The eighth webinar of a series "Grounding and lightning protection: issues and problems arising in the design"
Webinar text. Page 3
Quick navigation through slides:
1. How effective and feasible are ESE lightning rods
2. Seminar task
3. Regulatory framework
4. Is it possible to control lightning trajectory?
5. Basic phases of a counter discharge
6. Is it easy to shift corona into a streamer form?
7. When will sustainable leader appear?
8. Pulse duration
9. Energy intensity of the managing source
10. Implementation of the managing source
11. High cost of high-voltage source
12. In a manifold example, corona produces one order less
13. Increase of the number of corona centers doesn’t give any effect
14. Synchronizing block is not obligatory in ESE lightning rods
15. It is impossible to carry out synchronization on the charge growth on a cumulative
16. Problem of multi-component lightning
17. What do producing companies offer
18. How ESE lighting rods are tested
19. Device efficiency index
20. Experiment in ENIN in 1975
21. Experiments in “26 Central Research Institute” in 2014
22. Field observations
Ignoring" of ESE lightning rods - is it an occasion?
Упрочнение промежутка – gap reinforcement
Крутой короткий импульс напряжения может затормозить встречный лидер, а не ускорить его – Steep short voltage pulse can slow down the counter leader, not to speed it up
Largely speaking, the explanation was under our feet. The matter was this. Our institute had been working on one task many years ago. We wanted to see what would happen with high-voltage insulation, that is long air gaps if a strong and short high-voltage pulse would attack the front pulse of about 200-250 ms, it means the front which we are talking about. What did this attack do? Did it increase the gap strength or reduce it? Or maybe left it unchanged? The registrations were the most modern there. The laboratory was skilled in registration technique. We saw when such a pulse was attacking in the gap; there was a powerful streamer flash which emitted an immense charge, about 7 mCl into the gap. And when this charge was dropped, then the electric field on the top of this electrode dropped drastically and all ionization processes were finished. They were finished not looking at the fact that the voltage continued to grow. And it was required to raise the voltage up to 20% so the charge would go again and the gap was punctured. So the short managing voltage pulse not only did not increase he probability of a strike into the electrode, it reduces it. And this reduction of a number of strikes into an active electrode was observed by Reason, New Mexico and Kuprienko in his experiments held near Saint-Petersburg in 2013 and 2014. You see? The result turns out to be very simple and obvious.
If ESE lightning rod would function properly...
Традиционный молниеотвод – conventional lightning rod
Радиус защиты – protection radius
Радиус стягивания – contraction radius
ESE молниеотвод – ESE lightning rod
Прогнозная оценка – Forecast estimation
Радиус защиты – protection radius
Радиус стягивания – contraction radius
Если h =20 м то радиус стягивания ESE молниеотвода 300 м, что дает около 1 удара молнии ежегодно при n(m) = 3-4. If h=20 meters, then contraction radius of ESE lightning rod is 300 meters, which gives about 1 lightning strike per year at n(m) = 3-4
Организация полевой проверки элементарна- organization of field check is elementary
Now judge as you wish. I think that our lightning protection legislation is too gentle to ESE lightning rods. Our legislation says nothing about them. If means if you want to buy an ESE lightning rod. You can put an ESE lightning rod in your house for example. And if you count protection zone without consideration of ESE lightning rod action, nobody will raise you any claims. But maybe this is not correct? Look, an ESE lightning rod reduces the efficiency of lightning contraction due to its activity. It means that the use of an ESE lightning rod in the form they are made today reduces their protective action. And it seems it should have been reflected in our Russian legislation. And now I come to the part of the message which concerts the following. What would happen if an ESE lightning rod functions properly? I believe the company, I know it never lied to me, I put an ESE lightning rod in my house and hope that everything will be fine. See what will happen. Conventional lightning rod protection radius is a figure which is equal to its height on the ground level. And a conventional lightning rod contracts lightning from the radius of three heights as usual. It is a known figure which is accepted in the whole world and is confirmed by all the standards. If these correlations are the same precise for an ESE lightning rod, then it will contract lightning from its three radii, but the company states its protection radius is 5 times larger. It means this protection radius will become five times larger too. And instead of 3 heights, we will get 15. If I take a conventional lightning rod 20 meters high and suppose it contracts lightning from the radius of 15 heights, that is 300 meters, I will get the number of strikes in the regions with the average intensity of thunder activity grow to about one strike per year into my lightning rod. One strike a year, instead of one strike in 15-20 years like in a conventional rod. What's this? Is this good or bad? It is very bad, because lightning flows through this lightning rod, its current flows, all electromagnet impacts remain unchanged, and these unchanged electromagnetic impacts from a near lightning strike will annually affect my object. This shall not be allowed. If ESE lightning rod functioned properly, I would not put it on my house. But if ESE lightning rods functioned properly, then any company that manufactures them, would have a 100% possibility to check the efficiency of the lightning rods they produce. Look what we are talking about. All the companies which promote their products name the figures of lightning rods, which they produce. These figures are dozens of thousands of pieces. If such an ESE lightning rod contracts lightning from such a large square, then each ESE lightning rod would accept about 1,2,3 lightning strike depending on height. And then a simple lightning counter installed into this lightning rod would prove if it is efficient or not. The statistics would be instantly collected. And what is a simple device for registering lightning strike fact. Magnet register is the simplest device and it costs about a rouble per piece. If you want some simple automatic device, it will cost dozens of roubles per piece. Today's lightning rods are sold at dozens of thousands of roubles. It won't make big difference to add another hundred to this price. And then if you are sure in your product, you can get undoubtful statistics how ESE lightning rods function. Unfortunately, no company in the world wants to do these things. This is the reality today.
This reality has another moment, which I can't miss. You see? Sale of ESE lightning rods is a very profitable product. Whether we want it or not, but the authorities which should not interfere into this business, they still interfere. It is a letter which I received several years ago, it is signed by the head of GosEnergoNadzor. In the letter I am notified to notify you that Mr. Head allows the use of ESE lightning rods of "FOREND" company on the territory of the Russian Federation. And he will make it on the base of the certificate of the company mentioned here. And this certification is made on the base of these French test methods which I showed you. And these test methods to the estimation of efficient action of these lightning rods do not have any correlation. Further in this email there are addresses where you can buy a lightning rod. I think I made myself clear. My point is based on the experimental and theoretical research which was held by a large community of specialists in Russia and other countries.
— Dear colleagues, please ask questions if you have any of them. At the present moment, Eduard Meerovich, there is a discussion on the topic is it possible or impossible to use this product in the European countries and in the USA and what important objects already have this lightning protection. They say, that the building of the European parliament, Notre-Dame de Paris have this kind of protection.
— You know what. I can place lightning rods anywhere. Please pay attention to the following thing. Notre-Dame de Paris is more than 500 years old. And for more than 500 years it has been existing without ESE lightning rods. And the fact that these lightning rods are installed on Notre-Dame de Paris doesn't prove anything in the part of their efficiency. Nothing happened without them and nothing will happen with them. You see the argumentation we have and which I am waiting from the companies is as follows. The object was standing without any lightning protection and nothing happened. I will put my lightning rods and maybe nothing will happen too, but it is not the proof of the product efficiency. It is possible to prove the efficiency of the product only comparing it to some analogue. If there is a comparison - we can discuss. But, for some reason, no company tries to show statistics of using ESE lightning rods compared to conventional ones. One of the people I am communicating on this work and who represents the company organizing the seminar asked me the same question twice. Is there no scientific article which would prove the efficiency of ESE lightning rods? I underline - a scientific article. I don't know any scientific article of that kind. If some of you has this article, please show it to me. So the question is: "we sold 68 000 of them" and so what? How many packages of hydrolate were sold? And how much medicine for losing weight is being sold today and advertised on the Internet? Is it the proof of this medicine efficiency? Quantity gives nothing. Only qualified comparison does. And there is no comparison now.
— Yes, your today's report was comprehensive, because there are no certain questions at the moment. The only question o the previous webinars. If there are no questions, I can ask. It concerns step voltage, appearing at a lightning strike, and how long it stays on the ground - step voltage?
— I understand that the question has no relation to ESE lightning rods, but I am happy to answer it. The matter is in the following. Step voltage exists for the time during which lightning current flows. If you have one lightning current pulse, then the average duration of this pulse is equal to 0,5 and it lays somewhere in the range of 100 ms. And in 200 ms from steel voltage, there remains about 15-20% of its value. But if lightning are multi-component, several current pulses will flow either by the same channel and in case of impact, there will appear inter-component pauses with corresponding intervals. The average pause between the components is 70 ms. And the next step voltage will appear with the pause of 70 ms from each outsurge. Collectively, the ultimate number of these flash goes up to 30, and the summary duration of all of them - about 1 s. It means during 1 second in an ultimate unfavourable case a person can be under a dozen, or two dozens of pulse voltages. That's the situation.
— Please repeat the information one more time, is it possible to consider the reliability of an ESE lightning rod similar to the reliability of the passive one?
— What I am saying? First of all, what advertising prospects say? The advertising prospects tell if you put an ESE lightning rod on your tower, to the rod lightning rod, the protection zone of this lighting rod increases in 5 times. The advertising of the companies tells this. What does our Russian legislation say? It tells nothing about ESE lightning rods. What does the International Electrotechnical Commission Standard say? Nothing, either. It is silently supposed that if you put an ESE lightning rod on your device, you have to calculate protection zone of this lightning rod as if you don't have any ESE lightning rod at all. According to our legislation, there are no ESE lightning rods at all. I start to doubt that, because the experiments held with the ESE lightning rods manufactured today say that their protection zone can reduce due to the effect which I showed you. No legislation, neither ours, nor the legislation of the International Electro technical Commission, nor the American standard has any orders on that issue. What I tell is my opinion.
— And the question. Can you comment on the protection zones by the opinion of ESE lightning protection manufacturers, where did they come from, to your mind?
— I would like to see some document from which I understood this method. I don't have it. You know, it is the style of some European regulatory documents. For example, International Electro technical Commission - IEC published its standard 62-305 in which the rolling sphere method is actively promoted. This rolling sphere method is getting into the Russian Legislation, whether we want it or not. It seems it will be advertised soon. There are absolutely no proofs under this method. I had a chance to meet one of the authors of this document and I asked him if we could show me his work with the base positions of this method. He answered he could not. But it is very beautiful to use rolling sphere radius. But beauty is not the point in this case. I don't know, I can't prove there these figures came from.
— While we are waiting for the questions, I will address to all the participants. You will see the link in the chat, please fill in the questionnaires. You can express your wishes there, ask your questions and put a mark to the today's event. Thank you for your participation.
— I thank everyone for the participation. You know if was quite hard for me. I tried to be very objective. But it's up to you to judge if I did it well. But the materials I operated with, are inviolable. It means all the experiments I referred to, were done in series with the number of measurements counted by thousands. The results of the experiment cause no doubt. The interpretation may cause doubts. But it's a natural thing, is not it? It cannot be any other way. But it is a fact that there is no direct proof of efficiency of ESE lightning rods. And it is also a fact that there are proofs of doubts in their efficiency. And we had to study that. That if why I am very much looking forward to meeting creators of ESE lightning rods. If this meeting takes place and the results are put on the Internet, I think it will become clearer. But I have no doubt about what I've told you today. Thanks again for your attention!
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