A Megger insulation tester can be used to perform three different types of insulation resistance tests, short-time or spot-reading, time-resistance and dielectric absorption ratio. Each test varies with results and is used for particular purposes. To help you get a better understand of what each test is and how a Megger test can be used.
Understanding the factors that can affect Megger insulation testing readings is very important. There are a number of things that can affect current, such as temperature and humidity, but also time. When a current flows along and through insulation, it is made up of a relatively steady current in leakage paths over the insulation surface.
Whether you use a Megger insulation tester monthly, twice a year, or once a year, it is important to be able to interpret the results. Megger insulation tester readings should be considered relative and are known to be quite different with each reading. For example, you may test one piece of equipment three days in
A Megger insulation tester is a small, portable instrument that gives a direct reading of insulation resistance in ohms or megohms. Essentially, a Megger insulation tester is a high-range resistance meter that consists of a built-in direct-current generator. The Megger insulation tester is specially constructed with both current and voltage coils, which enables the device