Autonics Co., Ltd. BM3M-TDT1,2 Photoelectric Sensor

BM3M-TDT1,2 from Autonics is a general-purpose through-beam photoelectric sensor pair with an integrated receiver amplifier. It uses a 940 nm infrared emitter and detects targets at up to 3 m, with reliable operation requiring alignment between emitter and receiver. The receiver side operates from 12–24 V DC and provides an NPN open-collector output in Dark On mode, so the output activates when the beam is interrupted. Wiring is three-wire: brown is +V, blue is 0V, and black is the load/output, with a maximum load current of 100 mA. The device supports an operating temperature range from –10 °C to 60 °C. The 3 m sensing distance is specified as 118.110 inches, reflecting the common metric/inch specification. The BM3M family features a compact, lightweight housing designed for tight automation spaces, typical of Autonics' BM line. Because this is a through-beam configuration, correct emitter–receiver alignment at the 3 m range is essential for consistent sensing performance.