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Posted By: vars Cable TV Bonding question - 11/10/04 02:41 PM
Hello all,

I have a question about how to bond the cable TV grond to the electrical service ground.

This is a residence and electrical setup is as follows: 3/0 Cu SEC inside of 2" PVC to meter pan directly behind meter pan in garage is 200 AMP main breaker panel. Inside the main breaker panel is where the Grounded Conductor is bonded to the Grounding conductor. This panel contains only a 200 amp main breaker which feeds a sub panel in the basement about 10 feet away the feeder for this panel consists of Neutral 3/0 Cu, and two hot legs each 3/0 Cu and one #4 Cu EGC. In the subpanel the Neutral bus is isolated from the Ground bus.

My question is can I bond the Cable TV ground inside of the subpanel in the basement of the house? Or does this have to also be bonded where the Grounded electrode and Grounding electrode are bonded in the Main Breaker panel inside the garage? It would be convienent to be able to bond the cable tv system ground in the basement panel as there is plenty of room on the ground bus bar.

Sorry for the long post but I think I could use your help on this, reading 250.94 was not very clear on this.

thanks much!
Posted By: hbiss Re: Cable TV Bonding question - 11/10/04 04:47 PM
All ground bonds for telephone and CATV should be bonded to the service entrance. In your case this would be the disconnect in the garage. The services should have been brought to this same location with the electric anyway for this reason.

If you can't locate the ground block in the garage then run a ground from the basement to the garage. If you say this is only ten feet you will be well within the 20 foot limitation.

Keep in mind that you do not have to land the ground on the bus in the panel. You can simply bug onto the grounding electrode conductor outside of the panel. As a matter of fact this is preferred since it keeps "unauthorized" people away from inside the panel.

Posted By: sparky806 Re: Cable TV Bonding question - 11/10/04 07:06 PM
Look at 820.40(B)(1)
Posted By: LK Re: Cable TV Bonding question - 11/11/04 01:15 AM
We leave 4 to 6 inches on the GEC bare, just before the ground rod, this is where the Phone Company or Cable Co., will attach their ground.
Posted By: vars Re: Cable TV Bonding question - 11/11/04 02:38 AM
Ok so I have access to about 4-5" of bare GEC right before the first ground rod acorn clamp. And thanks to sparky806 after checking out 820.40 this is fair game to connect to, just like LK said.

So my new question is does anybody know of what kind of approved clamp/fastener I can use to bond the communications system ground to the 4" bare GEC?

Thanks for all the help!!
Posted By: hbiss Re: Cable TV Bonding question - 11/11/04 05:05 AM
Don't know why this is so difficult. Use any type of split bolt or vise type clamp cnnector that you would normally use to connect two wires to "bug" on to the wire.

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