Introduction
The Allen-Bradley MPL-B320P-SK74AA Servo Motor is part of the MP-Series MPL family of low-inertia brushless servo motors developed for demanding industrial motion-control applications.
This model combines a 100 mm Frame 3, 50.8 mm magnet stack, and 5000 RPM rated speed. It is designed for applications where accurate position control, rapid speed changes, and reliable servo feedback are important.
The MPL-B320P-SK74AA uses a single-turn high-resolution encoder. The encoder provides 1024 Sin/Cos cycles per revolution and uses the Hiperface protocol, allowing compatible servo drives to obtain detailed motor position feedback for closed-loop control.
A defining mechanical feature is the keyless shaft extension. Unlike the MPL-B320P-SJ74AA, which uses a keyed shaft, the SK74AA is designed for coupling systems that do not depend on a shaft key. The machine coupling should therefore be selected specifically for the keyless shaft configuration.
The motor also includes an integrated 24 V DC holding brake. This makes it suitable for vertical axes and gravity-loaded mechanisms where the motor shaft needs to remain stationary when the servo motor is not energized. The brake should primarily be regarded as a holding mechanism rather than the normal means of dynamically stopping a moving load.
The SpeedTEC DIN right-angle connector provides additional installation flexibility. Its 180° rotatable design can make cable routing easier in machines with limited clearance around the motor.
The motor has approximately 3.05 Nm continuous torque, 7.91 Nm peak torque, and approximately 1.5 kW continuous rated output. These characteristics make it suitable for a wide range of industrial automation and precision motion applications.
The MPL-B320P-SK74AA is also an important replacement configuration within the MPL family. When replacing an older motor, engineers should verify the feedback type, shaft configuration, brake requirement, voltage, mounting arrangement, and compatible servo drive rather than selecting a replacement based only on frame size.
Technical Specifications
| Parameter | Specification |
|---|---|
| Brand | Allen-Bradley |
| Manufacturer | Rockwell Automation |
| Product Family | MP-Series MPL |
| Product Type | Rotary Servo Motor |
| Model | MPL-B320P-SK74AA |
| 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 |
| Maximum Speed | 5000 RPM |
| Continuous Torque | Approx. 3.05 Nm |
| Peak Torque | Approx. 7.91 Nm |
| Continuous Rated Output | Approx. 1.5 kW |
| Feedback | Single-Turn High-Resolution Encoder |
| Feedback Resolution | Sin/Cos, 1024 cycles/rev |
| Feedback Protocol | Hiperface |
| Shaft Configuration | Keyless Shaft Extension |
| Shaft Seal | No Shaft Seal |
| 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 |
| Rotor Inertia | Approx. 9.2 × 10⁻⁵ kg·m² |
| Maximum Operating Temperature | 40°C |
| Dimensions | Not specified in the supplied product data |
| Weight | 3.70 kg (8.16 lb) |
| Lifecycle | Active |
Recommended Related Models
The following MPL-B320P models are useful when comparing feedback, shaft, and brake configurations:
- MPL-B320P-SK72AA – Single-turn high-resolution encoder, keyless shaft, no brake
- MPL-B320P-SJ72AA – Single-turn high-resolution encoder, keyed shaft, no brake
- MPL-B320P-SJ74AA – Single-turn high-resolution encoder, keyed shaft, 24 V DC brake
- MPL-B320P-RK72AA – Resolver feedback, keyless shaft, no brake
- MPL-B320P-RK74AA – Resolver feedback, keyless shaft, 24 V DC 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
The MPL-B320P-SK72AA is the closest configuration comparison because it uses the same single-turn encoder and keyless shaft arrangement but does not include the 24 V DC brake.
Popular Related Models
For Allen-Bradley MP-Series MPL servo applications, the following models are commonly compared with the MPL-B320P-SK74AA:
- Allen-Bradley MPL-B320P-SK72AA – Single-turn encoder, keyless shaft, no brake
- Allen-Bradley MPL-B320P-SJ72AA – Single-turn encoder, keyed shaft, no brake
- Allen-Bradley MPL-B320P-SJ74AA – Single-turn encoder, keyed shaft, 24 V DC brake
- Allen-Bradley MPL-B320P-RK72AA – Resolver, keyless shaft, no brake
- Allen-Bradley MPL-B320P-RK74AA – Resolver, keyless shaft, 24 V DC 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 high-resolution feedback, keyless shaft, no brake
For replacement and retrofit projects, verify the 100 mm frame, 50.8 mm magnet stack, 5000 RPM rating, single-turn encoder, keyless shaft, 24 V DC brake, 460 V armature rating, and SpeedTEC DIN connector configuration before selecting an alternative motor.
