My Capacitor Discharge Circuit

[Zooty]

Hi all,

I came up with a simple cap discharge circuit that gives great results. It's basically a diac triggering a triac when the cap reaches 32v. I saw someone using a neon to trigger the triac but the voltage is much higher like that. The output of this circuit is very similar to the 555 timer setup Bedini uses on the trifilar monopole motors but is much simpler. The downside is i cannot control the voltage at which the cap is discharged. It is fixed at 32v due to the diac's breakdown voltage. If anyone can improve this, please go ahead. The charging results are great.

[xee2]

Hi all,

I came up with a simple cap discharge circuit that gives great results. It's basically a diac triggering a triac when the cap reaches 32v. I saw someone using a neon to trigger the triac but the voltage is much higher like that. The output of this circuit is very similar to the 555 timer setup Bedini uses on the trifilar monopole motors but is much simpler. The downside is i cannot control the voltage at which the cap is discharged. It is fixed at 32v due to the diac's breakdown voltage. If anyone can improve this, please go ahead. The charging results are great.

Thanks for sharing this circuit. Please post part numbers for the triac and diac. Kooler and I have been using neons to trigger an SCR as in following circuit.

circuit: http://www.overunity.com/index.php?a...0;attach=39943

[Zooty]

The Diac is a DB3 and the Triac is a BTA16-600B .. Both bought from maplin

[Jetijs]

Can't you just replace the diac with a zener diode of the desired voltage?

[Zooty]

Actually that is a good idea Jetijs. I must admit i am new to these components.

[nvisser]

Here is a circuit I used that works pretty good.
See post 15 on http://www.energeticforum.com/renewa...e-battery.html
I did find that the scr goes short circuit if I charge up a large cap like in your diagram.
I will definitely try your circuit . Can I use a scr in place of the triac. TYN612, 600v 12A
I bought some DB3`s a while ago. They are very small little blue components the size of a quarter watt resistor?

[xee2]

The Diac is a DB3 and the Triac is a BTA16-600B .. Both bought from maplin

Thanks. I have tried zeners and they work. But they fire at much lower voltages than their rating and they do not seem to fire at the same voltage all of the time.

[Zooty]

I find this circuit to be the most reliable of the ones i have tried in the past. It never gets stuck and it always discharges at the the diac breakdown voltage. When i used an scr, the one thing i noticed is if the cap was too small in capacity, the spike would overshoot the cap and cause the the scr to latch prematurely. I also found that scr's would frequently get stuck for no apparent reason. The other thing with this circuit is it discharges the cap on the negative side of the battery like in Bedini's 555 timer setup. According to some, this gives a better charging result. I will be doing cop tests soon.

@nvisser, i dont have enough experience to know if an scr would work in place of the triac but i dont see why not, the ones i have used have always gotten stuck but it may have been the ratting or something. The DB3's are the small blue things yes..

[Aaron]

neon trigger

I saw someone using a neon to trigger the triac but the voltage is much higher like that.

Zooty,

I did this long time ago. Discharge was 90v or whatever
the neon was at. I don't think it did very well for the battery at that
voltage and frequency. The cap I was charging was very low uf and it
made the gel cell I was charging have very fluffy voltage that kept
springing back up when I shorted the battery. It was like an electret
kind of effect. It would have been better for the battery if I used much
higher capacitance.

[xee2]

I find this circuit to be the most reliable of the ones i have tried in the past. It never gets stuck and it always discharges at the the diac breakdown voltage. When i used an scr, the one thing i noticed is if the cap was too small in capacity, the spike would overshoot the cap and cause the the scr to latch prematurely. I also found that scr's would frequently get stuck for no apparent reason. The other thing with this circuit is it discharges the cap on the negative side of the battery like in Bedini's 555 timer setup. According to some, this gives a better charging result. I will be doing cop tests soon.

@nvisser, i dont have enough experience to know if an scr would work in place of the triac but i dont see why not, the ones i have used have always gotten stuck but it may have been the ratting or something. The DB3's are the small blue things yes..

Great information, thanks. I do have problems with the SCR latching sometimes.

[Zooty]

Arron, i saw your youtube clip where you charge on the negative side with 60,000 uf via 555 and transistor. I am hoping to get similar results

[Aaron]

capacitance discharge

Hi Zooty,

Ok, that is the capstan motor I think. Cap charging and discharged
through that 555/h11d1 triggered transistor - originally I thought it
was a scr but in any case, the circuit is inverted and switched on the
negative.

I have seen a stronger charge on the battery with the inverted switching
on the negative.

Best results I ever had was large capacitance discharges every 2 seconds
with a mechanical switch.

[Zooty]

Aaron, did the mechanical switch make a huge difference? I saw bedini using a wheel/pulley/commutator system on one of his monopoles to dump his caps every 1.5 seconds or so. His caps were measuring around 16v over the charging battery and i could tell they were very big caps

[Zooty]

Today both the Dianc and Triac failed for some reason. Both components were short and the charge battery was dead as a dodo. Not as reliable as i thought.

[Aaron]

Dual Battery Charger

Aaron, did the mechanical switch make a huge difference? I saw bedini using a wheel/pulley/commutator system on one of his monopoles to dump his caps every 1.5 seconds or so. His caps were measuring around 16v over the charging battery and i could tell they were very big caps

Hi Zooty,

The mechanical switch made a difference. The system you describe is
essentially a version of the Dual Battery Charger. The first one I built was
about 9 years ago or so this exact size/spec:



The one with the really incredible results was actually with a 10 speed
wheel for the rotor and the coil was a 2000 turn trifilar charging a cap
bank of 198,000 uf (6 caps at 33,000 uf each) and I was charging to
2-3 volts above the battery voltage. I had the pulley sized to trigger the
switch every couple seconds.

It was with this system that the battery would self charge for up to an
hour after I turned it off and disconnected from the charging battery and
most of that charge was real charge that could power a load and not just
fluffy voltage static charge.