Product Description:

The 21BRCX-520-A7B/10 is a resolver produced by Danaher in the Dynapar Resolvers series. Acting as an electromechanical angle sensor, it converts shaft position into sine and cosine voltages that drives use for precise motor commutation and position feedback in industrial automation. The unit places the primary winding on the rotor, which helps keep the stator compact and simplifies excitation routing. Because no servo groove is machined into the case, the device mates directly to motor endbells with a clamp ring or light press fit when extra anti-rotation features are unnecessary.

The resolver body has an outside diameter of 2.1 in, a dimension that matches many small-frame servo motors and helps maintain a uniform air gap. Its shell is formed from steel, providing magnetic shielding and mechanical rigidity against clamping loads. A housing length of 1.25 in limits the required axial space, allowing the feedback element to fit behind bearing stacks without significantly extending the motor. Four leads exit the case, and each conductor is sized at 24 AWG, making the wiring suitable for low-current excitation and sense signals while preserving flexibility for tight cable runs. Electrical precision is maintained with a peak-to-peak error of 10 arc-min, supporting fine interpolation by digital converters in high-resolution drive systems.

The attached wiring provides a service loop of 12 in, allowing the leads to reach shield terminations without additional joints. The rotor contains a 0.50 in bore that fits common half-inch shafts, while its active stack supplies the magnetic coupling required by the stator coils. Electrical phasing is designated CCW, so the sine channel leads the cosine channel by 90 degrees during counterclockwise rotation to match standard drive conventions. The resolver has an overall mass of 8.8 oz, which limits the additional weight placed on lightweight servomotor assemblies and their supporting structures.