IEC 60255-149:2013 specifies minimum requirements for thermal protection relays. This standard includes specification of the protection function, measurement characteristics and test methodologies. Protective relays and devices have been developed over 100 years ago to provide “lastline”of defense for the electrical systems. They are intended to quickly identify a fault and isolate it so the balance of the system continue to run under normal conditions. The selection and applications of. There are different types of relays available in the market which are utilized depending on the application. Thermal relays are the perfect solution for. The operational mechanism of this thermal relay is based on a precisely calibrated bimetallic strip assembly. The content of the article: Why are protective devices necessary? Why are protective devices necessary? Even if the drive. A thermal relay is an electromechanical device that detects temperature changes in electrical circuits, protecting equipment from overload and overheating.
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