Product Description:

The HS35R0900M37J is a hollow-shaft rotary encoder manufactured by Danaher for the Dynapar Encoders series. Designed for motion feedback in industrial automation, it mounts directly on a motor or drive shaft and converts mechanical rotation into two square-wave channels that a controller can count to determine position and speed. Its hollow-shaft design supports a compact installation while eliminating the need for a separate shaft coupling.

The unit supports a resolution of 900 PPR, allowing controllers to detect 900 pulses during one mechanical revolution for precise speed regulation. The output electronics track edge changes up to 100 kHz, so signal integrity is preserved even at the maximum shaft speed of 3600 rpm. Quadrature outputs leave the sensor 90° ±22.5° electrical apart, while duty-cycle symmetry is held to 180° ±18° to minimize timing error. The sealed housing meets the NEMA 4/IP66 rating, protecting the internal optics against powerful water jets and airborne contaminants. A bore tolerance of +0.0003/+0.0005 inches provides a slip fit on standard motor shafts. The rotor withstands an axial end thrust of 30 lb without degrading accuracy.

A radial load of up to 40 lb can be applied to the hollow shaft, enabling direct installation on shafts exposed to belt tension without auxiliary bearings. Drive power demand stays low because running friction is limited to 4.5 oz-in, allowing the encoder to follow changes in shaft speed with minimal resistance. Startup torque is limited to 5.0 oz-in, reducing the initial load placed on the connected shaft as rotation begins. The encoder weighs 16 oz, which limits the additional mass attached to high-speed rotating equipment. Its direct mounting arrangement also reduces the number of mechanical interfaces that could introduce alignment errors or backlash. The sealed enclosure and controlled bearing loads support operation on conveyors, mixers, motors, and other rotating industrial machinery.