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Posted By: ayrton Article 250-52 - 01/08/02 03:52 PM
In the Technical Licensing Studies Work book for passing the State Exam it has a question regarding lightning rods. "Electrical equipment shall be kept how far from a lightning rod before it must be grounded to the rod?"
It than gives you the answer where to look in Article 250-52.
In the NEC 96 code their is no article '52'
It goes from 250-51 - 250-53.
In NEC 2002 their is an Article 250-52, but no mention of the word 'Lightning rod'.
Is this exam question regarding a grounding electrode or lightning rod. I was under the impression that a lightning rod is to protect a structure form a lightning strike. Am I wrong? Any input would be appreciated.
Posted By: Elzappr Re: Article 250-52 - 01/08/02 04:43 PM
250-46 in the 96 Code.
250-52 & -106 FPN No.2 in the 99 and '02 Code.
Basically 6 feet..or else the lightning will jump from the "air terminal" ground electrode conductor to other ground electrodes or surfaces..increasing likelihood of burning things. Look in the index for "air terminals" (not "lightning rods"). Also, the ground electrodes for the air terminals need to be AT LEAST 6 feet away from other building ground electrode rods in order to effectively and safely dissipate the lightning charge.
Posted By: resqcapt19 Re: Article 250-52 - 01/08/02 06:15 PM
Note that NFPA 780 (Lightning Protection Code) requires that the lightning protection system grounding electrode system and the electrical system grounding electrode system be bonded together.
Don(resqcapt19)
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