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http://www.crowitis.com/images/About Our Stator...And How It Is Affected By The System Load.pdf

Read the third paragraph. Maybe they are wrong and you are right. I don't know. I said I don't understand electrical stuff but do understand physics...wasn't saying I was right,just that's how it looks from a physics viewpoint.

A microwave cooks food because it converts ALOT of electrical energy into those microwaves...decrease the power and it cooks slower...so not sure what you're saying here now.
I am saying electrical was my field of study. I look at things from that standpoint.

The microwave reference was an illustration of how heat is formed by electron movement. Crude as it may be. All I am saying is, any time a coil wrapped around an iron core is passed through a magnetic field is it induces voltage which, is by definition, electrons on the surface of the wires in the coil moving. If they have nowhere to go they won't move as fast but start bumping into each other and will produce heat even if that field is not rotating. It is likely only on one leg of a triple wound coil like we are dealing with and probably almost immeasurable but it is there, no matter what an internet article says. Bonjour ;)

Any way we are still kinda off topic here but that could be part of the reason we have a single leg failure in most stators, That is highly debateable but not out of the realm of possibility since most v-twins will usually stop at one of two points during normal shutdown.

I stand by my statement .
 

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I'll gladly give you the nod here as I do know not everything you find online is true. This discussion really isn't off topic because it deals with how the stator works and that's an important thing to understand when picking an R/R for your bike. It was in the OP's first post the idea of putting less strain on the stator. We both agree that heat is the underlying cause of stator failure. So this in my view is on topic.
You believe those moving electrons are producing heat even if the stator wires are turned off ...but we don't know how much heat this really is, and if it's basicly moot because the oil around the stator is hotter.

I was in no way questioning your knowledge but only looking for a rational explanation. In science "potential energy" really means zero energy. If I hold a brick over your head, we can calculate the "potential energy" it has -if I drop it- if we know the weight of the brick and the distance from your head.
If I never drop it the potential energy never happens.


If you say potential voltage, I see the same thing. My thinking is- You only get voltage or current if you complete the circuit. If the only way to detect it is to use a Voltmeter to measure it...which by its own use completes the circuit, you need to tell me how you can prove current exists there without using that form of measurement. If you can't prove it, how do you know it exists? ;)

(Wow that sounds familiar ....;) )
 

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I'll gladly give you the nod here as I do know not everything you find online is true. This discussion really isn't off topic because it deals with how the stator works and that's an important thing to understand when picking an R/R for your bike. It was in the OP's first post the idea of putting less strain on the stator. We both agree that heat is the underlying cause of stator failure. So this in my view is on topic.
You believe those moving electrons are producing heat even if the stator wires are turned off ...but we don't know how much heat this really is, and if it's basicly moot because the oil around the stator is hotter.

I was in no way questioning your knowledge but only looking for a rational explanation. In science "potential energy" really means zero energy. If I hold a brick over your head, we can calculate the "potential energy" it has -if I drop it- if we know the weight of the brick and the distance from your head.
If I never drop it the potential energy never happens.


If you say potential voltage, I see the same thing. My thinking is- You only get voltage or current if you complete the circuit. If the only way to detect it is to use a Voltmeter to measure it...which by its own use completes the circuit, you need to tell me how you can prove current exists there without using that form of measurement. If you can't prove it, how do you know it exists? ;)

(Wow that sounds familiar ....;) )
Don't I know it, lol
I see where we are miscommunicating. You are looking at Potential from a physical standpoint, potential and voltage are interchageable words in electrical speak. The true definition of voltage is Electromotive Force . Most people throw the words power and voltage around as the same thing. They are not. Lets see if I can explain this better.
Ohms law as it was taught to me is P=E x I. In common everyday terms that doesn't mean squat to most people. Here P means power(expressed in amps or watts . E means Electromotive force( usually expressed in volts) I means resistance (expressed in Ohms)

Now for the simplified version A = V x R . I am going to assume we are on the same page now as for verbage.

Prove it you say with out a meter , I will with math.

first lets talk about Resistance , a coil will always have resistance. You are going to have to take my word for it or you can read in the service manual about checking the resistance of the windings in the stator or you can do the test your self by taking a long piece of wire and checking it with an ohm meter then wrap that same wire around an iron center rod and just leave a little on each end, you will find resistance is higher, really you will. Maybe not a lot but higher nonetheless'

You will stipulate that a coil passed through a magnetic field produces voltage, I am sure.

Did I mention I hate math? Here goes,, anyway. If A =VxR then we can know that _A_ means whichever value we want to find we can if we have two
V x R
known values either by multiplication or division ,correct ?

If you already know that a coil inside a magnetic field produces voltage and you know that a coil has resistance you have to also know that there is amperage being produced ,no matter it is immeasurable with out a meter, Logic will tell you it is there, okay? say the resistance of the coil is one ohm and just for giggles the voltage produced by that coil is 1 volt, the principle of OHMs law means 1 x1 = 1 amp being burned off in the form of heat.

Those numbers are no where near the real values but were just used for illustration. Is that so unbelievable ?

Now I am going to prove that you can test it with a meter while the engine is off. What?? for voltage ..... yes, since this is a three phase ac alternator and one leg is producing voltage all the time ,why doe it show zero voltage on 200 VAC scale? Because it will be producing a very low DC voltage . Because with the rotor stationary only one leg of the windings is being excited and will only produce half of a sine wave, which is DC. Chew on that a while.
 

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Well .....that actually made sense to me.

And I do know from an audio viewpoint half a sine wave still produces sound.

The one issue I've always had a concern about was those that start replacing all their lights with LED's. Seems to me that all they are doing is making the R/R send more voltage to ground (unless they are adding electrical accessories that bring voltage demand back up) which, correct me if I'm wrong here, is basicly "shorting out" voltage and putting more "strain" on the stator.
 

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Well .....that actually made sense to me.

And I do know from an audio viewpoint half a sine wave still produces sound.

The one issue I've always had a concern about was those that start replacing all their lights with LED's. Seems to me that all they are doing is making the R/R send more voltage to ground (unless they are adding electrical accessories that bring voltage demand back up) which, correct me if I'm wrong here, is basicly "shorting out" voltage and putting more "strain" on the stator.
Thank you and I subscribe to the same view point on the "unloading" the electrical system ,it would seem to me it would run the best at or close to the max load carrying limits to be it's most efficient. I actually stated that in an earlier post.

I am glad that made sense It was like typing a novel. :beerchug:
 

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Discussion Starter #26
I found a thread on xlforum.net that the guy monitors both the stator output in amps and the voltage @ battery simutaniously with both a mosfet and a series r/r. http://xlforum.net/vbportal/forums/archive/index.php/t-1648679.html
Page 1 he tests the mosfet and around page 4 is the series. With the mosfet stator is producing 26A @ 2K+ rpm series type 12A, only the system load.
 

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Discussion Starter #27
Kanuck The reason you still read voltage with the meter is because the meter completes the circuit internally , complete circuit, and only drawing the load of the meter, but still same voltage
 

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I found a thread on xlforum.net that the guy monitors both the stator output in amps and the voltage @ battery simutaniously with both a mosfet and a series r/r. http://xlforum.net/vbportal/forums/archive/index.php/t-1648679.html
Page 1 he tests the mosfet and around page 4 is the series. With the mosfet stator is producing 26A @ 2K+ rpm series type 12A, only the system load.
Nice. So here's a valid reason to install LED lighting ...wonder how many amps that save?
 

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This is how I understand things: the rotor (permanent magnet) rotates around the coils (stator) this causes the wires in the coils to cut lines of magnetic flux and produce an AC voltage or potential difference proportional to the speed of the rotor (up to a point). At zero RPM there is no voltage produced. For practical purposes no current (amperes) is drawn until the coils are connected to a load. if no current is flowing, then no power (watts) is being generated by the coils (stator). If no current is flowing in the coils then no power is being produced and there is no heating of the wires that make up the coils (current squared X resistance looses). If it were possible to switch all three phases on and off to regulate the rectified output to a smooth 14 volts DC then that would run the stator at lower power if the load on it (charging plus lights etc) were at a low state. However, given that we have a regulator set up that shunts excess voltage to ground thus running the stator at maximum power generation at all times, yes I agree, it is best to run enough electrical systems to use pretty much all the stator can produce in order to limit the amount of current the regulator is passing to ground in order to limit the voltage to 14 ish volts. Does any of that help? I have most likely just said what everyone else said, in a slightly different way !
 

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Nice. So here's a valid reason to install LED lighting ...wonder how many amps that save?
There is a valid reason to run Led lighting for sure, To have more power freed up for the accesories so many of us like to use :)

This is how I understand things: the rotor (permanent magnet) rotates around the coils (stator) this causes the wires in the coils to cut lines of magnetic flux and produce an AC voltage or potential difference proportional to the speed of the rotor (up to a point). At zero RPM there is no voltage produced. For practical purposes no current (amperes) is drawn until the coils are connected to a load. if no current is flowing, then no power (watts) is being generated by the coils (stator). If no current is flowing in the coils then no power is being produced and there is no heating of the wires that make up the coils (current squared X resistance looses). If it were possible to switch all three phases on and off to regulate the rectified output to a smooth 14 volts DC then that would run the stator at lower power if the load on it (charging plus lights etc) were at a low state. However, given that we have a regulator set up that shunts excess voltage to ground thus running the stator at maximum power generation at all times, yes I agree, it is best to run enough electrical systems to use pretty much all the stator can produce in order to limit the amount of current the regulator is passing to ground in order to limit the voltage to 14 ish volts. Does any of that help? I have most likely just said what everyone else said, in a slightly different way !
I addressed how voltage is always being produced even with the rotor stationary in another post and I'm on solid ground with my statement,no biggie though.

The one thing that did throw me is you said "ground" instead of "earth" ;) Are you sure you're a Brit ?? Just Kidding ,lol
 

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Yes, but no one believes you..... ;)
I've learned to live with that fact over the years. People are going to believe what they want, no matter the facts or evidence presented. Al Sharpton would be dead broke otherwise:)
 

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I've learned to live with that fact over the years. People are going to believe what they want, no matter the facts or evidence presented.
Yep. Said this about evolution and climate change for years now...:)

Anyway....it's going to be in the 50's tomorrow, going to charge up my new battery, go for a ride , and not worry about what my stator does or doesn't do....
 

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I cannot see how you can produce a potential difference across a coil placed next to a stationary magnetic field. The wire in the coils has to cut the magnetic flux to get an induced voltage. Either the magnet has to move, or the coil has to move. With the engine not moving there is no voltage at any of the three phases measured in any combination. You don't have to take my word, just cut all three of your stator wires and tell me how many volts you get with nothing moving, from any of them, to each other or to ground/earth/chassis. Mind you, maybe the laws of physics are different on the other side of the water ?
 

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I cannot see how you can produce a potential difference across a coil placed next to a stationary magnetic field. The wire in the coils has to cut the magnetic flux to get an induced voltage. Either the magnet has to move, or the coil has to move. With the engine not moving there is no voltage at any of the three phases measured in any combination. You don't have to take my word, just cut all three of your stator wires and tell me how many volts you get with nothing moving, from any of them, to each other or to ground/earth/chassis. Mind you, maybe the laws of physics are different on the other side of the water ?
I will ask you another question then. No offense meant by the ground earth question ,just a little good natured ribbing .

How then does a transformer work with no moving parts ? I know it doesn't work with no voltage on the primary side, but the primary side is powered up to produce a magnetic field. A permanent magnet is always on and the three legs are always or at least one is in it according to rotor position in relation to the winding. I didn't say it produced a great amount of voltage but one winding will be producing a small DC voltage. Is it enough voltage to pass through the R/R , no and it is a small DC voltage with the emphasis on small.

I am not cutting my stator wires to prove it. I know how inductance and reluctance work.

Just think about it a bit is all I ask.
Have a good day on the other side of the pond:beerchug:
 

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transformers work simply because the primary side magnetic field changes, due to change in voltage applied/current conducted, and that changing magnetic field produces the same effect as a moving magnet does.

a stationary coil of wire in a stationary (no variance in polarity or strength) magnetic field does not produce any measurable potential (voltage) and there for cannot supply any current (it takes voltage to make current flow)
 

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Everything I've read says you can't get voltage in a coil of wire with a permanent magnet unless it's moving....or the coil is. Period.

And everything I've read so far says that even if it's moving , and nothing is connected to the ends of the coil, no current is flowing.

You can call it "potential voltage" if you want, but saying its producing heat seems even more unlikely.

If it's "immeasurable" then again, you're not proving it exsists.

I'm from the "Show Me State"....so you'd have to show me how any of this possible. Math equations are useless when you don't have the numbers to stick in.....remember zero times any number is still zero.

Again not saying you're wrong, just that you have no physical proof to display...
 

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Exactly. It is the AC primary that makes the transformer work. Because the voltage is a sign wave, the magnetic flux is following the same (more or less) pattern. The point to remember is that voltage is only induced in a wire if that wire cuts across lines of magnetic flux. Either the flux has to be moving (or collapsing/growing) or the wire has to be moving. If you put DC into the primary of a transformer you will only see a spike of voltage across the secondary as you connect and disconnect the primary. An ignition coil is a transformer, the collapsing DC on the primary induces a voltage on the secondary. At steady state there is no induction and no voltage produced at the secondary. No offence taken at the ground/earth thing. One has to get very up front and personal to get any sort of raise out of me. Even then I just smile and walk away. After all, I am an Englishman.
 

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Ok , I give up , happy? Not offended either because after all, I am an Idiot and don't know anything and just don't know any better :)
 

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Hey cool I thought I was the only idiot here.glad more of my kind are here;)
 
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