Sooner or later though you will find yourself trying to fix a power supply or something. You will measure the inputs, and the parts on the board that should have the AC power. And some spike comes down the line from a higher voltage flashover 60 miles away, or lightening, and boom, you are hurt or dead.
I never used to think about that until I spoke to a few trained up power guys. You can get thousands of volts intermittently on a simple house supply. And cheap chinese meters explode! Even the ones supposedly safe 1000V standards. The chinese will add anything for more sales! Your fluke is safe until you add cheap leads.
https://dam-assets.fluke.com/s3fs-publi ... NG_B_W.PDFGet something like this, and avoid AC systems.
https://www.aliexpress.com/i/32841080994.html