Analysis of small intermediate relays from leading manufacturers

Abstract

This paper presents a comparative analysis of technical characteristics and designs of small intermediate relays from various manufacturers. The following main characteristics of relay are considered: operation and release values; weight and dimensions; power consumption; time parameters; reliability characteristics. The design of the relays of the Russian and international manufacturers are being discussed, their design features that affect the technical characteristics are considered. It is noted that the fastening of movable contacts directly to the armature (relays from Finder, Relpol, Irkutsk Relay Plant) requires a flexible connection with the relay contacts, which leads to more complicated assembly and calibration of relays. It is shown that the kinematic diagram in the presence of free travel with no mechanical coupling with the contact pusher, used in the relay from Schrack, can reduce power consumption and increase the vibration and shock resistance of the relay break contacts. In Schrack AC relays, the operating clearance zone is configured to create a short-circuited loop with reduced electrical resistance and to provide optimum conditions for reducing armature vibration. The appropriate relay designs in terms of improving technical characteristics are proposed. The advantage of a flat return spring over cylindrical coil springs in terms of manufacturing technology and stability of mechanical characteristics of relay is shown. It was revealed that the electromagnetic drive of the Schrack relay compares favorably with electromagnetic drives of other companies in terms of the use of stray magnetic fluxes to create a useful electromagnetic torque. Based on the results of the comparative analysis and experimental study of existing relay designs, recommendations were formulated for the development of a new series of the Russian small intermediate relays within the framework of the import substitution program.