Use for the Tesla Switch

[shadowless]

I was using a 100ma 12v bulb, made a mistake in earlier post.

Was using 18awg wire wound to the max that the transformer can take. Will have to test out with thinner 20awg wire.

If you use different load on the TS, the output voltage will vary. Smaller load will give higher voltage and larger load will have lower voltage. For the direction connection to the battery it will just supply whatever the bulb requires. Putting a 5-10w 12v dimly lit bulb on the TS would not be a good test comparison test.

I do think the load should be supplied with the same voltage and current in both situation to make the comparison test meaningful hence i am asking about the clarification on it.

[jpolakow]

I want to ask about doing the baseline 4 battery parallel discharge test.

Say if with the TS switch, you can generate a output of 10.5v max when loading it down with a 12v 100amp bulb, when you discharge the 4 batteries in parallel do you add a pot to adjust down the voltage of the bulb to the same 10.5v draw (so that it glows at a similar brightness as the TS test)in order to make a comparable test.

Hi shadowless. If you wound the transformer correctly you should get more than 12 volts output. The secondary winding on the transformer is supposed to be 20% longer. Which should boost the voltage. After going through the bridge rectifier, the dc voltage for me is anywhere between 13-20 volts. For me the output is ALWAYS higher than the voltage of the batteries individually. So you shouldn't have to dial it down for the batts in parallel.

[Sobakin]

I want to ask about doing the baseline 4 battery parallel discharge test.

Say if with the TS switch, you can generate a output of 10.5v max when loading it down with a 12v 100amp bulb, when you discharge the 4 batteries in parallel do you add a pot to adjust down the voltage of the bulb to the same 10.5v draw (so that it glows at a similar brightness as the TS test)in order to make a comparable test.

What's why I did another baseline test with same transformer, for this I built H-bridge inverter, which powered by 4 batteries in parallel, so they are only discharged simultaneously to transformer and load.
I didn't found any advantage in TS against inverter with both types of batteries (I have 4x 12V 1.3 A-h SLA and 4x 12V 4 A-h flood acid batteries), and different loads (6W bulb and 21W bulb), time was the same as with inverter.
Tried different TS: Matt's 2-switch with mosfets, another with bipolar MJLs and symmetric 6-switch with mosfets, different loads, different batteries, different frequencies, different transformers (two iron, two ferrite) have done about 30 tests - result the same, +/- 5%.
W/o transformer I got discharge time even better, no transformer loss due primary's current consumption gain because of voltage gain in secondary.
6W bulb consumes 0.45A itself but transformer's input current about 0.55A.
Don't know how Matt managed to get up to 8x discharge time, for me it's a big secret

[shadowless]

I want to ask about doing the baseline 4 battery parallel discharge test.

Say if with the TS switch, you can generate a output of 10.5v max when loading it down with a 12v 100ma bulb, when you discharge the 4 batteries in parallel do you add a pot to adjust down the voltage of the bulb to the same 10.5v draw (so that it glows at a similar brightness as the TS test)in order to make a comparable test.

[jpolakow]

Thankyou dnewkirk!

[dnewkirk]

Look at the attached drawing on nvisser's post, #3797.
You'll see diodes D3 & D4 added to capture the inductive kickback energy and apply it to the charging batteries (+) buss.

[Sobakin]

So I've got a question... can we harness the inductive kickback of the coil? I mean we pulse the coil, then we get a high voltage kickback. Why not harness this kickback in a cap and use it to either charge the batts -or pulse it back into the coil to get an even higher kickback/power out of the secondary. Is this feasible?

I think charging caps by this spikes is not effective, energy is very small, maybe it's better to direct them back to batteries.

[jpolakow]

Back EMF

So I've got a question... can we harness the inductive kickback of the coil? I mean we pulse the coil, then we get a high voltage kickback. Why not harness this kickback in a cap and use it to either charge the batts -or pulse it back into the coil to get an even higher kickback/power out of the secondary. Is this feasible?

[gtmbiz]

i need help

Hi Peter,
A big hello to all members i am new here and would be glad if any one that have an ultimate knowledge on the innovative idea on how to build tesla coil to power a bulb light.Please if you can help i need help for Tesla coil electric bulb my contact is [email protected] Hoping to hear from you soonest

[Sobakin]

Hi Carroll,
I started my switch up today to do some tuning and I got some very strange behavior. When I first started the switch up my halogen bulb lit up super bright and then died. I figured there was a bad connection somewhere so I took out my DMM and took a reading at the caps(no load). I got 44 volts DC! I figured something was amiss so I turned off the switch, checked my connections and restarted the switch- now I got 24 volts and it slowly climbs higher by .01 volts at a time until about 26.75 volts. If I hook up a bulb, it will drop to around 14 volts pretty rapidly. Then If I disconnect the load again the output will jump to 22 volts pretty quickly, and then climb to 26, 27, or 28 volts (by .01 increments) depending on how long I wait.

It's a back-EMF spikes between pulses when transformer has no load, they are relatively high-voltage and very short in time, caps after rectifer can absorb them, and you can see a voltage gain in caps. Lower capacipy caps rises voltage faster.
Try not to exceed cap's maximum voltage, because it could explode.

[jpolakow]

Readings

Here is a picture of what I'm claiming. In the lower left corner you can see the yellow wires with alligator clips. They are connecting the bulb in series with the green winding primary.In the lower right corner you see the meter reading 69.4 volts. This is connected to the green wires with alligator clips, which in turn are connected to the output at the caps. In the upper right corner you see the other meter with a reading of 13.6 vac. this meter is connected to the output of the trafo(red wires) with the white wires with alligator clips

[jpolakow]

Strange readings

Edit: I have been able to replicate my previous strange readings. What I did was connect a bulb in series with one of the transformer windings, to see how running a load in series with the transformer would influence output. Right now with a bulb in series with one of the primaries I am getting 70 VDC steady state out at the caps, but with only 13.6 VAC at the transformer. How the heck is it jumping from 13.6 to 70 just going through the rectifier??? I've checked the readings with two separate meters to verify.

Also if I short the dc output quicly it jumps right back up to 70!! Do you think some kind of resonance thing is going on?

In regards to my second question I was suggesting two cap banks. One to run the load from while the other cap bank charges. Then flip flopping them.

Thanks!

[citfta]

Hi John,

Well to answer your first question, what you are seeing is one of the interesting things about this transformer setup. The caps would normally charge to the PEP value of the current if the current was a true sine wave and there was no load on the cap. You are driving the transformer with short pulses of DC that are close to a square wave and not a true AC sine wave. So you are seeing some strange things as shown by your meter. Another thing to remember is if you are using a digital mutimeter they are designed for a sine wave too and don't handle other signals too well. The DC voltage on the cap is probably pretty close to right but your RMS value shown on the meter may not be.

To answer your second question, what is going to keep your load running while you are recharging the cap? Also if you run some tests you will see when the cap is fully charged you have almost no current flowing on the primary side so you won't get any charging of your top batteries. It is something else for you to play with and see if you can find a way to dump the cap into your load and still keep everything else working the way you want it to. Have fun.

Carroll

[jpolakow]

Strange readings

Hi Carroll,
I started my switch up today to do some tuning and I got some very strange behavior. When I first started the switch up my halogen bulb lit up super bright and then died. I figured there was a bad connection somewhere so I took out my DMM and took a reading at the caps(no load). I got 44 volts DC! I figured something was amiss so I turned off the switch, checked my connections and restarted the switch- now I got 24 volts and it slowly climbs higher by .01 volts at a time until about 26.75 volts. If I hook up a bulb, it will drop to around 14 volts pretty rapidly. Then If I disconnect the load again the output will jump to 22 volts pretty quickly, and then climb to 26, 27, or 28 volts (by .01 increments) depending on how long I wait. I'm still getting 17 volts out AC (rms) at the transformer. Isn't the rms value supposed to be what the equivalent dc voltage is if it's rectified? Very strange.... especially that the dc out slowly rises.

Also I have a second question- I have more tuning to do, and did realize my bottom batteries dropped much more rapidly with the 20w load. If we find the ideal load size for a given switch, can we simulate that load size with a capacitor bank? Then have the cap bank disconnect from the rectifier and run the load while the rectifier charges cap bank #2. Have some switching so the load is always independent of the rectifier output, enabling you to run any load size independent of the best value for the switch? Just an idea.

Thanks!

[dnewkirk]