Westinghouse Electric MDR-4103-1 Rotary Timing Relay

The Westinghouse MDR-4103-1 Rotary Timing Relay is an electromechanical rotary relay designed for precise timing, sequencing, and control circuit switching in industrial equipment, featuring a 118 VAC coil and 50/60 Hz operation. Its panel-mount design uses screw terminal connections and a multi-contact relay configuration to support sequential switching and control logic, aligning with timing and control circuit switching needs in industrial automation systems, motor control panels, and process control machinery. The MDR-4103-1 is industrial-duty rated and compatible with industrial control cabinets and panels, suitable for manufacturing facilities, HVAC equipment, and power distribution or motor control applications where reliable timing control and sequential operation are essential. Common replacements include Allen-Bradley 700-P Relay Series, Eaton D26MR Series Relay, and Square D 8501 Series Relay. Its feature set—panel mounting, screw terminals, 118 VAC coil, 50/60 Hz operation, industrial-duty rating, and multi-contact sequential switching—supports upgrading legacy timing and relay control circuits in industrial settings.