Cranked up the generator to 6.5KV 40uS into an open using the 2 ohm source. The waveform is attached. This is about 700 volts over what I had the two final meters at. I then repeated the test using the Fluke 101 all modes, both +/-. Once again, the Fluke remains fully functional. The more I beat it up, the more impressed I am.
This really is the limit of the generator. There is no room inside to add more storage and pushing it harder is just going to damage it.
What voltage are the caps in your bank rated for? Couldn't you charge them with the output of that neon sign transformer that you used for your Jacob's ladder? That way, you would need to get your internal DC converter to put out a higher voltage. You would just need to limit what level you charged the caps to.
The caps (storage) are the limiting factor. Are you going to run the 101 on your 12KV setup?
The 101 arrived, and I tested it after I got off work.
The unit survived the full 12kV!! I hit it 3 times, each polarity, on all switch settings. Everything was fully functional, as I tested every single position.
I actually started at a lower level, an not right a 12kV. I hit it 3 pulses of each polarity at 6, 8, 10, and then 12kV. After the Fluke passed all of that, I blew up another $5 Harbor Freight meter, just to prove to myself everything was working.
I recorded the testing, but there is no point in posting it, as NOTHING happened.
I also took a short video of the inside of the surge generator, so everyone can see it's construction. I'll post a link as soon as it finishes uploading.
I was afraid of that! Fungus called this one!
So we are all clear, I have a few questions.
Are you using the 1.2/50 8/20 surge, 2 ohm source?
Was there any sort of bias on the meter when you hit it with the transients?
Did you verify the waveform?
And of course, what's it going to take to damage one of these!!?? It's a cheap $50 meter, how hard can it be??
I was afraid of that! Fungus called this one!
So we are all clear, I have a few questions.
Are you using the 1.2/50 8/20 surge, 2 ohm source?
Was there any sort of bias on the meter when you hit it with the transients?
Did you verify the waveform?
And of course, what's it going to take to damage one of these!!?? It's a cheap $50 meter, how hard can it be??
Yes, it was a 1.2/50 8/20 surge. That is the only wave this machine does, as it was designed exclusivley to test 61010-1.
No bias. I am looking into a CDN, but do not have one yet. I doubt a bias would have done anything, as there was no arcing at all during the surge testing. Yes, it would add continuous energy after an arc started, but I don't believe there was any arcing.
I did not verify the waveform. I do not have a high voltage probe for my scope. But, this machine is calibrated, and the waveforms verified during calibration.
It looks like Fluke may be true to it's claim that these meters will survive upwards of 17kV. I'm going to open the Fluke, and see what MOV's they are using, and what type of capacity they have. Maybe they can clamp these levels. It looks like someone my need to build a 20kV generator, or increase the length of the pulse to kill these with a surge.
What sort of rep rate were you hitting it at?
The video of me hitting the 12kV was a total of 12 minutes long, with all the pulses as described above. If I have time this weekend, I will move it off the GoPro camera, speed it up so it's not 12 minutes, and post it. It just seems like a waste, because it is just me changing dial positions, and hitting the discharge button. No good blast to see, or hear.
Good luck with your 10kV testing (looks closer to 12kV on that waveform). Based on my testing, you will be quite bored.
Guessing that was a custom unit for Fluke.
Joe,
I looked back at that document you posted on page 2 of this thread. It was from Advanced Energy on building and testing surge generators. That document shows the pulse length markers from the 50% amplitude on the rise, to 50% on the fall. It matches the waveform from my generator dead on.
If you look at your latest waveform compared to that document, your decay pulse is more like 20 uSec, instead of the 50 you want.
They use FWHH to measure peak shape. I am using the 100/0 which I thought was very clear from all of the scope shots. But then I have made statements about how it compares with 61010 so I can see how I clouded things up.
Still it's not a big deal. I'm starting to sound a bit like a broken record but again, I was not too concerned about what I hit the meters with, as long as they were all tested the same. Again, I am not trying to certify the meters for CAT III.
Guessing that was a custom unit for Fluke.
Found what looks to be that model on-line. The specs say it can go to 33 kV, and deliver 30 kA. I don't even want to know what a machine like that costs.
I think the 30A 8KV system we looked at last was around $80. The 16A 2-phase 8KV system I am looking at now is around $30. For non-certified, home project stuff, what I have is fine.