If Art. 680 of the National Electrical Code (NEC) has one overriding concern, it's to keep people and water separated from electricity. Article 680 applies to pools, spas, hot tubs, fountains, and similar bodies of water....More
Looking at Fig. 230.1 in the NEC, we can see that the second and third major areas of Art. 230 provide requirements for service entrance conductors (Part...More
If you look at Fig. 230.1 in the NEC, you'll see that Art. 230 divides neatly into three general of coverage. The first includes general requirements,...More
In order to create safe working conditions, OSHA and the NEC provide working space requirements that vary according to the hazards involved with...More
The sizing requirements for pull boxes, junction boxes, handhole enclosures, and conduit bodies exist to prevent conductor insulation damage. Those requirements...More
Raceways must be large enough to hold conductors without overheating and avoid insulation damage during conductor pulls. Therefore, we must determine the maximum number and size of conductors to put in a given raceway. That limit is what we mean by raceway fill....More
Every commercial occupancy needs a form of identification, the standard method of which is typically the electric sign. This is one reason why you'll be working with Art. 600 if you do much commercial or industrial work....More
The operation of any facility depends on power distribution, which, in turn, depends on transformers. Safe and reliable operation of transformers is crucial...More
Considering the fact that it has nine parts, at first glance, Art. 424 might seem like overkill for a device as simple as a heater. Walk into any hardware...More
Separately derived systems (SDSs) include most transformers as well as any generator or UPS supplying a transfer switch that opens the neutral conductor....More
Similar to feeder taps, covered in the last issue, transformer secondary conductors can be every bit as confusing. Let's take a closer look at 240.21(C)...More
LEDs have unique and compelling characteristics that make them ideal for industrial lighting applications. But there are a variety of misconceptions about LEDs, how well they work, how long they last, and more. Digital Lumens developed this whitepaper to dish up the facts around LEDs and address some common misunderstandings....More
An arc flash is associated with the explosive release of energy caused by an electrical arc, due to either a phase-to-ground or a phase-to-phase fault. This kind of fault can result from many factors – a dropped tool, accidental contact with electrical systems, buildup of conductive dust, corrosion or improper work conditions.....More
Abstract: In this webinar, Mike will not only explain the current NEC requirements for GFCIs and AFCIs, but he'll explain how they operate, what causes their premature failure, and when they won't provide the safety protection you might have thought they would.
Abstract: This webinar will teach attendees the difference between risk and hazard, and how the choice of system grounding has a direct impact on reliability and safety.
