Extech MG500 Digital High Voltage Insulation Tester

Extech MG500 Digital High Voltage Insulation Tester


The Extech Digital Insulation Tester will measure insulation resistance from 800k ohms to 500G ohms.


  • EnerSave™ limits test duration to 10 seconds to save energy
  • Designed inside a rugged hard case and includes heavy duty test leads and alligator clips
  • Warning of external voltage presence (>500VAC or VDC)
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This Digital Insulation Resistance Tester will measure insulation resistance from 800k ohms to 500G ohms using dynamic auto-ranging technology. Test voltages range from 500V to 10kV in 500 volt steps. It also employs an auto-discharge utility: upon completion of a test, the instrument will automatically discharge all capacitive and inductive circuits charged by the tester. The discharge can be observed on the instrument's bargraph display.


When the instrument is first powred on, a test circuit applies a heavy current draw on the batteries for a few seconds and measures the voltage in order to determine the capacity of the battreries. A bar graph displays the voltage that is stressing the insulation during the first 30 seconds of a test and during the discharge of the circuits at the end of the test. The display will also show the elapsed time from the start of the test and the total time, even after the testing has stopped.

Notable Specifications:
  • Insulation Resistance: 800kΩ to 500GΩ ( Autoranging )
  • Resolution: 1kΩ
  • Basic Accuracy: ±5%
  • Test Voltages: 500VDC to 10kVDC (adjustable in 500V steps)
  • Preset Buttons: 1kV, 2.5kV, 5kV, 10kV
  • Polarization Index: Yes
  • Dielectic Absorption Ratio: Yes
  • Voltage Output Warning: Yes
  • Automatic Discharge: Yes
  • Dimensions: 13x10.2x6.3" (330x260x160mm)
  • Weight: 7.9lbs (3.6kg)
What's Included:
  • (1) Heavy duty carrying case with cover
  • (1) Test leads
  • (1) Alligator clips
  • (8) C batteries
Image Part # Product Description Price Stock Order
Extech MG500 Digital High Voltage Insulation Tester MG500 Digital high voltage insulation tester
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