A device for detecting partial discharge in an electric cable, the device comprising: an electromagnetic radiation source configured for generating primary electromagnetic radiation to be coupled into at least one fiber at least a part of which being aligned along and motionally, in particular vibrationally, coupled with the electric cable; an electromagnetic radiation detector configured for detecting secondary electromagnetic radiation generated in the at least one fiber in response to the coupling of the primary electromagnetic radiation into the at least one fiber and being influenced by partial discharge induced local motion, in particular vibrations, of the electric cable, which local motions, in particular vibrations, couple to the at least one fiber; a partial discharge determining unit configured for determining information indicative of the partial discharge in the electric cable based on an analysis of the motionally, in particular vibrationally, influenced secondary electromagnetic radiation detected by the electromagnetic radiation detector, a shielding provision for shielding the at least one optical fiber so as to disable electromagnetic radiation generated in the electric cable by partial discharge from propagating into the at least one optical fiber; wherein the partial discharge determining unit is configured for determining the information indicative of the partial discharge exclusively considering the influence of the partial discharge induced local motions regardless of electromagnetic radiation generated in the electric cable by the partial discharge, which electromagnetic radiation is shielded by the shielding provision. an electromagnetic radiation source configured for generating primary electromagnetic radiation to be coupled into at least one fiber at least a part of which being aligned along and motionally, in particular vibrationally, coupled with the electric cable; an electromagnetic radiation detector configured for detecting secondary electromagnetic radiation generated in the at least one fiber in response to the coupling of the primary electromagnetic radiation into the at least one fiber and being influenced by partial discharge induced local motion, in particular vibrations, of the electric cable, which local motions, in particular vibrations, couple to the at least one fiber; a partial discharge determining unit configured for determining information indicative of the partial discharge in the electric cable based on an analysis of the motionally, in particular vibrationally, influenced secondary electromagnetic radiation detected by the electromagnetic radiation detector, a shielding provision for shielding the at least one optical fiber so as to disable electromagnetic radiation generated in the electric cable by partial discharge from propagating into the at least one optical fiber; wherein the partial discharge determining unit is configured for determining the information indicative of the partial discharge exclusively considering the influence of the partial discharge induced local motions regardless of electromagnetic radiation generated in the electric cable by the partial discharge, which electromagnetic radiation is shielded by the shielding provision.