Customize Product

Insulation Tester/MultiMeter with Wireless PC Interface – Extech


Extech MG300 / MG302 CatIV Insulation Tester / Multimeter Combines a 1000V Insulation Tester With a full-featured True RMS MultiMeter

Extech Instruments MG300 is a true RMS multimeter with built-in insulation resistance tester and the added safety of wireless data streaming for remote monitoring and data logging. By adding insulation testing capabilities to the ubiquitous digital multimeter, electricians are always equipped for insulation testing, helping to make it a more routine part of predictive maintenance with faster troubleshooting and repairs without additional tools.

The rugged and waterproof (IP67-rated) combination meter includes a digital insulation resistance tester (or megohmmeter) with 4 different test voltages for measuring resistance up to 4 GΩ with 0.001MΩ resolution. The full-function, true RMS digital multimeter includes useful extras like duty cycle measurements and milliamp readings for analog 4-20mA current loops in industrial analog process controls. The CAT-IV-rated meter’s wireless data streaming enables safer troubleshooting and maintenance on dangerous moving equipment and one-person operation of remote safety switches. Technicians can focus on finding problems by monitoring real-time readings on a laptop or computer screen from safe distances – up to 30 feet away. The meter comes complete with remote USB receiver, Windows® compatible software, test leads with alligator clips, Type K bead wire temperature probe with adapter, carrying case, and 6 x AA batteries. The MG300 is available with NIST-traceable certification (model MG300-NIST).


  • Wireless USB interface transmits measurement data to a PC
  • Backlit super large triple display
  • 125V, 250V, 500V, and 1000V test voltages
  • Insulation Resistance from 0.001MOhm to 4000MOhm
  • Auto discharge of capacitive voltage
  • Lock Power On Function for hands-free operation
  • Data Hold, Min/Max, Relative mode, Auto power off

USA, Mexico, and Canada use 915MHz model MG300 and majority of other countries use 433MHz model MG302

Comes complete with remote receiver with USB cable, Windows compatible software, test leads with alligator clips, Type K bead wire temperature probe with adapter, carrying case, and 6 x AA batteries


This product is currently out of stock and unavailable.

products found
Item # Description
EX/MG300Insulation Tester/True RMS MultiMeter w/Wireless PC Interface (915MHz)
EX/MG302Insulation Tester/True RMS MultiMeter w/Wireless PC Interface (433MHz)
Sorry, no products were found fitting that criteria. Please widen your search or reset item filters now