Bold claim about XZ550 Stator

[jasonm.]

H2O, My too many years in elctronics tells me you are probably causing your own problems by running 2- 55w driving lights. Now are surely overtaxing the charging system. That means even w/o the brake on you are required to pump ~ 300 watts. Guess what, you most likely don't have 300 watts available most of the time. You are not doing yourself any favors using the driving lights. Just run your hi-beam in the day and get a quality quartz bulb. I have a Venture w/420w alternator for 20 years. I can only run my 55w pair when on the hiway. Otherwise the voltage really drops. Just so you know...my stator in the Venture is perfect. I suspect your problem got worse w/driving lights installed. As my voltage never drops as low as yours. TAKE THE DAMN DRIVING LIGHTS OFF..... ::)

[Brian Moffet]

If I remember correctly, there are a few things to think about:

1) The rectifier/regulator draws maximum power from the stator, anything it doesn't use it dumps to ground (heat at the regulator)
2) Drawing maximum power from the stator means it always has maximum heat dissipation in the stator for a given RPM
3) The maximum power that can be produced depends on the size of the magnets, the placement of the magnets, and the RPM.

Can we agree on the above?

If so, then why does putting additional load on the far side of the R/R cause more power to be drawn from the stator at a given RPM?

Oh yes, please feel free to get as technical as you need, I can keep up in that area.

Brian

[h2olawyer]

The driving lights made no difference in stator life.  Same with as without.  Why would I have gone through stators at the same rate before adding the lights as I do after I added them?  THE LIGHTS STAY ON!  They are not the problem.  I will eventually swap to 35w bulbs, but 1000 mile stator life was happening for several stators before the lights were added.

Brian is correct - As I've been led to understand, the stator puts out full power all the time, no matter what power requirements are being requested.  Trying to use all the available power from the stator puts no extra strain on the system.  When the max power is asked for, nothing really changes except that little or no power is shunted to ground or converted to heat, the battery charges slower & the R/R has a bit less to do.

I've done all I can for now.  I'll just wait until I get past the magic 1000 miles on the bike and see if the stator is still running.  That should happen on the next ride - whenever that may be.

I appreciate the help, everyone here has had suggestions over the years.  I've tried them all & nothing has changed.  I tried using no more power than the basics on the bike require.  I tried using all the available wattage.  I tried using some extra wattage.  I tried soldering connections.  I examined the wiring harness.  I tried different brands of stators (including OEM).  The only thing that made a difference was when I got a second new R/R (aftermarket type - not  OEM) that gave me 1500 miles before the regulating side died.  I put the old R/R back in & voila - another 1000 miles & the stator died.  That stator went 2500 miles - a 150% improvement WITH THE LIGHTS.  It was most likely (98.987456872682287% sure) the old R/R.  I installed a new aftermarket type R/R @ the same time as the last stator.  If I can get 4500 - 5000 miles out of a stator, I'll call it good.  That will get me through 2 or 3 years of riding.

H₂O

[Walt_M.]

As H2O has stated(so many times that he must be getting tired of it) additional load on the electrical system does not cause extra burden on the stator. Its output is the same, approx 22 amps. The only downside to additional load is reduced battery charging capability. No problem on shorter(less than 300-500 miles) runs and nightly battery charges.
The stator insulation eventually deteriorates until it can no longer keep the vibration of the windings from going into ground contact, shorting and burning the stator out. (I'm  getting a little tired of having to repeat my explanation too). 

[QBS]

I think the idea of protecting the windings' insulation from the sharp angles of the stator chassis has got to be a major step in the right direction.

[akvision]

Thanks guys.... Wisdom has spread... your threads are appreciated..
'rhpaw' says I need  the install my spare stator on Sept 17, before we head for New Mexico.
I feel confident after going over and over it.

I think that H2O is a magnetic personalitiy and maybe needs to ride with us to Roswell to find out the "Truth" ::)

[h2olawyer]

It's sort of funny - I have no problem with wearing a wristwatch (other than I find them uncomfortable after a few minutes) but I have had charging issues with nearly every vehicle I've ever owned.  I think I'm just snakebit when it comes to electrical power generation.

I'd love to go to Roswell with y'all, but I'll be in the panhandle of Oklahoma for the week enjoying some very dark skies, taking some pretty astrophotos & otherwise hobnobbing with some of the more famous amateur astronomers @ the Okie-Tex Star Party.  I've heard some wonderful reports about that party & am really looking forward to the experience.  Six nights of seeing the Milky Way stretching from horizon to horizon (weather permitting).  My cousin will be there with his 16 inch scope & will be one of the featured speakers.  Not sure if he'll be talking about imaging Arp Galaxies or doing his "Dermal Philosophical Telescope" which allows attendees to 'touch the light of far away worlds'.

H₂O

[jasonm.]

H2O, why do you think you can defy the laws of physics? On a good day, you have a 280w alternator. You have a constant load near that and more ALL the time.  How come you think your Vision can run more electrical load than an '82 Gold Wing which has a 350w alternator. Which is another(same vintage) bike known to burn stators when overloaded w/2 driving lights. WHEN did your 1000 mile/stator loss , start???  Have you had this issue since the day you bought this 'V'  ?   Everything has it's limits. Live within them. Your voltmeter does not tell the whole story of how the system is working. Take the lights off and start over.   If you don't want to believe what I am saying. You are bound to keep repeating your results. PS- don't buy chinese parts.

[Brian Moffet]

Jason, could you answer my questions please (see about 6 messages above.)  My understanding of the physics obviously does not jibe with your understanding of the physics...

[jasonm.]

Brian, I agree mostly what you say 1 & 3. But the R/R does not draw in the typical sense. It's simply is a passive diode fullwave bridge rectifying filter. Changing A/C to DC and regulating the DC to approx. 14-15v.  If you give it 20vac it works with that ....give it 100vac it works with that. The size of the diodes determine it MAX. input it can handle. these old style units= MOre input the hotter it gets. The draw is from the load of the entire bikes electrical load. My Venture R/R is the same design but bigger...bigger internals(diodes).  If you do exceed any component's design. Requesting too much output(watts/amps) or exceeding design input(oversized stator) ...things break.

[Brian Moffet]

The size of the diodes determine it MAX. input it can handle. these old style units= MOre input the hotter it gets. The draw is from the load of the entire bikes electrical load.

So this is basically saying that the heat problem is in the R/R, not the stator, correct? (which is what I have argued all along). 

Of course, if your R/R should drop down its internal resistance due to a short, then a fair portion of the power dissipation will occur in the stator, but what would likely happen is an open circuit due to the heat.  That makes the stator circuitry open, which means no power, correct?

[thisandthat]

Is this diagram agreed to be accurate?
And your correct the stator will supply the maximum current and therefor maximum power when it views the outside world (in our case the RR) as a short.

[h2olawyer]

My stator issues started @ 4500 miles.  I replaced BOTH the stator & R/R at that time.  Was not running any extra electrical loads at all.  None, zip, nada (typing again).  I went through three or four stators before trying to use more of the electricity from the stator.  Always with the  same results.  (this is like deja-vu all over again & again - think I could type this while unconscious now).  The lights were an addition two or three stators ago.  They made no difference.

What did improve stator life was a change of the R/R (haven't I typed this many times before?)  Me last stator endured 2500 miles or 2.5 times longer than any since the OEM stator died.  The R/R lasted 1500 of those miles before it stopped regulating.  The stator was still fine.  I put the previous R/R on and got 1000 additional miles out of the stator before it died.  (wow, this sounds familiar)

I now have another new R/R and stator installed at the same time and all is working well.  The last new R/R had occasional short voltage spikes about 3 months after installation.  This one is showing none of those and the volt gauge runs rock steady.

I appreciate the help, but as I've stated before, I am about 98.09823469348659348076023876520387% sure the problem is solved - or at least much improved.  By the way, the first defective R/R was a Japanese unit - not Chinese (which I agree is likely even worse).

I have charging system gremlins that love nearly every vehicle I've ever owned & always present an 'odd' problem.  Once the failures are found, they are of the "hmmmmmm - I've never heard of that before" type when I discuss them with knowledgable people.  As an example, I've now had two R/Rs that were faulty from new.  Anyone could have received them, but I was the lucky one.

H₂O

[jasonm.]

Ok...H2O...have you tried changing the flywheel? There maybe an issue w/ the magnets.  Also to those out their saying max. power delivered all the time. Correct term is the R/R only gives "Max of what's available". NOT max all the time. Otherwise you'd have max. watts/amps available at idle. And we all know that is NOT possible due to the low rpms. That diagram is pretty much simplified as accurate. There is more to the regulator.

[Re-Vision]

The current draw on a stator that is being regulated within its design limits will be dropping a constant 22 Amps to ground at all times whether its at the switching transistors or through fused loads.  When the load increases to the level that the regulator can not maintain its lowest regulated DC output voltage then the stator output AC voltage will rise in an attempt to bring the regulator back within its regulatory range, this increase in stator voltage will cause maximum unregulated current to flow to ground (Load current plus current to ground through switching transistors).  This increased AC input Voltage will push max Amps through the loads and load resistance will decrease until heat buildup reachs a point that the weak link (R/R or stator) will fail. Thats my theory and I'm sticking to it. BDC

[Brian Moffet]

NOT max all the time.

Yup, which is why I specified max for a given RPM...   ;)

Brian

[thisandthat]

I'm fairly sure, although I can't find the proper theory behind this, that the voltage that the stator puts out is only related to RPM, windings, and magnetic field. I don't think I have any text books on this, and I dug out some old notes and thats not helping me. If I'm correct on this the AC voltage of the stator will not rise, although if the resistance of the stator load decreases the current will increase. Which will at some point burn the stator out. I think h2olawyer is correct in thinking that the RR is directly related to the life of the stator, since its the bottom line on how much current draw there will be.

When the load increases to the level that the regulator can not maintain its lowest regulated DC output voltage then the stator output AC voltage will rise in an attempt to bring the regulator back within its regulatory range

[Brian Moffet]

I'm fairly sure, although I can't find the proper theory behind this, that the voltage that the stator puts out is only related to RPM, windings, and magnetic field.

Power is basically what is produced by the stator, and the maximum power available is based on the RPM, the number of windings, the number of poles, the magnets, and how close the magnets are (basically defining the magnetic field, the amount of wire passing through that field, and the speed it passes through the field.)

The voltage is set by the regulator, and then you can use the P = IV equation to get the amount of current.  Draw more than that current and your voltage will go down (because power is a constant for a given RPM).

The maximum power than can be produced for a given generator is when the internal resistance in the stator is equal to the external resistance. ( http://en.wikipedia.org/wiki/Maximum_power_theorem )  That would also produce the most heat in the stator, since it has to absorb 1/2 that power internally, (most likely in the form of heat). When the external resistance becomes higher, more of the power is dissipated in the external resistance (it's in series with the internal resistance) so the actual heat absorption of the stator would drop. 

If you had the old buzzer type of regulator (they use a spring-tensioned electro-magnetic buzzer to open and close to keep a constant voltage) then the internal power would rise and fall according to the close and open of the regulator.  But those are really noisy and push a lot of electrical noise into the lines.

That's basically the physics I'm going by, and I admit it's been a while since I looked at this stuff.  I'm willing to have someone show me the error of my ways.

[Re-Vision]

Brian, I think we could gain some useful information if you and H2o swapped bikes for a season or two.
1. If H2o's bike fails its probably H2o's fault.
2. If Brians bike fails it surely will be something H2o has done to it.
3. If both bikes fail then it clearly indicates H2o as the likely source of failures
4. If neither one fails then this would point to Brians doing the right thing and the outside chance that H2o's original bike is a lemon.  BDC

[Re-Vision]

Brian, believe you are correct in all you say at 19:03 if applied to a non-regulated system or a system thats operated within its design parameters (22 Amps).  I'm not certain that everything I've said is correct but I was applying it to a system that has problems in regulation due to phase resistances or excessive fused loads.   BDC