Product Description:

The SR-A4.0125.030-10.000 is a synchronous servo motor produced by Bosch Rexroth Indramat within the SR Synchronous Servo Motors series. It delivers rotational power to automated axes that require closed-loop positioning and velocity control in factory machinery and material-handling equipment. By combining a resolver for feedback with a brushless permanent-magnet design, the unit supplies stable torque across its operating envelope while remaining compatible with Indramat digital drive controllers.

This model is cooled solely by natural convection, so correct mounting clearance is needed to let ambient air remove heat without assistance from fans or liquid circuits. During steady operation the rotor can reach a rated speed of 3000 rpm; pairing the drive with gear stages or direct-drive couplings allows that speed to be converted into the linear or angular motion demanded by the machine. A torque constant of 1.37 Nm/A links drive current to output torque, giving the control system a predictable proportional gain. If the shaft is stalled during start-up, the winding may draw up to 10.6 A; drives must supply that locked-rotor current briefly without tripping. The mounting interface uses a flange that measures 142 mm across, aligning to IM B5 housings and simplifying integration into motor adapters and gearboxes.

The motor is sealed to IP67, so the stator housing resists dust ingress and withstands temporary water immersion when gaskets and cable glands are fitted correctly. Dynamic performance is helped by a rotor inertia of 0.0030 kg m², which balances rapid acceleration with load stability. The resolver’s mechanical precision is held within ±10 arcmin, and its electronic interpolation yields 8192 incr/rev, supplying sufficient resolution for fine position loops without external encoders. Without a brake, the motor has a mass of 16 kg. Its 24 × 50 mm keyed shaft transmits up to 14.5 Nm of locked-rotor torque while remaining compatible with standard couplings.