Our inventory consists of current and obsolete, new or reconditioned-tested relays. Protective relays are devices designed to trip a circuit breaker, within a thousandths of a second, when a fault is detected.
Schweitzer – SEL
The earlier designs were electromagnetic devices, relying on coils operating on moving parts to provide detection of abnormal operating conditions such as over current, reverse power flow, over-frequency and under-frequency.
Microprocessor based digital protection relays can replace the functions of electromechanical instruments. These relays convert voltage and currents to digital form and process with results measuring the usage of microprocessor. Digital relays can emulate functions of many electromechanical relays in one device. This allows for more simplified protection and maintenance.