A typical low-voltage variable-frequency drive. Industrial facilities commonly use variable-frequency drives (VFDs) to control the speed at which alternating current motors operate. Let’s examine a ...

I continue to be surprised by how many equipment designers are confused by UL circuit protection standards. In trying to meet conflicting standards, engineers may actually decrease the level of ...

For the PDF version of this article, including diagrams and/or equations, click here. In any off-line flyback converter design, it is possible that the output ...

Each motor branch circuit must be protected against short circuit and ground faults by an overcurrent device sized no greater than the percentages listed in Table 430.52. A branch-circuit ...

A German research team has developed a semiconductor-based protection concept tailored to renewable energy systems that forces a permanent short circuit in less than 1 millisecond in the event of a ...

Have you ever wondered why a car’s city fuel economy is always lower than its highway fuel economy? Most cars spend a lot of time stopping or traveling at low speeds, especially in a city. Start-stop ...

The objective of protective relays and protective schemes is to protect electrical equipment such as transformers, lines, cables, bus bars, etc. during abnormal system conditions. Hence, protective ...