Sisco Relay Testers provide 3 phase relay testers and 6 phase relay testers. They are used to test the operation of protective relays, which are critical components in power systems. The purpose of a protective relay is to detect abnormal operating conditions in a power system, such as overcurrent, overvoltage, or underfrequency, and to initiate appropriate corrective actions to prevent damage to equipment and ensure the safety of personnel. Sisco relay tester with microcomputer control is used to simulate different operating conditions in a power system and to verify that the protective relays are operating correctly. The tester typically generates electrical signals that simulate fault conditions and measures the response of the protective relay to these signals. Protection relay testers are used by power system engineers, technicians, and maintenance personnel to ensure the reliability and safety of power systems. They are also used during commissioning and acceptance testing of new power systems or after modifications to existing systems.