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How is electric current measured in amperes?

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The science behind static electricity — electricity Explanation of static electricity and its manifestations in everyday life.

Electric current is measured in amperes (A) using an instrument called an ammeter. An ammeter is designed to measure the flow of electric charge through a circuit, whether it is direct current or alternating current.1

The ampere itself represents the rate of flow of electricity, defined as one coulomb of charge passing a point per second. Because ammeters must measure a wide range of current values, they often utilize a shunt—a device placed in parallel with the meter mechanism—to divert the majority of the current, allowing the meter to measure high values accurately.231

Different types of ammeters operate on various physical principles:
* D’Arsonval-movement ammeters measure direct current via a coil in a magnetic field.1
* Electrodynamic ammeters use moving and fixed coils to measure both AC and DC.1
* Thermal (hot-wire) ammeters measure AC by detecting the expansion of a wire heated by the current.1
* Digital ammeters convert analog current into digital signals using internal circuits.1