Electical Contractor

Recently, I fielded a question about the basic statement in Section 695.3 of the 2008 National Electrical Code (NEC) that “electric motor-driven fire pumps shall have a reliable source of power.” The question involved the reliability of the power source for one of the most important electrical motor

A major revision to article 511, covering commercial repair and storage garages, appears in the 2008 National Electrical Code (NEC).

While preparing a presentation, I noticed a photo taken at a facility where temporary power was needed periodically. The facility rented a generator when necessary. It showed a disconnecting means with four individual conductors stubbed out of the bottom of the enclosure.

Article 210 Branch Circuits; Article 240 Overcurrent Protection; Article 250 Grounding and Bonding; Article 310 Conductors for General Wiring; Article 450 Transformers and Transformer Vaults (Including Secondary Ties); Article 480 Storage Batteries Aluminum conductors with AFCIs

When installing recessed fixtures, carefully consider the location of the units. The presence of combustible materials surrounding the luminaire is very important, and recessed lights can act as chimneys for heat loss and moisture transfer into attic spaces.

The 2008 National Electrical Code (NEC) includes a new definition covering “Intersystem Bonding Termination” and a total rewrite of Section 250.94 covering the requirements for installing a bonding connection point for communications systems.

Article 220 Branch Circuit, Feeder, and Service Calculations; Article 240 Overcurrent Protection; Article 250 Grounding and Bonding; Article 404 Switches; Article 700 Emergency Systems; Guide Information for Electrical Equipment Directory (White Book) published by Underwriters Laboratories Inc.

Selecting the correct size conductor involves referencing more than one section and more than one chapter in the National Electrical Code (NEC). The following questions must be answered before selecting conductors.