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Discussion Starter · #21 ·
I know you asked this over at Holt's. I don't remember if it is Dennis (moderator here also) but there are a couple of guys who interact with the Code making panels. I can tell you that it's been that way so long there may not be any history on it.
So are those guys who interact with the Code making panels still on either Holt's or Electrician Talk?
 

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But this is only in practice though. In principle, there is no risk at all if no one ever makes a relevant mistake. That is evidenced by pilots of most airlines and train drivers in Japan, where no pilot/driver ever makes a critical mistake outside of freak events.
Years ago you could get away with using the structure as a ground then along came vfd's and switching power supplies which makes the whole idea of using the building as a ground path mute.
 

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Discussion Starter · #23 ·
Years ago you could get away with using the structure as a ground then along came vfd's and switching power supplies which makes the whole idea of using the building as a ground path mute.
Then show me the range of values of impedance for typical buildings for the frequencies that the VFDs and SMPSs operate at. Due to the large surface area of building frames, they shouldn't have a high impedance due to skin effect because the surface area of the beam that a VFD would have been attached to is still many times greater than that of a single stranded conductor.
 

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Discussion Starter · #24 · (Edited)
forgot about him !!!
im not sure he is up to this level of research, but if he is, then he is even more knowledgeable than i thought
I am up to that level of research, which is why I'm asking. I am only asking to see how the rule applies in uncommon cases. If the wording of the rule were logically complete and deterministic for all possible cases like models in hard science, including cases that haven't happened yet, then I wouldn't be asking. The fact is some of the provisions in the NEC do not give a definitive answer. So, I'm only asking to see if i could get a unanimous interpretation that clarifies (makes more precise, ideally exact) the provisions of the NEC.

Even though any model that deals with the world may be wrong (defined as not matching the data), all hard science models at least give a deterministic answer to be able to definitively support that model or disprove it immediately. If even a single non-erroneous measurement is not agreed with by a hard science model, it immediately means the hard science model is wrong. The hard science model then has to be modified to fit that measurement.
 

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I am up to that level of research, which is why I'm asking. I am only asking to see how the rule applies in uncommon cases. If the wording of the rule were logically complete and deterministic for all possible cases like models in hard science, including cases that haven't happened yet, then I wouldn't be asking. The fact is some of the provisions in the NEC do not give a definitive answer. So, I'm only asking to see if i could get a unanimous interpretation that clarifies (makes more precise, ideally exact) the provisions of the NEC.

Even though any model that deals with the world may be wrong (defined as not matching the data), all hard science models at least give a deterministic answer to be able to definitively support that model or disprove it immediately. If even a single non-erroneous measurement is not agreed with by a hard science model, it immediately means the hard science model is wrong. The hard science model then has to be modified to fit that measurement.
what we say wont matter, it will be what the ahj says because his is the final word any time he chooses, unless you can quote him a code that makes him wrong
if you will look long enough , you will find a place or two that say the ahj has the last say
what were you gonna tell him ? the guys on ET said it should be this way ???
 
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