Please check diagram and confirm for me

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worntorn said:
According to John, the PODtronics does the same job as the Zener, it just dumps excess alternator energy to ground which creates heat.

So here I was briefly thinking I had increased the RWHP of my Commando by adding the PODtronics but it turns out it is unchanged. Oh well, it still feels pretty good!

Glen
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I've been lied to! :cry: It's like when you find out Santa Claus is just your dad in a red suit! Or that there really weren't people stuck on the island in Gilligan's Island.
 
Nater_Potater wrote:

"Lucas; yes. Podtronics; no. As said in an earlier post, the Lucas system can be compared to riding around with the throttle wide open, and using your brakes to control the speed. In the case of the Podtronics, the internals pass controlled bits of the incoming power from the stator, thus only letting enough current into the system to maintain the proper voltage. Theoretically, if the battery voltage was up where it should be, no power would make it through the regulator. I have mine mounted next to the battery, and it barely gets above ambient, whereas the original system did a respectable job of warming the z-plate unless all the lights were on."

Worntorn wrote:

"According to John, the PODtronics does the same job as the Zener, it just dumps excess alternator energy to ground which creates heat."

Something is amiss here .... If Worntorn is right ( It is hard to argue he is wrong when he is quoting an owner of Podtronics), then dumping energy to ground creates heat which must make the Podtronics unit warm. However, Nater reports his Podtronic unit barely gets above ambient, which implies the unit works as Nater describes it.

When I bought my Podtronic unit I was under the impression it worked as Nater describes. I do not remember where I got that info, but I felt it was reliable. I have not yet cranked up my Atlas with the Podtronics so I cannot add my own experience to the question of operating temperature. Anyone else have a Podtronics? Does it get warm unless all the lights are on? If "yes", then it works per Worntorn, if "no", then it must work per Nater.

Slick
 
I have found only two regulators avaiable that will unload the alternator when the system voltage is reached. Neither of them are sold for British bikes.

So why do you need to protect the alternator from shorted wiring when the regulator normally shunts to ground anyway?

In a normally operating system if the alternator is rated at 180 watts at 3000 rpm then it is always producing 180 watts at 3000 rpm, regardless of the output voltage.

Normally that 180 watts is distributed between charging the battery, providing light and making sparks. Some of it is wasted as heat in the regulator, stator winding and other electrical items.

Now if the alternator output is shorted the alternator is still producing 180 watts but the only outlet is producing heat in the stator and wiring up to the short and heating the rectifier bridge.

If the output is only partially shorted and say the voltage is held down to 6 volts then the currant in the stator and wires up to the short will be 30 amps.

A 15 amp fuse will do. Jim
 
Jim,
On those regulators that unload where does the excess current produced by the alternator go? Is it possible that they some how stop the alternator from producing current?

Pete
 
Way back in the dark ages, before Zener diodes and electronic wizardry, I unloaded my stator by installing a toggle switch in one of the stator wires (which went to the Lucas rectifier). The excess energy went nowhere because there was no excess energy .... with an open circuit in the stator windings, no energy was created. I monitored my battery condition by observing the brightness of the lights, then flipped the switch on as needed. I did this to prevent battery boil over .... not good for the chrome... lost primary chain cover and left silencer ... once was enough. Having a magneto ignition made this a practical system.

This simple control circuit is easily replicated with modern electronics. The stator windings can be open circuited on a cyclical basis, with a duty cycle as required to maintain proper battery voltage. I would be embarrassed as an engineer if I were to design a voltage regulator that failed to work in this way.

Slick
 
comnoz said:
I have found only two regulators avaiable that will unload the alternator when the system voltage is reached. Neither of them are sold for British bikes.

So why do you need to protect the alternator from shorted wiring when the regulator normally shunts to ground anyway?

In a normally operating system if the alternator is rated at 180 watts at 3000 rpm then it is always producing 180 watts at 3000 rpm, regardless of the output voltage.

Normally that 180 watts is distributed between charging the battery, providing light and making sparks. Some of it is wasted as heat in the regulator, stator winding and other electrical items.

Now if the alternator output is shorted the alternator is still producing 180 watts but the only outlet is producing heat in the stator and wiring up to the short and heating the rectifier bridge.

If the output is only partially shorted and say the voltage is held down to 6 volts then the currant in the stator and wires up to the short will be 30 amps.

A 15 amp fuse will do. Jim
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Isn't the rm23 quite a bit less than 180 watts at 3,000? The OP has the 120 watt Max rm 21, so I'm guessing might do around 80 or 90 watts at 3000. On the other hand, it could work with a 10 amp fuse, so it might be capable of burning that in a short out situation?

Only one way to find out, who wants to provide the guinea pig? :mrgreen:

Glen
 
Slick,

Guess it's cheaper to produce a regulator that shunts the excess than produce a control circuit to switch the windings "off" and "on"?

Pete
 
texasSlick said:
Nater_Potater wrote:

"Lucas; yes. Podtronics; no. As said in an earlier post, the Lucas system can be compared to riding around with the throttle wide open, and using your brakes to control the speed. In the case of the Podtronics, the internals pass controlled bits of the incoming power from the stator, thus only letting enough current into the system to maintain the proper voltage. Theoretically, if the battery voltage was up where it should be, no power would make it through the regulator. I have mine mounted next to the battery, and it barely gets above ambient, whereas the original system did a respectable job of warming the z-plate unless all the lights were on."

Worntorn wrote:

"According to John, the PODtronics does the same job as the Zener, it just dumps excess alternator energy to ground which creates heat."

Something is amiss here .... If Worntorn is right ( It is hard to argue he is wrong when he is quoting an owner of Podtronics), then dumping energy to ground creates heat which must make the Podtronics unit warm. However, Nater reports his Podtronic unit barely gets above ambient, which implies the unit works as Nater describes it.

When I bought my Podtronic unit I was under the impression it worked as Nater describes. I do not remember where I got that info, but I felt it was reliable. I have not yet cranked up my Atlas with the Podtronics so I cannot add my own experience to the question of operating temperature. Anyone else have a Podtronics? Does it get warm unless all the lights are on? If "yes", then it works per Worntorn, if "no", then it must work per Nater.

Slick
Click to expand...

Slick, I suppose those cooling fins are on there for a reason. If the alternator output is only slightly above what the system load demands, there won't be much warmth in the reg. My 200 watt Pod on the project bike is housed in the tail section behind the seat(not recommended) It does get a bit warm once the battery is fully charged, especially if the lights are left off. You can still put your hand on it, but it is a good hand warmer.

Glen
 
Deets55 said:
Jim,
On those regulators that unload where does the excess current produced by the alternator go? Is it possible that they some how stop the alternator from producing current?

Pete
Click to expand...

The circuit just goes open. It is known as a series regulator. It is used on a couple Suzuki models and there is an aftermarket unit available for a HD.

The voltage in the stator can go up in the 220 volt range but no power is wasted heating things.
 
worntorn said:
Slick, I suppose those cooling fins are on there for a reason. If the alternator output is only slightly above what the system load demands, there won't be much warmth in the reg. My 200 watt Pod on the project bike is housed in the tail section behind the seat(not recommended) It does get a bit warm once the battery is fully charged, especially if the lights are left off. You can still put your hand on it, but it is a good hand warmer.

Glen
Click to expand...

Agreed! If the alt output is just a bit more than the load, there will not be much warmth. OK ... so you are cruising down the interstate with no lights on, your ignition taking .... what? 5 amps? That is 60 watts, leaving 120 watts with a 180 watt stator (a 200 watt stator is more favorable to my case). If all 120 are being shunted to ground, that is more than the heat generated by a 100 watt light bulb. I would expect more than just "warm" ..... I would think the Pod would get dam hot!

I am not disputing what you have been told. I will be disappointed to learn I bought a Pod that is no more energy efficient than a Zener. Then there is Nater... telling us his does not get more than warm ..... It all leaves me wondering.......WTF!

Wish I could crank up the old girl (actually, I think of the old Atlas as "the Big Feller") and report my own experience.

BTW .... my Pod unit does not have much in the way of cooling fins.... just some ribs in an aluminum extruding.

Slick
 
texasSlick said:
worntorn said:
Slick, I suppose those cooling fins are on there for a reason. If the alternator output is only slightly above what the system load demands, there won't be much warmth in the reg. My 200 watt Pod on the project bike is housed in the tail section behind the seat(not recommended) It does get a bit warm once the battery is fully charged, especially if the lights are left off. You can still put your hand on it, but it is a good hand warmer.

Glen
Click to expand...

Agreed! If the alt output is just a bit more than the load, there will not be much warmth. OK ... so you are cruising down the interstate with no lights on, your ignition taking .... what? 5 amps? That is 60 watts, leaving 120 watts with a 180 watt stator (a 200 watt stator is more favorable to my case). If all 120 are being shunted to ground, that is more than the heat generated by a 100 watt light bulb. I would expect more than just "warm" ..... I would think the Pod would get dam hot!

I am not disputing what you have been told. I will be disappointed to learn I bought a Pod that is no more energy efficient than a Zener. Then there is Nater... telling us his does not get more than warm ..... It all leaves me wondering.......WTF!

Wish I could crank up the old girl (actually, I think of the old Atlas as "the Big Feller") and report my own experience.
BTW .... my Pod unit does not have much in the way of cooling fins.... just some ribs in an aluminum extruding.
u
Slick
Click to expand...

At 70 MPH that bike just balances the load of ignition draw, lights and heated vest. Lights and heated vest are 90 watts, so that is the excess which the Pod had to emit as heat. It is quite a bit, however the aluminium cooling fins transmit heat to the surrounding area much better than glass does, so the surface does not get hot like a light bulb. On top of that, although the tailpiece that the Pod is in is not open, it is made of thin aluminium sheeting, so makes for an effective radiator/heat sink. Cool air is flowing over the surface of the tailpiece/cowl as the bike moves along, so this is pulling the heat away. I might not have gotten away with this installation if the Tailpiece was made of fibreglass.

I rode without headlight off as an experiment to see how hot the POD would get. At all other times I ride with the headlight on, so excess power is only about 40 watts when cruising at 70 mph.

In the instructions that come with an Alton, Paul Hamon advises to always have the headlight on when the bike is running.
Aside from traffic safety, this reduces the heat load on the regulator. The regulators that Alton supplies are not PODtronics, and are said to be more prone to failure than the PODtronics units. According to Bob Kizer, of the many thousands of PODtronics regs sold, he only had one that failed. This was a lowly 120 watt rated PODtronics and it was installed on a Gold star with an after market 200 watt magdyno, so an expected failure.

Glen



Glen
 
Per Comnoz's explanation that the Podtronics is a series regulator, it begins to make more sense. Everything can be resolved .... sort of.

Series regulators do not unload (switch ON / OFF) the energy source. Thus no conflict with Jim's statements.

Series regulators are more efficient than the Zener shunt regulators we are familiar with as fitted to early Nortons. Thus much less heating. Thus no conflict with Nater's observations.

Series regulators do contain a Zener for voltage reference. The Zener controls a series pass transistor which controls the load (adds or subtracts resistance, sort of like turning a water valve to regulate flow). Thus the explanation given to Worntorn that the load is controlled by a Zener is true, but somewhat misleading. The Zener is not dumping the energy to earth as in the old Nortons, and thus there is no excessive heat.

Series regulators are indeed cheaper than switching ON / OFF (much fewer component count).

Now to find that misleading source that convinced me the Podtronics worked as a switching regulator.

I hope everyone sleeps better now.

Slick
 
I believe Jim was referring to a couple of other regs as series regulators, not the PODtronics.
John Healey explained it simply as the Pod is "just like a Zener" in that it dumps the excess power to ground.

Glen
 
worntorn said:
I believe Jim was referring to a couple of other regs as series regulators, not the PODtronics.
John Healey explained it simply as the Pod is "just like a Zener" in that it dumps the excess power to ground.

Glen
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Yes, A Podtronics is a shunt regulator.
It shunts the excess voltage just like a Zener.

A series regulator is the other choice for a PM alternator. It is rarely seen and a lot more expensive. Jim

For some deeper reading here is a link.

http://www.academia.edu/1110946/AC_seri ... generators
 
I seem to remember having a similar discussion on this topic some time back and came to the conclusion from emails with POD and off line discussions with Jim that the PODtronics is a shunt regulator and not series. I believe that the POD unit does its shunting on the A/C side by triac switching in the bridge rectifier circuit not on the rectified DC side as in a standard zener version.
I have disembowelled a regulator that was not a POD but looked very similar and that is how it worked.
There would be less heat generated in doing it on the A/C side of the bridge.
Also with the Alternator coil they are current limited by their design nature and will not put out infinite current when shorted.
In fact when they are shorted then the maximum designed current is then drawn at near 0 volts, so do the maths and see what the dissipated power at 0 or near 0 volts would be.

As for series regulators they would have to be a special design to accommodate the back EMF generated when the alternator coils are being switched/open circuited. This switching may also be at some 10's of Khz's.
Just have a think of when the points open on an ignition coil the rapid collapsing magnetic field causes a high induced voltage.

Hey but I'm happy to be wrong but that's what I deduced from my investigations

Please check diagram and confirm for me

Here is the disembowelled unit you can see two diodes and two scr's on the circuit board. This form the bridge rectifier and regulation all in one
 
comnoz said:
joeboomer999 said:
ok version 3.2 :) look good?

Please check diagram and confirm for me


Pete, that's the plan the lights will be on a totally isolated circuit including fuse. because of this im really only looking at the run curcuit right now as it will be easy to implement the other later.
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That's how I would do it. Jim
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Hi Jim,

I revive this thread because of the actual Problem of Piero. I have this fuse constellation on all of my bikes (no problem yet). But I am in doubt now. What would happen when the alternator side fuse would blow. The engine would still run, wouldn't it ?

Thanks !

Ralf
 
Ralf,

Your bike will run until the battery discharges to a point where it can not supply your ignition with enough power. The fuse is there to stop a dead short to ground and frying your wires and/ or bike.

Pete
 
Deets55 said:
Ralf,

Your bike will run until the battery discharges to a point where it can not supply your ignition with enough power. The fuse is there to stop a dead short to ground and frying your wires and/ or bike.

Pete
Click to expand...

That's what I supposed. But in case of a major fault in the alternator circuit like it happend to Piero it would not prevent this huge damage. If you have only one fuse, the engine would stop and the damage could possibly be avoided. But with the second fuse you can see where the fault is. I have a 30A fuse on the alternator side and a 20A on the ignition switch side. So I hope the smaller fuse will blow first.

crankshaft-play-end-and-maximum-tolerance-t24695.html#p325140
 
Deets55 said:
Glen,
I was thinking just the opposite. With the fuse where it is now, if a short happened the regulator would keep putting current into a shorted circuit. My bike has the key up front by the instruments, that's a long piece of wire where a short can happen. I guess the best thing would be to just fuse the regulator wire before it gets into the system. I believe cars use a fusible link.

Pete
Click to expand...

"fuse the regulator wire before it gets into the system". That is what I did on my Atlas when I installed a Podtronics, for the reason you cited.

Slick
 
Ralf,

I personally do not think that Piero's problem was an electrical issue. I believe that there was some sort of mechanical failure. IMHO a alternator such as the ones on our Norton's will not over heat and explode if the output leads are left unconnected (i.e. blown fuse) even after the rectifier. I think they would spin merry along with no problem. If there was a short the wire sizes are small enough that they would fail long before the alternator windings would catch fire. Take a look at the bolts that hold the alternator coils in place, something locked up and tried to rotate the whole unit. This is just my opinion, I could be way off base.

Pete
 
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