Allen-Bradley 842HR-SJA3115FWY2 Absolute Encoder

Description

The Allen-Bradley 842HR-SJA3115FWY2 Encoder is a high-resolution single-turn sine/cosine absolute encoder designed to provide precise position, speed, and commutation feedback for high-performance servo drive systems. It features a 12 mm blind hollow shaft, hybrid sine/cosine and serial interface, and a 5–12 VDC supply, delivering high-accuracy motion feedback for demanding industrial automation and motion control applications. Commonly installed on servo motors, CNC machines, robotics, packaging equipment, machine tools, and automated production systems. Maintenance teams and system integrators use this encoder for OEM replacement, servo motor repair, retrofit projects, and precision motion control system upgrades.

Applications

The Allen-Bradley 842HR-SJA3115FWY2 is used in digital servo drive systems requiring both absolute position feedback and high-resolution incremental feedback from a single encoder. Typical applications include CNC machining centers, robotics, printing presses, packaging machinery, semiconductor equipment, and automated manufacturing systems. The encoder combines a 15-bit absolute position output with sine/cosine signals for speed regulation and commutation, making it compatible with Hiperface®-enabled servo systems and Rockwell Automation motion control products.

Technical Specifications

• Manufacturer: Allen-Bradley (Rockwell Automation)
• Part Number: 842HR-SJA3115FWY2
• Product Type: Sine/Cosine Absolute Encoder
• Series: Bulletin 842HR
• Encoder Type: Single-Turn Absolute Encoder
• Shaft Configuration: 12 mm Blind Hollow Shaft
• Supply Voltage: 5–12 VDC
• Output Interface: Sine/Cosine with RS-485 Serial (Hiperface® Compatible)
• Absolute Resolution: 15-bit (32,768 steps per revolution)
• Incremental Output: 1,024 Sine/Cosine Cycles per Revolution (up to approximately 2 million interpolated counts per revolution)
• Electrical Connection: MS 10-Pin Connector
• Mounting Style: Hub Shaft
• Application: High-Performance Servo Feedback and Motion Control
• Features: Absolute position feedback, high-resolution incremental output, commutation support, compact industrial design, and high-accuracy servo control.

Common Replacements

• Allen-Bradley 842HR-SJA3115FWYD
• Allen-Bradley 842HR-MJA3115FWY2
• Allen-Bradley 842HR-SJA6115FWY2