Mosfet Heating Circuits

[Guruji]

Negative waveform generator

Hi Fuzzy did you try to build the negative waveform generator circuit by Aaron?
It's with one 12v battery. The thing is that he says that there was no heat in his resistor while when I replicated it ;mine is got heated.
It's consuming around 12w true but it's efficient to conventional elements.
If someone replicate this circuit I am looking forward to discuss with him.
Thanks
Andrew

[FuzzyTomCat]

Negative Dominate Wave Form - Replication

Hi Fuzzy did you try to build the negative waveform generator circuit by Aaron?
It's with one 12v battery. The thing is that he says that there was no heat in his resistor while when I replicated it ;mine is got heated.
It's consuming around 12w true but it's efficient to conventional elements.
If someone replicate this circuit I am looking forward to discuss with him.
Thanks
Andrew

Hi Andrew,

Yep ... I have tried and documented here at Energetic Forum Aaron's "Negative Dominate Wave" form generator circuit and here are the links ...

Post #2606 (Tektronix 2445A Scope)

Post #2764 (Tektronix TDS 3054C Scope - Part 1)

Post #2766 (Tektronix TDS 3054C Scope - Part 2)

Aaron's "Negative Dominate Wave" form generator schematic is totally different from the "Mosfet Heating" circuit and the #2606 posting was my attempt using my Scope.

The other two postings #2764 and #2766 was on a Tektronix TDS 3054C that was available for my use at Aaron's residence for a time and he was able to fine tune my replication, being he was much more familiar with the circuit and the Scope being used ..... he has much more time and effort in this circuit than anyone I know.

Hope this helps ...

Best Regards,
Glen

[Guruji]

Heater

Fuzzy thanks for your help. My pots are adjusted like this :
1K pot=24ohms
5kpot=412ohms
2kpot=955ohms
10kpot2.88Kohms
Another thing I used 1n4148 diodes instead of 1n914.
Thanks
Andrew

[FuzzyTomCat]

Fuzzy thanks for your help. My pots are adjusted like this :
1K pot=24ohms
5kpot=412ohms
2kpot=955ohms
10kpot2.88Kohms
Another thing I used 1n4148 diodes instead of 1n914.
Thanks
Andrew

Hi Guruji,

The DMM Ohm reading is this taking in consideration for the resistance of the test leads ? My DMM's vary from .2 to .4 ohms that needs to be deducted from the resistance measured, if you know this cool, but maybe some other members or guests may not be aware of this fact.

Best Regards,
Glen

[FuzzyTomCat]

Tektronix "Open Choice Desktop" Software

Hi everyone,

The Images and test data from Test #17 through Test #22 was acquired using a Tektronix DPO 3054 Oscilloscope and downloaded with software supplied free by Tektronix called "Open Choice Desktop" with Visa directly to you computer via a USB cable from a 2.0 compliant port.

Using this software for data analysis is "great" the type .csv file used the data actually includes a exact color copy of the wave form image the data came from just by opening the .csv file up using the "Open Choice Desktop" with Visa software. It's quite a large software file about 117 MB but the image data is incredible and a extremely useful addition.


OPENCHOICE DESKTOP APPLICATION TDSPCS1 v1.8
OPENCHOICE DESKTOP APPLICATION TDSPCS1 v1.8 > Software Downloads : Tektronix

COMPUTER REQUIREMENTS
PC equipped with Windows 2000, XP PRO or Vista 800+ MHz, 500MB RAM, HD, Mouse, Keyboard. Connected by GPIB, USB, RS232 or LAN to a compatible Tektronix oscilloscope. VISA (Virtual Instrument Software Architecture) must be installed on the PC for OpenChoice Desktop to work collecting actual data from a compatible Tektronix oscilloscope. Please read the Instructions on this web page to get an appropriate version of VISA for data collection.

Best Regards,
Glen

[ashtweth]

Course updated (Feb 19, 2010):
http://www.panaceauniversity.org/Ros...Technology.pdf

H, Glen, let me know if any tweaks needed.

Ash

[Guruji]

water heater

Hi guys did anyone try this circuit to a water heater? I tried mine with a little nichrome wire rapped to the brass tube under the water heater but no results cause there has to be a flow or the heater should be immersed in water. Anyone tried this?
Thanks
Thanks

[ashtweth]

Hi Guruji thanks for the report how did you tune your circuit?, Did you use a scope and get the harmonic and wave form? we could with a 100mhzh scope but not keep it there, still need better equipment to fine tune.

Fuzz, H and many others including for a change Rose LOL have made some helpful hints on this in the communities PDF

[Guruji]

Hi Guruji thanks for the report how did you tune your circuit?, Did you use a scope and get the harmonic and wave form? we could with a 100mhzh scope but not keep it there, still need better equipment to fine tune.

Fuzz, H and many others including for a change Rose LOL have made some helpful hints on this in the communities PDF

Hi Ashweth I don't have a scope it was with patience about tuning. I adjust the pots with my hand on the resistor. When I feel a little heat coming then I take note of the resistors. Then I try to adjust a little more for more heat.
Now I am trying to find resonce on a water heater filament maybe I will find resonance on this too. I can say that it happened at one moment but I was'nt that aware and lost the settings.
I'm still trying on this.
Thanks
Andrew

[Harvey]

Temperature Profile

Hi All,

I have finally completed all of the Master Files for Tests 17 - 22 and uploaded them to the repository for team access. It is my wish that these files be made available to everyone so that careful analysis can be done on them. The two large databases for Test 21 and 22 are over 250MB due to the data sample resolution of 10 times that of previous tests. But I have zipped them into RAR format of about 35MB for those with Microsoft Access that would like to have a copy of the program I wrote for those analyses. I am open to suggestions for a convenient means to make those available to everyone.

Here is a quick link to the original Temperature Profile which you will want to use when evaluating that data:

Glens Post With Original Temperature Profile

Please note the difference between Ambient and the Resistor Temp in these readings as this is important when evaluating the proper power reading associated with a given temperature in the various tests.

There is a lot of data here and I am still working out what it all means, but there are a couple of things that stand out in these tests that we missed in the earlier tests.

First of all, we did not do power graphs in the previous tests. If we had, we may have seen the gradual ( > 400 us ) drift of the power center-line above and below the voltage source reference.

Secondly, the 100,000 sample data reveals transients that are simply left out of the smaller resolution data. Some of these transients are significant as they directly impact the power averages.

Another thing that really pops out in these tests is the AC current. This can be very problematic when trying to use Rosemary's method of analysis which presumes that all negative current is to be subtracted from the DC supply consumption. I hope to address this concern in greater depth in later posts here, but the simple issue is that AC current on the CSR will net to zero using her method even when real power is dissipated in the load. We need a definitive way to separate the AC power from the DC power in the analysis.

Hopefully I can do a short video on some of these points within the next week.

Cheers,

[Harvey]

Determining The Inductance of Our Resistors

Hi All,

In this post I would like to address as concisely as possible the subject that has been asked, alluded to, mildly discussed and never actually answered.

How can we accurately determine the inductance of our DIY resistors?

It may seem on the surface that a premium LCR meter would suffice, but we would always question whether this would accurately separate the resistance from the inductance since these are both integrated into the same device. Also, what of us who do not have an LCR meter?

With a couple of formulas, an AC Ammeter and an AC signal generator the matter can be handled.

I will not be going into all of the deep technical aspects of the imaginary parts of complex numbers and how they play into this but I will be converting from the polar coordinate values given by our Ammeter and the rectangular coordinate system used to extract the inductance. You can refer here for more information: Series resistor-inductor circuits : REACTANCE AND IMPEDANCE -- INDUCTIVE

There are two formulas to consider:

1. XL = 2πfL which is also expressed as L = XL / 2πf
2. |Z| = √(XL² + R²)

You may recognize the second formula as the Pythagorean Theorem. This is because the absolute impedance is the vector described by a 0° phase shift in the Resistor and the 90° phase shift in the inductor. Visually, you would see one vector running horizontal, the other vertical and the result is the hypotenuse of the two.

Let's use Glen's resistor as the device under consideration. His resistor has a DC resistance of 10 Ohms, this is our R value.

For the test we will need a Function Generator able to produce a 10V AC sine wave with at least 1A capable of being tuned to 79.5 kHz. I have chosen those values only because they make this example easier to follow.

Step 1:
We place the AC Ammeter in series with the resistor and run the 79.5 kHz sine wave signal through it. I would expect to see a current of about 0.707A (seven hundred seven milliamps). With this information we can now determine the inductance of the resistor.

Step 2:
|Z| = 10 volts over 707 milliamps or 14.144 Ohms. Now this is a complex number, a vector - we cannot simply subtract 10 ohms to find our XL portion of the absolute impedance |Z|. We must apply Formula 2. Therefore we get XL² = 14.144² - R² or simply, the inductive reactance squared equals the total impedance squared minus the resistor value squared orXL² = 14.144² - 10². This becomes 100 = 200 - 100 (simple eh?) So, XL = √100 which is 10.

Step 3:
Now that we know the inductive reactance, we can use Formula 1 to get the inductance of the resistor. This is simply Ten divided by (two times Pi times 79500) which is XL / 2πf where f is frequency in Hertz. The result will be in Henries. To convert it to µH simply divide it by 10^-6.

So what do you calculate the result to be? Well, this exercise is purely hypothetical, Glen would have to perform the test and tell us what he really gets. But if his current was 707mA as shown here, then the resistor would have an inductance of about 20µH.

[ashtweth]

Harvey it hurts my head to think how smart you are.
Thanks a lot for posting man.

[Harvey]

Thanx for the complement Ash , but really all I did there was apply some general knowledge already on the net to our specific needs. The real credit goes to those great minds like Oliver Heaviside that brought it all into perspective for us.

[Guruji]

44ohm filament

Hi guys anyone with a scope and try a water heater filament with a Negative form generator circuit of Murakami with one 12v battery please?
I really want to see if this filament would heat up.
Thanks

[FuzzyTomCat]

Hi guys anyone with a scope and try a water heater filament with a Negative form generator circuit of Murakami with one 12v battery please?
I really want to see if this filament would heat up.
Thanks

Hi,

Just wanted to add some information on the International Rectifier - IRFPG50 HEXFET® Power MOSFET (w/ Sil-Pad insulator between Mosfet and Heat Sink), is that although it's rated at 1000 Volts it does have a 6.1 Amp limitation ...

Best Regards,
Glen