The first earth tester was invented in the year 1950 by Evershed and Vignoles Meggers who made the initial insulation as well as earth resistance testers. Analog grounding tester like М416 is the most frequently used in the USSR. Many organizations from the 21st century manufacture digital earth resistance meters as well as testers. The main function of this instrument is to decide the capability of the grounding for an electrical system. By a NEC … [Read more...]
Moving Iron Instrument : Working, Types, Torque & Its Applications
The moving iron instrument is the most commonly used ammeter & voltmeter used at power frequencies in laboratories or switchboards. These types of instruments are designed in such a way to measure voltage & current to the accuracy required in most engineering works. As compared to any other types of AC instruments with the same accuracy & ruggedness, these are not expensive. So this article gives brief information on a moving iron instrument – … [Read more...]