On Mon, 2 Nov 2009 11:20:22 -0500, Paul Christensen wrote:
>> They are almost certainly MOVs. Shunt mode surge suppressors (MOVs) on
>> branch circuits are a very bad idea --
>Jim,
>Even with primary suppression protection at the service entrance? The
>literature I'm seeing suggests the use of secondary suppression on branch
>circuits *only* after the inclusion of primary protection at the service
>entrance exactly for the reason you mention.
Yes. Think about it -- even without suppression at the service entrance, the
neutral must be bonded to earth, which limits common mode to what is picked
up on interior wiring. IEEE data says that 3kV is a reasonable rating for
branch circuit products, and SurgeX builds (and tests) their series mode
suppressors to this level.
I see MANY posts about folks losing computer networking gear to lightning.
This is nearly always the mechanism that does it.
73,
Jim Brown K9YC
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160 meters is a serious band, it should be treated with respect. - TF4M
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