Low Voltage Grounding / Bonding question

[cowboyjosh]

So in a new house im building im having a little arguement with the EC. The EC ran a #10 wire from the low volt can to the main electric panel. He wants to tie the low voltage bond to the ground in the electric panel. Mean while the Ufer is only 5 feet from the main panel and is accessable. I want the low volt bonded directly to the Ufer. What do yall think? The low volt contractor could give a rats *** so long as his **** gets grounded / bonded.

 

[fefarms]

So in a new house im building im having a little arguement with the EC. The EC ran a #10 wire from the low volt can to the main electric panel. He wants to tie the low voltage bond to the ground in the electric panel. Mean while the Ufer is only 5 feet from the main panel and is accessable. I want the low volt bonded directly to the Ufer. What do yall think? The low volt contractor could give a rats *** so long as his **** gets grounded / bonded.

My vote is to bond everything at the service entrance. This minimizes the possibility of ground loops.

Bonding to the UFER ground seems like a less-optimal idea. The utility will probably provide a lower resistance path to earth ground (through the service entrance cables) than your UFER.

Either arrangement is most likely code-legal, although the bond at the panel is the more common.

 

[mrb]

uh, thats not ok. the GEC for the intersystem bonding has to be min #6 and make sure its terminated in one of the acceptable fashions. There is some good info here http://www.erico.com/public/library/fep/LT19313.pdf and pg2 has the NEC requirements.

 

[cowboyjosh]

Theres a Square D meter / feed thru panel on the side of the house and the 2 40 space panels are in the basement. The EC wants to tie the low volt Equipment in the basement, into either of the 2 basement panels. On the outside per code below the feed thru is the inter system bonding termination connected with the required number 6 where the Qwest d mark box, Comcast, and lightning rods bond too, i guess the EC is right going into the electric panel for the low volt equipment in the basement keeping everything "common".

 

[mrb]

ah ok, i thought you were talking about the GECs to the phone and cable demarcs. whats the ground in the LV panel for? things like a satellite multiswitch, etc? I would run that to the intersystem terminal. Seems odd what he's doing.

 

[cowboyjosh]

Yeah, he has to ground / bond the Leviton low volt cans, also the security system, cctv, and pbx the homeowner is installing required a ground / bond connection, mostly for lightning protection. The arguement is should the above be brought to the ground on the electric panels or right to the Ufer, since both options should keep the low volt cans and **** common.

On all the consumer equipment above there are terminals for additional grounding / bonding as the equipment ground isnt good enough for lightning protection.

Thanks for your help.

 

[mrb]

Yeah, he has to ground / bond the Leviton low volt cans, also the security system, cctv, and pbx the homeowner is installing required a ground / bond connection, mostly for lightning protection. The arguement is should the above be brought to the ground on the electric panels or right to the Ufer, since both options should keep the low volt cans and **** common.

especially for lightning protection it should go right to the intersystem bond, with something lower impedance than #10.

 

[cowboyjosh]

Best we can do at this point is to run a 6 to the basement panel or ufer, walls closed up and painted leading to the outside to the isbt. Looking for lowest resistence, i dont know if thats thru the panel or ufer.

Thanks again for you help...

 

[mrb]

if it were me id go to the UFER directly. much less impedance then through the panel.

 

[cowboyjosh]

if it were me id go to the UFER directly. much less impedance then through the panel.

Great its settled then. My arguement to the ec was that the ufer is where the motor for the jetted tub, and the feed thru panel too ultimately connect to and its the path of resistence. To my surprise the ahj doesnt care about low volt bonding. Actually my arguement isnt so much as to with the ec as it is to the Super in charge of my project, hes one of those fellas that tries to over talk the builder (me) and homeowners, hes not a good people person.