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What's Wrong Here?

Feb 13, 2007 12:48 PM, By Joe Tedesco

Answer:

Hint: Attack of the terminations

Gary Dennington, a project manager with Fox Systems, Inc., ran across this mess during a data gathering excursion at an industrial facility as part of an arc flash survey. “What you can see is a main 600A service, 120/240V delta somewhat parallel service,” says Dennington. “All the secondary distribution is fed through a trough. Some travel out of sight. A few disconnects are mounted on the wall. I guess they could not defeat the opening mechanism, so they cut the cover.”

I’ve noted some of the sections of the Code that have been violated. I could go on to add rules from Chapter 3 as well, but the summary page would run way too long.

110.14 Electrical Connections. “Because of different characteristics of dissimilar metals, devices such as pressure terminal or pressure splicing connectors and soldering lugs shall be identified for the material of the conductor and shall be properly installed and used. Conductors of dissimilar metals shall not be intermixed in a terminal or splicing connector where physical contact occurs between dissimilar conductors (such as copper and aluminum, copper and copper-clad aluminum, or aluminum and copper-clad aluminum), unless the device is identified for the purpose and conditions of use. Materials such as solder, fluxes, inhibitors, and compounds, where employed, shall be suitable for the use and shall be of a type that will not adversely affect the conductors, installation, or equipment.” FPN: Many terminations and equipment are marked with a tightening torque.”
(A) Terminals. Connection of conductors to terminal parts shall ensure a thoroughly good connection without damaging the conductors and shall be made by means of pressure connectors (including set-screw type), solder lugs, or splices to flexible leads. Connection by means of wire-binding screws or studs and nuts that have upturned lugs or the equivalent shall be permitted for 10 AWG or smaller conductors. Terminals for more than one conductor and terminals used to connect aluminum shall be so identified.”
110.16 Flash Protection. “Switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers that are in other than dwelling occupancies and are likely to require examination, adjustment, servicing, or maintenance while energized shall be field marked to warn qualified persons of potential electric arc flash hazards. The marking shall be located so as to be clearly visible to qualified persons before examination, adjustment, servicing, or maintenance of the equipment. FPN No. 1: NFPA 70E-2004, Standard for Electrical Safety in the Workplace, provides assistance in determining severity of potential exposure, planning safe work practices, and selecting personal protective equipment. FPN No. 2: ANSI Z535.4-1998, Product Safety Signs and Labels, provides guidelines for the design of safety signs and labels for application to products.”