Something up with lead-acid

[Bkr2]

Hi there

I've had my veeery badly built bedini SG for a while now with 3 coil (1 main) setup and it worked allright for desulphation mainly. Recently I had several free hours on my hands and I rebuilt it with a little more effort and also changed it to the 2 main coil setup, it ran much better after that so I hooked it up to one of my Lead-acids that has been stuck on 13.15v top voltage and ran it for about 24 hours with no change at the end, it would charge up to 13.8v maybe and then drop to 13.15v in an hour but yesterday I discharged it down to the 11.5v with a small bulb and left it like that. I just unhooked it and checked to see 18.53v on the voltmeter and it's raising at a steady rate. Can anyone explain what is happening? Is it normal? Abnormal? Did I brake it? Did I make a super energy generating Lead-Acid battery? All input is appreciated.

[citfta]

Check your meter

Hi Bkr2,

The first thing to check is the battery in your meter. There have been several people fooled by their meter. On some digital meters when the battery starts to get weak then it starts to read a higher and higher voltage. If another meter or the same one after you replace the battery still shows the higher voltage then you have something very unusual that needs to be investigated more. Please report back and let us know what you find.

Carroll

[morpher44]

DC meters have trouble with AC

The Bedini circuit will produce AC currents, and thus when you measure
voltage with a DC digital meter, it can have trouble displaying the correct
value. It may jump around.
What you really need is an oscilloscope to see what sort of waveforms
are happening -- looking for that clasic "H" shaped pulsing.
An Analog DC meter will give more of an RMS value.

[garrettm4]

The Bedini circuit will produce AC currents, and thus when you measure
voltage with a DC digital meter, it can have trouble displaying the correct
value. It may jump around.
What you really need is an oscilloscope to see what sort of waveforms
are happening -- looking for that clasic "H" shaped pulsing.
An Analog DC meter will give more of an RMS value.

I don't know what kind of DVM you've been using... but a quality true-RMS meter (HP, Agilent, Keithley, Fluke & etc.) is much more accurate than an analog panel meter [1]. The reasons are many, but mainly have to do with input bandwidth, signal response time and crest factor accuracy. An analog meter uses a magnet and a small current though a coil to cause meter deflection, this causes the response time to be very slow [2] compared to a good DVM. Further, ripple is not read correctly with an analog panel meter due to bandwidth limitation of the deflection coil acting as a choke, thus HF ripple current does not accurately assist in the deflection of the meters arm used to indicate the signal amplitude. Another issue is parallax, the angle of your eye with reference to the arm and scale, which causes a further element of error. And finally, friction of the moving element causes errors as well [3]. I should point out that DVM's have their problems as well; gain error, DAC range sensitivity, input voltage burden / current burden and inherent random noise (although large sample averaging fixes the noise issue). In the end though, the uncertainty of a general measurement is less with a good DVM... but with cheap Chinese gear this may very well not be the case.

Further, the Bedini oscillator does NOT output AC! That's a fallacy, since you use a single diode attached to the coil to charge the battery. This would form impulses of DC - which, using Fourier's theorem, you could argue is AC with a DC offset.


Bkr2,

The battery should be tested in two ways, one measure the no load voltage, next measure the C20 rate load voltage. This will tell you the health of the battery, as sometimes an unloaded battery may check good but when loaded it doesn't perform up to expectation. The unusual voltage may be due to the battery actually being bad, to test, hook up an ammeter and a large potentiometer in series with the battery then measure the battery terminal voltage as you adjust load resistance of the pot. If voltage drops drastically when loaded or provides little to no current - it's definitely a bad battery.

As for weird battery experiences I have many! Most are from charging batteries from self built impulse chargers etc. One of the most strange battery experiences I've had was with a 4AH SLA of APC brand, commonly found in computer UPS. The weirdness was witnessed when discharging the battery, as the current output or source impedance oscillated dynamically - an incandescent bulb would go dim then bright at irregular intervals do to this phenomena. Another oddity was that during pulse charging some batteries refused to charge, their source impedance would rise exponentially. Some times to the point that the voltage across the battery would be 300 + volts. This of course is only possible with inductive impulse chargers, as the Lr time constant is what determines the output voltage, a high load resistance = a high output voltage and thus can self regulate the output VAs to charge sulfated batteries. But in certain cases, the battery refused to charge via this method while a DC constant current charge worked perfectly with the same battery. It may have something to do with off-gassing raising the internal impedance, hard to say.

On a side note, I think the point of Bedini's constant, dare say insescent, talk about the monopole oscillator, is to get people to try and figure out why more charge leaves a battery than enters into it. That is, when you measure the input current during charging and integrate it to get coulombs, then measure the discharge current, then integrate it to get coulombs, you have a coulombic efficiency greater than 100%. Which is impossible by standard chemistry and physics observations. For example NiCad has a coulombic efficiency of 66% which means you take the Amp-Hours and multiply it by the reciprocal of 66% (151%) to get the charge time needed for that many Amp-Hours. Or alternatively you can take the time you spent charging and multiply it by 66% for the length of time it will provide power during the discharge.

John's explanation is thus; that massless charge (i.e. charge carried by itself rather than an electron) enters into the battery along with "normal charge" carried by electrons. Sum both current's together, and we've overcome the coulombic efficiency problem of having exceeded 100%. Interestingly we only pay for the electrons and their associated interactions, however the "phi-dot" current is "free", like a continental breakfast at a hotel (you pay to stay but get free food in the morning). We can easily measure the current due to electron's carrying a certain amount of charge... BUT we CANNOT measure the massless "phi-dot" current "carrying" a certain amount of charge. I believe these are the fundamental points John has tried to make... but I think it all goes over most peoples heads.

On a final note, a battery during discharge (after being charged with something capable of producing a phi-dot current) does tell you about the phi-dot current but is an indirect measurement. As far as I know there is no known direct measurement method "publicly" available. Maybe John will read this and comment, which would be nice.

*Update: I do remember John saying to charge a capacitor with the phi-dot current, so you could technically make a measuring device using a sense coil measuring the magnetic field due to electron current and the capacitor as a charge integrator summing both currents. With this arrangement you would subtract the charge calculated by using the magnetic field measurement from the capacitors charge value and this should give you the "unmeasurable" charge quantity of the phi-dot current. So it seems there might be a way after all, haha. I would be curious how a resistive current measurement would fair vs. a hall effect vs. sense coil, on this arrangement? Well, seems I need to send John a letter to see if I'm in the right direction. If anyone has played with this or has any comments to offer send me a PM as I'm quite interested in testing this idea.

Regards,
Garrett


Notes:

[1] The best all around volt meter would be a thermal converting RMS meter like the HP 3403C, has 100MHz bandwidth with 10:1 crest factor capability and 10mv to 1000v full scale ranges.

[2] Due to the relatively large mass of the meters indicating arm and the relatively small force applied by the deflection coil.

[3] Any old school technician will tell you to lightly tap on the meter to get it to read correctly, this helps compensate for friction in the deflection arm. This of course for very small and sensitive measurements.

[ElectricMick]

Hi Bkr2,

The first thing to check is the battery in your meter.
Carroll

I took a dodgy batty to a bosch dealer and he said it was 52%. What does this mean? what are they measuring? - EMick

[citfta]

Hi ElectricMick,

Well as I wasn't there I can only guess what they did. My guess is they put some kind of load test on the battery and the tester showed the battery only had 52% of it's capacity left. Which would mean the battery was only capable of delivering about half the amperage it should have been able to deliver.

The other possibility is they had some way to measure the total capacity of the battery and found it would only hold about half as much charge as it should. In other words it could still deliver almost full amperage but for only half the time it should have been able to. Either way the battery is bad and needs to be replaced or rejuvenated. I hope this helps you understanding of batteries.

And by the way to the forum

Carroll