3-phase faraday optical current sensor assembly

摘要

The object of the invention is to provide a method and a system for fixating a Faraday optical current sensor (12a, 12b, 12c) in a suitable measurement position for measuring the current in a 3-phase cable (14). The 3-phase cable (14) comprises 3 individual section-shaped phase conductors (16a, 16b, 16c) insulated in relation to one another and encapsulated inside an insulator (18). The method comprises the provision of a Faraday optical current sensor arrangement comprising 3 Faraday optical current sensors (12a, 12b, 12c), each Faraday optical current sensor being fixated in a specific position outside the section-shaped phase conductors (16a, 16b, 16c), and the provision of a processing unit for calculating a current value from a magnetic field value. The method is performed by measuring 3 magnetic field values by using each of the 3 Faraday optical current sensors (12a, 12b, 12c) and calculating the current in each of the section-shaped phase conductors (16a, 16b, 16c) by using the processing unit and the 3 magnetic field values.