SMPR Microprocessor Protection Relays
Saint Petersburg, Gruzovoy pr., 19 +7(812) 329 97 97 Ru En

SMPR Microprocessor Protection Relays

SMPR measurement and protection relay is designed for measuring the line current and earth current root mean square values, as well as for measuring the line current and phase current in normal conditions and when disturbances occur. The current and voltage signals are detected by current transformers and voltage transformers; after processing the data, protection functions are performed according to ANSI, IAC or IEC regulations. Besides, the device can signal about circuit breaker or disconnector status.


  • Primary and secondary protection for generation and distribution systems.
  • Protection of medium-voltage and low-voltage circuits and radial feeders.
  • Protection of transformers, electrical power transmission lines, motors and generators.
  • The relay allows opening of a disconnector within its power range, leaving the function of circuit de-energizing to fuses in case of short-circuit.