Should the power wires be overhead or underground? Underground power line feasibility article talks on the feasibility on using underground lines instead of overhead lines. Both underground and overhead lines have their good and bad properties. Burying power lines is not cheap, it is said the cost would be $1M per mile to convert existing →
An electromagnetic field (also EMF or EM field) is a physical field produced by moving electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. It is one of the four fundamental forces of nature. EMF measurement →
It is sometimes suggested that a mains power isolation transformer might be used to solve the ground loop problem. It is true, that many times a mains isolation transformer does help, but not always. A system with properly used isolation transformer is still safe, it can be even safer than system without isolation transformer. Remember →
Grounding and shielding is an often misunderstood process. It is common to hear quotes ranging from “it’s just black art!” to “the rules change all the time!” and “there’s no way to understand it!” These statements are often repeated but not true. There is a process, it hasn’t changed, and the more one knows about →
There has been articles telling that Boeing 787 planes are grounded over safety concerns in USA. The Federal Aviation Administration has ordered U.S. airlines to stop operating the Boeing 787, after a series of battery and fuel system failures have called into question the airworthiness of the newly developed composite aircraft. Japan’s two biggest airlines →
A recent white paper from APC-Schneider Electric authored by Neil Rasmussen takes a hard look at grounding practices and the use of the signal reference grid in data centers. The Grounding and the Use of the Signal Reference Grid in Data Centers paper contends that signal reference grids are automatically specified and installed in data →
Protecting your data center against power failure is crucial to providing maximum availability. Power loss or poor power quality is a major contributor to data center server down time. This task takes more than simply having UPS and a backup power source, such as a generator. Dual Power Paths: A Crucial Element in a High-Availability →
There has been a debate going on for some years if the traditional AC or new DC power distribution is best approach to power a data center. The DC power side has been pushing their technology with claims of quite considerable power savings. In many published articles, expected improvements of 10% to 30% in efficiency →
Ban on incandescent lamps is progressing. Say goodbye to incandescent lamps – soon they are no longer visible in stores. Incandescent light bulb ban has progressed gradually. As early as September last year, the 60-watt incandescent bulbs were banned. The manufacturing of 40W and the weaker light bulbs in the manufacture and importation of the →
Power factor correction devices: Can they really reduce your electricity bill? article tells that so-called “Power Saver Devices” (known by different names) are nothing but Power Factor Correction (PFC) devices that would connect to the mains and improve power factor measured by your electricity meter. The so-called “Power Saving” device may be useful for industrial →