Product Description:

The SF-A3.0042.030-04.015 is a brushless AC servo motor built by Bosch Rexroth Indramat for the SF Servo Motors series. It operates as the rotary actuator in closed-loop drive systems, translating command currents from a servo controller into proportional shaft torque and position. In assembly stations, packaging equipment, or pick-and-place cells, the unit supplies repeatable speed and precision for axes that demand rapid acceleration and stopping accuracy. Its brushless design reduces routine wear at the motor itself because commutation is handled electronically by the connected servo drive.

At its rated operating point, the shaft turns at 3000 rpm, and feedback helps maintain constant output under load. The electromagnetic design yields a torque constant of 1.6 Nm/A, so the controller can relate torque directly to phase current. When the rotor is locked, the motor can withstand a static load of 3.7 Nm while drawing 2.3 A, which helps with drive sizing during startup. A spring-applied holding brake secures the axis with 10.0 Nm of torque once power is removed. The brake’s rotating mass contributes only 1.06 × 10⁻⁴ kg·m² of inertia, minimizing impact on servo response. Plug braking circuitry is matched to a 5.6 Ω resistor and can absorb 261 Ws of energy during emergency stops. The housing tolerates shocks up to 6 g without mechanical damage.

The brake is powered from a 24 VDC supply and releases when a coil current of 0.66 A is applied. Engagement completes within 20 ms, and full mechanical clearance is reached after 29 ms, allowing the controller to coordinate clamp timing with axis motion. Acoustic emissions are limited to 58 dB(A), which helps keep machine noise within typical industrial levels. Because the electromagnetic coil is energized only during disengagement, the brake introduces minimal heat into neighboring windings, supporting continuous duty cycles on densely packed multi-axis assemblies. Fast brake response also helps the axis transition from motion to secure holding without a long coast period after a stop command.