EMX IRB-325 Infrared Photoeye Sensor

The EMX IRB-325 is a UL 325-2018-compliant infrared thru-beam photoeye with a 6-65-foot detection range, 12-24 VAC/VDC operation, and monitored normally closed (NC) compatibility. Designed for automatic gates, garage doors, and commercial door operators, it uses separate transmitter and receiver units to detect obstructions and signal compatible operator safety inputs. The sensor features a NEMA 4X weather-resistant enclosure, three-position receiver sensitivity adjustment, Form C relay contacts rated at 1 amp at 30 VDC, and diagnostic LED indicators for alignment and obstruction detection.

EMX IRB-325 UL 325 Monitored Infrared Thru-Beam Gate Safety Photoeye

The EMX IRB-325 is a UL 325-2018-compliant infrared thru-beam photoelectric sensor designed for external entrapment protection on automatic gates and doors. Manufactured by EMX Industries, the IRB-325 uses a separate infrared transmitter (TX) and receiver (RX) to establish an invisible detection beam across a gate opening, driveway, garage entrance, or controlled access lane. When a person, vehicle, or other obstruction interrupts the beam, the receiver changes its relay output to notify the connected operator. The sensor provides a manufacturer-specified operating range of 6 to 65 feet (1.8 to 19.8 meters), supporting pedestrian gate openings and wider commercial vehicle entrances. Classified as a Type B1 non-contact entrapment protection device, the IRB-325 is intended for automatic operators that support its normally closed monitoring method. Its NEMA 4X-rated construction and rugged outdoor design make it suitable for commercial gates, residential driveways, parking barriers, industrial entrances, and compatible overhead door applications.

The IRB-325 incorporates adjustable infrared detection sensitivity with high, medium, and low receiver settings to support proper alignment and obstruction detection across different installation distances. Two internal sensitivity jumpers allow installers to configure receiver gain, helping maintain reliable beam detection while limiting unwanted activation caused by nearby reflective surfaces. The sensor uses a lens-free optical design that simplifies transmitter-to-receiver alignment and reduces problems associated with lens fogging. The receiver includes two red detection LEDs and a green power LED, while the transmitter includes its own power indicator. During normal operation with proper alignment and an unobstructed beam, both red receiver indicators remain off. An interrupted beam causes both red indicators to illuminate, while a single illuminated red indicator can signal imperfect alignment. These diagnostic features allow technicians to verify transmitter positioning, receiver sensitivity, and obstruction response during installation and maintenance.

The EMX IRB-325 operates from a 12-24 VAC or VDC low-voltage power source, with separate power connections provided for the transmitter and receiver. The manufacturer's installation manual identifies a maximum operating current of 150 mA with the relay activated, while its technical datasheet specifies individual transmitter and receiver current requirements. At 12 VDC, the receiver draws approximately 33 mA in standby and 25 mA during detection; at 24 VAC/VDC, receiver consumption is approximately 56 mA in standby and 38 mA during detection. Transmitter current is specified at approximately 47 mA. The receiver incorporates a Form C single-pole double-throw relay with normally open (NO), normally closed (NC), and common (COM) contacts, rated at 1 amp at 30 VDC. For compatible UL 325 monitored installations, the normally closed contact and common terminals are connected to the operator's designated monitored safety input. An internal thermal fuse provides surge-related protection, while the non-polarized power input terminals simplify low-voltage AC or DC wiring.

The IRB-325 features a NEMA 4X weather-resistant enclosure measuring 5.03 inches high, 3.06 inches wide, and 3.02 inches deep (128 x 78 x 77 mm). Its housing carries applicable UL and CSA enclosure classifications including Types 4, 4X, 3, 3R, 12, and 13. The rugged enclosure protects the internal electronics from outdoor environmental exposure when properly assembled and sealed. The photoeye operates across a temperature range of -40 F to 170 F (-40 C to 77 C), accommodating cold-weather gate installations and hot industrial environments. Both transmitter and receiver use removable covers secured by four screws, with terminal connections located inside the housing. For wet-location installations, EMX requires UL-listed watertight strain relief fittings or appropriate watertight conduit connectors to preserve the enclosure's environmental protection. Optional accessories include the IRB-325-HD set of two gray powder-coated steel protective hoods, the IRB-325-SP liquid-tight strain relief connector set, and the IRB-325-PT black powder-coated steel mounting post. The protective hoods help reduce exposure to weather and accidental mechanical contact from vehicles or surrounding equipment.

The EMX IRB-325 is designed for monitored non-contact entrapment protection in automatic gate and door systems requiring normally closed safety sensor monitoring. The manufacturer identifies the IRB-325 as UL 325-2018 compliant when used with compatible operators that support NC monitoring. The receiver's relay changes state when the beam is interrupted, allowing the connected operator to initiate the appropriate stop, reverse, or safety response according to its configuration and applicable requirements. Installation requires proper positioning of the transmitter and receiver, verification of unobstructed beam alignment, and functional testing with obstructions at several points along the detection path. The IRB-325 differs from the EMX IRB-4X2, which is a non-monitored photoeye with a 115-foot range, and the IRB-MON2, which supports additional monitored interface methods and extended detection distances. The IRB-325 is available as a transmitter and receiver set, with a separate IRB-325 KIT configuration that includes two protective hoods. EMX provides a two-year limited manufacturer warranty against defects in materials and workmanship under normal use. Combining 65-foot infrared detection, NC monitoring compatibility, adjustable sensitivity, Form C relay switching, and NEMA 4X outdoor protection, the IRB-325 provides a photoelectric safety sensor solution for compatible automatic gate and door operators.