| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an electric current sensor stably detecting a minute current by a simple structure. SOLUTION: An electric current sensor 1 is provided with a magnetic impedance element 2 generating voltage in response to the strength of a magnetic field Hi generated around an excited electric wire D to be detected, a circuit unit 5 having a driving circuit for driving the magnetic impedance element 2, and a computing unit 9 finding an electric current value of the current passing through the electric wire D to be detected on the basis of the voltage generated in the magnetic impedance element 2. The magnetic impedance element 2 is held in a casing body part 11 made of non-magnetic material, and a magnetism shield 13 shielding a disturbing magnetic field is arranged in the outer circumference of the casing body part 11. As the magnetic field Hi is detected by the highly sensitive magnetic impedance element 2, an electric current flowing through the electric wire D to be detected can be stably detected.</p> |
