Fiber optic current sensors work by detecting changes in light as it interacts with a magnetic field created by an electrical current. These sensors rely on the Faraday Effect, which occurs when a magnetic field causes a rotation in the polarization of light passing through an. A fiber-optic sensor is a sensor that uses optical fiber either as the sensing element ("intrinsic sensors"), or as a means of relaying signals from a remote sensor to the electronics that process the signals ("extrinsic sensors"). Fibers have many uses in remote sensing. The Faraday effect (FE) is one of the principles OCT operation. Fiber optic current sensors are revolutionizing the way electrical currents are measured, providing high sensitivity, immunity to electromagnetic interference (EMI), and the ability to function in harsh environments. A sensor is a device that measures a physical quantity and converts it into a. Fiber-optic sensors (also called optical fiber sensors) are fiber -based optical sensors for some quantity, typically temperature or mechanical strain, but sometimes also displacements, vibrations, pressure, acceleration, rotations (measured with optical gyroscopes based on the Sagnac effect), or.