A clamp meter is one kind of test equipment and it is also known as Tong Tester. This equipment is very simple to use and operate. The main function of this device is to measure a live conductor in the circuit without damage or power loss. By using this equipment, one can measure the high-value current without turning off the circuit while testing. The main drawback of this meter is, the long tester accuracy is significantly low. This article discusses an overview of what is a clamp meter, construction, and its working.