Electrical power jack for detachable connection with an electrical power plug and electrical power coupling consisting of such a power jack and an associated electrical power plug

An electrical power coupling (50) comprising an electrical power jack (1) and an associated electrical power plug (30) with an essentially cylindrical pin (31), the electrical power jack (1) being designed for detachable connection to the electrical power plug (30), with a base body (2) made of electrically conductive material with a bore (2′) for accommodating the essentially cylindrical pin (31) of the electrical power plug (30) and with a device (4) for connection to a power cable (40), wherein a helical groove (5) for insertion of a locking nose (32) of the electrical power plug (30) is arranged in the base body (2), the base body (2) comprising a bushing (3) with the helical groove (5) and a receptacle (3′) for the bushing (3), wherein the helical groove (5) of the base body (2) of the electrical power jack (1) comprises at least two areas (a, c) with a positive gradient, and at the end of each area (a, c) with a positive gradient areas (b, d) with a negative gradient are arranged to form a respective latching step, wherein the receptacle (3′) is formed from metal or a metal alloy with an enclosure (13) of electrically insulating material and the bushing (3) is formed from a harder material than the receptacle (3′) and than the cylindrical pin (31) of the electrical power plug (30).