BAUMULLER BM4443-SI1-012 43-0309-1
Product Introduction:
The BAUMULLER BM4443-SI1-012 is a servo motor from the BM44xx series equipped with a shaft-mounted single-turn absolute encoder (Hiperface). The SI1 configuration provides direct mechanical position feedback via an encoder mounted on the motor shaft. Winding 012 is designed for 230 V AC operation. Document reference 43-0309-1 identifies the associated technical data sheet.
Detailed content
Technical Specifications:
- Motor Type: Permanent Magnet Synchronous Servo Motor (PMSM)
- Cooling Method: Natural Convection (IC410)
- Encoder: Single-Turn Absolute, Hiperface, Shaft-Mounted
- Encoder Resolution: 128 periods/rev (131,072 counts/rev)
- Rated Voltage: 230 V AC (winding 012)
- Rated Speed: Up to 4,500 rpm
- Rated Torque: Approximately 1.5 Nm (continuous)
- Peak Torque: Approximately 6.0 Nm (short-term)
- Rated Power: Approximately 0.6 kW
- Insulation Class: F (155 °C)
- Protection Class: IP54 (with connector: IP65)
- Duty Cycle: S1 (Continuous)
- Shaft Diameter: 14 mm with keyway (DIN 6885-1)
- Weight: Approximately 3.3 kg
Functional Features:
- Shaft-mounted Hiperface encoder provides direct, backlash-free position feedback
- Single-turn absolute: position known immediately after power-on
- Natural cooling — silent operation
- Keyed shaft for positive mechanical drive connection
Performance Parameters:
- Maximum Continuous Torque: 1.5 Nm
- Maximum Peak Torque: 6.0 Nm (10× rated, < 1 s)
- Nominal Speed: 0 – 4,500 rpm
- Torque Constant (Kt): Approximately 0.36 Nm/A
- Back-EMF Constant (Ke): Approximately 0.36 V/(rad/s)
- Rotor Inertia (Jm): Approximately 0.00018 kg·m²
- Mechanical Time Constant (τm): Approximately 6 ms
- Electrical Time Constant (τe): Approximately 2.5 ms
Material Composition:
- Stator: M330-50A Silicon Steel, 0.5 mm, VPI-treated
- Rotor: NdFeB N42SH, segmented arc, epoxy-bonded
- Windings: Class F copper, polyimide-insulated
- Housing: Aluminum ADC12, anodized or RAL-painted
- Shaft: C45E steel, chrome-plated, keyed (DIN 6885-1)
- Bearings: FAG/SKF sealed 2RS, grease-for-life
- Encoder: Glass code disk, Hiperface electronics, aluminum housing
Structural Features:
- Front flange: 4 × M5 bolt holes, 95 mm bolt circle
- Keyed shaft: 14 mm, DIN 6885-1, 4 mm keyway
- Encoder: M23 connector, 12-pin, on non-drive end
- Cable gland: M20 × 1.5 at drive end
- Total length: Approximately 115 mm
Working Principle:
The servo amplifier drives the three-phase stator windings with sinusoidal currents, creating a rotating magnetic field. The NdFeB rotor synchronously follows, producing torque. The shaft-mounted Hiperface encoder reads absolute position from a glass code disk and transmits 131,072 counts per revolution to the drive via RS-485. The drive executes position, velocity, and torque control loops using this feedback.
Advantages:
- Direct shaft feedback — no mechanical backlash in position loop
- Absolute position — no homing required, reduces cycle time
- Compact and lightweight for 0.6 kW output
- Proven Hiperface protocol — wide drive compatibility
Applicable Industries:
- CNC Machine Tool Axes
- Pick-and-Place Machines
- Labeling Machines
- Small Robot Axes
- Semiconductor Wafer Handling
- Medical Device Automation
Compatible Drives:
- BAUMULLER BM4621, BM4623, BM4661, BM4663
- BAUMULLER BM4700, BM4710, BM4720
Installation Requirements:
- Mounting: 4 × M5, torque 2.5 Nm
- Shaft coupling: Flexible coupling, max 0.1 mm radial / 0.1° angular misalignment
- Encoder cable: Shielded twisted pair, max 10 m, separated from power cables
- Grounding: Dedicated PE, < 0.1 Ω
Usage Precautions:
- Encoder alignment is factory-set — do not rotate encoder housing relative to shaft
- Maximum shaft load: 50 N axial, 100 N radial
- Ambient temperature: 0 – 40 °C (derate 1%/°C above 25 °C)
- Do not use on shafts with keyway damage — replace shaft if keyway is worn












