Siemens 1FK7103-2AC71-1QB0 SIMOTICS S 1FK7-CT 36 Nm 2000 rpm Servo Motor with Brake

The Siemens 1FK7103-2AC71-1QB0 is a SIMOTICS S 1FK7-CT synchronous servo motor rated at 5.2 kW with a 36 Nm standstill torque at 2000 rpm nominal speed. It runs from a 600 V DC bus, mounts in IM B5 (IM V1, IM V3) configuration with Flange 1, carries a Drive-CLiQ absolute single-turn 20-bit encoder (AS20DQI), IP64 protection, and includes an integrated holding brake.

Technical Specifications

Selection Notes

This QB0 variant adds an integrated holding brake to the 1FK7-CT 36 Nm / 2000 rpm winding, so it holds position on a vertical or overhung-load axis when drive power is removed; where a brake is not required and the servo drive alone supplies holding torque, the brake-less version in the same frame is the lighter option. The brake raises moment of inertia to 112.000 kgcm2 and lowers shaft torsional stiffness to 108,000 Nm/rad compared with the same winding without a brake, both of which factor into servo loop tuning. The 20-bit single-turn Drive-CLiQ encoder (AS20DQI) delivers absolute position feedback without a separate battery-backed multi-turn module.