A winch comprises a cable roll; a cable having one end fixed to the cable roll and another end configured to electrically connect an electric device to the cable, wherein the cable is further configured to provide the electric device with electric power and/or with data; a framework to which the cable roll is mounted; measuring means connected to the framework and configured to provide data related to the length of an unwound part of the cable; and processing means configured to control winding and unwinding of the cable based on data provided by the measuring means. The cable has a predetermined reference state at which a predetermined fixed reference point is at a reference position in relation to a coordinate system, wherein the length of unwound cable is defined as the distance measured along the cable, between the location of the predetermined fixed reference point and the reference position.