MG320 Insulation tester / Multimeter

The Extech MG320 CAT IV insulation tester/true RMS multimeter combines a portable 20GΩ/1000V insulation tester with a True RMS Multimeter. Insulation tester includes PI/DAR modes, programmable timer, and a comparator for custom test configurations and quick results. Multimeter functions include AC/DC Voltage, resistance, and continuity test. Manually store/recall up to 99 readings. Designed with rugged housing and large backlit 6,000 count LCD with an analogue bar graph. Complete with test leads, alligator clip, 6 x AA batteries, and soft case.


  • Measure Insulation Resistance to 20GΩ
  • 5 Test Voltage ranges
  • Polarization Index (PI) and Dielectric Absorption Ratio measurements (DAR)
  • Low Resistance measurement with Zero function
  • Programmable Timer feature sets the duration of test
  • Comparison Mode allows user to set the Pass/Fail values for insulation measurements
  • Step Voltage (10% steps at 50% to 120% of range)
  • Auto-discharge of voltage test signal
  • Lock Power On Function for hands-free operation
  • Manually store/recall up to 99 readings
  • Backlit 6,000 count display with analog bargraph
  • High voltage and overload indication
  • Data Hold to freeze displayed reading
  • Auto Power Off and Low battery indication
  • Complete with test leads, alligator clip, 6 x AA batteries, and soft case

Customer Service

Erik-Jan Visser