The LiftMaster CPS-EI Monitored 4‑Wire Sensing Edge Interface is a safety accessory that connects a standard 2‑wire door sensing edge to compatible LiftMaster commercial door operators that require a monitored, 4‑wire entrapment protection device. Designed for use on sectional, rolling steel, and other commercial/industrial doors, the CPS‑EI supervises the edge circuit so the operator can detect activations as well as wiring faults, supporting UL 325 entrapment protection requirements. It is an ideal replacement part or upgrade when moving to newer monitored operators, helping ensure a compliant, reliable safety edge solution for dock doors, warehouses, and high‑cycle facilities.
This interface is powered by the operator’s low‑voltage accessory output and provides a 4‑wire supervised connection at the operator while accepting a 2‑wire contact/resistive sensing edge at the door. When the edge is compressed or a fault is detected, the interface signals the operator to stop and/or reverse per the operator’s logic. Compatibility is intended for LiftMaster commercial door operators that support monitored 4‑wire edge inputs (such as many Logic 5.0 models); always verify support in the operator’s manual before installation. Typical setup involves mounting the module near the operator, landing the 4‑wire harness to the monitored edge terminals, connecting the two edge leads, and programming the operator to recognize a monitored edge. After wiring, perform required UL 325 safety checks and a full function test to confirm proper detection in both opening and closing directions.
