Abstract: A flexible conduit element that is made out of an annular corrugated tube or an annular corrugated pipe and is provided with a connection device. The connection device 6 is located on one end of the flexible conduit element and includes a joining piece 2 that has an external threading 5 and is placed on the end of the flexible conduit element 1. A union nut 3 can be shoved onto the flexible conduit element 1 and screwed onto the outer threading 5 of the joining piece 2, and a clamping ring 4 that can be shoved onto the flexible conduit element 1, is arranged between and deformed by the joining piece 2 and the union nut 3.

Abstract: In a brushless synchronous generator with an exciter, in which the three phase armature winding of the generator is coupled through a series regulator to the field winding of the exciter, and in which the rotating armature of the exciter feeds the rotating field winding for the synchronous generator through rectifiers, the series regulator being coupled in series between the three phase windings of the generator and the field winding of the exciter and including a control element, and in which there is a bypass diode across the exciter field winding, in order to protect the control element, a protective device is disposed between the control element and the three phase winding and an overvoltage arrester is placed in parallel across the exciter field winding and the bypass diode, the overvoltage arrester operating if an overvoltage occurs, thereby causing increased current to be drawn to actuate the protective device in series with the control element thereby preventing the synchronous generator from reaching