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 electrical safety questions.
A recent electrical inspection uncovered this section of metal wireway in the attic of a tall building. Not only was the wireway missing its covers, but someone had also used the area as a trash receptacle. This would undoubtedly add to the fuel load in this space if a fire were to break out nearby. In addition, the blocks used to support the conductors weren't a recognized method of installation. Sec. 376.2 defines a metal wireway as a sheet metal trough with a hinged or removable cover used to house and protect electric cables that are laid in place after the wireway has been installed as a complete system. Installing wireways as a complete system will ensure that they're properly grounded [250.118(14)].
This metal duct is located in a working space that should be kept clear of obstructions. The minimum depth of working space in front of electrical equipment may not be less than 3 ft. In addition, the minimum headroom of working space about electrical equipment must comply with 110.26(A)(3). The height of the working space must be clear and extend from the grade, floor, or platform to the height required by 110.26(E), which cannot be less than 6½ ft for service equipment, switchboards, panelboards, or motor control centers. In addition, if the electrical equipment is taller than 6½ ft, the minimum headroom can't be less than the height of the equipment.
If you look close, you'll see that someone used a bent “fender washer” to fill in the extra space at the C-phase feeder conductor termination in this overcurrent protection device. In fact, even though you can't see them, the other two phases are terminated in the same fashion. This isn't a recognized method of installation and creates a serious hazard. This installation violates the rules in 110.14, which states conductors of dissimilar metals can't be intermixed in a terminal or splicing connector.
This installation is located over an exit door in a large auditorium where more than 200 electrical industry representatives recently attended an industry meeting. Several attendees took a picture of this liquidtight flexible metal conduit that was missing a connector. Only time will tell if this unsafe installation will still be there when the meeting reconvenes next year. The missing fitting violates basic rules related to grounding and workmanship. See 250.4 for general requirements for proper grounding and bonding.
Now you can send Code Violations Illustrated stories and photos directly to Joe Tedesco at:
Joe Tedesco
350 North Street
Boston, MA 02113
or e-mail: [email protected]
If you mail pictures, please include the story, location, and some information about yourself — and please do not write on the front or back of your photo. Please send all digital images in JPEG format. You can send photos while visiting Joe's Web site at: www.joetedesco.com
