Electical Contractor

In 2001, PFPC Inc., a leading provider of processing, technology and business solutions to the global investment industry and a member of the PNC Financial Services Group Inc., decided to expand its operations by adding a four-story, 116,000-square-foot worldwide headquarters building to its existi

A couple of months ago we dealt with lightning and the fast transients that can be coupled onto the electrical distribution system of the utility or within a facility, and the use of TVSS (transient voltage surge suppressors) to minimize the potential damage from such.

CODE CITATIONS Article 220 Branch-Circuit, Feeder and Service Calculations Article 230 Services Article 240 Overcurrent Protection Article 310 Conductors for General Wiring Article 312 Cabinets, Cutout Boxes and Meter Socket Enclosures Article 404 Switches Article 410 Luminaires (Lighting Fixtures)

210.70(A)(2) Lighting Outlets Required Lighting outlet and wall switch provisions for dwelling units, guest rooms (hotel, motel and similar occupancies) and certain areas in non-dwelling occupancies are covered in 210.70(A) through (C).

210.70(A)(2) Lighting Outlets Required Branch circuit requirements are covered in Article 210 of the National Electrical Code. Part III of Article 210 covers required receptacle outlets and lighting outlets.

CODE CITATIONS Article 110 Requirements for Electrical Installations Article 230 Services Article 240 Overcurrent Protection Article 250 Grounding Article 310 Conductors for General Wiring Article 400 Flexible Cords and Cables Article 406 Receptacles, Cord Connectors and Attachment Plugs (Caps) Arti

Consider the following statements summarized from a description of a “recent” blackout: • Needles on meters in utility control centers were swinging wildly.

CODE CITATIONS Article 110 Requirements for Electrical Installations Article 250 Grounding Article 334 Nonmetallic-Sheathed Cables: Types NM, NMC and NMS Article 422 Appliances Article 517 Health Care Facilities Article 680 Swimming Pools, Fountains and Similar Installations Grounding a feeder circ

The frequency stability of the interconnected electric grid in North America is a marvel of engineering. As shown in Figure 1, the deviation is rarely beyond 0.05 Hz from the nominal 60 Hz. In fact, during a given hour time period, this deviation is more like +/-0.02 Hz from the nominal value.