywhere. They are NOT series type. Do what you want though. Everyone here has told you the truth but you don't want to listen.

 

[posplayr]

I'm not an electrical engineer. I want to know how they work and what the difference is. It's not about making a decision between the two. Most ads don't mention if it is a series or shunt. I know the standard R/R uses diodes(shunt), then they went to diodes and transistors(MOSFET), which I thought was a series. That doesn't tell me why a SH775 works differently than the MOSFET one that I'm asking about. The ad says different from the traditional shunt type, so that leads me to think it is a series. So is it the same as a SH775 if not why?

https://www.thegsresources.com/_forum/showthread.php?161397-Compu-Fire-SERIES-R-R-Install


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