The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Correct rotation, wrong sequence
by Potseal
Yesterday at 03:14 PM
Industrail Control Panel bonding per 409.108
by sparkyinak
12/09/16 06:29 PM
Calling all Non-US members!! (Non-US only)
by aussie240
12/07/16 02:39 AM
Photo Upload Tutorial
by DanK
12/06/16 11:35 PM
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 11
HotLine1 10
Potseal 9
sparkyinak 8
Texas_Ranger 7
Who's Online
1 registered (geoff in UK), 205 Guests and 5 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#201778 - 06/23/11 01:07 PM Heated Shower Mirror
ptfw30 Offline
New Member

Registered: 06/23/11
Posts: 3
Loc: NY
Hello all,
Just got a low voltage anti-fog shower mirror. Instructions say to place a box behind the mirror. But then the box would be burried. I have the transformer in a dry location on a switched outlet and wanted to run the wires directly to the dry location? In other words no box directly behind the mirror.

Thanks in advance...

Top
2014 / 2011 NEC & Related Books and Study Guides
#201780 - 06/23/11 01:26 PM Re: Heated Shower Mirror [Re: ptfw30]
renosteinke Offline
Cat Servant
Member

Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
It would be a major help to have the instructions available for review.

Here is a link to one such product: http://www.plumbingstore.com/clear-mirror-installation.html#shower

UL lising or not, I see this as a code-compliant installation only if the mirror is in a damp location (over the sink, not in the shower), and the mirror is removable.

Note that the instructions are silent as to reattaching the mirror to the wall. IMO, the common practice of attaching the mirror with caulk would not be allowed, as it would make the box inacessable.

The access issue remains the same whether the wire are low voltage or line voltage.

IMO, the mirror needs to be GFCI protected. It is common for bath lights to NOT be GFCI protected. This sets the stage for an unprotected mirror, as they want you to tie into the light feed.

Top
#201781 - 06/23/11 02:41 PM Re: Heated Shower Mirror [Re: ptfw30]
ptfw30 Offline
New Member

Registered: 06/23/11
Posts: 3
Loc: NY
Its the same mirror...

* Mirror is in a wet location (in shower)
* Mirror is glued into place, per the instructions.
* Mirror is powered by a remote x-fmr (in dry and accessible location)
* I will be using a GFCI breaker for this circuit


I think I will be running the wires to the dry location and box it there. That way its accessible, dry and boxed.


Edited by ptfw30 (06/23/11 02:42 PM)

Top
#201783 - 06/23/11 04:41 PM Re: Heated Shower Mirror [Re: ptfw30]
HotLine1 Offline

Member

Registered: 04/03/02
Posts: 6805
Loc: Brick, NJ USA
ptfw:
First, If no one said it yet...Welcome to ECN forums!!

What you last said...

"* Mirror is in a wet location (in shower)
* Mirror is glued into place, per the instructions.
* Mirror is powered by a remote x-fmr (in dry and accessible location)
* I will be using a GFCI breaker for this circuit


I think I will be running the wires to the dry location and box it there. That way its accessible, dry and boxed."

Sounds like a plan to me.
_________________________
John

Top
#201790 - 06/23/11 07:31 PM Re: Heated Shower Mirror [Re: HotLine1]
sparky Offline
Member

Registered: 10/18/00
Posts: 5545
just an aside here, what can be expected of a line side gfi meant to protect xfomer secondaries?

~S~

Top
#201792 - 06/23/11 08:43 PM Re: Heated Shower Mirror [Re: ptfw30]
ptfw30 Offline
New Member

Registered: 06/23/11
Posts: 3
Loc: NY
HotLine1 wrote...
"ptfw:
First, If no one said it yet...Welcome to ECN forums!!"




THANKS for the welcome and the reply!!

Sparky, you bring up a good point. I would imagine that since the GFCI detects unbalanced return current on the neutral, that any 24 volt secondary anomaly would not be reliably interrupted. A voltage to human contact would probably just look like a bigger load to the primary side, and would not necessarily trip the GFCI.

I do have lighting and switches in or near a wet area, and that is mostly why I have the GFCI.


Edited by ptfw30 (06/23/11 08:44 PM)

Top
#201795 - 06/24/11 04:43 AM Re: Heated Shower Mirror [Re: ptfw30]
sparky Offline
Member

Registered: 10/18/00
Posts: 5545
Quote:
Sparky, you bring up a good point. I would imagine that since the GFCI detects unbalanced return current on the neutral, that any 24 volt secondary anomaly would not be reliably interrupted. A voltage to human contact would probably just look like a bigger load to the primary side, and would not necessarily trip the GFCI.


well, we do it for pools in 680 ptfw, one would think such xformers would have some sort of an amperage limit, but maybe i'm missing some key theory here?

Quote:
I do have lighting and switches in or near a wet area, and that is mostly why I have the GFCI.


I wire baths with 210.11-C-3- exception in mind because people will always be approaching us with some stretch of the 'other equipment' line in it, like you're dealing with

Usually the manufacturers instruction dictate something in the order of "ok in a tub/shower zone if GFI protected"

I don't know how they come about it for xformers


oh and , minding my manners, welcome aboard ptfw

~S~

Top



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals