Parameters Rated Control Supply Voltage: 208 – 440 V AC across phases (measuring voltage equals control supply). Voltage Measuring Range: Three‑phase line‑to‑line input 208 – 440 V AC. Rated Frequency: 50/60 Hz operation. Output Contact Configuration: 1 changeover (SPDT) contact. Contact Rating: Typically suitable for control duty, e.g., switching up to ~250 V AC at moderate current levels (pilot duty load). Control Logic: Closed circuit principle — contact changes state when monitored conditions are met/failed. Delays: Brief built‑in start‑up and trip delays (~500 ms) to prevent nuisance tripping during normal power fluctuations. Mechanical & Environmental Mounting Footprint: Slim module (approx. ~22.5 mm width) for panel or DIN‑rail mounted sockets; installs alongside other control devices. Operating Ambient: Designed for typical electrical cabinet/panel environments. Terminal Interface: Screw clamp terminals for power and load wiring. Mechanical Durability: Rated for long service life in industrial control applications. Function Summary The CM‑PFE monitors the presence, order, and continuity of all three phases in an AC supply. If phase sequence is wrong or any phase is lost, the relay detects the fault and changes the state of its output contact. This output can then be used to disconnect equipment, trigger alarms, inhibit starts, or inform control logic to prevent damage. Typical Applications Motor protection circuits to prevent incorrect rotation due to wrong phase sequence. Control panels where phase integrity is required before allowing operation of heavy loads. Industrial automation systems requiring reliable phase monitoring. Distribution systems to detect and respond to phase loss or incorrect phase sequence.