Sunday, June 10, 2007


Let's hope this isn't necessary detail at this point in the summer - I would have posted it earlier but it was just added to a forum I look at. Don't know about you, but we have our computer on a brickwall filter which claims to stop damage from lightning (ZeroSurge). Many of the power strips you read about or see at Target or best Buy aren't likely to work, sorry to say. I've seen good devices run from a couple hundred to several thousand dollars.

I have some of my audio gear on a sacrificial circuit (box) which would give itself up when necessary. Same with the TV.

Apparently one of the surge problems is when the electricity comes back on. It's a good idea if we have a blackout/power failure, to turn off your computer (or unplug it) and also the $5000 tv.

Here's the entry:

Spent many years in the Southeast working for one of the now-large computer companies. As a hardware repair guy, I dealt with many, many weather-related issues and electronic equipment. Here are my 20+ years of observations:

* Lightning is fickle: I've seen direct hits to buildings not necessarily wipe out everything. In fact, I've seen failure of one rack of gear in the middle of a row of racks! A lot depends on the quality of the grounding system in the building and how well the individual wire joints have continuity and, of course, how exactly the lightening made its entry.

* There are many ways for lightning's effects to enter a building: For most residences, there are 3, maybe 4, specific ways electrical energy from lightening can enter: Your main electrical feed, your cable system, your telephone system and any antennas you may have erected around the house. All, or any combination, can deliver the punch your gear can 'feel'. You *must* have solid and reliable grounding systems in place to help mitigate the effects of lightening on these entrances.

* Failures are not immediate: Sudden electrical surges, combined with any number of potential ground loops, poor or non-existent residence grounds, coupled to poorly-maintained electrical distribution will manifest itself in stressed components. That is, there are all kinds of reasons why the gear in the house is stressed but not to the point of specific failures of a component as the surge happens. I've seen multiple failures across days and weeks, depending on how long it is in operation, the amount of ambient thermal heat involved and heat-up/cool-down cycles involved. In other words, if you've had a hit and lost a couple of items, you *may* have more failures.

* Don't forget the electrical distribution system: Mentioned above, the quality of your home's electrical, cable and phone distribution system goes a long way to dissipating that energy that we tend to lump into the term, 'surge'. How well that extra energy is bled off to ground is really important. Most folks do not have their electrical system shut down and the joints throughout the house cleaned and retightened to proper torque spec, even though this is a common practice in most manufacturing environments. For this reason, purchase of much of the add-on power conditioning equipment marketed to the consumer today isn't really valuable unless the rest of the distribution system is up to spec. Don't mistake me, these devices have their place and can be valuable but they depend on your house's electrical system to be up to spec to have any reasonable effect.

So, short answer to your question, "did the lightning you observed and the consequential failure in the neighborhood cause a problem for you with your power bar in the line?" is: It depends.

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