0 members (),
21
guests, and
3
robots. |
Key:
Admin,
Global Mod,
Mod
|
|
|
Joined: Jan 2005
Posts: 354
Member
|
So why not allow low voltage lighting near a bathtub? If a new rule to allow this were like a combination of 680.33(A) and Article 411, could that possibly be safe? Maybe special luminaires designed for, and listed for, use near bathing water like that?
|
|
|
|
Joined: May 2005
Posts: 984 Likes: 1
Member
|
PLEASE understand that what kills folks is current...not voltage. The available current on a circuit is defined by the impedance of the system and the rated current of the power source; not by the working voltage or the little number stamped on the breaker. If the current available from the low-voltage transformer feeding the lights exceeds a rather small value, get ready to call the undertaker. It's possible to get a fatal current out of a transformer with a rated 12V output quite easily, especially since it only takes several milliamperes to result in a fatality by electrocution...and that doesn't even allow for the quite real possibility of someone being startled and cracking their skull while falling in the tub.
Ghost307
|
|
|
|
Joined: Mar 2001
Posts: 2,056
Member
|
Hey, ghost. Good point, but I think that 120 volts is much more likely (10 X) to push 100 milliamps through the resistance of the human body than 12 volts is. Being immersed in water obviously reduces body resistance greatly, and I wonder if it would be low enough to cause severe injury or worse. I once got hit by 24 VDC and it stung. I imagine if I was drenched, it would have been far worse.
|
|
|
|
Joined: Nov 2002
Posts: 794 Likes: 3
Member
|
For the 12V bulbs, if you use a transformer that is centertapped with tap to ground, such that you only have 6V from ground, that might cut the shock hazard enough in such a wet environment (someone standing in ankle deep water trying to change a bulb).
Or some manufacturer will need to develop a fiber optic method such that the bulb itself is far away from the tub, and the pendants are all non-conductive except for grounded metal parts...
|
|
|
|
Joined: Jan 2003
Posts: 4,391
Moderator
|
I have been looking at 410 and 411 and I am not certain that the NEC prohibits low volt fixtures in the bathtub zone. Yes for certain 410.4(D) says: No parts of cord-connected luminaires (fixtures), hanging luminaires (fixtures), lighting track, pendants, or ceiling-suspended (paddle) fans shall be located within..... But now look at 410.2 410.2 Application of Other Articles.
Equipment for use in hazardous (classified) locations shall conform to Articles 500 through 517. Lighting systems operating at 30 volts or less shall conform to Article 411..... Than 411.1 411.1 Scope. This article covers lighting systems operating at 30 volts or less and their associated components. and finally 411.4 411.4 Locations Not Permitted. Lighting systems operating at 30 volts or less shall not be installed (1) where concealed or extended through a building wall, unless using a wiring method specified in Chapter 3, or (2) within 3.0 m (10 ft) of pools, spas, fountains, or similar locations, except as permitted by Article 680. I don't see tubs in that list. I do not think 410.4(D) applies to low voltage lighting systems. What do you all think? Bob
Bob Badger Construction & Maintenance Electrician Massachusetts
|
|
|
|
Joined: Jun 2003
Posts: 681
Member
|
Bob Take a look at 411.4(B), that may preclude the use of 30v or less around tubs.
Pierre Belarge
|
|
|
|
Joined: Apr 2006
Posts: 3
Junior Member
|
Note that the use of low voltage lighting with a transformer defeats the GFCI function. A GFCI only sees current escaping to ground on the primary, not the secondary. Remember, the GFCI does not sense current on the ground lead, only a mismatch on the line and neutral leads.
|
|
|
|
Joined: Jun 2002
Posts: 58
Member
|
I would think that there is fiber-optic or LED lighting available that may be suitable. I certainly wouldn't approve installing a shock or shatter hazard, Darwin-Award-nominations not withstanding!!! energy7
|
|
|
|
Joined: May 2005
Posts: 984 Likes: 1
Member
|
I'm sure that somebody makes a fiber-optic unit to do this in a residence. I know that there are commercial units. It'd be a LOT cheaper than the lawsuit when some idiot gets hurt (or worse).
Ghost307
|
|
|
|
Joined: Apr 2002
Posts: 7,382 Likes: 7
Member
|
On the subject, but not related to your pic. Custom home, huge master bath, 22' cupola type thing with windows, owner/builder & decorator want a chandelier installed. Bottom of fixture will be 16' above high water. I said "NO".
Decorator came up with having the 'bottom' of the cupola thing enclosed with plexiglass, which will technically 'enclose' the fixture. Relamp would be accomplished thru one of the windows, I guess.
Any comments gentlemen??????
John
John
|
|
|
Posts: 46
Joined: March 2013
|
|
|
|