More charging info

Great discussion!

I run a 3 phase with, I think, is a Podtronics or clone (it's been so long I forget) and a Spark Brite voltage monitor light. I've got a Halogen headlamp which I run all the time. Even at relatively low RPM the Sparkbrite goes green quickly as I pull away from a traffic light. My only complaint is the regulator does draw when the bike is not running so I have to pull the fuse if I'm not able to ride for several weeks.

If I have to get into the system for any reason I intend to replace the regulator with a Shindengen but right now it's a don't mess with success situation.
 
Peter R said:
If i understand correctly, the Podtronics regulator and the likes regulate by shorting the alternator output to ground, which may results in excessive heat to the stator.
However, to my knowledge, does not the old style zener diode do the same ?
Am I missing something ? Hope somebody with more knowledge on this subject can enlighten me
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This was my understanding too for the longest time and it is incorrect.
The original system shunts excess power to ground. The alternator is designed for this, it just makes full power always(varies with rpm).
This makes the stator get a bit warm
Shorting regs work differently .
They short the two AC legs to each other once the system is at threshold voltage. This makes the stator get much warmer.
How much warmer depends on the load inbalance.
If you reduce load (leds) and change to a higher output stator, the load imbalance is quite great.
If the electrical load is close to the alt output, then the shorted out condition does not occur for very long, if at all.
That would be similar to an original bike, RM21, owner does away with the stock rectifier +zeners, installs a Pod. Many of these have been done and most work fine.
It was JeanDR's testing that brought these differences to light. Jeandr is an electrical engineer, old bike enthusiast and member of this site
Grant gives a great explanation of all of this on his site.
He also has Jean's info there
Glen
 
Just looking at the Tri-Spark MOSFET reg/rec compared to the Pod the size alone speaks for itself. If you watch the video on the following web page you will learn that the Tri-Spark does shut off AC input when not needed:

www.trispark.com.au

Voltage Rectifier Regulator

MOSFET 20 Amp Voltage Rectifier Regulator - Tri-Spark
www.trispark.com.au www.trispark.com.au

I'll admit that the reference is a bit under stated, but it is there.

In this thread there are references to static current drain. From my Air Force radar electrical training I learned that diodes have a front to back resistance; when measured you look for a minimum of 10:1 front to back ratio. Even under high spec circumstances this means that static current draw is unavoidable; for this reason I make a harness that isolates the charging system from the battery when the key is in my pocket; the first functional key position is for ignition, charging system and e-start, if present, only, no lights. When the key is in the off/take-out position nothing is being drawn from the battery. I might be wrong, but I think later Nortons have a similar scheme.

Best.
 
If shorting of the alt output leads and temp increase of stator is a big issue, we'd see huge numbers of failures as these reg/recs have been in use on our bike for decades and in larger numbers.
There was an old post somewhere that linked to a test of how much heat is made on the stator during operation with output leads shorted. It was negligible , something like 50 Cel after a long period of time. The primary case/oil runs hotter than that at operating temps.
 
Tornado said:
If shorting of the alt output leads and temp increase of stator is a big issue, we'd see huge numbers of failures as these reg/recs have been in use on our bike for decades and in larger numbers.
There was an old post somewhere that linked to a test of how much heat is made on the stator during operation with output leads shorted. It was negligible , something like 50 Cel after a long period of time. The primary case/oil runs hotter than that at operating temps.
Click to expand...
Open the link in my last post and see the test results.

Best.
 
Tornado said:
If shorting of the alt output leads and temp increase of stator is a big issue, we'd see huge numbers of failures as these reg/recs have been in use on our bike for decades and in larger numbers.
Click to expand...

The shorting/shunt regulator is by far the most common system used in the world. I don't know if any other vehicles except Brit iron used zeners?

Tornado said:
There was an old post somewhere that linked to a test of how much heat is made on the stator during operation with output leads shorted. It was negligible , something like 50 Cel after a long period of time.
Click to expand...

I disagree. There are pics on the web of stators that have experienced meltdown due to shorts.
 
RoadScholar said:
Open the link in my last post and see the test results.

Best.
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Yes that's showing how the MOSFET compared to other POD like RR, both temp and output wise. I was referring to actual heating of the stator tests that i've read on this site somewhere in past, unable to locate it now but results were the temp rise in stator was not enough to worry about using the shorting type regs. MOSFET is also shorting type, but it just does a better job on holding output volts in better range, making less heat with its own package and is physically smaller. All great things.
 
I wish that Grant Tiller was still around here. The conclusions postulated in his much quoted web article are based on bad science. Jean's tests were with a power transformer substituted for the alternator. They are NOT the same thing.

Some day I'm gonna do a proper test on a real motorcycle and publish the results.
 
Tornado said:
If shorting of the alt output leads and temp increase of stator is a big issue, we'd see huge numbers of failures as these reg/recs have been in use on our bike for decades and in larger numbers.
There was an old post somewhere that linked to a test of how much heat is made on the stator during operation with output leads shorted. It was negligible , something like 50 Cel after a long period of time. The primary case/oil runs hotter than that at operating temps.
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Grant is seeing more and more stators that have been overcooked. It's really only an issue when the load is light vs output, and even then only after many heat cycles.

Glen
 
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maylar said:
The shorting/shunt regulator is by far the most common system used in the world. I don't know if any other vehicles except Brit iron used zeners?



I disagree. There are pics on the web of stators that have experienced meltdown due to shorts.
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How do we know such melt downs were from the stators being over heated from the Reg/Rec and not just standard engine heat cycling over the decades leading to winding insulation breakdown?
As you've said, these shunting regs are in very wide spread use. We should be seeing constant,repeatable failures, within a couple of seasons of use on our old bikes if the problem was solely the shunting heat.
 
worntorn said:
Schwany, if the voltage draw down at idle did turn out to be an issue at some point, you could switch to a 2.6 ah lead acid an you should actually have a wee bit more battery storage.
If I have the correct specs, that is the rating with full charge at 14.4 volts. Down at 13.1 it's at 40% so that's around 1 ah.
A lead acid at 13.1 is fully charged plus, so you would have the full 2.6 ah available.
A 2.6 ah AGM is quite small and light. I found one about that size at 1.2 lbs whereas your Anti-Gravity is 15 ounces, not much difference.

Glen
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Thanks for the thoughts. All good points.

I had a 1.3ah AGM battery in it previously. Kind of whimpy, but functional. I wanted something small with more amps, and that's when I started looking at other options. I skipped the 2.6 ah batteries, and went looking for more amps. But yes those 2.6ah AGM batteries could be a good option should what I'm using go flat prematurely.

My bike is light weight as it is, so I don't gain that much from the weight savings, but it is a bonus. The fact that it fits where I put it, and the lights stay bright at idle is what I really like about it.

After I did the extended idle test. I went for a short 9 mile loop. I parked in the garage, and checked the battery at rest. It was at 14.14V. The bike has been parked for 4 days and the battery reads 13.9V. So far it seems to be doing alright with the discharging and over charging. Antigravity says don't let it discharge to under 11V. Since it stays around 12.9V lights On during extended idle I'm not that worried about it regardless of the science. If I get stuck in traffic revving the motor up a little at idle puts it over 13V instantly, so I'll pack my troubles in the old kit bag and hang in there with the little Antigravity battery for the time being.
 
Tornado said:
How do we know such melt downs were from the stators being over heated from the Reg/Rec and not just standard engine heat cycling over the decades leading to winding insulation breakdown?
As you've said, these shunting regs are in very wide spread use. We should be seeing constant,repeatable failures, within a couple of seasons of use on our old bikes if the problem was solely the shunting heat.
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Like I said in my post, back when we were all running halogen bulbs for our daytime running lights, our loads were pretty balanced, and we could justify 3-phase alternators, along with SCR shunt regulators.

Now that more and more folks are running LED's in every possible light source, current loads have dropped, likely in half, so now the regulators are spending a lot more time shunting excess generated power.

My 3-phase stator was showing distinct signs of heat stress when I took it out, and it was 30 years newer than the rest of the bike.

Personally, I don't have an axe to grind either way - run what you like. But an ounce of prevention is worth a pound of cure. Do with this info as you like.

FWIW
 
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Schwany said:
What do you see at the battery with a DVM at idle with the Shindengen?

I've used the PODtronics reg/rect that includes the battery eliminator feature, and the Tri-Spark MOSFET reg/rec with a lithium battery. Both of them undercharge at idle if they idle long enough. (That is a contradiction to a statement I made a while ago. I thought the MOSFET was providing over 14V at idle, but I hadn't done the long idle test when I said that. Have done the long idle test since, and tears welled up in my eyes when I saw the results. :)) Anyway voltage output ends up right around 12.9V with the LED lights on after 15 minutes idling with my single phase alternator. 13-13.1V with the lights off. I don't know if my alternator is a 10amp or 16amp. In my case 10 amp would be enough, but that is irrelevant. I did not run the test over 15 minutes to see if I'd lose enough voltage for the EI to quit. Edit: (Now that I think about it, I'm not sure that is possible unless I stall the motor at launch and the battery is dead.)

I'm tempted to try the Rick's Motorsports reg/rect, because it doesn't over charge with a 14.2V max output. The Tri-Spark MOSFET does overcharge according to the Shorai response and most of the lithium battery literature out there. Actually, I'm also tempted to try another reg/rect I found that has the same 14.2V max voltage output and costs a whopping $35US. That one might be a bike fire waiting to happen, but then again it might just be priced closer to actual cost.

Point is the MOSFET isn't really in spec. for lithium, so it won't buy you much other than I think it is a more robust part for a standard AGM, or lead acid battery.

Also starting to wonder if a PODtronics with the battery eliminator feature along with the lithium battery would be enough to sit at idle for long periods of time with the LED lights on and not have the EI die. I'd test that theory but the PODtronics lost an alternator leg after a short, and it's useless.
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baz said:
Yes pretty much the same as I understand it
But I assume with lower consumption LEDs etc there's a bit more heat for the stator to shed?
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Well, not really. The current in the stator may go through a lit headlight and other components and charge the battery. If demand is low, more of the current will be shunted by the Zener or the reg/rec box.

Switching the headlight off doesn’t make the alternator produce more current.
 
Tornado said:
How do we know such melt downs were from the stators being over heated from the Reg/Rec and not just standard engine heat cycling over the decades leading to winding insulation breakdown?
As you've said, these shunting regs are in very wide spread use. We should be seeing constant,repeatable failures, within a couple of seasons of use on our old bikes if the problem was solely the shunting heat.
Click to expand...
Some of the pics I've seen were from obvious electrical malfunctions, not just over heating but "melted".

What irks me is that they are often blamed for it being a consequence of the "shorting" reg/rect technology. Truth is that ANY rectifier, even the old OEM type, can fry a stator if one of the diodes fails shorted. I have no doubt that some toasted stators were connected to a shorting regulator when they failed, but I refuse to believe that the device was working normally and not defective.
 
Triton Thrasher said:
Switching the headlight off doesn’t make the alternator produce more current.
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I only posted because I was curious to know if the Shindengen reg/rect on Fast Eddies bike meets the Shorai idle time standard that gets mentioned over and over again. The rest of my post is babble.

Motor idling: Switching the lights Off makes the voltage reading on my DMV increase, switching the lights On makes it decrease. I really don't think at all about what the alternator is doing. My point in using the word alternator was I have no idea exactly which stator (alternator) I have other than it is 2 wire single phase. The science of the electronics is not my thing, so I avoid it if at all possible. Thanks
 
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Triton Thrasher said:
Switching the headlight off doesn’t make the alternator produce more current.
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True, but while the output is the same more of the output is turned into heat, heat is not your friend.

Another, not uncommon, reason for melted stators is rubbing by the rotor, usually at the 3 O'Clock position. If the rotor/stator isn't properly checked and set for radial clearance, if the primary chaincase isn't properly shimmed and tightened to the engine stator failure is inevitable. The resulting melt down will appear anyway the owner wants to present it; much easier to blame a "faulty" reg/rec than to man-up and take it on the chin. I am not saying that faulty reg/recs or grossly unbalanced output/load aren't right up there.

Best.
 
Schwany said:
I only posted because I was curious to know if the Shindengen reg/rect on Fast Eddies bike meets the Shorai idle time standard that gets mentioned over and over again. The rest of my post is babble.
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My bike isn’t running at present, but testing the charge at idle is pretty much at the bottom of my priority list. It spends so little time at idle, and based on G Tillers graph posted earlier, it’s supplying plenty of power at slow running rpm range, so output at idle it is utterly irrelevant to me.
 
Fast Eddie said:
My bike isn’t running at present, but testing the charge at idle is pretty much at the bottom of my priority list. It spends so little time at idle, and based on G Tillers graph posted earlier, it’s supplying plenty of power at slow running rpm range, so output at idle it is utterly irrelevant to me.
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So the Shindengen regulator is on the bike with the unsolved FCR dribble? I was not sure if your reference regarding using the Shindengen regulator was on a street or race only Norton.

I looked at a chart, but thought that was for amp output from various Lucas alternators at various RPM. I did not do any math to make the conversion to voltage out of the regulator to the battery. What was I thinking? I wasn't. :)
 
Schwany said:
So the Shindengen regulator is on the bike with the unsolved FCR dribble? I was not sure if your reference regarding using the Shindengen regulator was on a street or race only Norton.

I looked at a chart, but thought that was for amp output from various Lucas alternators at various RPM. I did not do any math to make the conversion to voltage out of the regulator to the battery. What was I thinking? I wasn't. :)
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Yes it’s the dribbler!

And yes, the chart only shows amps. I’d like to know the volts too but I’m not remotely knowledgable enough for that malarkey !

What I deduce from the graph is that in terms of amps, at tickover mine is producing very nearly as much as a stock (pre MK3) commando does at 4,000rpm. And at 1,700rpm mine is producing as much as a stock bike does at 6,000rpm.

So, I’m quite confident that the charging needs of the Shorai are covered, and that the Shindengen SH775 is the best / kindest way of handling surplus charge once the battery is charged fully.

AND I get to save 8.5lbs… what’s not to like ???
 
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maylar said:
Some day I'm gonna do a proper test on a real motorcycle and publish the results.
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"Someday" has a habit of never materialising, in my shed at least. As you appear to have some knowledge on this it would add greatly to the discussion if you could make those results available.
 
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