A Solid-State Protective Relay for Use in Educational Laboratories

This paper presents the design and operation of a solid-state, directional, inverse-time overcurrent protective relay. One of the unique features of this relay is the ease of adaptability to various situations because of the variety and ranges of setting. This feature, and the very low cost of manufacturing the relay, make it ideal for use in a laboratory setup for educational purposes, as in a university, although its use is certainly not limited to such an application.