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.
I just returned from chairing the Report on Proposals (ROP) meeting for the NFPA 70B Recommended Practice for Electrical Equipment Maintenance Committee, where we reviewed, debated, commented and voted on more than 150 proposed revisions to the 2002 edition for the next edition.
As the Great Blackout of 2003 rolled through the Northeast and Midwest, a lot of people were left in the dark. But the blackout turned on the lights for a group of National Electrical Contractor Association (NECA) member contractors in Michigan. They saw the blackout as opportunity knocking.
If your firm does telecomm work, this is worth reading. Although it has been talked about for several decades, modulated radio frequency communications over power lines never really took off because there were difficult technical challenges and no cost-effective solutions. No more.
The electrical contractor's job on a typical construction project goes beyond the scope of traditional electrical installations. It's a two-part responsibility that includes the construction or renovation of electrical systems for the structure.
Simple questions to tackle audits or troubleshooting jobs Last month's article focused on having the right tool for the job. When conducting a power-quality audit or carrying out a troubleshooting job, the right tool is just one part of the process.
It can save hours of work and a lot of money While doing some construction work recently, I needed a tool that was in my truck, but didn’t feel like going to get it. So I tried to “make do” with what I had in my toolbox.
Article 210 Branch Circuits Article 250 Grounding Article 310 Conductors for General Wiring Article 320 Armored Cable: Type AC Article 404 Switches Derating Cables Q: Is it necessary to derate types NM-B, AC or MC cables where these cables are bundled to enter a branch-circuit panelboard?
Dedicated 20-ampere branch circuits are required Most dwelling units are required to have a laundry area within the living area or have a laundry area provided on the premises for a multifamily building.