A clamp meter is an electrical test tool that combines a basic digital multimeter with a current sensor. Clamps measure current. Probes measure voltage. Having a hinged jaw integrated into an electrical meter allows technicians to clamp the jaws around a wire, cable or another conductor at any point in an electrical system, then measure current in that circuit without disconnecting/de-energizing it.
Hi…a hall-effect clamp probe is very useful if you do anything with high current DC loads such as electric-hydraulic power packs, electric vehicles, etc. It is somewhat less important for low current DC loads where the typical multimeter’s 10A current shunt works fine. I have a hall-effect clamp good for 2,000A that I use with my Fluke 87, but I love the little HF clamp for general use and plan to pickup a couple spares