Skip to Main Content
  • Instrumart
Instrumart logo
  • Products
  • Brands
  • Applications
  • Lab
  • Blog
  • Account
  • Email Us
  • 1-800-884-4967
  • What can we help you find?

    Can’t find what you’re looking for? Contact one of our engineers today. We’re open Mo-Th 8am to 5:30pm. Fr 8am to 5pm ET.
    • 1-800-884-4967
    • Email Us
    • Live Chat
  1. Insulation Testers

Extech MG300 / MG302 CatIV Insulation Tester / Multimeter

Combines a 1000V Insulation Tester With a full-featured True RMS MultiMeter.

Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
  • Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
    Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
  • Extech MG300 Wireless Insulation Tester & Multimeter Product Video
    Extech MG300 Wireless Insulation Tester & Multimeter Product Video
Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
Retired products cannot be ordered
The Extech MG325 Insulation Tester / True RMS MultiMeter is the recommended replacement.

View Company Reviewsby Trustpilot
Manufactured
  • By Extech
Includes
  • FREE Ground Shipping on orders of $1,000 or more
  • FREE Lifetime Tech Support
Questions?
Call 1-800-884-4967 or email sales@instrumart.com. Open Mo-Th 8am to 5:30pm. Fr 8am to 5pm ET.
Trustpilot

Overview

Features

  • Wireless USB interface transmits measurement data to a PC
  • Backlit super large triple display
  • 125V, 250V, 500V, and 1000V test voltages
  • Insulation Resistance from 0.001MΩ to 4000MΩ
  • Auto discharge of capacitive voltage
  • Lock Power On Function for hands-free operation
  • Data Hold to freeze displayed reading
  • Min/Max and Relative mode
  • Auto power off
  • Waterproof (IP67) rugged double-molded design

What's in the Box

  • Remote receiver with USB cable
  • Windows compatible software
  • Test leads with alligator clips
  • Type K bead wire temperature probe with adapter
  • Carrying case
  • Six AA batteries

Documents

Documents

  • Extech MG300 / MG302 CatIV Insulation Tester / Multimeter Datasheet PDF (486 KB)
  • All possible part numbers

Accessories

Current Clamps

FLIR TA72 / TA74 Current Probes
FLIR TA72 / TA74 Current Probes

Compatible with most brands of Multimeters and Clamp Meters, max AC current 3000A, ±3.0% accuracy.

Mfg. has some models in stock
Starting at $185.99

Accessories

Please consider these optional accessories.

Extech CA3000 Series Clamp-On Adapters
Extech CA3000 Series Clamp-On Adapters

CAT IV 3000A AC Flex Clamp-on Adaptors, 10" or 18", AC current up to 3000A, 7.5mm cable diameter.

Starting at $150.99

Need Help? Call a Temperature engineer at 1-800-884-4967

We're open Mo-Th 8am to 5:30pm. Fr 8am to 5pm ET

David S. headshot David S.
Applications Engineer
Alex A. headshot Alex A.
Senior Applications Engineer
19 years at Instrumart
Dwight M. headshot Dwight M.
Senior Applications Engineer
28 years at Instrumart
Rhys D. headshot Rhys D.
Applications Engineer
Ron J. headshot Ron J.
Temperature Engineering Lead
29 years at Instrumart
Luke M. headshot Luke M.
Applications Engineer
5 years at Instrumart
Shawn D. headshot Shawn D.
Senior Applications Engineer
20 years at Instrumart
David S. headshot David S.
Applications Engineer
Alex A. headshot Alex A.
Senior Applications Engineer
19 years at Instrumart
Dwight M. headshot Dwight M.
Senior Applications Engineer
28 years at Instrumart
Rhys D. headshot Rhys D.
Applications Engineer
Ron J. headshot Ron J.
Temperature Engineering Lead
29 years at Instrumart
Luke M. headshot Luke M.
Applications Engineer
5 years at Instrumart
Shawn D. headshot Shawn D.
Senior Applications Engineer
20 years at Instrumart
David S. headshot David S.
Applications Engineer

Recently Viewed

Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
Extech MG300 / MG302 CatIV Insulation Tester / Multimeter
United States Canada Mexico
Shop
Products
Brands
Applications
Support
Customer Service
Ask a Question
Live Chat
Track Order
Fraud Prevention
Financing
Our Company
Blog
About Us
Contact Us
Jobs
Travel Information
Our Team
Privacy Policy
Terms and Conditions of Sale
Accessibility Statement
Connect
1-800-884-4967
sales@instrumart.com
Instrumart
35 Green Mountain Dr
S Burlington, VT 05403 US
Mo-Th 8:00am to 5:30pm ET
Fr 8:00am to 5:00pm ET
Join Us on Facebook
Follow Us on X

Instrumart is a member of a family of industrial stores

Instrumart Compressor World Pump World BioPharm World Filtration World Motion World Qualitrol Engineered Solutions Wholesale Air Pipe
© Instrumart 2025

Family of Industrial Stores

Welcome to our family of stores, your go-to source for a wide selection of commercial and industrial products in the flow control and automation sectors. Each store features a curated range of specialized industrial solutions, with many items designed to complement each other, ensuring you can find everything you need for your specific application. Explore the stores below to discover our extensive product offerings for your business needs.

  • Instrumart

    Shop Industrial and Laboratory Instruments.

    Shop Now!
  • Compressor World

    Shop Compressed Air Equipment.

    Shop Now!
  • Pump World

    Shop Industrial, Water, and Waste Water Pumps.

    Shop Now!
  • BioPharm World

    Shop Sanitary Process Solutions and Products.

    Shop Now!
  • Filtration World

    Shop Industrial Filters.

    Shop Now!
  • Motion World

    Shop Motion Control and Process Automation Systems.

    Shop Now!
  • Qualitrol

    Shop Remanufactured or Repair Automation Products.

    Shop Now!
  • Engineered Solutions

    Shop Custom Engineered and Manufactured Systems.

    Shop Now!
  • Wholesale Air Pipe

    Shop Air Piping.

    Shop Now!