While looking at Article 680.42 I have come to the realization that there is no exemption from a perimeter surface grid for spas and hot tubs. 2008 NEC. I have not been asking for this as part of the bonding. What am I missing?
Thanks Greg, I was expecting to see an exception for a spa or hot tub on a wooden deck. If the concern is the voltage gradients in the earth and the deck separates the spa from the earth- what's the hazard? Maybe the wood when wet could be an issue???
The other thing that don't make sense is the fact that we don't need a perimeter surface grid for a storable pool and it typically is setting right on the ground allowing a person to be outside the pool standing on the ground and have their hands in the pool water???
George, I see where you are going. If this is a non conductive decking surface, I agree I am not sure how you bond it. I usually hear about the issue being a packaged spa dropped on a concrete or other type of paved deck. I understood expanding this to the grass but I think they missed something. Does the 2011 address non conductive decking? I know that was the usual mitigation, adding a 3' deck around the spa.
Reno I would not be "shocked" if we did see something about bonding the water in homes with electric water heaters and plastic pipe. Most new water heaters do come with steel stub ups that would give you at least 9 sq/on of surface and it is bonded to the EGC but I doubt that would trip a 30a breaker. I know that copper piping will, because my neighbor had an element open up to the water and it was like a bolted fault. You could hear water boil for about a second and the breaker tripped.
WHat's next? Equi-grids for the kitchen disposal, dishwasher, and whirlpool tub in the bath? Heck, let's do the whole yard, in case someone later installs a birdbath.
Heaven forbid someone decide to shift the package unit over to the other side of the patio, or set it up in the garage in the winter. After all, they get filled with a garden hose, and can go anywhere.
I'll tell you where this will all lead. It will lead to a world where Billy-bob 'hillbilly engineers' some bit of kludge that is truly dangerous, everyone makes an occupation out of avoiding city hall at all costs, and every street will have some bitter harridan peering through fence slats hoping to cause trouble for the neighbors.
In about three or four code cycles it will be against the code to put electricity in a house at all!!! Everytime somebody invents a new widget, a new code chapter gets written to require its use, needed or not. Arc Fault, Ground Fault, Tamper Resistant, and in use devices have more than doubled the cost of wiring a house with no end in sight. The end result will be some really dangerous stuff thrown together to avoid calling an electrician at any cost.
Life is tough, Life is tougher when you are stupid
Look who sits on the code making panels, what do you think there job is? Granted now some of the new products are great and they are real time savers. However just because someone invents something new, shouldn't mean that the code has to be changed and that the new product is required to be installed. Just my opinion.