Pool Bonding

[Greg Fretwell]

680.26(C)(3)(a) says "The grid shall be constructed of minimum #8 AWG bare solid copper conductors ... bonded to each other at all points of crossing ... <per 680(D)> ... in accordance with 250.8" (exothermic welding, listed pressure connectors, listed clamps, or other listed means).
The ground mats are listed.

[Greg Fretwell]

This is new in 2005

[Paul W. Abernathy]

Yep.....I was trying to get some info before I got back in the office to the 2005 NEC..but you answered it...thanks......talk about cost with the price of copper going up.......

[Harvey Gordon]

Paul and Jeff...I believe then that I was mis-educated....unless this grid is recent...I was told that all was to be bonded back to the pool pump...now is that simply a work around?

[Paul W. Abernathy]

Harvy,

The requirement for the bonding grid is not new, what greg is refering to has to do with an new addition to the 2005 NEC. The bonding of the grid to as listed in the previous responses are the same as they have been. With exception to a newly added verbage in 2002....

Hope that helps..

[Greg Fretwell]

Harvey, they should be going to the pump in this grid. They may have just bought a new pump and didn't hook up the wire but it should be there. If not they have to run a wire to the grid. It may be able to be picked up at the underground light J box if they have a light.

[Pierre Belarge]

The grid that is required based on the '05 NEC is going to be a deal breaker for some pools, and I believe will create people finding a way around it. It will be an expensive addition to the pool itself, and pool sellers are not telling their clients about the requirement, until after the pool is almost installed.

Harvey
The bonding of pools is not quite the same as bonding of systems. The purpose of bonding at pools is to create an " Equipotential Bonding Grid".
This grid will keep all points at the same Potential. In other words, if there is an elevation in voltage in the pool area (lets say lightning hits around a mile away and it is traveling through the earth), the voltage elevation will be the same in all of the protected areas, so there is no potential... no potential means not current flow... even though there is a higher voltage in the area, because there is no current flow, all people are protected and safe from shock. That is the theory behind this.

One of the good things is this "Equipotential grid" is not required to be installed as one piece of conductor. It is bonding (which is another word for connection), so it can be installed in pieces.

Yes, one will need to bond to the pump motor, even if the pump motor and equipment may be 100 feet from the pool, as some pool equipment is installed at some distance from the pool for various reasons. If the bond conductor is installed at a remote location for the pump, the burial depth for the bond conductor is not stated in the NEC.

[Greg Fretwell]

This grid has to be #8 copper. It is a 2005 requirement.