Jim Lux wrote:
>There is a case where they will be of less effectiveness.. if you have a
>transient induced on the branch circuit between the panel and your load,
>then the transient propagates both directions, and, depending on the
>relative lengths of the wire, it will get to the load before it gets to
>the clamp. Once the clamp goes into effect, an inverted transient gets
>reflected back, so you can calculate the maximum width of the
>unsuppressed pulse. (you could use something like 2 ns/ft as a
>propagation speed... so for a 100 ft run, with the transient induced
>next to the load (or downstream from the load), you get half a
>microsecond or so before the voltage is clamped.
And it's even worse in situations like mine, where the whole house protector is
attached to the main shutoff next to the meter, but the circuit breaker panel
30 feet away in an interior room.
I use a Panamax gpp8005, by the way. So far, so good.
After two hits at this QTH, don't get me started on all the insidious ways that
lightning can get inside ! If you think you are protected by having a
well-grounded tower and a few Polyphaser's, you're dreaming.
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