The digital protective relay is a protective relay that uses a microprocessor to analyze power system voltages, currents or other process quantities
A big difference between conventional electromechanical and static relays is how the relays are wired. Electromechanical and static relays have fixed wiring and the setting is manual. Numeric relays, on the other hand, are programmable relays where the characteristics and behavior can be programmed. Most numerical relays are also multifunctional.