Sensor infrarrojo de seguridad de 24 V CC, haz de fotocélula para sistema de acceso de abrelatas de compuerta de CA o CC (transmisor y receptor)

April 26, 2025. The Gatexpert Safety Infrared Photo Sensor is an excellent product! The Sensor includes both an infrared (IR) transmitter and an infrared (IR) receiver. They pass an IR beam from the transmitter to the receiver and respond to the interruption of that beam by an intervening object. Both the transmitter and the receiver accept supplied power of 12-28VAC or 12-33VDC, so the Sensor is flexible as to the choice of power source. The Sensor transmitter has a red LED indicator that is illuminated when the transmitter is receiving power. The Sensor receiver has a red LED indicator that: (1) is illuminated when the receiver is receiving power BUT NOT receiving the IR beam from the transmitter; and (2) is NOT illuminated when the receiver is NOT receiving power; or when the receiver is receiving power BUT ALSO is receiving the IR beam from the transmitter. Thus, this single red LED on the receiver is sufficient both to verify that power has been successfully applied to the receiver and to verify that the IR beam from the transmitter is properly aligned. To aid in achieving alignment, the transmitter and the receiver circuit boards are mounted on pivots that enable small angles of adjustment in a single plane (by less than the +-90 degrees indicated, but still entirely sufficient). Because the angle adjustment is accomplished by rotating the circuit boards themselves in pivots, and not by adjusting the position of the actual IR source element and the actual IR receiving element relative to the circuit boards, no stress is experienced by the connections between the elements and the boards by the adjustment process.The output of the Gatexpert Sensor is a single-pole double-throw (SPDT) electromechanical relay which electrically isolates whatever is connected to that relay from the Gatexpert’s own circuitry, increasing the variety of applications that can be supported. Thus, the relay is more desirable than an NPN or PNP transistor output, or an SCR output, as they do not provide such isolation. A jumper next to the relay permits selecting either the normally closed, or the normally open, contacts on the relay for external access.I used the Gatexpert Sensor to prevent my garage-door opener from lowering the garage door onto the open rear gate of an SUV which rises to nearly 7 feet above the floor and extends outside the garage door. The Gatexpert Sensor interacts with the garage door opener’s own photo protection system that is designed to prevent the door from being lowered onto an object or person that interrupts its own photo beam which is located about one foot above the floor. Here is how this works: When the rear gate is up, the gate blocks the Gatexpert Sensor’s IR beam, causing the Sensor to open its output relay. That open relay cuts the power to the garage door opener’s own photo transmitter, causing the opener’s own photo receiver to prevent the door from lowering, as if its own beam had been blocked. When the SUV’s gate is down, the Gatexpert Sensor’s IR beam completes the path to its own receiver and the output relay is closed. That allows the garage door’s own photo protection system to operate as intended to detect objects closer to the floor. This basic approach was suggested by an online discussion of protecting open rear gates in garages with garage-door openers. The Gatexpert Sensor is an excellent way of implementing this approach.One minor drawback merits note, but does not detract significantly from this favorable review. The mounting screws provided with the Gatexpert Sensor are too large in diameter to fit through the mounting holes in the plastic frames of the transmitter and the receiver. Perhaps screws of a smaller diameter, and the plastic inserts for receiving them, could be provided in the future. My solution was to use a drill bit, by hand, to ream the holes in the soft plastic out slightly, and gently, to allow my owns screws to be used.