ECN Forum
Posted By: Micmann Pool light GFI - 06/14/05 12:17 AM
I’m wiring a small above ground pool for a customer. The pool has a light that gets mounted in the side of the vinyl wall by the pool company and I’m supposed to wire it. The light unit is self contained, in that it is a sealed transformer box with a 3’ cord for power coming out and 10’ of cord for the 12v side going to the light in the side of the pool. The sealed unit has a built in GFCI and reset button. I’m running one 12/2 UF cable from the house to outside and then sleeve the UF in PVC to a 4x6 post. I’m GFI’ing the line at the panel. My question is that since this transformer unit has it’s own GFI and I will be installing it on a GFI’d line Does anyone see a potential problem. Any problem of GFI’ing a GFI? I do not want to run two circuits since I have to do some snaking through the basement. Any thoughts?

Jeff
Posted By: gfretwell Re: Pool light GFI - 06/14/05 12:59 AM
You may have an AHJ that wants an insulated #12 ground wire. I would ask before I strung in the UF.

The GFI on a GFI is not a problem. That is very common with outside equipment that has internal protection.
Posted By: gfretwell Re: Pool light GFI - 06/14/05 01:28 AM
I looked at 680 and I am not sure how an above ground pool light gets relief from any of the 680.23 and 680.24 rules. We don't see much "above ground" here and I have never wired one of those lights. You should probably take a peek and see what makes sense with what they gave you.
I think you are going to be "equipotential" bonding with some #8, laying conduit to the house and buying a listed junction box. Also note that your insulated #12cu EGC shall be unspliced to the J box.

If this thing has a cord cap on it they must be in another article in the code I don't know about.
Posted By: Micmann Re: Pool light GFI - 06/14/05 02:45 PM
The unit does come with a cord cap. It looks like a kit from Wal-Mart. The instructions for a temporary pool say to just plug it in (of course the homeowner would probably run a nice extension cord through a basement window or something, non GFI’d). Anyway, this is a permanent pool and the instructions say to (believe it or not) mount the unit to one of the stanchions on the pool (120v right on the pool, nice). To do this they give you an adaptor that slides on the bottom of the trans. unit with a ½” treaded KO. They tell you to conduit into the KO and cut the cord cap off and make a splice in the adaptor. I’m not mounting the unit to the pool. I’m mounting the trans. unit to the 4x6 post and K-flexing into the adapting piece, cutting the cord cap and making my splices inside the adaptor. Then cutting the spade connectors on the low volt cord and sleeving it through PVC to the pool light and re-crimping the spade connectors. The fixture that mounts to the pool is all plastic with no place to bond which according to 680.26(b)(2) is ok. It all comes pre-made so I’m trying to make it code compliant.

As to the UF. I’ll ask the AHJ. But according to 680.21(A)(4) I’m seeing the UF, as far as the code is concerned, as OK. Am I correct?

Jeff
Posted By: caselec Re: Pool light GFI - 06/14/05 03:07 PM
Jeff, for the pool motor you could use type UF inside the dwelling but as soon as you are outside you will need to use one of the wiring methods approved by 680.21(A)(1).

680.21 Motors
(A) Wiring Methods
(1) General The branch circuits for pool-associated motors shall be installed in rigid metal conduit, intermediate metal conduit, rigid nonmetallic conduit, or Type MC cable listed for the location. Other wiring methods and materials shall be permitted in specific locations or applications as covered in this section. Any wiring method employed shall contain an insulated copper equipment grounding conductor sized in accordance with 250.122 but not smaller than 12 AWG.

(4) One-Family Dwellings In the interior of one-family dwellings, or in the interior of accessory buildings associated with a one-family dwelling, any of the wiring methods recognized in Chapter 3 of this Code that comply with the provisions of this paragraph shall be permitted. Where run in a cable assembly, the equipment grounding conductor shall be permitted to be uninsulated, but it shall be enclosed within the outer sheath of the cable assembly.



I don’t know anything about the type of light you are using but if you review 680.23 you will see that UF cable is not approved to supply any of the lighting in that section.

(F) Branch-Circuit Wiring
(1) Wiring Methods Branch-circuit wiring on the supply side of enclosures and junction boxes connected to conduits run to wet-niche and no-niche luminaires (fixtures), and the field wiring compartments of dry-niche luminaires (fixtures), shall be installed using rigid metal conduit, intermediate metal conduit, liquidtight flexible nonmetallic conduit, or rigid nonmetallic conduit. Where installed on buildings, electrical metallic tubing shall be permitted, and where installed within buildings, electrical nonmetallic tubing, Type MC cable, or electrical metallic tubing shall be permitted.

Exception: Where connecting to transformers for pool lights, liquidtight flexible metal conduit or liquidtight flexible nonmetallic conduit shall be permitted. The length shall not exceed 1.8 m (6 ft) for any one length or exceed 3.0 m (10 ft) in total length used. Liquidtight flexible nonmetallic conduit, Type B (LFNC-B), shall be permitted in lengths longer than 1.8 m (6 ft).

(2) Equipment Grounding Through-wall lighting assemblies, wet-niche, dry-niche, or no-niche luminaires (lighting fixtures) shall be connected to an insulated copper equipment grounding conductor installed with the circuit conductors. The equipment grounding conductor shall be installed without joint or splice except as permitted in (F)(2)(a) and (F)(2)(b). The equipment grounding conductor shall be sized in accordance with Table 250.122 but shall not be smaller than 12 AWG.



Curt
Posted By: gfretwell Re: Pool light GFI - 06/14/05 04:18 PM
You really have to talk to the AHJ and do it before you alter the light. They may be taking it back.
This sounds like something sold for a "storable pool" and not suitable for a permanent pool.
Posted By: Micmann Re: Pool light GFI - 06/14/05 04:32 PM
Curt:

Thanks for the clarification I’ll change to individual conductors upon exiting the house.

But now let me back up because you have me wondering and I need some clarification.
Because of 680.23(F)(1) are you saying that because of the light I need to conduit all the way back to the panel?

(F) Branch-Circuit Wiring
(1) Wiring Methods Branch-circuit wiring on the supply side of enclosures and junction boxes connected to conduits run to wet-niche and no-niche luminaires (fixtures), and the field wiring compartments of dry-niche luminaires (fixtures), shall be installed using rigid metal conduit, intermediate metal conduit, liquidtight flexible nonmetallic conduit, or rigid nonmetallic conduit. Where installed on buildings, electrical metallic tubing shall be permitted, and where installed within buildings, electrical nonmetallic tubing, Type MC cable, or electrical metallic tubing shall be permitted.

I see this as needing to conduit (flexible or rigid) from the transformer unit to the shutoff switch box and then this code section would stop there because the transformer unit would be the only part connected to a conduit run to the light fixture. Anything before the trans. unit goes back to 680.21 Or am I wrong?

Also, I’m now wondering about the sleeving of the low volt side cord. The PVC is only to sleeve. There is no provision to enter the PVC into the trans. unit or the light fixture. In other words the PVC will be open on both ends with the cord going in and coming out. I really hate the pre-made cheep stuff that we get handed by homeowners and manufacturer’s. Maybe I’m making this difficult, but I see no other way of installing this thing.

Jeff
Posted By: Micmann Re: Pool light GFI - 06/14/05 04:37 PM
Gfretwell:

I’m definitely putting a call into the AHJ. The funny thing is the instructions for the unit has two sections. One for storable pools and one for permanent pools. The section for permanent pools tells you to alter it. I really hate this stuff.

Jeff
Posted By: LK Re: Pool light GFI - 03/28/06 06:59 AM
We see these cheap LV lights all the time, what i would like to know is a seperate conduit run required, and an unspliced ground, for these 12V transformer lights.
Posted By: renosteinke Re: Pool light GFI - 03/28/06 03:18 PM
Is the thing UL listed? If it were, that would be some assurance these isues were at least considered, and the instructions reviewed.
Posted By: earlydean Re: Pool light GFI - 03/28/06 10:42 PM
Simplified rules of 680.21 for motors:
Commercial Pools- insulated minimum #12 copper equipment ground all the way to the panel.
One Family Pools- insulated minimum #12 copper equipment ground only to the house, then #12 covered ground inside the house OK.

680.23(F) adds for underwater luminaires:
Both Commercial and One Family- insulated minimum #12 copper equipment grounding conductor without splice all the way to the panel, except splices are allowed for the deck box, time clocks, switches, GFCIs and transformers.
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