said by Rhaas:Lutful, your drawing confuses me, correct me if I'm wrong but that is a 3phase diagram, is it not?
Method applies to any configuration which have incoming AC neutral and local ground at shelter. You can use the generic IEC diagram per DEHN in other thread.
FYI this diagram is actually Figure 6 from FAA STD 019 which was uploaded in other thread - you should read their suggestions designed for maximum equipment protection. I only added a few comments in blue text and showed the most critical N-G SPD which lowers the potential on both AC neutral and AC ground inside the shelter during a direct or nearby lightning strike.
said by Rhaas:I am pricing out a TVSS for the site but I don't know if they'll pony up the keesh.
The N-G and L-G SPDs for shelter AC panel should be tested according to UL 1449 3rd edition guidelines which requires 16 strikes of 6kV (8/20uS) surge waveform one after another. I think those devices are listed under "VZCA" class at UL database but you have to check test was done after Oct/2009 when lightning surge related changes came into effect.
Strikesorb is such a device and may not be that expensive - I like their claim to have invented the generic "V connection" shown in other thread. »
www.raycapinc.com/docs/d ··· tion.pdf 
