The 3-1618100-2 is a generator-to-generator paralleling relay from the 1800 series, designed to permit paralleling only when two generators are online, and their voltages are equal and in phase. It operates with a sensing voltage of 120V across a line frequency of 50-500 Hz, sensing both phase angle displacement and amplitude difference. The relay features an external pick-up adjustment for 10-30% of the nominal voltage and includes a fixed 60-millisecond time delay to ensure frequencies are sufficiently close before connection. This functionality is crucial for preventing damage and system disturbances in power generation applications.