AG Pool wiring and other headaches

[prh129]

I would be interested in getting JohnT's take on this as he seems to have a lot of experience with this.

Although #8 is heavier than #12, I'm not convinced that it too would not be able to handle the current from a lightning hit. Lightning rods use #4 so I suspect that the pool bonding connections do not take lightning into consideration.

In an earlier post, JohnT talked about not grounding a circuit at more than one point. I understand the concept of current flowing through earth in this case but I don't know what the implications are.

I'm just trying to understand the concepts so since this thread started with a discussion about codes for wiring it seems appropriate to do so.

Peter

[matt4x4]

Well, this is a real grey area with the NEC, first off, when it comes to bonding and grounding, they are two different things, but are essentially the same thing.

Bonding means the connecting of metal object together. But in order to do proper bonding, the bonding has to tie to the Ground rod of the electrical system, otherwise the bonding is incomplete and essentailly does nothing other than making everything metal live when an electrical malfuntion occurs.

Grounding really just means connecting your electrical system's ground to an acceptable grounding location, that being the ground rod.

Now, I know John said not to ground to numerous points, this is where it gets really vague because the NEC states that you have to but are not limited to having ONE ground rod, one is the minimum, but it is acceptable to have secondary ground rods, they have to be tied together or be connected to common ground.
Since your pool rod and your house rod are in the same ground, and are connected to the same bonding wire (remeber that 12 guage back to the panel...) they are essentially tied together twice, once through the 12 guage, once through the ground/dirt. I believe the ground does not count since there is no sure way of telling whether or not the ground the pool sits on is connected to the ground the house sits on unless you have a geological study performed, and another factor is the distance between the two rods which could be so large that the resistance in the ground/dirt becomes big enough to make them two different grounds.

From what I can get out of the code (interpretation) you are doing NOTHING wrong by adding a ground rod to the pool, you are actually just ensuring a good solid working ground connection at that location exists, this really just comes into play for such acts as lightning, I'm not sure what I have for guage at the pool ground rod, but it's easily the thickness of a finger, looking at the other metal objects that are grounded around the outside of my house, it looked like #8 was the common denominator for what was used, then again, that's probably also the spool the electrician had for doing the inside bonding, so he just used it on the outside grounds as well.
I can tell you one thing, the house we have (custom built 3 yrs before we bought it) was extremely overbuilt, everything, and i mean everything, was absolutely perfect when we got it, there were a lot of "don't need it but nice to have it" things and the "wow, now that's a good idea" things, so it makes me think it was all done above and beyond the basic requirements.


It's all very confusing, it all ties to ground in the end,

[roxy]

May I add.....you shouldn't be in the pool during a lightning storm. Sorry couldn't help myself.

[matt4x4]

Roxy - I totally understand that, but when parents are out and teenagers are home, common sense sometimes goes out the window! Alsao, sometimes, it seems like a thunderstorm is a loooong ways away, you're in teh pool, starting to think it might be time to get out because of the approaching storm, when BANG, a rogue lightning hit. I understand it's probably a 1 in a billion chances, but hey, dung happens....

[roxy]

You are absolutely right...especially about the teens.......I remember , I was one once.