AMI8121-4100-1F11 by Beckhoff

The AMI8121-4100-1F11 is a compact integrated servo drive from Beckhoff that belongs to the AMI Integrated Drive Motors series. By combining a permanent-magnet synchronous motor, a drive stage, and an EtherCAT interface in one frame, it delivers decentralized motion control without a control cabinet. This unit is intended for small-axis tasks such as format adjustment or feeder handling where tight installation space, limited wiring, and coordinated multi-axis positioning are required on modern production machines.

The drive produces a standstill torque of 0.48 Nm, enabling precise holding and low-speed positioning under load. A maximum mechanical speed of 12,000 rpm supports rapid cycle rates when acceleration reserves are used. Position feedback is delivered by a 17-bit multi-turn absolute encoder, so the controller receives 131,072 counts per revolution and retains the shaft angle across power cycles. Communication and power are routed through a single EtherCAT line; this real-time bus allows synchronous updates across distributed axes. The housing has an IP54 protection rating, guarding against limited dust ingress and water spray so the motor can be mounted directly on processing equipment without an additional enclosure.

The six-pole rotor supports synchronous operation at higher fundamental frequencies. Its pole count of 6 also reduces cogging for smooth low-speed motion. Dynamic response is aided by a rotor moment of inertia of 0.134 kgcm², minimizing torque demand during acceleration while still damping small load disturbances. The assembly weighs 1.35 kg, which eases mounting on moving carriages or robot wrists. Integrated safety supports the STO function under TwinSAFE logic, helping the machine meet SIL requirements without separate relays. A 24 V DC brake holds the axis when required, while a keyed shaft made in accordance with DIN 6885 provides positive engagement with the connected component. The unit uses convection cooling and operates at temperatures from 0 °C to 40 °C.