After almost 30 years of watching lightning strike the CN Tower, a University of Toronto professor says his work may hold the clues for improved power protection in IT equipment.
Professor emeritus Wasyl Janischewskyj originally
set out to better protect power lines when he began using the world’s tallest freestanding structure as a research tool in 1976. After collecting and analyzing his data, however, Janischewskyj said he believes his measurements may help vendors figure out the most effective procedures for protecting sensitive technology in tall buildings as well.
“”The idea is that we would be able computationally to predict the radiation,”” said Janischewskyj, whose work was recently published in the Journal of Electrostatics. “”Then we would be able to tell manufacturers of various pieces of equipment what kind of precautions they need to take, like enclosures in metallic structures or in plastics sprayed with a metal outside.””
At first, Janischewskyj and his team would put small resistors on the lightning strips that run along the tower’s surface and attempt to measure the voltage across it. This would provide the value of the current, he said. He soon found that a better method involved putting a coil around the steel structure at the top of the tower and measure the voltage induced in the coil.
Lightning strikes the CN Tower about 75 times a year, and Janischewskyj and his team have been spending close to three decades measuring the rate of change in the current.
“”At first we only recorded the current,”” he said. “”Then we found it is also of importance to record the electromagnetic field. That was the next step, in the early 90s. Then the improvement in the equipment that has taken place in the meantime has brought us to this more advanced measurements in place.””
Janischewskyj hopes the patterns in the way lightning strikes will create models that improve the ability of encloses and power protection products to deal with sudden spikes in voltage, which can cripple IT equipment. He said the tower’s unusual structure, with its Skypod and observation deck, obstructs the downward flow of electricity and causes the current to peak in certain areas. Identifying such patterns is critical to designing protective measures, he said.
Surge protection remains a major priority for all kinds of businesses in Canada, said Bill Black, president of Wilcan Electronics Canada Ltd. in Brampton, Ont. The spread of IT outside the enterprise, meanwhile, has created new market opportunities.
“”Two years ago we started to serve the domestic market,”” he said. “”We have a home protection system consisting of a unit that goes on the electrical panel, another that goes on the phone line if they’re connected to the Net, and another protector that goes on their signal line.””
Janischewskyj said his work is ongoing, given that the most important tool in his research isn’t going anywhere anytime soon.
“”(The CN Tower) was an ideal place to put some measurement of lightning because it attracts relatively a large number of strikes per year,”” he said.
Janischewskyj ‘s study was funded by the Natural Sciences and Engineering Research Council of Canada.