Electricaly challenged

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Richard Tool said:
So run incandescent bulbs with lights on all the time ( which one should do regardless) and standard battery and I will decrease the chances of a damaged alternator if I understand correctly, yes ?
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Well that is the general idea. Potentially better for alt heat buildup but downside is poor battery charging at lower rpm. I'm not convinced the alt is overally sensitive heat build up as it lives in a casing being splashed by primary chain oil and will always see heat from engine anyway.

If podtronic type reg recs were detrimental to alt when running lower consumption lights etc then we'd see loads of them failing and we do not. I run led headlight and brake light and recently replaced faulty zener with a shunt rec reg (typanium). Done 500 miles at speed without issues.
If alt does pack it in, I'll just declare the 45+yrs old device has served the bike well and replace it.
 
Tornado said:
I think the standard shunting type reg/rec units like the podtronics and used on nearly all modern bikes are fine with standard norton setup. Issues more likely as you make other changes like LEDs and LiPo batts. With LEDs etc you're lowering power loading and once batt is fully charged that excess alt output is shunted back to alt coils and makes heat. Like many things in life there needs to be a certain amount of balance to output vs consumption.
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If you go on some modern bike forum sites for like Triumph, Yamaha or Kawasaki or Suzuki you will find many complaints of burnt out alternators and r&r and how the fix is to go to a genuine Shindengen SH775 r&r .
 
HRD said:
Yes ,as you proclaim no expert ,so belief is greater than sound and rational explanation ? Your belief is yours to have .
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You could clarify what you “believe” is wrong with the regulators.

If you think that regulation by shunting the output sets these permanent magnet alternators on fire, then I think you should demonstrate that with some rational experiment.
 
Richard Tool said:
- I have had a Podtronics in my ES2 for many years with no issues- sealed battery as well . 6V dynamo so perhaps that makes a difference vs alternator - once again I am handicapped by my lack of electrical knowledge.
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The dynamo is different in that it’s regulated by restricting the current to the field winding.
 
Triton Thrasher said:
You could clarify what you “believe” is wrong with the regulators.

If you think that regulation by shunting the output sets these permanent magnet alternators on fire, then I think you should demonstrate that with some rational experiment.
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What I understand is that if the output of the alternator is not balanced against the load (when LED lighting instead of conventional lighting is used for example), the output of the alternator is shorted by the Podtronics unit, causing excessive heat in the stator.
A lot has been written on this subject on this forum by guys with more knowledge on this subject than I have.
 
Peter R said:
What I understand is that if the output of the alternator is not balanced against the load (when LED lighting instead of conventional lighting is used for example), the output of the alternator is shorted by the Podtronics unit, causing excessive heat in the stator.
A lot has been written on this subject on this forum by guys with more knowledge on this subject than I have.
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A lot has been written, generating more heat than light!
 
The cost of the SH 775 is no big deal - seems to be around $ 100. vs $60 ish for Podtronics unit . Can anyone tell me does it work with positive ground and original single phase alternator and also will it fit in battery tray area ?
 
It didn't fit in my battery area. I extended my rear footpeg/muffler mount up into the area in front of the rear shock and mounted it there. It does work with positive ground and it will work with the single phase alternator by just using the 2 wires instead of 3. Beware of fakes. I bought mine used from a snowmobile dealer way back when we started talking about the SH775.
 
Richard Tool said:
The cost of the SH 775 is no big deal - seems to be around $ 100. vs $60 ish for Podtronics unit . Can anyone tell me does it work with positive ground and original single phase alternator and also will it fit in battery tray area ?
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The $100 price point unit is likely a fake knock off. That will be a standard shunt type, same as podtronic except in a SH775 like casing. Genuine go for $150-$190 I believe. They are also quite large to find good fitment location on our bikes.

Again, I think it's overkill for the relatively low output stock alt makes.
 
HRD said:
If you go on some modern bike forum sites for like Triumph, Yamaha or Kawasaki or Suzuki you will find many complaints of burnt out alternators and r&r and how the fix is to go to a genuine Shindengen SH775 r&r .
Click to expand...
From about six years on TriumphRAT forums I've seen a few reports of overheated plastic connectors to alt and claims of failed R/R's but never any alt coils burned up. Stock r/r's are the lowly shunt type. Hundreds of thousands of bikes using these. Note the alts are also much higher output than stock commando. That's a pretty good track record to go with.
 
If you look at a pile of used Lucas stators at a swap meet, they all look like the potting compound has become discolored from heat.
 
batrider said:
If you look at a pile of used Lucas stators at a swap meet, they all look like the potting compound has become discolored from heat.
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How manyof these were being used with shunt regs? Normal zener is not shunting the alt coils.
 
OK where's the circuit schematic of what's inside a Pod regulator? I think it is pretty much equivalent to a rectifier and a transistor circuit on the DC side that conducts (or shunts) to ground over about 14V. I don't think it is shorting the alternator windings directly but could be wrong.
 
I personally prefer to describe the Podtronics, Tympanium, Pazon and PowerBox as ‘Short Type’ regulator/rectifiers.

They work by shorting out the alternator windings when charge is not required.


Using this way to describe them prevents confusion around shunting.
The original zener diode shunts it’s load to earth, but that is not the characteristic we are talking about here.
 
batrider said:
OK where's the circuit schematic of what's inside a Pod regulator? I think it is pretty much equivalent to a rectifier and a transistor circuit on the DC side that conducts (or shunts) to ground over about 14V. I don't think it is shorting the alternator windings directly but could be wrong.
Click to expand...

With the Zener, the shunted current has to go through the voltage drops across the rectifier, the the Zener and the alternator coils.

At each component, power in the form of heat, equivalent to the component’s voltage drop x the current has to be dissipated.

It makes sense that a reg that shunts the AC could have less heat to get rid of than one that includes the rectifying diodes in the shunt circuit. But it depends on exactly what components are in that there black box.

This guy did some tests.

There has been some forum discussion about the power consumption of Lucas alternators, i.e. how much effort does it take to rotate a rotor. Most thought it would be at maximum effort when the output leads are shorted together. However one lone voice declared that the drive power would be at minimum with leads shorted. To test the theory I set the frequency of my inverter to 17Hz (1000 RPM) and noted the output current of the inverter with no load, with a 1 Ohm load and with the stator leads shorted together.
The tests showed that minimum power is required with shorted leads. Not surprising then that most modern rec/regs work using this system as the following example shows:
http://mastercircuits.blogspot.co.uk/2010/05/motorcycle-voltage-regulator.html
I was surprised at how little difference there is between the no load and 1 ohm load values. If anyone is wondering why the no load values are so high don't forget that you have a set of rotor magnets trying to hang onto the stator poles
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batrider said:
OK where's the circuit schematic of what's inside a Pod regulator? I think it is pretty much equivalent to a rectifier and a transistor circuit on the DC side that conducts (or shunts) to ground over about 14V. I don't think it is shorting the alternator windings directly but could be wrong.
Click to expand...

I haven't seen a schematic either, but the general description of that type of regulator is that they use silicon controlled rectifiers (SCR's) to shunt the windings. They trigger on a cycle by cycle basis when the output gets to a set level. So yes, they "short" the stator for a portion of each cycle. It's not like a direct short circuit. The more modern versions use MOSFET transistors.

I've looked for replacements for the factory zener and found that a JAN1N3313RB comes close, Mil Spec temperature range, 14V +/- 5% 50 watt stud mount with a 1/4-28 stud. Still in production but nobody stocks them. DigiKey says you gotta buy 100 of them.
 
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