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Ask Slashdot: Best Option For Heavy-Duty, Full-Home Surge Protection?
First time accepted submitter kmoser writes "Like most people, I have a couple of surge protectors for sensitive/important electronics, and even a UPS for a couple of items like computers. But I don't have surge protector on all outlets, and these consumer-grade devices don't cover things like 220 volt appliances. Add to that the fact that I live in a lightning-prone area and it's only a matter of time before one of my expensive devices has a major meltdown. I've looked into full-home surge protectors that install next to the fuse box but the prices vary widely and I have no idea how reliable they are or what brands are good. An electrician friend tells me they can still blow out, and when they do they're difficult to replace if they were installed behind a wall. Can anybody shed some light on the best options for protecting all the electronics in my house with a single surge protector?"
Not at all. Parent post suggested a second option: Insurance. One option is to try to make sure nothing ever fails. The second option is to assume that things will fail, and have a recovery plan. This is a vaild suggestion.
You don't install surge protectors to defend against a direct lightning strike --- there is no real defense against a direct lightning strike - you can make it less likely with a well-engineered lightning rod protection system.
You install surge protectors to defend against currents induced by nearby lightning in your wiring. This is protection against damage lightning can cause without actually striking your wiring, or your building. If lightning strikes a mile away from you, and hits the ground, or a tree: this lightning can still induce currents in unshielded underground and overhead power and data cables. If there is no surge protection, the induced currents may destroy sensitive electronics such as computer power supplies.
In a direct hit situation, lightning hitting a surged protected circuit can easily arc through any surge protector; human safety is paramount in the design of surge protection and electrical systems, anyways, so there are always compromises anyways, that is, surge protectors still share a common ground with everything else, and a direct hit clamped to ground can effect everything else tied to that ground --- Remember, with resistors in parallel, the amount of current is proportional to the resistance - the amount of voltage passing through the higher resistance path is not zero. Even if 99.9% of the lightning strike is clamped to ground, the 0.1% can still be 10000 volts.
No commercially available surge protector apparatus able to be fitted to a home electrical system and other utility lines entering a building with a price that is remotely affordable to the average homeowner is capable of providing remotely robust protection against a direct strike.