GB343507A - Improvements in or relating to line protector relays - Google Patents

Abstract

343,507. Induction relays ; protective cut-out systems. SIEMENS & HALSKE AKT.-GES., Siemensstadt, Berlin. Nov. 13, 1929, No. 34707. Convention date, Nov. 29, 1928. [Class 38 (v).] Relates to an induction - type distance relay, for electric protective purposes, of the type in which a unif ormly-moving contact k moves towards a counter-contact e carried by the induction disc B which under the control of current and voltage windings c, d, assumes a position in accordance with the resistance of the line. The induction disc is influenced by an additional current torque assisting that of the first current winding and obtained from a solenoid v carrying a current winding acting on a sickleshaped iron armature n. This additional torque compensates for the saturation of the iron (on which the ordinary winding is wound) with very heavy currents. In the arrangement shown, on overload the relay A allows its contacts a to close, thereby energizing the solenoid of the relay C which attracts its armature and by putting a tension on the spring m rotates the travelling contact k through the gear-wheels shown. The solenoid also closes contacts which complete the circuit of the voltage winding d of the distance relay, the induction disc of which under the action of the voltage winding and of the main and compensating current windings takes up a position correctly representing the resistance of the line. When the contact k reaches the contact e on the disc, the circuit-breakers are tripped. A protective circuit in which the relays described are associated with an energy-direction relay to ensure tripping only with a particular direction of energy is described, Fig. 2 (not shown).