Virtually all hand-held insulation testers offer two discrete test functions: insulation and continuity. The core function, of course, is the insulation test, a high-voltage measurement of the quality of insulating material in electrical equipment. The unit of measurement is the Megohm (MΩ) and these testers can correctly be termed megohmmeters as well as insulation testers.
The short answer? Nothing. They’re still here. Like Ford’s Model T is to automobiles, nothing more symbolizes the revolution in electrical testing and maintenance that began around the turn of the 20th century than the hand-cranked insulation tester.
Insulation testers typically offer a discrete number of selectable test voltages, with 250, 500 and 1000 V being common selections. Until recent improvements in microprocessor technology, it was largely just assumed that the selected voltage was actually being realized across the test item. That may not have been so. Working in opposition to the test voltage is the amount of current being drawn, and since these instruments are being used to test insulation, the amount of current…typically only a couple milli-amps…could be restricted for safety and economy.
Arguably, circuit breakers are some of the most important components in modern electric power systems. They break off current when a fault occurs. And although circuit breakers are not thought about much and are often taken for granted, they play a VERY important role in keeping power flowing. Circuit breakers need to operate within extremely tight tolerances when a disturbance is detected in the network they are attached to, in an effort to protect sensitive and costly components and equipment like transformers.
Mike Palmer, Megger’s Western regional sales manager, conducted a hands-on safety demo at Dynalectric’s yearly safety fair held in San Diego, California on Saturday, February 7. 175 apprentices and journeyman electricians attended the event.
Once again, the Megger distributor charity golf outing produced record-breaking figures. The 14th annual event, held on Saturday, January 24 at the Lakes of Ahawatukee Golf Course in Phoenix, Arizona, raised $5,500, an incredible 40% increase from last year.
Electrical safety is not a matter to be taken lightly, especially in the workplace. When proper precautions are not taken, electrical hazards may occur resulting in serious injury or even death.
There used to be a time when things were simple. There were only six channels to choose from on television (and all signals came through an antenna), telephone lines were simply wired and there was no such thing as the internet. Maybe I am exaggerating, but the truth is, people – more specifically technicians – just didn’t need to know as much as they do now and certainly didn’t need very specialized training or tools to do their jobs.
Soil resistivity testing is a standardized means of measuring and evaluating soil for its electrical properties. It is most useful in grounding, as a means of gathering data that is used in designing an effective ground electrode. This provides a valuable alternative to the drive-and-test method where ground rods are coupled and driven deeper, or added to a grid structure, and tested for resistance after each implementation until the required or specified resistance is achieved. Resistivity measurements can be entered into calculations along with the desired ground resistance and the complete electrode thereby designed before installation begins.
I hear the word time domain reflectometer (TDR) and for some reason visions of the DeLorean time machine fitted with a flux capacitor comes to mind, you know, needing to generate 1.21 ‘gigawatts’ of electricity. A time domain reflectometer just sounds like something Doc Brown would have used to travel back to the future.