Reactive power - Reactive Generator research from GotoLuc - discussion thread

[poynt99]

Luc,

I forgot to ask you; you have +194mW displayed for GRID power when CH2 is inverted. What power is displayed when CH2 is NOT inverted?

[gotoluc]

Ah man!... things are getting much worse now ... I've got 90 watts out and a negative Mean.

Are you sure this is the right way?

I'm running out of water to cool my resistors

See the scope shot

Luc

[TinselKoala]

Why are Luc's scopeshots so pixellated? I've never seen them like that from a Tek scope before. Even if the traces themselves are rough because they only represent a small number of samples, the text boxes and the rest of the image should be in higher resolution, shouldn't they?

[gotoluc]

even isolation transformers can carry the earth ground across.

Really!... mine is just a raw transformer with 2 screws on each side, so only hot an neutral is connected on in and on scope side I don't connect the ground to anything. So how can ground be carried over?

Luc

[gotoluc]

Why are Luc's scopeshots so pixellated? I've never seen them like that from a Tek scope before. Even if the traces themselves are rough because they only represent a small number of samples, the text boxes and the rest of the image should be in higher resolution, shouldn't they?

Probably because I open them in windows image viewer and use screenshot pilot and make a png file so I can upload then. This site is not accepting bitmap (Tek regular file format) for some reason.

Luc

[gotoluc]

Here is a zip of the original file.

BTW, the load is 15 Ohm 1% 50w resistors connected to 3 Series 12v batteries at 37 volts DC, so no error on power to the load.

It's 1:25am and been a long day, so I'm closing up for the night. I'll pickup more of my 12v batteries from storage tomorrow so we can see how far we can take this.

Stay tuned and please try to find the error as this is too simple!

Luc

[tinman]

Probably because I open them in windows image viewer and use screenshot pilot and make a png file so I can upload then. This site is not accepting bitmap (Tek regular file format) for some reason.

Luc

Hi Luc
Dose your scope have a USB output?-this is how i take my screen shot's.I then open the saved file on the thumb drive in windows paint,and save as a JPEG.They come out just as i see it on the scope.

[poynt99]

Really!... mine is just a raw transformer with 2 screws on each side, so only hot an neutral is connected on in and on scope side I don't connect the ground to anything. So how can ground be carried over?

Luc

Mine does, and I think most variacs do too. Just saying that they can, but yours apparently doesn't.

[poynt99]

Here is a zip of the original file.

BTW, the load is 15 Ohm 1% 50w resistors connected to 3 Series 12v batteries at 37 volts DC, so no error on power to the load.

It's 1:25am and been a long day, so I'm closing up for the night. I'll pickup more of my 12v batteries from storage tomorrow so we can see how far we can take this.

Stay tuned and please try to find the error as this is too simple!

Luc

I'm not sure I'm following you there Luc. What are you doing exactly?

[tinman]

Quote Poynt: btw, I tried your little trick of using a x1 voltage probe as a "current probe" while setting up the channel to measure current directly with the proper scaling. Seems to work ok.  Sorry for giving you a hard time about that.

This is what it's all about guy's-even the best have things they can still learn.

Luc
In regards to your last video-something seems not right. Are your DMM's reading rms voltage?. The reason i ask is this.
The prime mover uses 157-158 watt's-with or with out the reactive circuit switched on.
Without the reactive circuit switched on,your exciter circuit meters read this- 167.2volts @ 1.405 amp's. This is 234.916 watt's -asumeing a power factor of 1.

Poynt-How can we get the power factor of the tank circuit?. If i place my scope across the cap for volts,and use a CSR for amp's,and the two wave forms are in phase,dose this mean a power factor of 1?.

[tinman]

In the scope shot's below,i have placed the probes so as the current channel(blue) is across a .1 ohm 5 watt resistor that is in series with the cap and exciter winding's.The voltage probe(yellow) is across the cap on the exciter circuit.Looking at the scope,i think we can eliminate any chance that our DMM's are giving us an accurate reading.You will also see that the voltage is leading the current by around 90*-if you can make any sence of the wave forms.
the scope shots below are without the reactive circuit in place.
1-both voltage and current.
2-voltage alone
3-current alone.

[tinman]

Below are the scope shots that acompany the above,but with the reactive circuit in place and running.

[tinman]

Okay, I understand. I posted above how to get there but you'll need a 100x probe to display the 240v


Okay, so you're sure by using the Inverted probe that the power I'm using from the grid is 194mW. If so, we have a big problem now!  because the load has 8 watts more than the input.

What to do now?

Luc

Luc-one thing is for sure-this is well worth looking at. I mean,who would ever have placed a scope across the exciter circuit of a generator to see what was going on in there?. Well now i have,and what a sight to see lol.

I would like to know more about the above mentioned circuit-could you post a scematic please?.
194mW in and 8.194Watts out-sounds like something i would realy like to try and replicate.

No matter what the outcome of this is,it has been a most enjoyable exercise-thanks so much Luc and Poynt for your efforts.

Brad

[TinselKoala]

I asked about the pixellated resolution of Luc's scopeshots from the Tek, which should be capable of a lot higher resolution.

Probably because I open them in windows image viewer and use screenshot pilot and make a png file so I can upload then. This site is not accepting bitmap (Tek regular file format) for some reason.

Luc

Hmm... this site doesn't accept .bmp uploads because they are large files and there are better image formats that save space.  You can take the Tek's native .bmp output and convert it to jpg or png in just about any graphics application, without loss of resolution.

And as I found out during the Ainslie affair, if you don't actually convert but simply change the extension from .bmp to .jpg, the file will then upload to the forum and display in-line here on the forum, but when it is downloaded to our computers from the download link below the inline display, it will need to have its extension changed back to .bmp to display on our computers. This is a cheat though and overrides Stefan's restriction on uploading .bmps... but it does work.

But what you describe can't be the ultimate reason, because I use the same process and the same screenshot pilot program myself to make screenshots of my old Link DSO, saved as .png for upload here, and I get images that look like this 40 kb image: (a screenshot pilot grab of the DSO window):

[TinselKoala]

Here is a zip of the original file.

BTW, the load is 15 Ohm 1% 50w resistors connected to 3 Series 12v batteries at 37 volts DC, so no error on power to the load.

It's 1:25am and been a long day, so I'm closing up for the night. I'll pickup more of my 12v batteries from storage tomorrow so we can see how far we can take this.

Stay tuned and please try to find the error as this is too simple!

Luc

I don't know where the error is, but I see now why the scopeshots are so pixellated, the scope is set to save them at 320x240 resolution. And from looking at manuals it seems that might be as good as you can get. Maybe Poynt99 can give some advice as to how to get better resolution.

Sorry for the distraction, it's not really important, just hard for my old eyes to read your images especially with a lot of cycles and traces displayed.