Protective relays -- demo unit (SEL-501 relay time overcurrent trip)

This project incorporates both electromechanical and solid-state overcurrent relays to trip two circuit breakers conveying 120 VAC power to common loads (e.g. vacuum cleaner, hair dryer, or anything else drawing substantial current). The purpose is to demonstrate the operation of protective relays, and to serve as a system we can routinely calibrate.