I am installing 2 wet niche pool lights (120V). There is a circuit panel in the pool shed and the lamps are on their own gfci breaker. However, next to the circuit panel is a pool controller/computer with its own equipment ground. The lights are wired from the circuit panel into the computer box. I then ran 1 #8 insulated wire from the equipment ground of the computer box to the equipment ground on the breaker panel. Since the wiring for the pool lights is in nonmetallic conduit (PVC), I have also run an insulated #8 ground wire from the forming shell of each light. Where would I terminate the ground wire. Can it be terminated in the computer controller box on the equipment ground, or should it be run back to the breaker box and terminate on the equipment ground there?
After reading article 680-25(b)(4) and (4)(a) I get the impression that you could connect the wet-niche lights' EGC to the EGC in the pool controller/computer. Are there any instructions, etc., shown on the pool controller/computer? Is there a grounding terminal in the pool controller/computer for the lights' EGC?
[This message has been edited by Mike (edited 06-01-2001).]
Re: grounding wet niche pool light#77422 06/01/0103:43 PM06/01/0103:43 PM
No, there were no instructions for the light installation. What I did was run the hot, neutral and ground that were in the light cord to the controller. Then I ran the #8 ga EGC from the wet niche directly to the equipment ground in the breaker panel. I guess this seems more conservative than need be.
Re: grounding wet niche pool light#77423 06/02/0110:43 PM06/02/0110:43 PM
Dave, hopefully you got my reply on Do-It-Yourself. Basically what it says is that the conduit feeding the wet nitch forming shell needs to be connected to an approved j-box, which will have the necessary lugs to terminate the insulated #8 run in the conduit to the light. This is a code requirement.
The light's egc, which is in the cord, will also land in the j-box, on it's own terminal.
From there you run a egc (insulated) from the controller to the j-box, and land it on it's own terminal.
Hopefully this has helped.
Re: grounding wet niche pool light#77424 06/04/0102:26 PM06/04/0102:26 PM
I guess I'm still confused. I thought that the #12 ground conductor that came with the light went straight back to the equipment ground. The insulated #8 from the bonding lug inside the wet niche is terminated on a screw in the jbox. I must also terminate the #12 in the j box on another lug, then from there goes back to the ground bar in the circuit panel? How about the #8 insulated ground. Does it just terminate in the j box or does that then proceed back to the circuit panel. Thanks. Sorry about my confusion.
Re: grounding wet niche pool light#77425 06/11/0110:59 PM06/11/0110:59 PM
Dave,hope I'm in time to help. When using non-metallic conduit to the light niche forming shell, you must run a #8 insulated conductor(stranded pulls easier)to the forming shell and connect it to the ground connector within the shell. This connection must then be potted in an approved potting compound (3M or Aquabond are the 2 most common, Aquabond being a repackaged 3M product). This is all in addition to the prewired light fixture cord that comes with your pool light(do not disassemble the cord within the fixture.The other most common way of installing conduit is to run brass conduit to the forming shell, usually a metal forming shell, thereby eliminating the need for an additional ground wire. In either case the conduit must connect to a junction box or enclosure listed for making the light niche connection(s). Most pool subpanels are NOT listed for direct connection to the light niche conduit, so the conduit is run to a special junction box with integral terminals. Although not required, most contractors will seal the conduit from the light niches at this point to prevent pool water condensation or gases from entering j-box and causing corrosion, silicone is usually used. Enclosure(s) must be listed if to be used instead of the j-boxes, and Article 680 describes the requirements, including seal-off(s) to prevent pool water gases from entering the enclosure. The #8 is required only within the run from j-box to forming shell, so often the typical size conductor used is either #12 or #14 from j-box to pool subpanel, depending on your lighting load. When wiring the GFCI, be sure to isolate the GFCI unit so that GFCI-protected conductors are not sharing conduit, enclosures, or raceways with non-GFCI protected conductors. Finally, always use a GFCI tester to make sure that the GFCI is tripping properly, DO NOT DEPEND ON JUST PUSHING THE TEST BUTTON ON THE GFCI UNIT, TOO MANY TIMES I HAVE FOUND POOL CONTRACTORS REVERSE WIRING THE GFCI UNITS(TO LOAD INSTEAD OF LINE), THUS RENDERING THE GFCI UNIT USELESS. If you have any additional questions feel free to email me @ SPEX2000@aol.com
[This message has been edited by Spex2000 (edited 06-18-2001).]
Re: grounding wet niche pool light#77426 06/12/0108:51 AM06/12/0108:51 AM
To answer your questions: Yes, Aquabond is listed as a potting compound. As I said, it is manufactured by 3M and licensed to Aquabond for repackaging. Its really a great system for those using it on a regular basis. All we ask is that they leave the disposable application tube after use. The material is fairly hard after it sets up, so its easy to tell that they are not using silicone or Henrys roof tar.
As far as the red brass conduit- good question, I would imagine that the pool material supplier stocks it along with the metal forming shells and pool light jboxes, and Aquabond and 3M potting compound, all things that you will not find at a typical electrical supply house, I doubt that they would want to compete with the pool suppliers.