Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: NEC and Today's Technology?  (Read 1657 times)
W0FM
Member

Posts: 2056




Ignore
« on: November 07, 2012, 01:59:22 PM »

I had an unfortunate discovery last weekend while finishing up a kitchen remodel.  While replacing under cabinet lighting (120 VAC) I found that my pea-brained home builder apparently let his equally pea-brained common laborer install my cabinet lighting.  A sharp, "custom" hole drilled in the back of the light fixture for the Romex entry had, over time, nicked through the insulation on the hot lead.  Not the wire.  But I could see where arcing had occured around the hot lead and the fixture hole.  The fixture was properly grounded.  Probably the best sight for my eyes at the time, but still a scary thought.

There is not enough 14/2 hot lead to cut it back and "lose" the tiny nick and I knew what that meant.  But I searched the internet for a solution nontheless.  Being a ham for 50+ years and having built and wired many HV instruments and ham shacks, my thoughts naturally evolved around "creativity", but always returned to safety.  Obviously, there are only a couple of code-approved fixes in Missouri and most other states.  I can do a "two-box splice" or pull the Romex out of the wall and replace it altogether.  Either way, a gut-wrenching thought while looking at brand new tile backsplash and granite countertops.

So, to my point.  I know that technology has evolved to produce tough shrink tubing with voltage, temperature and fire ratings equal to or better than my 17 year old 14/2 Romex house wiring insulation.  So why does the National Electrical Code not allow for this type of repair?  Does it typically take a very long time for the Code to be updated to products available in today's technology?  A quick Google search revealed many examples of high-rated, UL approved, industrial shrink tubing.

I know a lot of elecrician hams watch these posts.  I would never jeopardize the safety of my family or my home.  A licensed electrician will be out in the morning to do whatever has to be done to replace this line to Code.  But I'm not thrilled at the thought and I sit here scratching my head about the technology and today's NEC.

73,

Terry, WØFM   
Logged
W6EM
Member

Posts: 832




Ignore
« Reply #1 on: November 07, 2012, 06:22:45 PM »

By chance, do you have space above the cabinets?  Or, room to put a box in the back of a top shelf?

If you do, you could convert the undercabinet lighting to either low voltage halogen or LED bar lights and plug in the small  transformer/switching supply to the box and run LV wiring behind the cabinets instead of all the costly rip-out/rebuild.

Lee
Logged
W0FM
Member

Posts: 2056




Ignore
« Reply #2 on: November 07, 2012, 07:00:12 PM »

Good point Lee. Unfortunately it is one of the first 6 possible solutions I listed for myself.  The upper cabinets go all the way up to the ceiling with crown molding on top.  The underside of each of the 10 cabinets (18", 24", 36") are already individually wired for line voltage (120 VAC).  Changing to low voltage would be easy, except for the fact that the existing 120V lines centered under each cabinet would still need to be removed or "capped" to meet Code.  I could do that with blank junction boxes under each cabinet, but that would still require un-nicked line wiring going into the junction box.

Yes, I could pull each upper cabinet, their contents and crown molding and carve up the drywall and studs, but its a large kitchen and it would be a huge task at this point in the project.  Which is another reason why a I am disappointed that a heat shrink insulation option, of the same specs as the existing house wiring insulation, looms so disappointing in my thinking.

Terry, W0FM
Logged
NI3S
Member

Posts: 67




Ignore
« Reply #3 on: November 07, 2012, 09:49:09 PM »

Can you remove the entire fixture?  If so, drill the hole to 7/8" and use a proper strain relief / wire protection device in the correctly sized (for electrical stuff) hole.  Obviously, turning the power off to the device, and safely disconnecting the wires are a prerequisite.

A $1 part to hold the Romex in place may be all that is needed. 

On another note, thank goodness this was found before it caused the loss of life or property. 
Logged
K2DC
Member

Posts: 1377


WWW

Ignore
« Reply #4 on: November 08, 2012, 03:55:38 AM »

Terry,

   To answer your question,  the NEC is on a 3 year revision cycle.  Submissions, comments, review and revision are all scheduled for next year with the update to be released in 2014.  And it's like any other bureaucracy - it usually takes overwhelming evidence and a phone call from God to get a change approved.

73,

Don, K2DC
Logged
WX7G
Member

Posts: 6146




Ignore
« Reply #5 on: November 08, 2012, 06:56:15 AM »

NEC is behind the times, so to speak. UL allows heat shrink tubing as the insulation on 120 VAC wiring inside electronic equipment. The UL requirement is to use double insulation such as insulated wire with heat shrink over it or two layers of heat shrink. This can be found in UL60950.
Logged
W0FM
Member

Posts: 2056




Ignore
« Reply #6 on: November 08, 2012, 08:36:16 AM »

NI3S - the old fixtures were already down.  The new fixtures did come with strain reliefs for the knock-outs, although, probably not the expensive $1.00 version you might have been envisioning  Grin 

K2DC - Don, that was the feeling I had but I had no idea of why it would take so long.  Like anything else that MOVES slowly: BUREAURCRACY!

WX7G - Spot on.  The electrician explained to me this morning, that, because the nicked insulation would be inside the fixture, at the end of the branch and feeding no other circuits, he could simply repair it with good electrical tape or heatshrink.  Had it been inside the wall or a junction box it would require more.

My problem is solved and I can enjoy my new lights while I wait for the Code to catch up with technology.  Thanks to all for the somewhat OT bandwidth.

73,

Terry, WØFM
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!