A Clamp Meter is an Electrical Test Tool that Combines a Basic Digital Multi-Meter 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 other Conductor at any Point in an Electrical System, then Measure Current in that Circuit without Disconnecting /De Energizing it. Beneath their Plastic Moldings, Hard Jaws Consist of Ferrite Iron and are Engineered to Detect, Concentrate and Measure the Magnetic Field being Generated by Current . We have Consider This Type of Item Clamp-On TRMS Power Meter 3Phase / 1Phase TRMS.