This circuit was modified by a friend (Tom ) for his 6 volt honda vintage bike CT90 that was needing a voltage regulator. He derived this from my previous post of 12 volt single phase motorcycle voltage regulator FULL WAVE. With only minimal changes with the values created the hard to find regulator for 6 volt charging system.
CIRCUIT CHANGES and description
Use:6 volt Regulator Rectifier for 1976 Honda CT90 (permanent magnet alternator)
Base circuit:"full wave regulator" single phase 12 volts regulator
Circuit mods:Results were collected with the following modifications to accommodate a 6 volt systems:
R2 & R4 values = 470 ohms
C1 = 22uF 50v
SCR's = S6025L 25amp 600 volt Heat sinks a must even with short testing
Bridge rectifier = purchased 35 amp 600 volt AC, 1000 volt DC
Zener diodes as shown below
R3 values as shown below
Regulation output as shown:No load & Headlight on
With zener 1N4733 (5.1v)various RPM's
R3 2.7K ohms 6.6v stable 5.9v +/- .25v load.
R3 3.3K ohms 6.9v stable 6.3v +/- .25v load
R3 3.6K ohms 7.1v stable 6.4 +/- .25v load
With zener 1N4734 (5.6v)various RPM's
R3 2.7K ohms7.3v stable 6.6v +/- .25v load*
R3 3.3K ohms7.6v stable 6.9v +/- .25v load
R3 3.6K ohms7.8v stable 7.1v +/- .25v load
Thanks to Sir Tom, cheers mate.
CIRCUIT CHANGES and description
Use:6 volt Regulator Rectifier for 1976 Honda CT90 (permanent magnet alternator)
Base circuit:"full wave regulator" single phase 12 volts regulator
Circuit mods:Results were collected with the following modifications to accommodate a 6 volt systems:
R2 & R4 values = 470 ohms
C1 = 22uF 50v
SCR's = S6025L 25amp 600 volt Heat sinks a must even with short testing
Bridge rectifier = purchased 35 amp 600 volt AC, 1000 volt DC
Zener diodes as shown below
R3 values as shown below
Regulation output as shown:No load & Headlight on
With zener 1N4733 (5.1v)various RPM's
R3 2.7K ohms 6.6v stable 5.9v +/- .25v load.
R3 3.3K ohms 6.9v stable 6.3v +/- .25v load
R3 3.6K ohms 7.1v stable 6.4 +/- .25v load
With zener 1N4734 (5.6v)various RPM's
R3 2.7K ohms7.3v stable 6.6v +/- .25v load*
R3 3.3K ohms7.6v stable 6.9v +/- .25v load
R3 3.6K ohms7.8v stable 7.1v +/- .25v load
Thanks to Sir Tom, cheers mate.
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| Picture borrowed from Sir TOM who actually made the 6 volt system |


Hi, I want 6.9 volt with bulbs on and off. Which R 3 and others should In take ?
ReplyDeleteDo you have Road experience with this device on a Honda CT 90 ?