ECN Forum Forums Code Related Discussion NEC & other Code issues 05 equipotential bond.

Here is a question. I will be very interested to read the responses.

680.26 (A) and (B) establish the criteria for the equipotential bond.

If a fiberglass in ground pool were installed how would you view the application of 680.26 (C) (3). ??

For that matter how about the bonding grid under a pool deck without mesh.

The proposal only required such a grid for pools constructed of conductive materials. The 2005 wording appears to have broadened the application to apply to all pools.

Charlie Palmieri


[This message has been edited by cpal (edited 10-29-2004).]

cpal...I would interpet 680.26(C)(3) as follows,

When a "permanently installed" swimming pool is installed a equipotential bonding grid shall be established and it shall extend 3 feet horizontally from the water.

Connect this grid to the parts specified in 680.26(B)...which is basicly all other metalic parts and equipment associated with the pool.

Even with a fiberglass inground pool a grid must be installed.

So, I also would have to establish a bonding grid around a permanently installed pool which is above ground and surrounded with a grass lawn border.

Hopefully somebody comes out with an easier way to construct such a grid than 680.26(C)(3)b.

The purpose is to pick up any stray voltage that may be present.

Also, I'm not sure if the "mesh" commonly installed in a concrete deck pour is an acceptable method of establishing a grid...680.26(C)(1)describes reinforcing rods bonded together.?

shortcircuit

I agree . the question was submitted such a long time ago I forgot about it.

I would like to see more discussion regarding the 3' under the deck, and I would like to see an offical statement from the CMP regarding fiberglass pools.

The above ground pool was not considered but yes, this to may be a problem.

Charlie

We seldom see any steel in a pool deck these days, everyone uses fibermesh in the concrete. The new rule saying you don't have to bond epoxy encased rebar in the shell has left us with no real way to create that equipotential plane.
Should we try to propose a copper ring around the pool, buried in the concrete or just try to get some bare rebar?

If the pool does not have structural steel (metal) 680.26 (C) appears to require a manufactured grid. If the rebar is epoxyed 680.26 (B) (1) last sentence requries altenative means. Does (C) (3) provide the alternative means and does that means apply to fiberglass pools. And as mentioned what about above ground pools??

Charlie

If they are telling the installer they need a 12" x 12" #8 copper grid with a clamp at every intersection they are doubling the price of the shell. Essentually they are outlawing epoxy encased rebar.
Actualy I have never seen it in a pool but these are only half million to 1m houses ;-)

cpal...what does the last sentance of 680.26(C)(3)b mean...with tolerance of 100mm(4")

Also 680.26(C) says the bonding grid shall extend under "paved walking surfaces"...so it may not be required under other surfaces surronding a pool such as a grass lawn border typically seen around above ground permanently installed swimming pools.

shortcircuit

It means that you can use a 16" grid in place of the 12" one.
Don

It sure sounds like this #8 copper grid will even have to be under a brick paver pool deck, 3' from the water.
Steel mesh will just be orange sand in a few years so it would have to be copper.

Take note that the provisions of 680.26(C) apply to spas and hot tubs installed outdoors also

shortcircuit