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Discussion Starter #1
anyone used one on a cb360? I'm putting mine back together and the original design is just so............. bunglefucked, that I'm thinking of building a box that handles the rectifier, regulator, starter relay (mosfet), etc... if anyone has any suggestions as to why honda only used two phases of the alternator on this bike too, they'd be appreciated
 

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It uses 3 phases, one gets switched in when lights turn on so it doesn't overcharge when lights are off

PJ
 

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It uses 3 phases, one gets switched in when lights turn on so it doesn't overcharge when lights are off

PJ
 

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Just about every regulator in the world will take the extra voltage and shunt to ground. The current has to go somewhere, which is why they don't open the circuit instead. If you opened the circuit, the voltage would actually rise, which isn't really what you want.
 

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Just about every regulator in the world will take the extra voltage and shunt to ground. The current has to go somewhere, which is why they don't open the circuit instead. If you opened the circuit, the voltage would actually rise, which isn't really what you want.
 

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Discussion Starter #8
ok... if that's the case, I'll definitely be building a switch mode regulator to keep the system voltage at or below 13 or so. should take some load off the alternator too since it will just modulate the output without shorting anything to ground
 

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Discussion Starter #9
ok... if that's the case, I'll definitely be building a switch mode regulator to keep the system voltage at or below 13 or so. should take some load off the alternator too since it will just modulate the output without shorting anything to ground
 

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I guess that's the difference between electronics and electrical systems, knows how to build a switched regulator but doesn't know what it does :D
It wont take any load off a PMS system, the magnet still spins.

PJ
 

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I guess that's the difference between electronics and electrical systems, knows how to build a switched regulator but doesn't know what it does :D
It wont take any load off a PMS system, the magnet still spins.

PJ
 

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Yup, the current component that I mentioned is really important. The power source here is inductive and acts as a current source. Such things don't take well to instantaneous current changes, and you'll end up with a LOT of voltage building up in the coil, maybe 120V. They are designed to be shunted, it doesn't load the system down like you'd expect with a voltage source. The extra current gets recirculated, no harm in that.

The goal is admirable though. I keep looking at my old KZ's electrical system (which isn't that bad really) and thinking how cool it would be to make a unified box. Replacing a starter relay with a MOSFET circuit would be an interesting challenge, I expect the kickback would be pretty heavy. Lights are easy, they're resistive loads and you could do all kinds of cool modulations. Maybe some big fat Schottky rectifiers for that part to keep the heat down, Triac shunts for regulation. Points replacement would be fun too, you could get into all kinds of trouble playing with timing curves.
 

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Yup, the current component that I mentioned is really important. The power source here is inductive and acts as a current source. Such things don't take well to instantaneous current changes, and you'll end up with a LOT of voltage building up in the coil, maybe 120V. They are designed to be shunted, it doesn't load the system down like you'd expect with a voltage source. The extra current gets recirculated, no harm in that.

The goal is admirable though. I keep looking at my old KZ's electrical system (which isn't that bad really) and thinking how cool it would be to make a unified box. Replacing a starter relay with a MOSFET circuit would be an interesting challenge, I expect the kickback would be pretty heavy. Lights are easy, they're resistive loads and you could do all kinds of cool modulations. Maybe some big fat Schottky rectifiers for that part to keep the heat down, Triac shunts for regulation. Points replacement would be fun too, you could get into all kinds of trouble playing with timing curves.
 

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Discussion Starter #14
knows how to build a switched regulator but doesn't know what it does


uhm, actually it would take load off the alternator. the resistance to the flux change caused by the magnets alternating polarity through the coils is proportional to the load on the coil. if the coils are open, there will be no resistance other than eddy currents in the core, which is laminated to eliminate them.

it's switch mode also, not a switch regulator. it operates at a fixed frequency and alters the duty cycle to vary voltage into the battery and system load

btw, my regulator is working fine now, providing up to but not over 15V to the battery
 

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Discussion Starter #15
knows how to build a switched regulator but doesn't know what it does


uhm, actually it would take load off the alternator. the resistance to the flux change caused by the magnets alternating polarity through the coils is proportional to the load on the coil. if the coils are open, there will be no resistance other than eddy currents in the core, which is laminated to eliminate them.

it's switch mode also, not a switch regulator. it operates at a fixed frequency and alters the duty cycle to vary voltage into the battery and system load

btw, my regulator is working fine now, providing up to but not over 15V to the battery
 

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get a sparx or tympanium solid state three phase rectifier/regulator unit

problem solved

will work well and last a long time
 

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quote:Originally posted by dielectric

Yup, the current component that I mentioned is really important. The power source here is inductive and acts as a current source. Such things don't take well to instantaneous current changes, and you'll end up with a LOT of voltage building up in the coil, maybe 120V. They are designed to be shunted, it doesn't load the system down like you'd expect with a voltage source. The extra current gets recirculated, no harm in that.
I'm not an electrical engineer, I'm bike mechanic with a lot of experience.
I've measured 118 no load AC volts on a Honda C50 (6 volt system)
Most permanent magnet systems will make 60~70 AC volts @3~5,000 rpm, switching on/off spikes about 320V with PVA.
350 will spin to 10,500 rpm pretty easy, don't know what that does to voltage but I'm sure someone here can work it out. :D

PJ
 

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peak or rms?
 

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Discussion Starter #19
a multimeter isn't going to give you a very accurate reading off an alternator without some kind of resistance in the circuit, it's still farraday's law in the end... but anyhow, a switch mode regulator is a good solution to the problem of providing a regulated dc voltage from an unregulated ac supply, proof is in the pudding I guess
 
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