The ratio of two time-resistance readings (such as a 60-second reading divided by a 30-second reading) is called a dielectric absorption ratio. It is useful in recording information about insulation. If the ratio is a 10-minute reading divided by a 1-minute reading, the value is called the polarization index.
With hand-cranked instruments, it is easier to run the test for only 60 seconds, taking the first reading at 30 seconds. When using line-operated instrument, you will get best results by running the test 10 minutes, taking readings at 1- and at 10-minutes, to get the polarization index.
The 1026 Digital Megohmmeter is a compact, lightweight, battery-operated , hand-held meter. It provides four functional tests, and is a megohmmeter, DC voltmeter, AC voltmeter, ohmmeter and a continuity tester.
The DM-III Power Quality Analyzer with 3000A Current Probes provide the essential functions and capabilities required to operate accurately and effectively in today’s demanding electrical environments.
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Offering CAT IV, the MIT525 is compact, light 5 kV insulation resistance tester for the diagnostic testing and maintenance of high voltage electrical equipment.
The MIT1025 Insulation Resistance Tester measures insulation resistance, voltage, current, and capacitance in high-voltage electrical systems.