Cap Dump

[ibpointless2]

I really don't see any real cap dump circuits here so I decided to make a new thread on the topic.

A cap dump should be simple and very effective. A capacitor charges up to a certain voltage or point and then discharges through a load. Where i see using cap dumps is in the crystal cell. Crystal cell usually have a high resistance to them so charging capacitor would be idea and then have the capacitor dump into a load. It doesn't have to me a crystal cell it could be many things. Sure a monopole motor would be the best to go about this but i think we should look for a solid state way of doing this.

I've used a P.U.T before to do a cap dump and other types of SCR's. You can use a NPN without the base to do a avalanche of the semiconductor material. The problem is that none of them are perfect.

Here is a interesting link that does a cap dump into a motor. BEAM Circuits -- Zener-based type 1 SE


If anyone has idea's for cap dump feel free to share, we all can benefit.

[ibpointless2]

The main problem with semiconductor material is that they allow some small current to pass, and this is wasting power. The perfect cap dump uses a spark gap but that requires a high voltage to do. This is the problem i run into and i'm sure other have too. we need a component that doesn't exist. I wish they still made the 4 layer diode (Shockley diode). Four-Layer Diode
This diode seem about as close I could get but they don't make them anymore.

Or something...

I've thought about turning a capacitor into a switch. This would be ideal.

[forelle]

The main problem with semiconductor material is that they allow some small current to pass, and this is wasting power. The perfect cap dump uses a spark gap but that requires a high voltage to do. This is the problem i run into and i'm sure other have too. we need a component that doesn't exist. I wish they still made the 4 layer diode (Shockley diode). Four-Layer Diode
This diode seem about as close I could get but they don't make them anymore.

Or something...

I've thought about turning a capacitor into a switch. This would be ideal.

Hi ibointless2,
i didnt realise that you have allready opened a thread about cap dump.
I thought a GDT should work as a low potential spark gap,they are available from,i'm not sure,80v up to 1000v i think.
You dont have any experience with this type.
Thanks

[Floris]

Yes, A GDT works quite well, I have tried some but none go below 90V AFAIN. It makes a very simple circuit and therefore elegant. However, 90V into 12V battery is too high for my liking, JB suggests double the voltage of the charge battery. Could be a good setup for desulphation or a 36-48V battery bank. Good thing is there are no problems with SCR's latching with large caps as they are not needed.

[forelle]

Hello to all,
I would like to ask:the cap dump cicuit we are here talking about is for the same than the circuit with the FWBR,555 timmer,h11D1,2N3584(2N3055 works also?) cap,SCR 800V wich is allways seen with the trifiliar coil?
And how is it made when i have a 8 filiar coil?Is than 1 wire trigger,1wire power and 6 wires in the FWBR?Or to i need for each of the 6 wires a FWBR?
Thanks

[John_Koorn]

Hello to all,
I would like to ask:the cap dump cicuit we are here talking about is for the same than the circuit with the FWBR,555 timmer,h11D1,2N3584(2N3055 works also?) cap,SCR 800V wich is allways seen with the trifiliar coil?
And how is it made when i have a 8 filiar coil?Is than 1 wire trigger,1wire power and 6 wires in the FWBR?Or to i need for each of the 6 wires a FWBR?
Thanks

forelle,

yes, it is the same. There are many ways to dump the cap, the method you mentioned is one of them.

as for your 8 filar coil you will have one trigger, six power and one recovery winding which goes to the FWBR.

John K.

[RS_]

JK,

sorry to butt in here, but i would do it/have done it, with 1 trigger and 1 transistor, and 6 recovery/pickup strands each on a FWBR.....

and one could also fill up 2 different caps with 3 strands each, and pulse them both out at the same time into different battery's with 2 pulsers and the same timer

[forelle]

So there are many combinations.
I'm wondering why the method with the cap is better than the normal SSG where 1 wire for trigger and 7 wires for power and charging.

[Catrinisin]

I am also wondering why people do the cap dump at all. In a video I saw JB disconnect the cap dump circuit and connects the coil output directly to the battery and he says 'yeah you can hook it straight up too'. But he never says which is better or why.

Some questions:
1) Does the cap dump change the energy going to the battery from "negative" radiant energy into normal positive current?
2) What benefits are there to using a cap dump circuit?
3) Since there are so many different ways to go about it, which circuit type should I try first? I want to do once for a 3 filer coil (2 transistor) an 8 filter coil, and also a medium sized joule thief.

Thanks!
Chris

[hobbyrobotik]

Hi Chris,

see:
http://www.energyscienceforum.com/be...t-primary.html

[BobZilla]

Hi Chris,
I would add that people use cap dumps on different systems and different positions within the system too.

Sometimes they will use it at the charge side to re-gauge the output to positive. This is helpful if you need to take a back battery and put it on the front.

Other times you may want to hook it up to a generator coil(s) on a mechanical system to harvest normal energy, the cap is used to let the energy build up to a desired voltage and then dump it very rapidly to a battery. From what I have read you want about twice the voltage of the battery or bank that you are charging.

I have no experience with cap dumping personally but those are two uses that I have read about that other people configure.

[Catrinisin]

Thanks Bob,

This is exactly what I want from the sound of it. I saw min2oly's video with his snazzy looking cap dump box. Does anyone have a circuit diagram of that one?

[Catrinisin]

Okay I have some questions. I built an SCR/Zener cap dump and it seems to work fairly well. My first question is what size cap should I be using? I've tried 1000uF - 15000uF. The only difference I can see is that it takes longer to charge the higher capacity caps and thus reduces the dump frequency. Is there an optimal timing with the pulsed dumping I should shoot for? Is there more current going in with each dump with larger caps? Is that good or bad?

Next, what kind of voltage drop should I expect on the scope? I'm running on a 12v lead acid source, charging 12v lead acid. Zener is 16V. The voltage drop I see across the cap on the scope is only 5 volts. I expected the voltage to drop around 12-14 volts or so. I do see the stair step climb and then the dump, but only a 5 volt span total. Is this normal?

Thanks
Chris

[Tom C]

A 15000 uf 50 volt cap. and you want to dump at twice the battery voltage 25 or more volts. little batteries need a little cap bigger batteries a bigger cap. enough to move the ions. you will no itys right cause your battery will charge !!!

Tom C

[Catrinisin]

Thanks for the reply Tom. My largest cap is 15000 uf 50 V. That one dumps about once per second on this small two transistor energizer.

The battery is definitely charging, a lot faster than straight radiant too. I suppose I just have to run through some cycles to find what's best.

I'm still curious about the 5 volt voltage drop though. I was using a 12 V zener and the voltage drop across the cap was 3.5 volts. Now with a 16V zener, it's a 5 volt drop on the scope. How can I tell what voltage the cap is dumping at? I'm not that experienced with using a scope, but I do know how to read the output. It is showing 5 volts from top to bottom as I stated, but again how can I tell what voltage the cap is getting to before dumping?