Introduction
The Allen-Bradley MPL-B320P-RK74AA Servo Motor is part of the Allen-Bradley MP-Series MPL family of low-inertia brushless servo motors. It is designed for 480 VAC-class industrial motion systems and combines a 100 mm frame with a 50.8 mm magnet stack and a 5000 RPM speed rating.
The RK74AA configuration is distinguished by its combination of resolver feedback, keyless shaft extension, and 24 V DC holding brake. This makes it particularly useful when a machine requires robust feedback and mechanical load holding while maintaining a keyless mechanical interface.
The motor provides approximately 3.05 Nm of continuous torque and approximately 1.5 kW continuous rated output. When combined with a compatible Allen-Bradley servo drive and motion controller, it can provide closed-loop control of speed, torque, acceleration, deceleration, and position.
The integrated 24 V DC brake is an important feature for applications involving vertical or gravity-loaded axes. The brake is intended primarily for holding the shaft when the motor is not energized rather than for routine dynamic stopping. The servo system and machine safety architecture should therefore be designed so that the brake is used according to the applicable motor and drive requirements.
The keyless shaft extension differentiates this model from the closely related MPL-B320P-RJ74AA, which uses a keyed shaft. When replacing an existing motor, the mechanical shaft configuration should therefore be checked carefully before installation.
The SpeedTEC DIN right-angle connector also provides useful flexibility during machine installation. Its rotatable design can make cable routing easier where space around the motor is restricted.
Because the MPL-B320P family includes resolver, single-turn, and multi-turn feedback options as well as keyed and keyless shaft configurations, the complete catalog number should always be verified before selecting a replacement motor.
Technical Specifications
| Parameter | Specification |
|---|---|
| Brand | Allen-Bradley |
| Manufacturer | Rockwell Automation |
| Product Family | MP-Series MPL |
| Product Type | Rotary Servo Motor |
| Model | MPL-B320P-RK74AA |
| Motor Type | Low-Inertia Brushless Servo Motor |
| Voltage Class | 480 VAC |
| Armature Voltage | 460 V |
| Frame Size | 100 mm / Frame 3 |
| Magnet Stack Length | 50.8 mm (2.0 in.) |
| Rated Speed | 5000 RPM |
| Continuous Torque | Approx. 3.05 Nm |
| Peak Torque | Approx. 7.91 Nm |
| Continuous Rated Output | Approx. 1.5 kW |
| Feedback | 2-Pole Resolver |
| Shaft Configuration | Keyless Shaft Extension |
| Brake | 24 V DC Holding Brake |
| Connector | SpeedTEC DIN Right-Angle Connector |
| Connector Rotation | 180° Rotatable |
| Mounting | IEC Metric |
| Mounting Holes | Free Mounting Holes, Type FF |
| Shaft Seal | No Shaft Seal |
| Enclosure | IP66 |
| Operating Temperature | 0 to 40°C |
| Dimensions | Not specified in the supplied product data |
| Weight | 3.70 kg (8.16 lb) |
| Lifecycle | Active Mature |
Recommended Related Models
The following MPL-B320P models are useful for comparing different feedback, shaft, and brake configurations:
- MPL-B320P-RK72AA – Resolver feedback, keyless shaft, no brake
- MPL-B320P-RJ72AA – Resolver feedback, keyed shaft, no brake
- MPL-B320P-RJ74AA – Resolver feedback, keyed shaft, 24 V DC brake
- MPL-B320P-MK72AA – Multi-turn high-resolution feedback, keyless shaft, no brake
- MPL-B320P-MK74AA – Multi-turn high-resolution feedback, keyless shaft, 24 V DC brake
- MPL-B320P-MJ72AA – Multi-turn high-resolution feedback, keyed shaft, no brake
- MPL-B320P-MJ74AA – Multi-turn high-resolution feedback, keyed shaft, 24 V DC brake
- MPL-B320P-SJ72AA – Single-turn high-resolution feedback, keyed shaft, no brake
- MPL-B320P-SJ74AA – Single-turn high-resolution feedback, keyed shaft, 24 V DC brake
For replacement selection, the most important differences are the resolver versus encoder feedback, keyed versus keyless shaft, and brake versus non-brake configuration.
Popular Related Models
For Allen-Bradley MP-Series MPL servo motor applications, the following models are commonly compared with the MPL-B320P-RK74AA:
- Allen-Bradley MPL-B320P-RK72AA – Resolver, keyless shaft, no brake
- Allen-Bradley MPL-B320P-RJ72AA – Resolver, keyed shaft, no brake
- Allen-Bradley MPL-B320P-RJ74AA – Resolver, keyed shaft, 24 V DC brake
- Allen-Bradley MPL-B320P-MK72AA – Multi-turn absolute feedback, keyless shaft, no brake
- Allen-Bradley MPL-B320P-MK74AA – Multi-turn absolute feedback, keyless shaft, 24 V DC brake
- Allen-Bradley MPL-B320P-MJ74AA – Multi-turn absolute feedback, keyed shaft, 24 V DC brake
- Allen-Bradley MPL-B320P-SJ72AA – Single-turn high-resolution feedback, keyed shaft, no brake
- Allen-Bradley MPL-B320P-SJ74AA – Single-turn high-resolution feedback, keyed shaft, 24 V DC brake
The MPL-B320P-RK74AA is especially suitable when the application requires a 100 mm frame, 5000 RPM speed, resolver feedback, keyless shaft, and 24 V DC holding brake. These configuration details should be matched carefully when selecting a replacement or spare motor.
