NOVELTY - The converter has a three-way gearbox i.e. planetary gearbox, mounted in a transmission path between a driveshaft portion, an electric generator (21) and an energy accumulation device. The energy accumulation device comprises three gearbox shafts, where the gearbox shafts are arranged at opposite sides of the three-way gearbox. Couplings (67) of the gearbox shafts are arranged such that the three-way gearbox and the electric generator are located in stationary, sealed and closed space. The three-way gearbox and the electric generator are located at a radial distance of the driveshaft portion.    USE - Wave energy converter for producing electric energy from movements of water waves.    ADVANTAGE - The planetary gearbox is not located inside a counterweight drum which is not provided with delicate components mounted in interior such that the drum is firmly attached to anchor and counterweight shafts, respectively, and hence decreasing amount of special sealing and bearings needed. The converter provides transmission stage which is a belt or chain drive or gear drive, thus reducing torque on transmission components which significantly reduces weight and size of the components. The driveshaft is reduced in length and split up in shorter pieces, and bearing points needed for each shaft portion is reduced, thus reducing weight and cost. The converter provides easy solution to assemble, transport and service. The converter is provided with mechanical return feeding whose electric power needed to return feed to an anchor drum is reduced, thus reducing electrical losses in a system. The converter avoids risk of entanglement during standby due to slack in anchor line, and prevents the anchor line moving from a slack to a tensioned state such that avoiding sudden loads. The converter is provided with a wire shifting mechanism which allows smaller drums and lines or wires having smaller diameters to be used without limiting life of lines or wires, thus reducing input torque in the system.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a system for producing electric energy comprising a winding drum.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of transmission housing for a wave energy converter.    Electric generator (21)    Gearbox assembly (41)    Support housing (43)    Braking or locking mechanism (49)    Couplings (67)