When a Compliance Safety and Health Officer (CSHO) from the Occupational Safety and Health Administration (OSHA) visits an unprepared job site, the reactions can be amusing. Usually, the word travels throughout the site and employees scramble.
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.
Ground-fault sensing and relaying equipment is intended for use in power distribution systems rated at 600V maximum and are considered to be equipment protection devices, not personal protection devices.
Many changes have occurred to the National Electrical Code (NEC) since the first NEC was published on Aug. 31, 1897. Even though the electrical industry was in its infancy, this “first” NEC was remarkably insightful and has withstood the test of time.
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).
At one time or other, all contractors have been faced with a decision to either recalculate the size of an existing service or feeder or just guess at the amount of spare load and install new circuits while hoping for the best. Guessing will usually only get you in trouble.
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.
When considering the various financial institutions we personally deal with each day, such as banks and investment corporations, we immediately think of how much security is involved to protect the financial assets held in, or controlled by the institution.
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 of today’s electrical contractors are constantly trying to expand their offerings. In an effort to increase their marketability, these contractors are seeking certifications to broaden their knowledge base.
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.
Supplemental and supplementary grounding electrodes are very similar in name but vastly different in their permitted uses. Understanding the differences in these two electrodes can be critical in providing a safe, Code-compliant installation.
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.
The new type of GFCI employing the latest technology comes with a caveat that must be brought to our attention. Do not get the impression that if this type of receptacle is wired incorrectly that a person cannot be killed or injured.
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