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Posted By: sparkync Low voltage lights under 30 volts - 08/07/08 06:47 PM
Sorry to be putting so many post. I guess it's my day in the shop and going over the code. One thing I wished they would have changed is 411.4(B). As far as I'm concerned and obviously a few of the inspectors I've had dealings with, the ruling for lights under 30 volts, to have to be
10 ft. away from a pool, is ridiculas. You can put a 120 volt light under the water. and within 5 ft., but you can't put a low voltage light within 10 ft. of the pool. I realize that the low voltage light is not grounded, but neither is it grounded when it is in the front or back yard after a hard rain and is accessible to children, elderly, etc. etc. It refers to article 680, but there is nothing I can find about low voltage lights in 680. I've had more than one pool where it was pratically impossible to keep that distance. I've had at least 2 inspectors that agreed with me. Anybody else had this problem. Seems like it just creats confusion, at least on my part it does...
Sorry for the ranting... guess it's just my day... Steve..
Posted By: EV607797 Re: Low voltage lights under 30 volts - 08/07/08 11:35 PM
You aren't being ridiculous, Steve. I agree that this is downright silly. Then again, I think that lots of '08 changes are crazy. It screams of how much influence that the manufacturers have over the code. I'll bet that if any manufacturers of LV lighting had a seat on the NEC's board, this wouldn't be an issue at all.
Posted By: gfretwell Re: Low voltage lights under 30 volts - 08/08/08 05:49 AM
If you had the same grounding and bonding requirement on a Malibu light as you have for an underwater light I am sure it would be safe.
Posted By: harold endean Re: Low voltage lights under 30 volts - 11/09/08 05:24 PM
What does the manufacture instructions state? I have seen where the Manufactures instruction prohibits their lights within 10 feet of the pool. If that is the case, then they can't be there as per 110 of the NEC. Right? I am not saying that all manufactures do not allow their lights near the pool, just some of them.
Posted By: gfretwell Re: Low voltage lights under 30 volts - 11/09/08 11:23 PM
680 trumps 110.3(B). If it is not actually listed 680 safe I don't care what a manufacturer says on the label.
Posted By: sparky Re: Low voltage lights under 30 volts - 11/16/08 02:09 PM
perhaps a gfi's efficy on the line side of the low v x-former is a consideration here?
Posted By: gfretwell Re: Low voltage lights under 30 volts - 11/16/08 07:17 PM
A ground fault on the secondary of a LV lighting transformer will not trip a GFCI. In fact the "first fault" will not be seen at all. You will have just grounded what was an ungrounded source.
Posted By: sparky Re: Low voltage lights under 30 volts - 11/16/08 11:22 PM
ok gfretwell, so would this justify the spacing difference?

~S~
Posted By: gfretwell Re: Low voltage lights under 30 volts - 11/17/08 06:54 AM
Perhaps I didn't explain this clearly enough.
Low voltage lights are generally not GFCI protected, the primary protection will not protect for a fault on the secondary. If they did you could never keep those cheap Malibu lights burning. wink

I suppose if someone came out with a LV light that did have GFCI on the secondary side there would be a reason to reexamine this.
That will be nice idea if someone get the GFCI work on secondary side of LV luminaires but IMO you will get more GFCI trips than it should be.

But what I heard but not confirmed and myself I did see that some of the LV transfomer some of them have secondary side is on isolated format.

Merci,Marc
Posted By: gfretwell Re: Low voltage lights under 30 volts - 11/17/08 08:43 AM
If you used as much care wiring LV as you do in chapter 3 you shouldn't have as many trips. At 12v you need 10 times the fault conductivity to generate 5ma. (24,000 ohms @ 120v vs 2,400 @ 12v) I still doubt you could have those insulation piercing connections below grade that are common with the Malibu light but I doubt a few drops of water in a box would trip one.
Posted By: sparky Re: Low voltage lights under 30 volts - 11/18/08 01:05 AM
agreed gfretwell, i'm sure many among us can opine on the shakey installation of those plug & play landscape lights

~S~
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