rebel34

I want to make sure I understand Equipotential and pool bonding, say we put in a fiberglass inground pool, a copper wire is run aound the pool, the you run a #8 bare from the light niche to this ring, same way with pool ladder and drain cover, then from that ring to the bonding lug on the pool filter pump motor, am I correct so far? I also understand that you dont necessarily have to run the bonding wire back to the panel is this correct?

Speedy Petey

First off you do NOT have to run a ring around the pool (although it does usually wind up this way). This is a myth, yet I see many guys do it. Mostly pool guys I must say.

You simply have to hit every metallic item located within a certain distance of the pool, and anything electric related to the pool.
You can go from the pool coping, to the niche, to the ladder cups (both), to the railing cups, to the motor, to the heater, IF this is all there is. Most of these items have a lug to lay the wire into without splicing. If not you just attach a lay-in lug and connect to it.

Don't forget, 2008 added a requirement for a dedicated grid under walk areas. I am not up on that quite yet but others can give details if they know.

What code cycle are you under?

rebel34

we are currently under 2005, and what about taking the bonding wire to the main panel?

Speedy Petey

NOT at all necessary.

Here is the NEC Handbook commentary on that question:

It is important to understand the difference between the terms bonding and grounding as they apply to Article 680. As defined in Article 100, bonding is ``the permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed.'' As described in 680.26(A), the function of equipotential bonding differs from the function of bonding to meet the requirements of Article 250 in that providing a path for ground fault current is not the function of the equipotential bonding grid and associated bonding conductors.
Creating an electrically safe environment in and around permanently installed swimming pools requires the installation of a bonding system with the sole function of establishing equal electrical potential (voltage) in the vicinity of the swimming pool. A person who is immersed in a pool or who is dripping wet, has a large amount of exposed skin, and is lying or walking on a concrete deck is extremely susceptible to any differences in electrical potential that may be present in the pool area.
The primary purpose of bonding in and around swimming pools is to ensure that voltage gradients in the pool area are not present. The fine print note explains that the 8 AWG conductor's only function is equipotential bonding to eliminate the voltage gradient in the pool area.
The reason for connecting metal parts (ladders, handrails, water-circulating equipment, forming shells, diving boards, etc.) to a common bonding grid [pool reinforcing steel, pool metal wall, or an alternative bonding grid as described in 680.26(C)(3)] is to ensure that all such metal parts are at the same electrical potential. The grid reduces possible injurious or disabling shock hazards created by stray currents in the ground or piping connected to the swimming pool. Stray currents can also exist in nonmetallic piping because of the low resistivity of chlorinated water.

rebel34

Thanks for the help, I understand it better now, the guys i know that put these pools in say 1. they have been bonding all parts of the pool then putting in a ground rod to hook these to 2. Running a green #8 to the pump motors from the panel, I told them they were doing it wrong, but they said they had always done it that way, The last one (first for me )was done my way which I learned a lot about on this forum about the bonding. BTW they had to use me because it was a new commercial pool and had to have a electrician because they had to have a permit.

Speedy Petey

Don't you just love the old "We've always done it that way" mentality?
I DON'T!

sparky73

Yeah I love that. The guys doing the pool I'm working on said the same thing. I've been doing it like this since the 60's I told him, well bub times change and so does the code.

macmikeman

Petey, I don't have my code book handy right now, but does it really require that you continue one bonding wire without any splice? Not to my recall. I think the picture in the 2005 handbook clearly shows multiple taps off the rebar to the various metal objects needing to be on that grid. 680.10?

heel600

As long as everything is tied together with the #8, you're fine.

On a vinyl pool, I just put a lug on the steel frame, and go to the cups (or diving board, or the grid for under the walk)

On a concrete pool, I just tap everything off of the rebar.

I run one wire from the pool to the pump area, and then I split off from there (using DB split bolts) to go to the pump, heater, Chlorine Generator, Jande control, etc.

For the pool lights, I do the #8 in the PVC from niche to deck box. I also run a #8 from the pool (steel frame or rebar) to the outside lug on the niche, then to the deck box (in one piece). Code does NOT require the wire between the niche and deck box on the outside, but hey, 120V in water, I feel the $4 of wire is worth it.

Lastly, I saw on some thread that deck boxes need to be supported by a piece or rigid (or other support). I NEVER supported a deck box with anything but the 2 or 3 1" PVC pipes. The box is only 6-8 inches above grade, and NOT in a walk way. Yes it IS allowed (314.23(e)). Unless the rigid is set in substantial concete, the rigid isn't really doing anything.

The above is all based on NEC 2005. We don't change until August.

Speedy Petey

No it doesn't. That was not what I meant if you read it that way. I was just trying to describe everything that needed to be hit with the bonding grid wire.

Speedy Petey

Heel,

If you are referring to the other thread on this board, the poster asked if he could use a piece of gal rigid to support the box better. I merely said that if he did it would have to be brass. That or use a piece of gal as a separate support.
I never said it was required.

sirswift93

After you connect the #8 from the Light Niche to the J-Box do you connect the ground from the light to the J-Box and then ground the J-Box to the pool Sub-Panel?

heel600

By J-box I assume you mean the deck box. Yes, yes, and yes. Just remember the ground must be 12 ga to the panel

sirswift93

Do I ground the Deck Box to the Sub-Panel bus-bar or just bond it to metal box? I thought the whole idea of bonding was not to earth ground or bus-bar ground.

Thanks

Stickboy1375

Here are some basic pics of bonding a pool.

680.26(B)(1).jpg


680.26(B)(6).jpg



Ignore the transformer if it does not apply.
680.23(F).jpg

sirswift93

Thanks Stickboy. However, what about the ground wire from the J-Box? I have a #8 wire bonded to the brass conduit running from the light niche to the brass J-box. Then the ground wire from this light is connected to the grounding post of the J-box (correct?). Then the ground wire from the pool sub panel bus-bar is connected to another grounding post on the J-box (correct?).

Stickboy1375

Your confusing grounding and bonding, not that what your doing it wrong, but your not sure if your doing it right either. You need to be confident in your work and understand everything your doing, you really need to study up more on article 680. here is a PDF file to help you along.

http://www.mikeholt.com/files/PDF/Pooldownload.pdf

Stickboy1375

If your asking if the pool light j-box needs to be bonded, the answer is no, unless of course it was within 5' of the pool, but they need to be 4' minimum away anyways, so its usually not an issue.

sirswift93

My jbox was under my diving board and is 5ft away from the inside of the pool. But, doesn't the lights ground wire have to be grounded back to the pool panel's bus-bar?

Also, even though my pump and heater are more than 5ft away from the pool (more like 20ft) do I steel need to bond them?

Speedy Petey

sirswift, is this for a customer? Are you the electrician?