Schweitzer Engineering Laboratories SEL-2505 2505131XX Remote IO Module

SEL-2505 Remote I/O Module from Schweitzer Engineering Laboratories expands protective-relay systems with eight input and eight output contacts linked over a fiber‑optic link to provide electrical isolation between the I/O ends. It accepts multiple power-supply configurations (12/24 VDC with a 9.6–36 VDC range; 48/125 VDC or 85–140 VAC; 85–264 VAC or 85–300 VDC, depending on variant) and draws up to 5 W. The unit includes a fiber port, a dedicated alarm contact for self-test and communications health, and a built‑in self‑test/communications monitor to help ensure reliable operation. Data transfer rates range from 9,600 to 38,400 bits per second with corresponding operation times, and the enclosure measures 338.6 mm high × 165.1 mm wide × 55.2 mm deep (13.33 in × 6.50 in × 2.175 in); it operates from −40 °C to +85 °C and is UL-listed. LEDs indicate input/output status and channel activity to aid quick diagnostics.