Language:
To browser these website, it's necessary to store cookies on your computer.
The cookies contain no personal information, they are required for program control.
the storage of cookies while browsing this website, on Login and Register.
 Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here: https://overunity.com/5553/privacy-policy/If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

Custom Search

### Author Topic: Simple to build isolation transformer that consumes less power than it gives out  (Read 349428 times)

#### Jack Noskills

• Sr. Member
• Posts: 346
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #330 on: October 22, 2012, 01:56:36 PM »
Voltage drop in the current limiter bulb shows that it is not consuming power but the second is. If considered as a black box then there is amps going in but volts stay the almost the same. So how should power consumed be computed in the first place ? If there is 25 mA going in and voltage drop is 3 volts, then is power used equal to 25 mA * 3 volts = 0.075 watts while you got 7.5 watts bulb lit maybe at 120 volts and 25 mA ?

I am saying you consumed 0.075 watts, prove me wrong. This is the question that would need an answer.

There is also the case of harmonics. 50 Hz input signal creates harmonics up 1 kHz according to test report shown earlier in this thread. Is it possible by using a filter to take only the power from the harmonics ? Make a tank circuit on output side that blocks 50 Hz signal, don't know, just throwing an idea which I cannot test. There is another way to create different frequencies out of one drive frequency, I discovered it when I tested three core trafo. I was unable to make anything out of that though, but maybe someone else could. I think this same effect happens in Tesla's rotating pole trafo. To create effect atleast two poles were needed and they are connected together capacitively using coil. Iron coil as a core where poles are (oxidised iron so there is insulation), or using three cores connected as shown in the second thread I made here.

You could measure the efficiency of your system and compare. Use two trafo setup and measure efficiency of second trafo when it is connected in normal mode and when it is rewired.

#### forest

• Hero Member
• Posts: 4070
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #331 on: October 22, 2012, 05:28:29 PM »
Well, I proved to myself that it's not a simple OU transformer  I have now a few 1:1 trafos to test and that one 20W I have has really minimal idle current of 4,75mA. No luck however. All I measured was drop to 3,7mA when connecting 0.9W bulb but this is easily explained by current avoiding secondary of transformer and going directly to the LED bulb.

I don't understand you computation, I have to think about it more, hmmmmm....... Can you explain it ? Ohm law was always hard task for me . I think what we expected was current drop in primary of first transformer as indicated by your statements about blink of limiter bulb and then fade back to cold state. I didn't saw that - everytime current was higher then when unloaded and I measured it using digital ampermeter also .  Except one case when the idle current was higher then the current required to power load like in case of 0,9W LED bulb. Then I saw a little weaker glowing filament and then lowered current...

Jack, what I assume is : you didn't told us everything about your original setup, at least something very important which may look like unimportant. Maybe it is inside trafos you have (wire kind, area of winding , core permeability or saturation) , or maybe it is the orientation in space of those trafos ? Maybe they are just placed in such manner as constructing effectively kind of flux path device , like Thane transformer or many others with deflection of BEMF flux ?

Anyway it was busy few days (even more ) to construct those trafos, but I feel it was not wasted time ,because I have now one or two ideas how to use them. I was interested in your setup due to simplicity and because it might prove my theory that every transformer could be made almost 200% efficient (without resonance ) because the magnetic flux ( in secondary and primary) is really free to go if we can eliminate Lenz law effectively.

#### Jack Noskills

• Sr. Member
• Posts: 346
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #332 on: October 25, 2012, 11:24:23 AM »
I shared everything there is to share, no hidden parts or secrets. What might explain this is the efficiency of the trafos, I had quite efficient iron trafo. If I put bulbs on each side when using it as normal trafo they were almost equal brightness. If efficiency is below 50% then you will not get OU, I think efficiency needs to be closer to 90 %. Some poster said that laminated iron (stepdown ?) E-I trafos are typically 30 % efficient.

You could measure efficiency of your trafo in normal mode and when rewired. Is rewired more efficient compared to normal mode trafo ? If so, then what would happen if efficiency of trafo in normal mode is close to 90 % ?

As for my view of power computation, power needs volts and amps. The current limiter bulb is showing that only amps go through it but voltage drop is close to zero. So limiter bulb is not consuming power and it does not glow. If you put more bulbs in the load side, then you should see current limiter bulb beginning to glow more and now it is using real power. When current is entering circuit but there is no voltage drop across load then power is not used right ? But the meter is now measuring current and not power so meter does not show power consumed. We should use DSO to get power measurement, not rely that voltage difference is fixed to a certain high value. This is my interpretation anyway.

I share your view of 'every trafo can be made 200 % efficient without resonance', and this setup is just about that. So don't dump this experiment just yet, investigate it some more, measure current going in various places and voltage drop, efficiency of your trafos etc. Forget the ohms law, it might not apply here in every part of the circuit.

#### forest

• Hero Member
• Posts: 4070
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #333 on: November 01, 2012, 06:02:33 PM »
Ok Jack I will return to this transformers and make proposed measurements. Btw I checked goldwave sound editor and it can generate only one sinewave , which is quite unusable to sweep over range to find sweet spot.

Here are better ones I plan to check : http://3d2f.com/tags/sine/wave/generator/software/

#### Jack Noskills

• Sr. Member
• Posts: 346
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #334 on: November 02, 2012, 08:02:56 AM »
goldwave can produce all kind of waves and frequencies, check the expression evaluator. Under +Waves list in evaluator there is sweep from x to y:

sin(2*pi*(((n/N/2)*(y-x))+x)*t)

Below dial tone #, contains of two frequencies. My sample rate was 44100 Hz so constants seem large. DTMF tones are in below 1 kHz.

(sin(5912*t)+sin(9280*t))/2

So you can program this thing to what ever you need, even stereo output for more exotic tests. You can use full sine or positive sine, just add constants in the expression. Square sweep is

step(-int((((n/N/2)*(y-x))+x)*t)%4)

%4 controls the on/off ratio. Similar to sine() but now step() function used instead of sine().

#### forest

• Hero Member
• Posts: 4070
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #335 on: November 02, 2012, 05:45:59 PM »
Thank You Jack I just wanted to help.  I think we need a tool which can do sweep at slow rate while displaying  frequency and able to pause when required still producing output. Such tool would allow to find resonant frequency easily. Sadly I must confess I haven't found such one yet.

#### TinselKoala

• Hero Member
• Posts: 13958
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #336 on: November 02, 2012, 07:02:55 PM »
As Jack has described, GoldWave will do what you need in the audio range, it just needs a little programming.

But why not invest in a decent function generator with sweep capability? The FG, along with the oscilloscope, is the basis of any setup for looking at resonant circuits or just electronics tinkering in general.
Any signal generator will allow you to sweep manually, and you can just stop turning the knob when you see the resonant voltage rise on the scope, and read off the numbers from the FG's or scope's display. Most common, low-end FGs these days will cover a range up to 3 or 5 MHz and many also even include sweep function.
I have an old Interstate F34 Sweep Function Generator that I use for coil tuning, letting it sweep automatically, but this is a luxury. It's easy enough to do manually with the right tools.

#### forest

• Hero Member
• Posts: 4070
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #337 on: November 03, 2012, 07:47:54 AM »
As Jack has described, GoldWave will do what you need in the audio range, it just needs a little programming.

But why not invest in a decent function generator with sweep capability? The FG, along with the oscilloscope, is the basis of any setup for looking at resonant circuits or just electronics tinkering in general.
Any signal generator will allow you to sweep manually, and you can just stop turning the knob when you see the resonant voltage rise on the scope, and read off the numbers from the FG's or scope's display. Most common, low-end FGs these days will cover a range up to 3 or 5 MHz and many also even include sweep function.
I have an old Interstate F34 Sweep Function Generator that I use for coil tuning, letting it sweep automatically, but this is a luxury. It's easy enough to do manually with the right tools.

Answer is simple. I'm short on money and function generators are costly. Do you know maybe about any cheap one , maybe extension slot for PC ?

#### DreamThinkBuild

• Hero Member
• Posts: 574
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #338 on: November 03, 2012, 01:31:59 PM »
Hi Forest,

If you need to generate more specific frequencies I suggest Octave(which is Open Source).

http://www.gnu.org/software/octave/

Using the chirp function is a snap to generate swept frequencies or any other kind of signal. You can keep changing the parameters until you narrow down the frequency range.

Quick example:

Quote
%Notes:
% - The duration should be set longer than this example for
%better low frequency accuracy
%
% - You can change the starting phase angle which is an
%optional parameter for chirp.

%Clean up workspace
clear;
clc;

%Inputs
StartFreq=1;    %Hz
EndFreq=100;    %Hz
Duration=2;    %Seconds
SampleRate=48000; %Samples per second
OutputFile='MySweep.wav'; %Output filename

%Set time frame
t=1/SampleRate;    %Time period
tp=0:t:Duration; %Time over duration

%Generate swept output signal with chirp (normalized)
OutSignal=chirp(tp,StartFreq,Duration,EndFreq);

%Save generated signal to wave file
wavwrite(OutSignal,SampleRate,32,OutputFile);

You can also play the signal out to the soundcard directly but it depends on if your computer will recognize the command(soundsc). soundsc(OutSignal,SampleRate);

#### TinselKoala

• Hero Member
• Posts: 13958
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #339 on: November 03, 2012, 08:08:42 PM »
Answer is simple. I'm short on money and function generators are costly. Do you know maybe about any cheap one , maybe extension slot for PC ?
I advise not using PC plugin cards. Unless of course you can afford the quality and performance of NI products and software like LabView.

What is your budget range? Don't forget that your signal generator will become one of the basic and most-often-used piece of gear in your laboratory.

Can you spend a hundred dollars?

http://www.ebay.com/itm/5MHz-DDS-Digital-Signal-Generator-Module-Sweep-Function-CPLD-STM32-NEW-/320774544820?_trksid=p3284.m263&_trkparms=algo%3DSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%26otn%3D21%26pmod%3D271094933774%26ps%3D54

http://www.ebay.com/itm/PROTEK-B-801-SWEEP-FUNCTION-GENERATOR-/360454232368?_trksid=p3284.m263&_trkparms=algo%3DSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%26otn%3D21%26pmod%3D271094933774%26ps%3D54

http://www.ebay.com/itm/Interstate-20MHz-Sweep-Function-Generator-F74-/271036923351?_trksid=p3284.m263&_trkparms=algo%3DSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%26otn%3D21%26pmod%3D271094933774%26ps%3D54

Better hurry, I just might buy that Interstate 20 MHz unit.

#### TinselKoala

• Hero Member
• Posts: 13958
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #340 on: November 03, 2012, 08:16:04 PM »
Hi Forest,

If you need to generate more specific frequencies I suggest Octave(which is Open Source).

http://www.gnu.org/software/octave/

Using the chirp function is a snap to generate swept frequencies or any other kind of signal. You can keep changing the parameters until you narrow down the frequency range.

Quick example:

You can also play the signal out to the soundcard directly but it depends on if your computer will recognize the command(soundsc). soundsc(OutSignal,SampleRate);

What's the maximum frequency you can get from a computer sound-card based function generator? I'd feel really cramped if I couldn't test above 50 kHz. The most basic FG that you can get these days will probably go to 2 or 3 MegaHz.... that is, 40 or sixty times higher frequency than you can get with a sound card.

#### TheCell

• Sr. Member
• Posts: 285
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #341 on: November 03, 2012, 10:02:15 PM »
Transformer / nonlinear Inductance OU simple Experiment : (and a few others)
http://ut27972.narod.ru/Book_2/109_B_2_p_109.htm

Translate with google , move to text below Fig. 2 (24)

(http://ut27972.narod.ru/Book_2/109_B_2_p_109.files/image025.jpg)
Конвертор = Converter = Inductance
<Quote>
When the load in the diagonal series with the lamp converter ( Figure 3 ), there is an unusual phenomenon: converter - passive element comprising besides the resistance, but the ammeter included in the diagonal shows that, despite the loss, the current in it sharply increases, respectively, in the diagonal lamp glows much brighter. [size=78%]<Quote>[/size]

#### DreamThinkBuild

• Hero Member
• Posts: 574
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #342 on: November 04, 2012, 01:58:05 PM »
Hi TinselKoala,

The max frequency range for some sound cards is around 20khz. A dedicated frequency generator would be better but it depends on how much Forest wants to spend.

#### TinselKoala

• Hero Member
• Posts: 13958
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #343 on: November 04, 2012, 06:23:45 PM »
Hi TinselKoala,

The max frequency range for some sound cards is around 20khz. A dedicated frequency generator would be better but it depends on how much Forest wants to spend.

Most modern soundcards can sample and play at 44 kHz, but 20 kHz is generally considered to be the top end of (young) human hearing. Most adults can't hear much above 14 kHz and many can't hear above 12 kHz. Try it yourself, see where your upper limit is.
http://www.phys.unsw.edu.au/jw/hearing.html

A signal generator based on the 555 timer chip, or the TS3001 or TS3002,  and built with 20 dollars in parts would be far superior, in my opinion, to a sound-card-based system for any frequencies higher than strict audio.

http://touchstonesemi.com/products/timers?gclid=CMLdx4XotbMCFUYw4AodR3oAyQ

My largest Tesla coil (air core certainly) has a resonant frequency of something like 80 kHz, and my smaller SSTCs generally resonate in the 300-800 kHz range. You really need to be able to go higher than audio frequencies if you are doing a lot of research involving resonance, standing waves, and VRSWR.

#### poynt99

• TPU-Elite
• Hero Member
• Posts: 3582
##### Re: Simple to build isolation transformer that consumes less power than it gives out
« Reply #344 on: November 04, 2012, 08:39:41 PM »
forest,

As an option, build one or two of these.