Power and power quality is something we are all acutely aware of. Whether it is because of outages due to natural disasters or unexplained utility blackouts, everyone knows power is something difficult to live without.
Reading through some electrical engineering textbooks written in the 1930s, the term “frequency” is used to describe what is now referred to as the “fundamental electric power frequency,” also known as 60 Hertz (Hz) in North America and some other parts of the world.
At a recent National Electrical Code taskforce meeting dealing with mission-critical facilities relative to scenarios proposed by the Department of Homeland Security, the main concern seemed to be “you can’t test critical facilities.
Home of the NCAA Division I football and basketball Orangemen and the country’s fifth-largest indoor stadium, Syracuse University’s Carrier Dome has been a pressing concern for school officials for several years. The concern comes with good reason.
Unusual circumstances affected the planning for the new Omaha JATC facility. The International Brotherhood of Electrical Workers (IBEW) Local 22 and National Electrical Contractors Association (NECA) Nebraska chapter shared a building and were looking for more space together.
In a recent article, we covered the need for having a “pre-flight check” performed before moving existing or installing new information technology (IT) equipment into a newly constructed computer room.
You have seen them: tall, gangling, steel structures-known as high-tension lines-that transport hundreds of kilovolts. These rights-of-way are used to safely move transmission-level bulk power from the generators to the distribution substations.
Photovoltaic (PV) modules convert sunlight directly into electrical energy. Integrating PV into a building will impact its operation. Not only will the PV system produce electric energy to serve building loads but it can also reduce the building's electric demand and air-conditioning heat load.
Most of the articles in this column have focused on how to find what type of power quality demons are lurking in your power system. However, the other aspect of PQ is how to get rid of them. Otherwise, it is sort of like a doctor who only diagnoses your illness, but can't offer any treatment.
Adjustable speed drives or ASDs, are often categorized as "sensitive" to power quality phenomena, which means ASD could also stand for "another sensitive device." I am still not sure what "sensitive" means relative to hardware. Susceptible seems like a far better choice of words.
Ground-fault circuit interrupter (GFCI) protection for personnel or a similar protection technique has been in the National Electrical Code (NEC) since 1962 with specific reference to GFCI and its definition found in the 1968 NEC.