Uploaded July 2026 | Updated September 2026, 3 weeks ago

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This video explains what electrical insulation testing is, why it’s important, and how insulation resistance is measured using megohmmeters or “meggers”.

Test and Measurement Fundamentals Playlist: youtube.com/playlist?list=PLKxVoO5jUTlvsVtDcqrVn0ybqBVlLj2z8

Power analyzers from Rohde & Schwarz: rohde-schwarz.com/us/products/test-and-measurement/power-analyzers_254849.html

Timeline:
00:00 Introduction
00:16 About resistance measurements
01:10 About insulation
02:12 About insulation resistance testing
03:16 Using an insulation tester / megohmmeter
04:25 Aside: a brief word about safety
05:06 Selecting a voltage
05:56 Common applications of insulation resistance testing
06:22 Example: testing heating elements
07:06 Example: testing cables
07:50 Example: testing three phase motors
08:51 Insulation resistance as a function of time
09:47 About polarization index and dielectric absorption ratio
11:10 Summary