Allen-Bradley 845D-SJDN14BDCN4 Optical Absolute Encoder

The Allen-Bradley 845D-SJDN14BDCN4 Optical Absolute Encoder is a single-turn, 25 mm size optical absolute encoder from the 845D family, designed for precise, non-volatile position feedback in industrial automation and motion-control applications. It provides a binary output across an 8–12 bit resolution range, enabling digital position information to be read by PLCs and motion controllers. The unit is housed in a NEMA Type 4 enclosure, offering protection suitable for harsh factory environments. As part of Rockwell Automation’s 845D line of absolute optical encoders, this model shares the family’s emphasis on robust construction and reliable absolute feedback, with variations within the lineup that support different output formats while maintaining core sensing technology and rugged enclosure.