Welcome to TEN350.com

If you've been involved in lightning protection in 90% of the world's countries, you've probably had the concept of the 10/350 waveform foisted upon you. What you may not know is that its origins have been hidden, its significance misrepresented, and its lack of workability casually ignored. We invite you to find out more..

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Let's just say there's been some exaggeration...

The claim that the 10/350 waveform is the truest, best, and only representation of direct lightning is an urban legend about as true as the one about the moon being made of green cheese. This...

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10/350 waveform caught in the act with no place to hide

The saga of pole-mounted transformers testifies to the bankruptcy of the 10/350 waveform theory and demonstrates the spark gap's inability to handle direct lightning..

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How is the 10/350 waveform related to this disaster?

Around the world and in every industry thousands of incidents have occurred where lightning has damaged electronic equipment being "protected" according to standards based on a 10/350..."

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Top lightning scientists pull plug on 10/350 waveform.

In 2013 CIGRE work group C4.407 released the results of a 5-year lightning parameter study. The report (Technical Brochure 549) invalidates any legitimacy the 10/350 waveform was ever thought to have had...

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Who gave life to the 10/350
test waveform?

It wasn’t Thor or any other god of lightning. It wasn't CIGRE. It wasn’t even the acclaimed Swiss researcher, Dr. Karl Berger. The answer may surprise you...

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How well do IEC lightning "protection" zones protect?

What are lightning protection zones? How effective are they? How badly are they infected by the 10/350 waveform? Read how they started...

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IEC lightning protection standards crumbling...

With the 10/350 waveform rejected, a major reform of the IEC lightning protection standards is imperative. Read here how the 10/350 waveform came to infect so many of the central aspects...

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What's a spark gap SPD?

A spark gap is a surge protective device capable of passing an IEC Class I test (10/350 waveform impulse.) That is the most charitable thing you can say about it. Its slow response time, high let-through current, and explosive emissions make it a poor choice for protecting electronic...

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Good news: Lightning protection can really work!!!

Effective lightning protection strategies exist. They don't have to be reinvented. Standards writers now have the chance to harmonize lightning protection guidelines with proven, workable practices ...

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SPD test based on CIGRE-authenticated parameters.

CIGRE kindly gave us some new and reasonable guidelines that could be used as the basis for testing SPDs. Needless to say, they have nothing to do with 10/350 waveforms. The parameters include...

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SPD Challenge

....you are being challenged !!!....

With the 10/350 waveform and Class I test requirements debunked by CIGRE's 2013 Technical Brochure 549, SPD manufacturers will no longer get much mileage from the slogan: “we can pass a 10/350 test.” 

Spark gap manufacturers will now achieve credibility only by demonstrating that their SPDs can stand up to and protect electronic equipment against the parameters of actual lightning.  There are two options available to them. The question is: which spark gap manufacturer will be the 1st to rise to the challenge?

Read More About the Challenge

Ten350 Forum

The Ten350 website has been set up to examine the credibility of the 10/350 current waveshape that was invented by IEC TC81 (Lightning Protection) and used in standards developed by IEC SC37A (Low-voltage surge protective devices.)

The pes-spdc.org website is warmly thanked for creating a discussion forum on the TEN350 site content. This in no way implies endorsement of the TEN350.com website by either IEEE or the PES Surge Protective Devices Committee.

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