IEC 60052 Voltage Measuring

[Jason C Wells]

I attempted to do a rod gap measurement on my VDG per IEC 60052 and got a tiny gap. I can pull a 4 inch spark easily with a 4 inch spherical grounding wand, though.

A key thing that I wonder about the rod gap test is the requirement that the test apparatus must be 4 meters from any surrounding structure including the floor. I just don't have that kind of space. I don't need the 3% accuracy that IEC 60052 delivers.

Have you done IEC 60052 rod gap voltage measurements? Is this something for hobbiest to attempt in a small garage?

And just for fun:

https://www.youtube.com/watch?v=2KA5L6XOvZw

It looks like their machine has some stored energy. I'm glad I don't have that monster at this stage in my learning.

Regards,
Jason C. Wells

[Dennis P Brown]

This has been discuss in previous threads but the key is that one needs to use two spheres that are very similar in diameter (a rod end isn't going to do that at all. Rods will leak current away and lower voltage of the VdG sphere. That is why your 4" grounding sphere produced a much higher spark length.) The 4 meter clearance is a bit of a red hearing since few rooms would have dry enough air to make this relevant, in my opinion. Four inches isn't too unusual and I've manage six on good, dry days but my current is lousy; again, voltage isn't really the issue for an accelerator (why? Anything over 75 kV is going to do fusion; of course, higher voltage is better but that also leads to more likelihood of shorting) but getting significant fusion requires current; also, if your system is leaking current for any number of reasons the voltage will always be low.

I spent a lot of time adding/adjusting/modifying types of ways to increase current of my commercial unit and frankly, they didn't help at all. Maybe bad luck but not so sure - issues of dust and moist air and units having too small a belt can't easily be fixed.) Belt width is the key (as Richard pointed out to both of us in posts) and I intend to make a 6" wide belt. Aside: Belts are really easy to make; to make the VdG unit I intend to use a belt sander for parts (most of what you need is there already; bearings/rollers/adjustment hardware for rollers, motor & drive system) with the sphere halves I have (and modify into a long sausage type dome) should require little more heavy work. Add a simple 25 kV positive spray and hopefully, a high current VdG with the correct polarity (don't want to accelerate electrons!)

For accelerators, current tends to be the issue - really high voltage will cause even more current to short! So aiming for just high voltage may be self defeating.

For a really good VdG design (high current with polarity spray system), check the wiki site under VdG; very simple design there (photo's) that use two sphere' halves and a center semi-cylinder.

[Jason C Wells]

So the rod gap test is inappropriate for VDGs, even if they are DC. I hadn't considered that from the outset but it seems obvious given my results and your comments.

I don't recall the spec saying anything about current or capacitance. IEC 60052 is geared toward power transmission equipment, not science projects. I didn't do the test poorly. The rod gap test doesn't apply to my equipment.

Going back to the video, it would be an extremely well driven VDG that could sustain that current.

Thanks,
Jason

[John Futter]

Jason
You might want to make a field mill to measure your voltage
this is how nearly all professional VDG's do it
more here
http://freespace.virgin.net/paul.zimmer ... #Measuring

[Jason C Wells]

I know someone who has scavenged a field mill of unknown functionality. I might have to talk to him. Thanks.

Jason

[Richard Hull]

I have just posted on much of this in another of your posts in this forum today, check that response out. I am happy to see that you and Dennis are farting around with VDG's. Something may yet come of the effort in amateur fusion. I am sure it will be a rather difficult path as static machines are balky and often quixotic as Dennis has discovered over the last few years. I learned this early back in the 1970's. You are rather at the mercy of the environment, moment to moment, where a wall outlet driven system is not.

Richard Hull

[Jason C Wells]

I've heard what you've had to say too. I often don't get the application of the advise until after I do it. Then I say, "That's what $person was talking about."

I never did post about my aborted pelletron effort. I tried to make one. It actually made sparks, in all the wrong places. Off to read the other post.

Jason