Banner Engineering SM502A Photoelectric Sensor

The Banner SM502A Photoelectric Sensor is a rugged DC retroreflective sensor with a visible red beam designed for fast, repeatable object detection in harsh industrial environments. Housed in a die-cast metal enclosure with a fully gasketed lens, the SM502A operates on 12–18 V DC and provides complementary open-collector outputs—one normally open and one normally closed—each capable of sinking up to 250 mA, with short-circuit protection and reverse-polarity protection. A rear red indicator LED lights when the sensor detects light, and sensitivity is adjustable via a single-turn side screw, while a 6-foot, 4-conductor shielded cable supports reliable wiring in rugged factories. Range is defined by model-specific excess gain curves, so performance depends on reflector type and installation geometry; this model is intended for retroreflective sensing, not as a personnel-safety device. Operating temperature is -40 to +70 C, and the unit features the robust construction and gasketed lens assemblies characteristic of Banner’s retroreflective sensors, with multiple enclosure options and careful protection against miswiring and environmental exposure.