Fiber optic technologies have strong potential to augment and improve existing areas of sensor performance across many applications. Magnetic sensing, in particular, has attracted significant interest in structural health monitoring and ferromagnetic object detection. However, current technologies. Fiber optic current sensors (FOCSs), also called optical current transducers (OCTs), have inherent advantages over current transformers, including the following: Smaller size and weight. These advantages are becoming more significant. The Faraday effect (FE) is one of the principles OCT operation.