Electical Contractor

The arc-fault circuit-interrupter (AFCI) has been around for three National Electrical Code (NEC) cycles and, with the advent of the new 2005 NEC, will have been present in three editions, although with various changes within each edition.

Redundantly grounding all electrical equipment in a patient care area has provided one of the most critical pieces of a very complex puzzle involving patient protection.

As you may know, the Telecommunications Industry Association (TIA) has agreed that Level III-qualified testers are to be used when certifying or verifying Category 6 cabling systems (Category 6 cable is a 100-Ohm cable with transmission characteristics specified up to 250 MHz).

This is the conclusion of a two-part article that began in the November issue. This part provides important information for listing and National Electrical Code requirements for installations of emergency, legally required standby and optional standby systems.

This is the first of two parts about installing emergency, legally required and/or optional standby systems. This first part will cover the basics of the three systems and the second part will cover requirements for transfer equipment.

Many new concepts in lighting control ARE being used by designers and electricians, while other new designs are still relatively unknown.

If you missed it, the Telecommunications Industry Association (TIA) TR 42 committee meetings were held in early June. It’s time to pay attention, since many of their decisions can affect the contractor, as you’ll see below.

Parallel conductors are often installed where large ampacity feeders or services are used. Total understanding of the paralleling requirements permitted in the National Electrical Code is necessary before attempting to design a large electrical system or install these conductors.

A luminaire is defined in Article 100 as “a complete lighting unit consisting of a lamp or lamps together with the parts designed to distribute the light, to position and protect the lamps and ballast (where applicable), and to connect the lamps to the power supply.” Since luminaires (lighting fixtu