Product Description:

The SF-A3.0042.030-04.050 is a synchronous servo motor produced by Bosch Rexroth Indramat for the SF Servo Motors series. Designed for closed-loop positioning and velocity tasks in industrial automation, it converts controlled electrical energy from the matched drive into mechanical shaft rotation with high repeatability. The unit integrates an absolute value encoder so controllers receive a unique position word after every power cycle, eliminating the need for homing and supporting precise axis referencing in machine tools, pick-and-place stations, and packaging lines.

Its power section is dimensioned for a DC bus of 670 V, allowing the drive to deliver rated torque without saturation. The electromagnetic design yields a torque constant of 1.6 Nm/A, meaning each ampere of phase current produces 1.6 newton-meters, which simplifies current-loop tuning. During start-up, the windings can draw up to 2.3 A of locked-rotor current, producing a stall torque of 3.7 Nm for overcoming static friction in coupled mechanics. Once running, the rotor reaches a rated speed of 3000 rpm, matching common 50 Hz transmission ratios. Dynamic response is aided by a rotor inertia of only 7 × 10⁻⁴ kg·m², enabling fast acceleration without excessive drive effort.

For emergency stops or vertical-axis holding, the integrated electromagnetic brake operates on a supply of 24 VDC. When engaged, it applies a static torque of 10.0 Nm, keeping the shaft locked even if the main power bus is de-energized. Mechanical coupling is through a keyed shaft measuring Ø19 × 40 mm, and the motor face employs a 100 mm square IEC flange so installation aligns directly with geared reducers or bearing blocks. Dual NTC sensors embedded in the stator windings report thermal status back to the drive, enabling derating or shutdown before insulation limits are reached and ensuring long-term reliability.