ufer ground

[abe]

Hi
What is the proper clamp to connect #1/0 ground wire to ufer ground?
Also, what clamp to connect 1/0 to 1 inch water pipe?
Is there any picture or graphics to show the connection?
Do I need to sand the grooves on the rebar where the copper will sit on? and do I need to use any antioxidant on the connection?

 

[rcarroll]

If your connection is in concrete, then you need a clamp rated for concrete & 1/0. Sorry I can't get a picture up for you. Just out of curiosity, why are you using 1/0 to the ufer? #4 cu is the max required. You do not need to sand the rebar nor use anti oxident. Ron

 

[al hildenbrand]

From the UL White Book:

GROUNDING AND BONDING EQUIPMENT (KDER)

Ground Clamps ? Strap type ground clamps are not suitable for attachment of the grounding conductor of an interior wiring system to a grounding electrode.

Ground clamps and other connectors suitable for use where buried in earth or embedded in concrete are marked for such use. The marking may be abbreviated ??DB?? (for ??Direct Burial??).

Listed ground clamps are also suitable for telecommunication applications such as telephone, radio, CATV, and the like in accordance with Articles 800, 810, 820 and Section 250.94 of the NEC, in addition to those covered under Grounding and Bonding Equipment, Communication (KDSH).

Listed irreversible compression type connectors are suitable for splicing the grounding electrode conductor.

Clamps are intended for use with rod and/or pipe electrodes in accordance with the NEC and are marked with the size of electrode and electrode grounding conductor with which the clamp is intended to be used. Clamps suitable for use on copper water tubing are marked for such use.

 

[bphgravity]

Al missed one important part:

Clamps intended for use with re-bar are marked with the size of re-bar with which the clamp is intended to be used

 

[al hildenbrand]

Thanks Bryan.

You are absolutely correct.

 

[tom baker]

Abe, any clamp that is listed for concrete burial is suitable. Just follow the instructions. You don't need larger than a 4 AWG copper.

 

[monkey]

If your connection is in concrete, then you need a clamp rated for concrete & 1/0. Sorry I can't get a picture up for you. Just out of curiosity, why are you using 1/0 to the ufer? #4 cu is the max required. You do not need to sand the rebar nor use anti oxident. Ron

If I upgrade a dwelling from 200A to 400A and the original Ufer is not available, and the water service is plastic, then do the two driven rods become my main grounding electrodes, thus requiring 1/0 cu?

 

[George Stolz]

If I upgrade a dwelling from 200A to 400A and the original Ufer is not available, and the water service is plastic, then do the two driven rods become my main grounding electrodes, thus requiring 1/0 cu?

No, see 250.66(A). The GEC to a ground rod need only be a #6 CU, as long as there's not another electrode in line after the ground rod requiring a larger conductor (250.64(F)).

For instance if you were pulling one GEC to an electrode, and then moving directly to the next one, they would be sized thusly:

Water > Ufer > Ground Rod
..1/0.......4...............6

but if the rod were first in line, it would need to be a 1/0:

Ground Rod > Ufer > Water
......1/0...........1/0.......1/0