Forums

Re: Automotive alternator windings & rectifier

Started by Mike Cook August 19, 2013
>> http://www.autoshop101.com/forms/alt_bwoh.pdf >> >> has photos of an alternator with 4 connections for windings (each of 3 >> phases + common), > > Not one of the pages shows four connections brought out from the > windings.
Photo on p. 18.
>> and the 8 diode rectifier. > > I don't see any 8 diode rectifier.
Photo on p. 25. Note callouts for 6 diodes but you can see 8 round circles -- those are the diodes. Eight. (And yes, I've seen the rectifier and each of the 8 have leads soldered to each bus (or something...). I can confirm that firsthand.) My conundrum remains:
>> But wiring diagrams show only 3 connections and 6 diodes.
>> Where does the common winding terminal connect (there is a connection on the >> rectifier plate)? Where do the other 2 diodes connect? > > Common is created by the way the diodes are connected. >THAT< common is > connected to the auto frame.
By "common" are you referring to the (-) terminal? We agree that that terminal goes to chassis (presuming neg. ground chassis). I'm talking about the common point among all 3 windings -- the center terminal of the "Y" configuration.
> Would you ask your question again and maybe clarify the situation?
There ya' go... Thanks.
On 20/08/13 09:23, Mike Cook wrote:
>>> http://www.autoshop101.com/forms/alt_bwoh.pdf >>> >>> has photos of an alternator with 4 connections for windings (each of 3 >>> phases + common), >> >> Not one of the pages shows four connections brought out from the >> windings. > > Photo on p. 18. > >>> and the 8 diode rectifier. >> >> I don't see any 8 diode rectifier. > > Photo on p. 25. Note callouts for 6 diodes but you can see 8 round circles -- > those are the diodes. Eight. (And yes, I've seen the rectifier and each of > the 8 have leads soldered to each bus (or something...). I can confirm that > firsthand.) > > My conundrum remains: > >>> But wiring diagrams show only 3 connections and 6 diodes. > >>> Where does the common winding terminal connect (there is a connection on the >>> rectifier plate)? Where do the other 2 diodes connect? >> >> Common is created by the way the diodes are connected. >THAT< common is >> connected to the auto frame. > > By "common" are you referring to the (-) terminal? We agree that that > terminal goes to chassis (presuming neg. ground chassis). > > I'm talking about the common point among all 3 windings -- the center > terminal of the "Y" configuration. > >> Would you ask your question again and maybe clarify the situation? > > There ya' go... > > Thanks. >
afaik the common of the 'Y' does not connect anywhere else. To do so would make it a "Wye" setup.
On 8/19/2013 8:23 PM, Mike Cook wrote:
>>> http://www.autoshop101.com/forms/alt_bwoh.pdf >>> >>> has photos of an alternator with 4 connections for windings (each of 3 >>> phases + common), >> >> Not one of the pages shows four connections brought out from the >> windings. > > Photo on p. 18. > >>> and the 8 diode rectifier. >>
You're right, I'm wrong. I see the four a little hidden by the picture angle.
>> I don't see any 8 diode rectifier. > > Photo on p. 25. Note callouts for 6 diodes but you can see 8 round circles -- > those are the diodes. Eight. (And yes, I've seen the rectifier and each of > the 8 have leads soldered to each bus (or something...). I can confirm that > firsthand.) >
I'll take that as so, but I don't see it.
> My conundrum remains: > >>> But wiring diagrams show only 3 connections and 6 diodes. > >>> Where does the common winding terminal connect (there is a connection on the >>> rectifier plate)? Where do the other 2 diodes connect? >> >> Common is created by the way the diodes are connected. >THAT< common is >> connected to the auto frame. > > By "common" are you referring to the (-) terminal? We agree that that > terminal goes to chassis (presuming neg. ground chassis). > > I'm talking about the common point among all 3 windings -- the center > terminal of the "Y" configuration. > >> Would you ask your question again and maybe clarify the situation? > > There ya' go... > > Thanks. >
On 8/19/2013 9:23 PM, Mike Cook wrote:
>>> http://www.autoshop101.com/forms/alt_bwoh.pdf >>> >>> has photos of an alternator with 4 connections for windings (each of 3 >>> phases + common), >> >> Not one of the pages shows four connections brought out from the >> windings. > > Photo on p. 18. > >>> and the 8 diode rectifier. >> >> I don't see any 8 diode rectifier. > > Photo on p. 25. Note callouts for 6 diodes but you can see 8 round circles -- > those are the diodes. Eight. (And yes, I've seen the rectifier and each of > the 8 have leads soldered to each bus (or something...). I can confirm that > firsthand.) > > My conundrum remains: > >>> But wiring diagrams show only 3 connections and 6 diodes. > >>> Where does the common winding terminal connect (there is a connection on the >>> rectifier plate)? Where do the other 2 diodes connect? >> >> Common is created by the way the diodes are connected. >THAT< common is >> connected to the auto frame. > > By "common" are you referring to the (-) terminal? We agree that that > terminal goes to chassis (presuming neg. ground chassis). > > I'm talking about the common point among all 3 windings -- the center > terminal of the "Y" configuration. > >> Would you ask your question again and maybe clarify the situation? > > There ya' go... > > Thanks. >
The + and - from the six diodes is connected to a series pair of diodes. The junction of that pair goes to the neutral junction of the stator coils and the regulator. Like this: + --->|---+--->|--- - | | Neutral Junction-+->to regulator See http://autonopedia.org/renewable-energy/generators/alternator-secrets/ Ed
> afaik the common of the 'Y' does not connect anywhere else. > To do so would make it a "Wye" setup.
A "Y" = "Wye". "Wye" is just a way of sounding the letter "Y". They are one and the same.