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I'm planing to do my own electrical wiring for a new house, and the cable company needs something to attach their ground wire to when they mount the demarcation box.

I'd like a clean looking install, so I was thinking that I would just have a piece of 1" RNC coming out of the bottom of the outside panel (the one with the meter) that protects the #4 copper wire on the way down to the ground rods. The conduit would end at the grade level and the #4 would come out of it there.

But this doesn't give the telco anything to bond to on the wall. Is there a nice looking way to get a code compliant ground hookup next to where the demarcation box goes for them? Some type of nice looking box conencted to the panel via conduit so there's not just a sloppy looking wire draped across the side of the house like I see on some houses?

Update:

I found this gadget from Arlington: http://www.aifittings.com/catalog/grounding/intersystem-grounding-bridges-with-pvc-adapter/GBB5P which might do the trick. It's meant for 1/2" RNC. I'm interested to know if the conduit that the ground wire is in can turn after it comes out of the electrical box, go horizontal across the wall a few feet to where the dmarc is, then have one of these gadgets installed on it's way down to the ground? Is there any code reason why that wouldn't be permitted?

I'm also interested to know if the code would allow the a ground wire from the panel to go through the wall and into the dmarc through the conduit that the coax enters the building through, as one answer suggested. This would be very clean, but I'm not sure if it meets the NEC requirements in 250.94.

Nick
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2 Answers2

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Do a search for "Intersystem Bonding". You should be able to find quite a few devices on the market, hopefully one of them suits your fancy.

Basically, you'll install an intersystem bonding termination device (with at least 3 terminals) near the electrical service entrance. Then you'll bond the IBT back to the grounding electrode system, using a 6 AWG copper conductor. You should be able to find an IBT device that can mount directly to the meter base or service panel enclosure, if that's more convenient for you.

Intersystem Bonding Termination 250.94

Here's an article from the International Association of Electrical Inspectors (IAEI) magazine, that discusses the NEC 250.94 rules.

Tester101
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Route the ground wire for the demarc inside the wall cavity, not outside the structure. The ground wire can connect to the ground bus bar inside your breaker box or bonded to the #4 grounding wire inside your electrical service entrance.

It can come out out of the wall directly behind the demarc box and probably even use the same hole as the the communication cable.

Dotes
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