Abstract: An electronically controlled pipe fracture safety device for operating devices which are fed by a hydraulic pump and which are actuated by a control slide value by means of hydraulic cylinders. Control lines branch off from lines which lead from the hydraulic pump via a control slide valve to the hydraulic cylinders, the control lines feeding the hydraulic medium to a differential flow monitor, on the piston of which a permanent magnet is fastened. The latter, by means of a reed contact as a result of a pressure difference existing between the control lines, which pressure difference is brought about by damage or fracture of a line, produces a signal in the NOR gate, the latter forming the input of a scoring logic. This signal retransmits a self-holding signal to NAND-gates which form a flip-flop. The self-holding signal causes deenergization of a relay and consequently an interruption of the current flow to the control slide valve and brings about the locking position of the latter.