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Author Topic: Cool joule ss/ssg  (Read 93234 times)
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This one started out as a pulse motor build,but took a left turn when i noticed the battery voltage climbing when it went into self oscillation.
http://www.youtube.com/watch?v=2fvLwjvTA60
   
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TinMan
So your running a load and very slowly charging a nicad battery with no additional input.....
Some folks call that  looping? Other folks say Its "loopy"!!

Better get out the rain coat just in case ..... ^-^

Thx
Chet
   

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Buy me a beer
Brad, that is very VERY cool, not just cool.

Chet, umbrella as well might be needed >:-)

Wasn't Steven doing something like this? I'm sure he will like this a lot, especially when I believe someone took a machine gun at him for his tests I also believe.

Nice instructive vid as usual Brad O0  the area of frequency is interesting, I find a lot happens between 3-8khz for some reason :-\

Mike 8)


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"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860

As a general rule, the most successful person in life is the person that has the best information.
   
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tinman,

Have you tried with a light blocking hood over the LED?

LEDs may also act as photoelectric cells.

>>Edit:

I was still watching your vid when I posted the above.

You answered my question by turning your shed inverter off causing the lights to go out.

I had one of these that ran for several months with no external power sources applied. I checked the same possible interactions you did.

What I determined was the extra energy was be added by me when I had to jostle or disconnect-reconnect the circuit or turn the lights on to check it each day to keep it on track to charge the battery vs. drain it.
   
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forgot.....


One LED is very unlikely to be a hidden source of charging power but if you go the route of other experimenters and 'load' your JT down with a huge array of LEDs you are actually just adding solar cell capacity as the charging source.

I bite my tongue when I see folks 'loading' their JT with huge LED arrays or seemingly useless diodes in the circuit in a well lit room. ;)

Glass diodes do a fairly good job acting like solar cells.

I had to play with mine every morning because the lights were out the previous night  C.C
   
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It's turtles all the way down
Don't forget that batteries can gain voltage capability in the short term by pulsed elimination of sulphation thus reducing internal impedance.

Also there is the battery warming effect. Tinmans increase is on the order of 2%. I suspect if left running until mostly desulphated, the voltage rise will then turn around.


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"Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy
   
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I just connected one of those not quite so white white LEDs from a garden lamp my wife told me to fix to an AA from the same light.

It lights (barely) and the battery voltage started to climb under the bench light after a few minutes. The LED puts out 1.7V without the battery connected and held close to the bench light.

ION,

Yes. Another tricky part to these battery circuits and why most folks fade away when they replace the battery with a cap. Of course, some well known folks just claim a battery and a cap don't work the same way. They are correct  ;) but not for the wild reasons given.
   
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Those batteries the "1.5 Volt rechargeable's"

I believe they were chosen to stay away from the Lead acid battery  " Issues/Anomolies" ?

thx
Chet
   
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I often see that effect, the power draw doesn't drop the supply battery much but the charge battery can build a voltage in its capacitance or something while under the charge of the spikes so the two batteries in series show a raised voltage. The LED won't draw any current below a certain voltage which may well be higher than the charge battery voltage and is in series with the charge battery so the spike is clipped by the LED and the battery get's the rest. Those AA's can hold a lot of Milli aH charge and if the supply one is in good condition and the charge battery not liking to take a charge the supply battery won't drop much but the charge battery will raise voltage quicker if it
has certain problems (higher internal resistance).

Cheers   
   

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What's most puzzling is how the circuit is
able to oscillate.  The scope waveshape is
that of the classic Blocking Oscillator but the
circuit diagram doesn't seem to support such
operation.

Any clues?


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For there is nothing hidden that will not be disclosed, and nothing concealed that will not be known or brought out into the open.
   
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Hi all
I would like to comment on some of the thoughts above,and also give the readings from the meters after the cool joule was running all night in the dark.
Total voltage is now 2.487
Run battery-1.222 volts,a drop of .006 volt's
Charge battery-1.259 volt's,a rise of .154 volt's--This was since the last time i measured the charge battery voltage alone.

Both these battery's are new-first timed used-straight out of the garden lights.

WW-One LED is very unlikely to be a hidden source of charging power but if you go the route of other experimenters and 'load' your JT down with a huge array of LEDs you are actually just adding solar cell capacity as the charging source.]

Not possable,as the current flow from the LED would be in the wrong direction to charge.I also have a diode on the collector that would stop current flow from the LED in that direction.The transistor would also be open when and if the current could flow in that direction.I think you will find that all ss system's would not be receiving a charge from the LED's,as the current flow is in the wrong direction-and also because the collector is open when the current from an LED array could flow.Even when the C-E junction is close-the positive charge would be flowing straight to the negative of the run battery-as the emitter on the npn is ground(or negative).So i cannot see any way that any number of LED's could be adding to the system?.

@ION-Don't forget that batteries can gain voltage capability in the short term by pulsed elimination of sulphation thus reducing internal impedance

As i said above,the battery's are new-first time used.They are also nicad's-so no desulphation taking place here,only the conversion of potassium hydroxide to cadmium hydroxide as the battery discharges-so no sulphide involved here.

@WW-Yes. Another tricky part to these battery circuits and why most folks fade away when they replace the battery with a cap. Of course, some well known folks just claim a battery and a cap don't work the same way. They are correct  but not for the wild reasons given.

The only problem i see is that although a cap;s parallel resistance is low(like a batteries),the series resistance is very high.As we have the batteries hooked in series,this may be a problem when switching to cap's-as the circuits resistance will rise?.I do intend on switching to cap's,but i will use super caps to try and bring the series resistance down as far as we can.There is also that lose you get when charging one cap with another-i believed Ex and poynt mentioned this a couple of time's.

I have been playing around with pulse motors and ss system's for many years now,and am well aware of battery effect's that can take place when using SLA's.I also see nothing special about this simple oscillator,other than i have never seen this happen with nicad's.The thing to remember here is that we dont have high voltage spike's charging a battery-the voltage the charge battery is receiving is only 2.42 volt's(after the LED has had it's bite at the voltage available).
The reason i like using nicad's is because to gain voltage when charging,you must convert one chemical back to another.The amount of this change determines the charge within the battery-unlike SLA's where you can have a surface charge form on the plate's them self.
   
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What's most puzzling is how the circuit is
able to oscillate.  The scope waveshape is
that of the classic Blocking Oscillator but the
circuit diagram doesn't seem to support such
operation.

Any clues?
I am also a bit stumped as to how the circuit still oscillates with the two coil's(run/trigger)so far apart?.-as seen in the video.
   
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Not possable,as the current flow from the LED would be in the wrong direction to charge.I also have a diode on the collector that would stop current flow from the LED in that direction.The transistor would also be open when and if the current could flow in that direction.I think you will find that all ss system's would not be receiving a charge from the LED's,as the current flow is in the wrong direction-and also because the collector is open when the current from an LED array could flow.Even when the C-E junction is close-the positive charge would be flowing straight to the negative of the run battery-as the emitter on the npn is ground(or negative).So i cannot see any way that any number of LED's could be adding to the system?.

If you have a chance, please post a schematic, in any form you wish.

I'm sure all SS systems would not be prone to charging from the LED in the circuit but the typical blocking oscillator is prone to that function even when a diode is in series with the LED, especially then, if that diode is a typical silicon glass bodied switching type and that diode is polarized the same as the LED.

The diode and LED act like two solar cells in series.


The output polarity of an LED in solar cell mode is the same as in LED mode. Where you apply negative to light the LED is where the output of the LED is negative when shining light on the LED. So, it is quite possible to charge a battery with one component, the LED. The same simple circuit with a diode added to it to make sure current only flows one direction will apply an even higher voltage when charging the battery under a light source.
   
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Below is the schematic for the circuit.As you can see,it is just the ss ssg circuit with an extra LED on the charge output-along with high ohm coil's.Also note that there is no way for any current from any number of LED's to pass back to either of the batteries.
Edit-this is an air core system,so please pay no attention to the core depicted in the schematic.
« Last Edit: 2013-04-29, 14:38:59 by tinman »
   
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Hi have just found out that even though all these solar lights are the same kind,some have nicad's and some have Ni MH batteries in them.I havnt worked with metal hydride batteries befor,so im not aware of how there chemical makeup reacts with pulse charging-but we will find out shortly.
   
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Thanks for the schematic, Tinman.

  Very interesting -- and reminiscent of earlier circuits in some ways... 

   Can you check the Frequency of the oscillation?  Is it 50 Hz (Oz)?
Or is there a 50 Hz "carrier" along with higher-frequencies?
   
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Thanks for the posted circuit.

I'll back out to leave you to your excellent work. Just keep in-mind that an LED as a source or sink has the same polarity.

WW
   
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Hi WW
I dont know yet if there is anything in this,but i am doing a rundown test on the first charged battery now-along side a battery that was charged by conventional means.I do know that the LED has the same polarity when used as a source or sink-but the current flow as a source is opposite to that of it being used as a sink.The circuit is just the berdini ss ssg circuit,but with high ohm coil's,an LED and NiMh or nicad batteries.But the ability to remove what is the trigger coil away from the drive coil and still have it oscillate is the bit that has me stumped?.I can move it out of magnetic range-and it still runs-Mmm?.
   
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Hi PhysicsProf
The frequency is 5.856kHz.There is no sign of the 50Hz of mains power within the signal.I also switched of the grid power to the shed via the isolation switch in the video,so as to eliminate that chance-but the battery still kept charging.
   
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Tinman

That's what interests me as well.  I've built a similar circuit in the past and I could get self oscillation under certain conditions, but the coils had to be in close proximity, however I've never tried it with those beefy looking audio transistors you have.

As far as the voltage climb, that's the old debate. One battery has a different voltage current slope then the other charged battery, so since the current draw is so small you won't see it change in a day or few days, but the other since its almost drained, will show a faster voltage change.
The old trap that "Bedazzled" fell into!  lol

EM
   
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Hi WW
...the ability to remove what is the trigger coil away from the drive coil and still have it oscillate is the bit that has me stumped?.I can move it out of magnetic range-and it still runs-Mmm?.

With any circuit involving long lead lengths and frequencies in and above the kHz range there is a strong possibility that unexpected capacitance is also involved.

A good test of this idea would be to rearrange the wiring so the base-emitter circuit leads are at right angles to the collector-emitter circuit or create more separation between wires running parallel to one another.
   
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What's also interesting, there is no DC bias? 
   
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It's turtles all the way down
Quote
But the ability to remove what is the trigger coil away from the drive coil and still have it oscillate is the bit that has me stumped?.I can move it out of magnetic range-and it still runs-Mmm?.

The single FET oscillator circuit I posted a while back would work with 4 feet or more separation....those em waves are not afraid to travel.


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"Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy
   
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Have aether? we'll travel.   :D
   
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Have aether? we'll travel.   :D
Not sure what we have just yet EM lol.The same run battery is still going,and second charge battery is in the unit.The first charged battery ran the garden light for 3h50m-so about 40 minutes short of a battery charged conventionally O0-keeping in mind that we only used .003 volts from the run battery to charge it ^-^.
The run battery has drooped .007 of a volt from start voltage two days ago-so not doing to bad,and running the LED aswell-although not very bright.
   
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