electrodynamic ammeter

instrument

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Last updated

June 26, 2026

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An electrodynamic ammeter is an instrument used to measure electric current, specifically in amperes. It operates on the principle of electromagnetic interaction between two coils. In this type of ammeter, a moving coil rotates within the magnetic field generated by a fixed coil, and this interaction produces a torque that is balanced by a spring.12

Electrodynamic ammeters can measure both direct current (DC) and alternating current (AC), though AC measurements typically require a rectifier to convert the current to DC. These instruments offer high accuracy, generally ranging from 0.1 to 0.25 percent.1

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ammeter
The electrodynamic ammeter uses a moving coil rotating in the field produced by a fixed coil. It measures direct and alternating current (by using a rectifier to convert the AC to DC) with accuracies of 0.1 to 0.25 percent. In the thermal (or hot-wire) ammeter, used…
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The electrodynamic ammeter uses a moving coil rotating in the field produced by a fixed coil. It measures direct and alternating current (by using a rectifier to convert the AC to DC) with accuracies of 0.1 to 0.25 percent. In the thermal (or hot-wire) ammeter, used…
Read More