Xedge chill out and open your mind for a moment than you are free to respond.
No one has said those PEs you listed are wrong.
What I believe is you are misunderstanding what they are telling us.
For the most part when these PEs say 'grounding is critical' they are not talking about the connection to earth but the interconnection of the EGCs.
The only time a connection to earth may help a TVSS is if it is dealing with a lightning strike.
All other transients must go back to the source which is not the earth.
You are correct there are MOVs from line to ground.
You are mistaken as to which way those are directing current.
Those line to ground MOVs direct transients on the ground to the line and back to the source.
If you tried to direct a utility supplied transient to 'earth' all it would do is find its way back to the source through other grounding electrodes. It is more efficient and of less impedance to direct it right back to line.
Anyway, that has been my understanding of TVSS operation and I have installed a few
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myself.
A simple question.
Would you say a TVSS installed in an airplane would not work as there is no connection to earth?
Bob
[This message has been edited by iwire (edited 01-03-2006).]
