Bosch Rexroth Synchronous Servo Motor MHD112B-058-PG1-AN for Automated Production Line

Bosch Rexroth MHD112B-058-PG1-AN Synchronous Servo Motor
(Order Number: R911276732)

Overview

The Bosch Rexroth MHD112B-058-PG1-AN is a high-performance synchronous servo motor engineered for precision motion control in industrial automation applications. As part of the MHD series, this motor combines robust construction, advanced electromagnetic design, and seamless integration with Rexroth’s digital drive systems. It is ideal for use in machine tools, robotics, packaging machinery, and other applications demanding high torque, dynamic response, and reliability. The “PG1-AN” suffix indicates specific encoder and winding configurations tailored for precise positioning and operational efficiency.

Key Features

• High Torque Density: Compact design delivers high torque relative to frame size.

• Dynamic Performance: Low rotor inertia enables rapid acceleration and deceleration.

• Absolute Encoder: Integrated multiturn absolute encoder (HSF type) for precise position feedback without homing after power loss.

• Robust Protection: Standard IP65 protection against dust and water jets; optional sealing air for IP67 in harsh environments.

• Flexible Cooling: Natural convection cooling (IP65); optional blower for enhanced heat dissipation (not suitable for high-shock applications).

• Safety Compliance: CE marked and cURus listed for global regulatory acceptance.

• Plug-and-Play Integration: Motor parameters stored in encoder memory for automatic configuration with Rexroth drives.

Technical Specifications

The MHD112B-058-PG1-AN is designed for demanding operational conditions. Key technical parameters are summarized below:

Design and Construction

The motor features a B05 flange design (per DIN 42950) with a plain output shaft (standard) for vibration-free operation and compatibility with clamp-type couplings. An optional featherkey (DIN 6885) is available for applications requiring positive torque transmission. The housing is finished with a black prime coat (RAL 9005) resistant to weathering, diluted acids, and lyes. Additional painting is not permitted to avoid impairing thermal performance.

A radial shaft sealing ring (DIN 3760, FPM/Viton material) protects against oil and coolant ingress. For aggressive environments, a sealing air connection (option) can be installed to maintain IP67 protection by creating an internal overpressure (0.1–0.2 bar).

Cooling and Thermal Management

The motor is designed for natural convection cooling (IP65). For applications with high cyclic loads (e.g., frequent start-stop cycles), an axial blower (e.g., LEMD-RB112B2XX) can be attached. Note: Motors with blowers are unsuitable for high-shock applications (e.g., presses, punches). Liquid cooling is not available for this model.

Encoder and Feedback System

The MHD112B-058-PG1-AN includes a multiturn absolute encoder (HSF) with a resolution of 4,194,304 increments per revolution and an accuracy of ±0.5 angular minutes. This encoder retains absolute position data even after power loss, eliminating the need for re-homing. Motor parameters (e.g., type code, control loop settings) are stored in the encoder memory, enabling automatic configuration with compatible Rexroth drives (e.g., HDC, HDS series).

Installation and Mounting

The motor supports multiple mounting positions per EN 60034-7:

• IM B5: Flange-mounted, shaft horizontal

• IM V1: Flange-mounted, shaft vertical (downward)

• IM V3: Flange-mounted, shaft vertical (upward) — Avoid fluid accumulation at the shaft seal.

Recommended mounting screws: M12 (4 pieces) with a tightening torque of 87 Nm (grade 8.8). Ensure the flange mating surface is clean and free of burrs.

Electrical Connections

Power and encoder connectors are located on the motor flange. The power connector (INS0480 or INS0380, depending on cable cross-section) features a bayonet locking mechanism for secure connection. The encoder connector (INS0613) can be rotated in 90° increments to optimize cable routing. Pre-assembled cable sets are available from Rexroth to ensure compatibility and reduce installation time.

Application Notes

• Ambient Conditions: Rated for 0°C to +45°C and altitudes up to 1000m above sea level. Derating is required beyond these limits (refer to Fig. 16-1 in the documentation).

• Vibration/Shock: Complies with IEC 60721-3-3 for stationary use. Sinusoidal vibration limits: 20 m/s² (transverse), 1 m/s² (longitudinal). Shock load limits: 250 m/s² (transverse), 40 m/s² (longitudinal).

• Holding Brake: Optional electrically released brake for holding applications. Not for operational braking. Requires 24 VDC ±10% control.

• Bearing Life: Nominal bearing life is 30,000 hours (L₁₀ₕ) under rated loads. Avoid redundant bearing arrangements to prevent premature failure.

Ordering Information

• Ordering Code: MHD112B-058-PG1-AN

• R911276732 (Complete motor unit)

• Optional Blower: LEMD-RB112B2XX (ordered separately or pre-mounted)

• Sealing Air Kit: Available via accessory sets (e.g., SUP-M01-MHD for INS0480 flange)

Conclusion

The Bosch Rexroth MHD112B-058-PG1-AN synchronous servo motor offers a blend of high torque, precision, and durability, making it ideal for advanced motion control applications. Its absolute encoder, robust protection, and compatibility with Rexroth’s digital drive ecosystem ensure easy integration, reduced commissioning time, and reliable operation.