• Test Voltages of 250V, 500V, and 1000V
  • Measure insulation resistance to 5.5GΩ (autoranging)
  • AC Voltage measurement from 30 to 600V
  • Polarization Index measurement (PI)
  • Dielectric absorption ratio measurement (DAR)
  • 10MΩ internal resistance test
  • Low Resistance measurement with Zero function
  • Continuity beeper
  • Large 2000 count dual display with backlight
  • High voltage and overload indication

What's in the Box

  • Test leads
  • Alligator clips
  • 6 x AA batteries
  • Hard cover
  • Soft carrying case


The Extech MG310 Digital Insulation Tester allows quick and easy testing/troubleshooting of motors, transducers, and other industrial appliances. Wide range measurement up to 1000V with Insulation Resistance to 5.5GΩ. Includes an easy snap on protective hard cover and soft pouch to conveniently transport your meter and accessories to the next job site or to safely store away.

In Stock

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This stock is typically available to ship in 3 - 5 working days.

Part Number Price Available
$234.29 16 in stock

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