Radio Receiving Antenna GEC Indirect Connection To Subpanel

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I-learns

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Something I saw causes me to revisit the theory of communications systems grounding. Isn't a reason you do not bond an antenna to a subpanel and instead bond to the main service GEC point so that you can reduce the chance that different voltages will set up throughout the building distribution system as the voltage from a static/strike drops while it takes the route to the grounding electrode system? If so then wouldn't it be a good practice to keep the antenna discharge unit seperate from the enclosure containing the actual radio, so that there won't be a connection from the antenna's coaxial shield to the equipment ground in the same enclosure that comes from a 120V power source for the radio?
 
Welp the article date is Cir 12' (I'm so dyslexic)
But the references are

[1] NFPA 70, National Electrical Code, National Fire Protection Association, 2011
[2] NFPA 780, Standard for the Installation of Lightning Protection Systems, National Fire Protection Association, 2004
[3] Silver, H., Editor, ARRL Handbook for Radio Communications, ARRL, 2012

Plus additional readings...
 
Yes I read that article from Mr Reeve, who is no longer with us. It’s really seems like there’s not enough authoritative sources on communication systems and the NEC, or the actual reason for some of the rules. I’ve taken Mike Holt programs. Learned a good bit but still wanted to understand more. I’ve learned that not knowing isn’t really that uncommon because there’s a lot of folks either not caring to know or just doing with the code says without understanding why.
 
I-learns said:
Yes I read that article from Mr Reeve, who is no longer with us. It’s really seems like there’s not enough authoritative sources on communication systems and the NEC, or the actual reason for some of the rules. I’ve taken Mike Holt programs. Learned a good bit but still wanted to understand more. I’ve learned that not knowing isn’t really that uncommon because there’s a lot of folks either not caring to know or just doing with the code says without understanding why.
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Some things in the code there is no real understanding why because it is so arbitrary.

A lot of the code seems to have been written so it is deliberately not understandable.
 
petersonra said:
A lot of the code seems to have been written so it is deliberately not understandable.
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I get a bit upset sometimes over the insistance on "the Code is not a guide for untrained persons" that comes often as a defense and/or reason to refuse to improve each time they add some failed language that an electrical professional would have difficulty properly understanding.
 
LarryFine said:
Why intentionally bring a lightning-current pathway into the structure?
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Wouldn't want to do so. But if seeing something installed, the question might be more of: is it prohibited, or: is it clearly against the intent of the standard(s), rather than is this the way I would like to do it.
 
I-learns said:
Wouldn't want to do so. But if seeing something installed, the question might be more of: is it prohibited, or: is it clearly against the intent of the standard(s), rather than is this the way I would like to do it.
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The GEC is always connected to the EGC so no matter what you do there is a path for lightning to come inside. It's just not the path you're thinking about.

in any case, if you have a direct lightning strike the GEC is not going to protect you. That is a longstanding myth that you would think somebody would have gone to a lot of trouble to kill off a long time ago but there are still a lot of otherwise good electricians that believe that somehow the GEC being connected to Earth will protect you from a lightning strike.
 
petersonra said:
1. The GEC is always connected to the EGC so no matter what you do there is a path for lightning to come inside. It's just not the path you're thinking about.

2. in any case, if you have a direct lightning strike the GEC is not going to protect you. That is a longstanding myth that you would think somebody would have gone to a lot of trouble to kill off a long time ago but there are still a lot of otherwise good electricians that believe that somehow the GEC being connected to Earth will protect you from a lightning strike.
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1. Yes they are connected but if there's a bond from the coaxial shield/discharge unit to the building's GEC and not also to the ECG of a sub panel, then it would seem that at least there isn't a parallel path to the building's GEC through the building's distribution system.
2. Yes I am aware that correct bonding would require connection between the 2 systems, not just connection of the coax to some random ground rod.
 
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