electrical interruption

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w_tom wrote:

In troubleshooting the computer damage years ago I found the phone and power grounds unbonded. I bonded them because I'd known for 20 years that bonding was required. I thought the lack of bonding was rare until I talked to a telco man five years later. Still later, I read at the Zero Surge site that the lack of bonding is a common and serious problem. BTW, did you know no computer plugged into a Zero Surge protector has ever been damaged?

No damage to a protector. There was no plug-in protector for my TV and stereo. I had foolishly trusted my whole-house protector.

Don't you think there would be a lot more damage in this neighborhood if the power company's lines weren't grounded?

I wonder why I didn't see your question before. It's not buried in the ground, but of course it's connected to the same neutral bar as the power company's ground wire, eight feet from my ground rod.

Most buildings are like cows in that multiple grounds are inevitable: water supply, water drain, furnace, construction materials, power tool lying on the ground. Your single-point theory has led to thousands of deaths when people touched objects like faucets and phones during thunderstorms. A building needs bonding. Sometimes it needs multiple ground rods.

Does electricity always choose the longest path to ground? Except the rabbit ears, the only conductors within several feet of the TV were the hot wire and the neutral. So now you're telling me the surge came in through the plug and exited through a lightning bolt? I was watching the TV. I saw no spark at all.

I'm the one who has been saying earthing had nothing to do with that incident. Unbonded grounds had zapped a computer and modem years earlier.

Back to ground through the breaker box. That's where current flows through all my neutral wires. Aren't your neutrals hooked up?

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Speculated only (without any numbers) that all wire is perfectly conductive. An effective protector is earthed via a 'less than 10 foot' connection. A phrase that has been repeated how many times? Eight? Ten? Thirty? Distance is critical because wires are electronic components - especially when discussing destructive transients that occur within microseconds.
Will that transient shunted by an adjacent 'plug-in' protector go to earth ground via the neutral wire? Lets assume a 50 foot connection to breaker box and earth ground. That means a 'so trivial' transient of 100 amps must transverse wire of less than 0.2 ohms resistance AND maybe 130 ohms impedance. 100 amps times 130 ohms is 13,000 volts. So the computer and adjacent protector are at something less than 13000 volts relative to earth. How can this be? Welcome to more electrical facts - especially earth ground - that plug-in protectors forget to mention.
You tell me. Is that transient going to use a 13,000 volt neutral wire? Or will it find other destructive paths to earth? Other electrical conductors include the table, linoleum floor tile, some wall paints, that baseboard heater. Stereo is wired to speakers. Those speaker wire touch what? Numerous conductive electrical paths may exist. Neither that TV nor stereo was connected only to hot and neutral power wire. A common destructive path through both would be incoming on either or both AC wires, and then outgoing on any one of so many other destructive paths.
If the transient only entered on AC hot and left on AC neutral, then internal protection inside both TV and stereo could have made that transient insignificant - no damage. But then Choreboy describes an electric circuit that entered on AC wire and exited somewhere else - as typically destructive transients would do.
Lets assume, anyway, that entire 100 amp transient does seek earth ground via the neutral wire. That wire is bundled with other wires. That transient is inducing transients on all other wires. What is connected to those other wires? Stereo and TV. Just anther reason why the plug-in protector was not effective.
The 'whole house' protector must make a 'less than 10 foot' connection to the same earth ground used by telephone, cable, and even satellite dish. You had a protector and suffered damage? Then a protector did not connect to a single point earth ground.
Do we dispute the generations of professionals who have proven the critical need for single point ground? Lurkers can access a list of industry professional citations at: alt.comp.periphs.mainboard.asus on 30 Mar 2005 entitled "UPS unit needed for the P4C800E-Deluxe" http://makeashorterlink.com/?X61C23DCA
Unfortunately Choreboy provides no technical basis for his assumptions. Multiple grounds are inevitable? Wrong. The entire earth beneath a building could be one big single point earth ground if we used what has long been available before transistors even existed - Ufer grounding. It means building new buildings as if the transistor existed. Other solutions are suggested by utilities in that above long list of industry professional citations.
In the meantime, Choreboy somehow assumes a plug-in protector is earthed by a grossly undersized product that does not even claim to provide that protection. He admits to multiple earth grounds but denies they can cause damage even though NIST figures demonstrate otherwise. He believes single point earth ground can be dangerous. He provides no technical reasons why nor even cites a single responsible citation or number.
He had damage. The transient found earth ground, destructively, via his stereo and TV because a human permitted a transient inside the house. There is no way around those facts demonstrated in a full day's reading from industry professional citations. The protection is only as effective as its earth ground.
Choreboy wrote:

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