M500 Electronic Megohmmeter, Insulation Tester, 0 to 1000 Megohms, for HVAC, Refrigerator Compressors, Motors, Portable Appliances, Relay Circuits, with Soft Carrying Case, Black

As a technician, having a dependable megohmmeter is a must — and this one delivers. Right out of the box, the build feels solid, with a rugged, rubberized housing that gives confidence it can handle the field. I’ve used it for testing motors, compressors, and insulation on wiring, and the readings are consistent and accurate every time. The display is bright and easy to read, even outdoors. I also appreciate the auto-discharge feature after testing — a safety must. The leads are quality too, with strong alligator clips that hold securely during testing.

This tool allowed me to troubleshoot and repair my air conditioner and saved me a lot of time and money.

One of the easiest, and quickest ways to test a compressor and insulation on the windings

I bought this Supco M500 tester to validate the motor on our sander. I was blown away by the portability, compactness, and the magnets on the ends of the leads. I also bought a competing unit with higher voltage and a display to tell me actual values, but I am very conflicted because the thought that went into this Supco unit is so great. In terms of a unit that is quick, easy to use, this Supco device wins, hands down. I could see the shorter leads being an issue eventually, but they're that short because they fold up in the back of the unit. I can't stress enough how convenient the magnets on the end of the aligator clips are. I can pop them onto screw terminals and very quickly test through a bunch of circuits without having to hold my fingers in the danger zone or question whether I slipped and caused an incorrect reading.

Excellent value for money. I work in commercial industrial A/C and megging out motors is something I do on a regular basis. This thing is fairly accurate, I've tested it alongside a $1500 AEMC unit and it worked just fine. I wouldn't recommend it on stuff much bigger than 25hp. It's simply not precise enough to keep a trending log. However for small compressors, blower motors, etc, it works great. It's also good for testing wiring inside units for those "intermittent" electrical issues we love to run across. Downside, the leads are far too short.

This item mega OHM meter is what I needed for diagnosing mini split system systems… it is required for testing the windings of a mini split compressor

Great value and fits in my toolbag. I use it often checking compressors and motors.

I thought that I would use this a lot. I don’t use it a lot. I don’t use. It is bad if it’s your motor could put power to it don’t move is definitely bad or maybe you have a bad capacitor. If you have a meter and you know how to use it same thing it is a nice tool though