Product Description:

The SF-A2.0020.030-14.037 is a permanently excited synchronous servo motor manufactured by Bosch Rexroth Indramat for the SF Servo Motors series. It converts controlled current from a digital drive into repeatable rotation for positioning axes, feed drives, and indexing tables used in automated production. The unit suits compact installations that call for quick response, stable servo behavior, and high positional accuracy.

Its rated speed reaches 3000 rpm, allowing direct coupling to machinery that demands moderate rotational frequencies without additional gearing. A torque constant of 1.5 Nm/A links phase current to developed torque, enabling the drive amplifier to estimate motor output from measured current. The stator is wound for a DC link of 670 V, so the motor can be operated from high-voltage inverters typically used in multi-axis systems. Heat is removed through natural convection, so no auxiliary fan or liquid circuit is required. For controlled stopping, the unit uses a fail-safe permanent-magnet brake that engages automatically when the 24 V supply is absent. Position feedback is provided by an absolute value encoder, which allows the control system to know shaft position at startup without a homing cycle.

During standstill, the brake delivers 3.2 Nm of holding torque, which is enough to secure light vertical loads without mechanical clamps. It releases when a controller energizes the coil with 24 VDC at a brake current of 0.56 A. When the shaft is blocked at startup, the motor draws a locked-rotor current of 1.3 A and can produce immediate stall torque to overcome static friction. Two NTC temperature sensors embedded in the windings monitor thermal rise and pass that information to the drive for protective response. The permanent-magnet design and encoder feedback help maintain closed-loop stability during repeated starts, stops, and low-speed positioning moves.