Lightning Protection wire req.

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I'm having to do a repair on a counter poise AKA (Lightning Ring) and the question is would using a piece of 2/o cu be excepted as equal integrity to the copper clad crap used by most Lightning protection contractors .. Code References of any sort or jurisdiction are cool...
 

mcclary's electrical

Senior Member
Location
VA
I'm having to do a repair on a counter poise AKA (Lightning Ring) and the question is would using a piece of 2/o cu be excepted as equal integrity to the copper clad crap used by most Lightning protection contractors .. Code References of any sort or jurisdiction are cool...



Welcome to the forum. I would recommend not taking on the job unless you are specifically trained and insured for the task.

Why is it in need of repair? Did it get cut?
 
Location
OBX, NC.
i'M JUST A JOURNEYMAN SERVICE TECH WHO IS BEING TOLD I MUST FIND THIS PARTICULAR COPPER CLAD WIRE THAT IS RELATIVELY THE SAME SIZE AS A #1 CU... fINDING THE WIRE WILL HOLD UP THE REPAIR AND PERSONALLY IN RECENT INSTALLATIONS OF COUNTER POISES I WAS ONLY SPEC' D TO INSTALL A SIZE SUITABLE FOR THE PRIMARY GROUNDING ELECTRODE... sO THE WIRE ACTUALLY USED FOR THE BURIED PART OF THE LIGHTNING PROTECTIONS COUNTER POISES i'M NOT FAMILAIR. ESPECIALLY CODES OR REGULATION. ik'D LIKE TO KNOW IF THE INDUSTRY USES COPPER CLAD FOR A REASON? I THOUGHT COPPER WOULD BE MORE EFFECTIVE?
 

mcclary's electrical

Senior Member
Location
VA
i'M JUST A JOURNEYMAN SERVICE TECH WHO IS BEING TOLD I MUST FIND THIS PARTICULAR COPPER CLAD WIRE THAT IS RELATIVELY THE SAME SIZE AS A #1 CU... fINDING THE WIRE WILL HOLD UP THE REPAIR AND PERSONALLY IN RECENT INSTALLATIONS OF COUNTER POISES I WAS ONLY SPEC' D TO INSTALL A SIZE SUITABLE FOR THE PRIMARY GROUNDING ELECTRODE... sO THE WIRE ACTUALLY USED FOR THE BURIED PART OF THE LIGHTNING PROTECTIONS COUNTER POISES i'M NOT FAMILAIR. ESPECIALLY CODES OR REGULATION. ik'D LIKE TO KNOW IF THE INDUSTRY USES COPPER CLAD FOR A REASON? I THOUGHT COPPER WOULD BE MORE EFFECTIVE?

I wish i could help you, but it's not my niche. I suspect the copper clad is purely for economical reasons. As long as you match circular mils, I think you're good. Buy again, I know nothing , I'm guessing
 
Location
OBX, NC.
you know as much as me.. My guess is also that the type copper /clad wire used regularly by lightning contractors is solely used over copper b/c of cost? Anyone who knows electrical theory can attest that copper should better support a surge than a combined copper. Maybe Idont really know what copper/clad is? Any input is appreciated... Im going to start googleing and all that jaz so if I come up with some concrete theory behind all this Ipost reply... Thanx all and good night.
 
You should determine the number of strands and gauge of the existing conductor before doing anything.

Structures under 75' are defined as Class I structures so the ground loop could be as small as a #2 or 29 strands, 17 gauge copper.

Structures over 75' are defined as Class II structures requiring between a 1/0 and 2/0 or 28 strands, 14 gauge copper.

BUT these are just the minimum required by the standards and the architect/engineer/owner may have required something completly different like a 4/0.

If there is enough slack you could use a mechanical splicer like a parallel or butt splicer or even an exothermic. Count the strands carefully and determine the gauge. Note: Conductor used for lightning protection should be labeled for lightning protection use by UL.
 

mcclary's electrical

Senior Member
Location
VA
You should determine the number of strands and gauge of the existing conductor before doing anything.

Structures under 75' are defined as Class I structures so the ground loop could be as small as a #2 or 29 strands, 17 gauge copper.

Structures over 75' are defined as Class II structures requiring between a 1/0 and 2/0 or 28 strands, 14 gauge copper.

BUT these are just the minimum required by the standards and the architect/engineer/owner may have required something completly different like a 4/0.

If there is enough slack you could use a mechanical splicer like a parallel or butt splicer or even an exothermic. Count the strands carefully and determine the gauge. Note: Conductor used for lightning protection should be labeled for lightning protection use by UL.



Thanks Man, Good info
 

dicklaxt

Senior Member
If I remember correctly the roof horizontals and downcomers must be a braided conductor made for Lightning Protection specifically,the downcomers must always be in a downward direction and not exceed 6 inch or 8 diameter radius bends(not sure which).The downcomer must be exothermic welded to a ground rod within 2 feet of the foundation and then bonded to a ground loop .I can't remember why a braided conductor but it is required and/or size was also limited.

This is all from memory but might be worth looking into.

dick
 
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Yes, main size conductor is either smooth weave or ropelay except some of the larger sizes are concentric strand. Cable bends should have a minumim radius of 8" and no less than 90 degrees. Connections to the ground rod and ground loop can be either exothermic or mechanical as long as the connection meets the UL standard for LPS.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
no more than 90 degrees would be less than 90 making a more closed corner

no less than 90 degrees would be more open corner

Here's a link to an outdated NFPA780 but it has an illustration of cable bends on page 28 of 108 that still applies.

http://www.atmo.arizona.edu/students/courselinks/spring07/atmo589/articles/NFPA_780_2004.pdf
I guess it depends on how you measure the 90. With conduit an bend of 95? would be a closed 90 not a open one. I guess the cable bends are measured on the inside and conduit bends are measured on the outside.
 
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