The LiftMaster CPSIII-UN4 Sensor and Card Kit is a monitored photoelectric safety solution for commercial and industrial door operators. Designed to provide entrapment protection in compliance with UL 325, it projects an infrared beam across the door opening; if the beam is interrupted during closing, the operator will stop or reverse to help protect people, vehicles, and equipment. The kit pairs a LiftMaster monitored photo eye (UN4, NEMA 4 rated for demanding indoor/outdoor environments) with a CPSIII interface card, making it an ideal replacement or upgrade for operators that require a compatible monitored input. It’s commonly used on sectional overhead doors, rolling steel doors, and other commercial applications where reliable, weather-resistant protection is needed.
This kit is intended for use with select LiftMaster commercial operators that support CPSIII cards and monitored photo eyes; always confirm compatibility in the operator’s manual before purchase. Installation typically involves mounting the photo eye near the bottom of the door opening per UL 325 guidelines, wiring to the operator’s low-voltage accessory terminals (commonly 24VDC), and inserting the CPSIII card into the designated slot on the control board to enable monitored functionality. As with all monitored safety devices, do not mix non-monitored sensors on the same input, follow alignment procedures precisely, and test operation during commissioning. The NEMA 4 enclosure helps protect against dust and water, making the CPSIII-UN4 a dependable choice for harsh commercial environments and a straightforward path to a compliant, universal-style monitored photo eye setup on LiftMaster systems.
