ESA Certified Alarm Technician Practice Exam

Which meter is commonly used to measure current?

1. VOM Meter

2. Thermometer

3. Decibel Meter

4. Clamp Meter

The correct answer is: Clamp Meter

The clamp meter is specifically designed for measuring electrical current, particularly in conductors without needing to make direct contact with the circuit itself. This is achieved through the clamp mechanism that can encircle a wire, allowing the meter to utilize the magnetic field produced by the current flowing through the conductor to measure the amount of current accurately. This method is not only safe but also convenient, as it eliminates the need to interrupt the circuit. While the VOM (Volt-Ohm Meter) can measure current, it typically requires the circuit to be interrupted, making it less efficient for certain applications compared to a clamp meter. A thermometer is used for measuring temperature and is not applicable for measuring electrical current whatsoever. Similarly, a decibel meter is designed to gauge sound intensity and has no relevance in measuring electrical parameters. Therefore, in the context of measuring current, the clamp meter is the most appropriate and effective tool.