ECM Buyers' Guide

Illustrated Catastrophes

Sep 1, 2003 12:00 PM, By Joe Tedesco, NEC Columnist


         Subscribe in NewsGator Online   Subscribe in Bloglines     


As usual, never consider the following commentary associated with these photos as a formal interpretation of the National Electrical Code (NEC). Without criticizing anyone or any product, the following scenarios present us with serious safety questions.





THIS IS NO GARDEN OF EDEN

Cliff Weedman of Eighty Eight, Ky., found this installation in a botanical garden in Nashville, Tenn. The first thing you may notice is that in order to operate the switch on the combination device you would have to reach through the water falling off the evaporative air cooler above (you can actually see the drops falling in the photo) — not to mention the lack of a cover. And it just gets worse: the open cover on the GFCI, PVC plumbing fitting used as conduit, open knockouts, inaccessibility due to plantings, non-rain tight wireway, and improperly supported boxes are all evident. To top it off, it's all within easy reach of the public, including small children. The location — under the overflowing water trough — is unsuitable for any installation of electrical equipment.




THIS NAIL WAS APPROVED

The 2002 Code permits use of a circuit breaker as a disconnect. For a multiwire branch circuit, unless limited by 210.4(B), individual single-pole circuit breakers, with or without “approved” handle ties, are permitted as the protection for each ungrounded conductor of multiwire branch circuits that serve only single-phase, line-to-neutral loads. A proposal for the 2005 NEC [ROP 10-39] was accepted to delete the word “approved” and replace it with the word “identified” because Art. 100 defines “approved” as acceptable to the authority having jurisdiction. Some electrical inspectors have accepted nails, screws, or wires as an approved handle tie. Art. 100 defines “identified” as “recognizable as suitable for the specific purpose, function, use, environment, application, and so forth, where described in a particular code requirement.” Accessories, such as handle ties, are readily available from product manufacturers.




CLEAR AND PRESENT DANGER

A revision to 110.12(A) in the 2002 NEC requires only “cable and raceway openings” to be effectively closed to afford protection substantially equivalent to the wall of the equipment. It's obvious that some workers believe this rule also applies to panelboards. An accepted change proposal for 110.12(A) of the 2005 NEC (ROP 1-160) will add additional language to include “unused openings for circuit breakers and other overcurrent devices in addition to raceway and cable openings, adding auxiliary gutters, cabinets, cutout boxes, meter socket enclosures, equipment cases, or housing openings.” This change will make it clear that this type of installation will never again be acceptable.




MOBILE AC UNIT

An AC unit isn't designed to be installed in a door. Underwriters Laboratories listings (UL 484) include room air conditioners, which are to be encased in assemblies designed as a unit and intended as the prime source of refrigeration and dehumidification for a single room, zone, or space. A room air conditioner is intended for installation in windows, through walls, or as consoles located in or adjacent to the room, zone, or space to be conditioned, not placed in a door. In addition, this also violates 110.3(B) of the 2002 NEC, which states “listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.”


Commenting terms of use blog comments powered by Disqus

Want to use this article? Click here for options!

product of the week

Thermal imaging software

November 17, 2008 10:26 AM

Fluke SmartView Version 2.0

View all 2008 Products of the Week

Recent Comments

Follow comments on ecmweb.com




Arc Flash Conferences   Code Change Conferences

Professionals provide answers to your questions.



Do you have any technical paper explaining IBC?

iGard Resistance Grounding Q&A BookletDownload the Resistance Grounding Q&A Booklet
I-Gard
EC&M TV

Arlington Indoor InBox

Easy install makes Indoor InBox preferred for power & low voltage applications. Furniture and appliances stay close to the wall!...

Listen
"Sizing Gen-Sets: Facts, Hints, and Good Judgment"
Listen
Sponsored By:

resources

product info icon

product info

tradeshow icon

tradeshow

research icon

research

rss icon

rss

Back to Top

Browse Back Issues

Browse Back Issues