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January 1998, Issue 90

Ground Zero:
A Real World Look at Lightning


by Steve Ciarcia & Jeff Bachiochi
Start It's All in the GroundingTransient Voldatge SupressionModem and Power-Line ProtectionUnplug the Computer! Automatic Thunderstorm Switch Black Box It Waiting for Summer Sources

UNPLUG THE COMPUTER!

The absolute best way to protect equipment from power-line, phone, and cable surges is to simply disconnect it when not in use. This seems obvious, but it’s a nuisance having to plug and unplug entertainment centers and computers. It’s only after you’ve had major damage that such inconvenience seems like a viable alternative.

Jeff is aware of my situation. I suspect that the reason he has lightning rods installed at all is from hearing my horror stories.

Unfortunately, while the concept is sound, implementation isn’t that simple. Jeff has a big family and just can’t unplug everything when he leaves for the office.

I have the luxury of unplugging the simple stuff like TVs and stereos, but devices like time-lapse recorders, auto-answering computers, and fax machines can’t just be left unplugged. The optimum situation would be to unplug the equipment automatically only during dangerous conditions. When the storm passes, connections are restored.

We’re aware that commercial devices exist to do this task. Unfortunately, their lofty price leaves them in the category of airport landing systems.

Without a source for a reasonably priced "thunderstorm switch," Jeff and I decided to make one. Conceivably, all it would take is a lightning sensor, decision logic, and a means to connect and disconnect the attached equipment.