Tesla switch replication

[bugler]

Hello,

I want to replicate the Tesla switch as explained here: http://panaceauniversity.org/Chapter6.pdf starting at end of page 5.

On page 12 it is said that I need to use a 555 chip to make a 100-800hz pulsed circuit.



Could you please tell me what resistors and capacitors should I use to get 100-800hz in the output?

In another part it is explained that the 6 switches will be done with opto-isolators as in this image:



I need again the value of the resistor and also what transistor shoul be used.

And lately I am confused about where to use the 555. The 555 circuit is somehow switching on and off the 6 switches but I can't see where should I connect the 555 circuit in order to do that.

They say: "The output from Pin 3 needs to drive a very sharp switching combination such as a TC4420 FET driver connected
to IRF540 FETs." I don't get it. Are these transistoris the ones used in the previous image? How? Please help.

I would like to know if you think this is a useful thing to research and how many watts can I expect to get.

Thanks.

[Jetijs]

Please read this topic:
http://www.energeticforum.com/renewa...t=tesla+switch
I think this will be helpful
Thanks,
Jetijs

[InTheField]

Hello,

I want to replicate the Tesla switch as explained here: http://panaceauniversity.org/Chapter6.pdf starting at end of page 5.

On page 12 it is said that I need to use a 555 chip to make a 100-800hz pulsed circuit.



Could you please tell me what resistors and capacitors should I use to get 100-800hz in the output?

In another part it is explained that the 6 switches will be done with opto-isolators as in this image:



I need again the value of the resistor and also what transistor shoul be used.

And lately I am confused about where to use the 555. The 555 circuit is somehow switching on and off the 6 switches but I can't see where should I connect the 555 circuit in order to do that.

They say: "The output from Pin 3 needs to drive a very sharp switching combination such as a TC4420 FET driver connected
to IRF540 FETs." I don't get it. Are these transistoris the ones used in the previous image? How? Please help.

I would like to know if you think this is a useful thing to research and how many watts can I expect to get.

Thanks.

Hi, Pin 3 refers to Pin 3 of the 555 timer chip... I don't agree with the 555 circuit that is shown. To get approximately 100-800Hz with a 50-50% pulse using the 555 takes a little work. Leave the output (pin 3) to go directly to the transistors, relays, switches, whatever that you want to control. Setup the 555 with pin 8 & pin 4 connected to Vcc (+V), put R1 between pin 8 (Vcc) & pin 7 and make it an 820 ohm resistor, put R2 & R3 (variable resistor or "pot" {ugh}) between pin 7 & pin 6 (and also connected to pin 2 on the pin 6 side) in series... make R2 a 45k ohm resistor and make R3 a linear 300k ohm variable resistor. Connect a cap, C1, between the pin 6/pin 2 connection from R3 to GND and make it a 20nF (.02 uF). Connect pin 1 to GND (0V). Using the variable resistor, you can change the output frequency on pin 3 between 104 - 794 Hz with a duty cycle that is pretty close to the exact 50-50% duty cycle that the Tesla switch design requires. (Pin 5 can be ignored for this)

The output of the 555 circuit is connected to the base of the transistors (or in the second diagram, to the input to the optoisolators). The second diagram only shows one of the two states of the TS setup. The OTHER setup also has the input from the 555 circuit, but it is inverted (for this circuit, instead of using the standard 7404 inverter, I'd suggest using the 4069 inverter... it runs at the same voltages as the 555).

I think what they mean is that the TC4450 is switched by the 555 circuit and used to drive the optos...

The short answer on the resistor value is "it depends". The longer explanation is that the resistor is based on the current output of the optoisolator and is used to set the current being driven into the base of the NPNs & PNP transistors. The value depends on the desired base current of the choice of NPN & PNP transistors as well as the output from the optoisolator chosen.

Good Luck,

ITF

[mlindeblom]

FET driver

Hello,
They say: "The output from Pin 3 needs to drive a very sharp switching combination such as a TC4420 FET driver connected
to IRF540 FETs." I don't get it. Are these transistoris the ones used in the previous image? How? Please help.

FETs generate lots of heat called conduction losses if not switched quickly. FET drivers such as a TC4420 need closely positioned ceramic bypass capacitors 0.1 uF to 1 uF to supply the large switching currents used. See http://www.fairchildsemi.com/ds/FA/FAN3100T.pdf for information on another FET driver.

In my Bedini SS running at 2 to 15 KHZ, I just about burn myself on the FET heatsink without the driver. It runs very cool to slightly warm with the driver.

I suspect at less than 100 Hz the driver would not be needed.

[mlindeblom]

Opto FET/IGBT driver combo to use?

Field Effect Transistors and Insulated Gate Bipolar Transistors are lower cost than Bipolar Junction Transistors such as MJL21194. For example an FGPF45N45T is rated at 450v at 45 Amp (http://www.fairchildsemi.com/ds/FG/FGPF45N45T.pdf) for $2USD, $16USD for 10 at Digikey.

The opto driver http://www.fairchildsemi.com/ds/FO/FOD3120.pdf would most likely work. Fairchild says it will drive 20 Amp FETs' and IGBTs. Use bypass capacitors to ensure good switching.

These parts are new and I have not used them; however: the specs look good for this application.

[nvisser]

Confused

[QUOTE=mlindeblom;37710]FETs generate lots of heat called conduction losses if not switched quickly. FET drivers such as a TC4420 need closely positioned ceramic bypass capacitors 0.1 uF to 1 uF to supply the large switching currents used.

My textbook says that mosfets draw no current on the gate and that they are switched with voltage
Why is it that the mosfet drivers can supply up to 9A to the base?

[lighty]

Your textbook is not fully correct. MOSFET gate have some intrinsic capacitance. That means that when you apply voltage between gate and source some current will flow from voltage source in order to charge that capacitance and when you turn gate signal off the opposite happens. In order to use MOSFET as switch you have to turn it on and off as fast as possible in order to have as short linear region transition time as possible. Also, depending on the load on MOSFET (to be more precise depending on the load current) the things could get even more complicated for plethora or reasons and the requirements become even harder on the gate voltage source. So you have to have voltage source which is capable of putting out current necessary for charging gate capacitance as fast as possible (when you turn on MOSFET) and to sink charge from gate capacitance as fast as possible (when you turn off MOSFET).

This is very simplified explanation as this is not appropriate forum for basics of electronics and I also don't have much time to type long explanations. I suggest you go to EDAboard.com - Electronics Forum, Projects, Schematics, Circuits, Books, Microcontrollers, ASIC, DSP, RTOS, RF, Digital Design, Analog Design, Programming, Circuits, Service Manuals and learn more about MOSFETs.

I also suggest that you read http://http://www.irf.com/technical-info/appnotes/mosfet.pdf and especially part about gate charge.

I hope I helped a bit.

[morpher44]

switching too fast

and switching fast might not be what you want with LEAD acid batteries.

You need time for the ion flow in the chemistry of the battery to
charge.

Also, charging LEAD acid batteries is not always as simple as just
applying a current.

Perhaps opto-isolation and power transistors are a better way to go.

[lighty]

@morpher44

Switching fast doesn't apply to length of the impulse or to the repetition rate but rather to the time it takes for any kind of transistor to open- doesn't matter if it's MOSFET or BJT. Also if any transistor opens too slow it will cause additional power dissipation in the linear region. In other words transistor will not behave as switch but rather like switch/load.

As for the opto-isolation- again it's much easer using MOSFETs or IGBTs because they are somewhat more intuitive to use for layman because they are voltage driven devices.

I tnink you should also check those links I gave to nvisser.

[nvisser]

[QUOTE=morpher44;67607]and switching fast might not be what you want with LEAD acid batteries.

Switching fast might mean the rise time and not the duration or duty cycle
Thank you Lighty for your answer. That finally clears that up for me

[morpher44]

3

@morpher44
Switching fast doesn't apply to length of the impulse or to the repetition rate but rather to the time it takes for any kind of transistor to open- doesn't matter if it's MOSFET or BJT.

Yes. I see. Your right.
I was imagining high frequency pules.. oops.
Yes tuning the pulses, I think, is key with the Tesla switch ...
and knowing the speed of the ionic flow within the LEAD ACID battery,
or rather the resonance of the battery, will lead to success.

Bearden/Bedini and others implied that LEAD ACID batteries can be
"fooled" into charging with a little quick pules to get the ionic flow
in the "charge" direction using only a brief potential applied.
This all sounds so magically, however, I can hear BUBBLING in the
batteries when attempting to do it too fast!!!

BTW, Tesla was really into the number three.
You would think that a Tesla circuit for a Tesla switch would
not create a back and forth between two pairs of batteries;
alternating series and parallel connections.
Rather, you would think that Tesla would use three phases.
Imagine 3 pairs of batteries: pair A, pair B and pair C.
Imagine a rotary switch that provided the phased connections you
want.
Imagine pair A connected in series charging pair B in parallel,
then pair B in series charging pair C in parallel,
then pair C in series charging pair A in parallel.

Of the 3 phase, each pair gets one phase where it is unconnected.
During this quiet time, it can "charge" if the flow was
already started in that "charge" direction.

Yes you need 6 batteries .... but just throwing this idea
out there in case anyone wants to consider it.

btw, the load is always switched between the current flow.

[3dsorcery]

Can someone review my 4 battery circuit schematic?

Hey Guys,

I was wondering if you could take a look at this version of the 4 battery tesla switched that I've designed. I have this circuit breadboarded, but it's not working properly.

I'm wondering if I have some glaring issues with the way the circuit runs. I'm pretty new to electronics, so please look for basic mistakes.

Thanks!

Chris

[Groundloop]

Hi,

My Tesla switch replication can be downloaded from here:
http://home.no/ufoufoufoufo/BediniTeslaSwitch.rar








GL.

[Matthew Jones]

Hey Guys,
I was wondering if you could take a look at this version of the 4 battery tesla switched that I've designed. I have this circuit breadboarded, but it's not working properly.
I'm wondering if I have some glaring issues with the way the circuit runs. I'm pretty new to electronics, so please look for basic mistakes.
Thanks!
Chris

Several things look wrong on the schematic. I don't know how they ended when you built it but...

You have no means for serial connection. SO your not raising the voltage to 24 volt.
You also have the transistors driving straight from an IC controller. They will not fire that way. You need to use an Opto Isolator and drive them with power from the battery they are hooked to.

If your just getting started building Tesla Switch's you may consider coming and seeing us at:
http://www.energeticforum.com/renewa...la-switch.html

This is an active thread and we have several versions available as well as alot of history to read through.

This is the most current version that I have running right now and it is SIMPLE as they get. JUst have to wind up a coil or transformer.
http://www.matthewcjones.com/power/SimpleSwitch.jpg

Cheers
Matt

[3dsorcery]

Thanks for the reply Matt!

A few things...

Several things look wrong on the schematic. I don't know how they ended when you built it but...

It was an interesting result actually for how wrong the schematic most likely is. I was getting some strange voltages that were pulsing in time with my circuit (I programmed the Arduino to pulse every second with the hopes of basically switching the batteries once per second as an initial test). No transistors fried and nothing got hot, so it wasn't all bad I guess I was hoping to see 12v and 24v, but instead I was getting odd values like 6v and 15v and such.

You have no means for serial connection. SO your not raising the voltage to 24 volt.

If you look at the two transistors on the left side of the circuit, take the one on the top to be SwitchA and the one on the bottom to be SwitchB. If you turned SwitchA ON and turn SwitchB OFF, you get a serial connection between the two batteries on that side of the circuit. At least that's how I inteded it to function, so I would definitely appreciate knowing where I went wrong there.

You also have the transistors driving straight from an IC controller. They will not fire that way. You need to use an Opto Isolator and drive them with power from the battery they are hooked to.

I did not know that! I'm curious though as to why the transistors wouldn't fire directly from the IC? It provides a 5v output and I thought that would be enough. It worked on a simple circuit I made using the same principle and I just turned a motor on and off everyone 1/2 second.

This is the most current version that I have running right now and it is SIMPLE as they get. JUst have to wind up a coil or transformer.
http://www.matthewcjones.com/power/SimpleSwitch.jpg

This looks pretty cool! I will definitely try to put one of these together as it looks pretty simple to build.