Simplex MR-101C AP C Relay For Fire Alarm Systems

MR-101/C/R Multi-Voltage Relay is a compact, single-relay module that provides a standard SPDT dry contact (C, NO, NC) in a 1‑module position, designed for track-mount or enclosed installations in fire alarm and building-control systems. It accepts four energizing voltages—24 VDC, 24 VAC, 120 VAC, or 230 VAC—with a typical coil current around 18 mA at 24 V, enabling flexible integration with various control circuits. The SPDT contact is rated up to 10 A resistive at 120 VAC, suitable for switching common building loads, while the rating is lower at higher voltages; status is indicated by an onboard LED when the coil is energized. The unit is UL-listed as a recognized component (File #S3403) and is available in track-mounted or enclosed formats, with dimensions of 3.25 inches high by 2.13 inches wide by 1.5 inches deep for the track-mount version. Coil connections often utilize 18 AWG color‑coded leads, supporting straightforward wiring to common fire-alarm interfaces. This MR‑series relay is commonly used to interlock HVAC, energy-management, lighting-control, and other building-system devices with fire alarm circuits, providing a dependable, configurable interface that can be driven from multiple voltage sources without multiple relays.