Company Information
E-mail		[email protected]
Mobile		+8615980777398
Whatsapp		+8615980777398
WeChat		15980777398

MPL-B1520U-HJ72AA Servo Motor

1. Product Overview

The MPL-B1520U-HJ72AA is a compact low-inertia brushless AC rotary servo motor belonging to the MP-Series MPL servo motor family.

It is a 460 V-class motor with a 63 mm frame size, 50.8 mm magnet stack, and 7000 rpm rated speed. The motor is designed for high-performance motion-control systems where fast acceleration, repeatable positioning, and controlled rotary motion are required.

The HJ72AA configuration is characterized by a 2000-line incremental encoder, a keyed shaft, a right-angle SpeedTEC DIN connector, and no integrated holding brake.

The motor is intended for closed-loop servo applications. The encoder continuously provides feedback to the motion-control system so that the servo drive can regulate speed, torque, and position.

The low-inertia construction is particularly useful for machinery that performs frequent acceleration, deceleration, indexing, reversing, and positioning operations.

The model is also notable as a discontinued configuration. The HJ72AA designation has been superseded in the product lifecycle by another MPL configuration, so it is particularly relevant today for equipment maintenance, existing-machine replacement, retrofit work, and spare-parts identification.

---

2. Brand and Product Series

Item	Specification
Brand	Allen-Bradley
Product Family	MP-Series
Product Series	MPL Low-Inertia Brushless Servo Motors
Product Type	AC Rotary Servo Motor
Model	MPL-B1520U-HJ72AA
Motor Construction	Brushless permanent-magnet servo motor
Voltage Class	460 V AC
Frame Size	63 mm
Magnet Stack	50.8 mm
Speed Class	7000 rpm
Feedback	2000-line incremental encoder
Shaft	Keyed shaft
Brake	No integrated brake
Connector	SpeedTEC DIN, right-angle
Connector Adjustment	180° rotatable
Mounting	IEC metric
Mounting Hole Type	Free mounting holes / Type FF
Motor Category	Low-inertia servo motor
Application	Industrial motion control

The MPL family is designed around compact, brushless, low-inertia servo motors.

The series is intended for applications where a conventional induction motor does not provide the positioning accuracy, acceleration response, or closed-loop control required by the machine.

The low-inertia construction allows the motor to respond quickly to commands from the servo drive.

---

3. Detailed Technical Parameters

Parameter	Specification
Model	MPL-B1520U-HJ72AA
Brand	Allen-Bradley
Product Series	MP-Series MPL
Motor Type	Low-inertia brushless AC rotary servo motor
Voltage Class	460 V AC class
Rated Speed	7000 rpm
Frame Size	63 mm
Magnet Stack Length	50.8 mm
Stack Designation	20
Feedback	2000-line incremental encoder
Feedback Type	Incremental encoder
Shaft Configuration	Keyed shaft extension
Shaft Seal	No shaft seal in standard configuration
Brake	No brake
Connector	SpeedTEC DIN connector
Connector Style	Right-angle
Connector Rotation	Approximately 180°
Mounting Flange	IEC metric
Mounting Hole Type	Free mounting holes / Type FF
Rated Output	Approx. 0.27 kW
Continuous Stall Torque	Approx. 0.49 Nm
Peak Stall Torque	Approx. 1.58 Nm
Approx. Continuous Current	Approx. 1.8 A
Rotor Inertia	Approx. 0.000013 kg·m²
Standard Protection	Approximately IP50 configuration
Enhanced Protection	Up to IP66 with appropriate sealing configuration
Approx. Frame Envelope	63 × 63 mm
Approx. Overall Length	Approx. 165 mm
Approx. Dimensions	Approx. 63 × 63 × 165 mm
Approx. Weight	Approx. 1.2 kg
Motor Technology	Permanent-magnet brushless
Mounting Orientation	Flange mounted
Operating Environment	Industrial machinery
Application Type	Closed-loop servo motion

The 63 mm frame size and 50.8 mm magnet stack are two of the most important mechanical characteristics of this model.

The motor belongs to the 7000 rpm class, making it suitable for applications where high rotational speed and rapid dynamic response are required.

The approximately 0.27 kW output class, approximately 0.49 Nm continuous stall torque, and approximately 1.58 Nm peak stall torque make the motor appropriate for compact motion axes where the load is relatively controlled and rapid movement is more important than very high continuous torque.

The approximate physical envelope is 63 × 63 × 165 mm, while the approximate weight is 1.2 kg. Exact shaft projection, mounting-hole position, connector clearance, and total installation envelope should be confirmed against the applicable mechanical drawing before machine fabrication.

---

4. Model Number Explanation

The model designation contains several configuration identifiers.

Code	General Meaning
MPL	MPL low-inertia brushless servo motor family
B	460 V-class motor
15	63 mm frame size
20	50.8 mm magnet stack
U	7000 rpm speed class
H	2000-line incremental encoder configuration
J	Keyed shaft configuration
7	SpeedTEC DIN right-angle connector
2	No integrated brake
AA	Standard configuration designation

The model number is important when selecting replacement equipment because two motors may have the same frame and stack dimensions but use different feedback systems.

The H configuration is particularly important because this motor uses a 2000-line incremental encoder.

This makes it different from MPL models using single-turn high-resolution or multi-turn high-resolution feedback.

For replacement purposes, the encoder arrangement should therefore be checked carefully rather than selecting a motor only by voltage, frame size, or rpm.

---

5. Feedback System

The MPL-B1520U-HJ72AA uses a 2000-line incremental encoder.

The encoder provides feedback to the servo control system regarding the rotational position and movement of the motor shaft.

Unlike a simple open-loop motor, the servo system continuously compares commanded motion with actual motor feedback.

This closed-loop operation allows the drive to correct errors in speed and position during operation.

The incremental encoder configuration is particularly suitable for conventional servo applications where the drive and control architecture are designed around incremental feedback.

Because feedback type is a fundamental part of servo compatibility, a motor using a different encoder configuration should not automatically be considered a direct replacement.

---

6. Motor Speed

The motor has a 7000 rpm speed class.

This relatively high speed makes the motor useful for fast indexing and rotary motion.

High motor speed can also be advantageous when the machine uses a reduction gearbox.

For example, the motor can operate at a relatively high rotational speed while a gearbox converts that speed into a lower output speed with increased mechanical torque.

Actual operating speed should be selected according to the machine load, acceleration profile, duty cycle, motor temperature, servo-drive configuration, and applicable performance curve.

---

7. Low-Inertia Design

The low-inertia design is one of the main characteristics of the MPL series.

Motor inertia determines how much torque is required to accelerate the motor rotor itself.

A lower-inertia rotor can change speed quickly.

This is particularly useful for machinery that repeatedly performs short movements.

Examples include:

• Indexing systems
• Pick-and-place equipment
• Packaging machinery
• Rotary positioning mechanisms
• Labeling equipment
• Assembly equipment
• High-speed feeders
• Electronic synchronization systems

When a machine repeatedly accelerates and decelerates, low rotor inertia can help the servo system achieve rapid dynamic response.

---

8. Shaft Configuration

The MPL-B1520U-HJ72AA uses a keyed shaft extension.

The keyed shaft provides a positive mechanical interface for suitable couplings, pulleys, sprockets, gearboxes, or other machine components.

The mechanical coupling should be properly aligned with the motor shaft.

Incorrect alignment can create excessive radial or axial loads.

These loads can increase bearing stress and may reduce the operating life of the motor.

The motor is supplied in the standard configuration without a shaft seal.

For environments containing moisture, coolant, dust, or washdown fluids, the sealing arrangement should therefore be considered carefully.

---

9. Connector Configuration

The motor uses a right-angle SpeedTEC DIN connector.

The connector arrangement is rotatable through approximately 180 degrees.

This is useful in compact machines because servo motors are often installed in restricted spaces.

The connector can be oriented to improve cable routing and reduce interference with adjacent mechanical components.

The cable should be routed so that it does not experience excessive bending, pulling, abrasion, or contact with hot or moving components.

---

10. Brake Configuration

The MPL-B1520U-HJ72AA does not have an integrated holding brake.

This is an important difference when comparing the motor with an EJ74AA or other brake-equipped configuration.

A non-brake servo motor is suitable for many horizontal motion applications where the mechanical load does not need to be held after servo power is removed.

For vertical axes or gravity-loaded mechanisms, however, the machine designer must consider how the load will be mechanically held when the servo is disabled.

Depending on the machine design, an external brake, counterbalance, mechanical locking mechanism, or another safety-related holding arrangement may be required.

The absence of an integrated motor brake should therefore be considered during the initial axis design rather than after installation.

---

11. Environmental Protection

The standard motor configuration is associated with an approximately IP50-level enclosure arrangement.

The motor can be configured with additional sealing provisions to achieve a higher level of environmental protection.

With appropriate shaft sealing and sealed cable arrangements, protection can be increased substantially, including applications requiring an IP66-level configuration.

The absence of a standard shaft seal is therefore relevant when the motor is installed in dusty, wet, coolant-exposed, or washdown environments.

Environmental protection should always be evaluated as part of the complete installation.

Motor enclosure, shaft seal, cable connector, mounting orientation, and machine enclosure all contribute to the actual protection of the installed system.

---

12. Product Applications

12.1 Packaging Machinery

The MPL-B1520U-HJ72AA can be used in packaging machinery where fast and repeatable motion is required.

Typical applications include indexing mechanisms, feeders, film-handling systems, labeling mechanisms, and product positioning.

The 7000 rpm speed class allows the motor to support high-cycle operation.

The low-inertia construction is especially useful where the machine performs repeated acceleration and deceleration.

---

12.2 Assembly Equipment

Automated assembly machines frequently require precise positioning over short distances.

The motor can be used for rotary axes, indexing mechanisms, positioning stages, feeders, and other controlled movements.

The incremental encoder allows the servo drive to monitor actual motor motion continuously.

---

12.3 Material Handling

The motor can be used in automated material-handling machinery where accurate positioning is required.

Examples include transfer mechanisms, indexing conveyors, positioning systems, and automated feeders.

The relatively compact 63 mm frame can also be useful where machine space is limited.

---

12.4 Printing and Converting

Printing and converting machines often require synchronized rotary movement.

Servo motors are used for rollers, positioning systems, web-handling mechanisms, and coordinated axes.

The encoder feedback allows the servo system to maintain controlled speed and position relationships between axes.

---

12.5 Rotary Indexing Systems

Rotary indexing equipment requires rapid acceleration, controlled stopping, and repeatable positioning.

The low-inertia design of the MPL-B1520U-HJ72AA makes it suitable for this type of motion.

The motor can be coupled directly to the mechanism or connected through a gearbox depending on the required torque and speed.

---

12.6 Automated Feeders

High-speed feeders often perform short repeated movements.

The motor’s high-speed capability and low inertia make it suitable for applications where rapid cycling is required.

The exact motor size should be selected according to feeder mass, acceleration, cycle time, and mechanical transmission characteristics.

---

12.7 Machine Tools

The motor can be used for auxiliary machine-tool motion where controlled servo positioning is required.

Potential applications include indexing, auxiliary positioning, tool-related movement, feeders, and other controlled rotary mechanisms.

The final selection should be based on the complete torque-speed requirement rather than speed alone.

---

13. Main Product Advantages

13.1 Compact 63 mm Frame

The 63 mm frame provides a relatively compact mechanical package.

This is useful in machines where several servo axes must be installed within a limited amount of space.

Compact motors can help reduce overall machine dimensions and simplify mechanical integration.

---

13.2 High-Speed 7000 rpm Operation

The 7000 rpm speed class allows the motor to perform rapid rotary movement.

This is useful for high-cycle machines and applications involving frequent indexing.

---

13.3 Low Rotor Inertia

Low rotor inertia allows the motor to accelerate and decelerate rapidly.

This can improve the dynamic response of the machine, especially when the load inertia is properly matched to the motor.

---

13.4 Incremental Encoder Feedback

The 2000-line encoder provides closed-loop feedback for the servo drive.

This enables the control system to monitor actual motor movement and correct deviations from the commanded motion.

---

13.5 Keyed Shaft

The keyed shaft provides a conventional mechanical interface.

This makes it practical for coupling the motor to gearboxes, pulleys, couplings, and other mechanical transmission components.

---

13.6 Rotatable Right-Angle Connector

The 180-degree rotatable connector provides installation flexibility.

This can be particularly useful in compact machinery where cable clearance is limited.

---

13.7 Suitable for Existing Machine Maintenance

Because this model has reached discontinued status, its primary value today is often associated with maintenance and replacement of existing equipment.

Where a machine was originally designed around this motor, identifying the exact model can be important because feedback, shaft, connector, voltage, and stack configuration all affect compatibility.

---

14. Related Models in the Same Series

The following models are closely related MPL configurations.

Model	Voltage	Frame	Stack	Speed	Feedback	Brake	Approx. Dimensions	Approx. Weight
MPL-B1510V-HJ72AA	460 V	63 mm	25.4 mm	8000 rpm	2000-line incremental	No	Approx. 63 × 63 mm frame, shorter body	Approx. 1.0 kg
MPL-B1520U-EJ72AA	460 V	63 mm	50.8 mm	7000 rpm	Single-turn high-resolution	No	Approx. 63 × 63 × 165 mm	Approx. 1.2 kg
MPL-B1520U-VJ72AA	460 V	63 mm	50.8 mm	7000 rpm	Multi-turn high-resolution	No	Approx. 63 × 63 × 165 mm	Approx. 1.2 kg
MPL-B1530U-EJ72AA	460 V	63 mm	76.2 mm	7000 rpm	Single-turn high-resolution	No	Approx. 63 × 63 mm frame, longer body	Approx. 1.4 kg
MPL-B1530U-VJ72AA	460 V	63 mm	76.2 mm	7000 rpm	Multi-turn high-resolution	No	Approx. 63 × 63 mm frame, longer body	Approx. 1.4 kg

These models are useful alternatives when the machine requirement changes.

The MPL-B1510V configuration uses a shorter stack and higher 8000 rpm speed class.

The MPL-B1520U configuration uses the 50.8 mm stack and 7000 rpm speed class.

The MPL-B1530U configuration uses the longer 76.2 mm stack and is therefore useful when a longer active magnetic stack is required.

The E and V feedback configurations should be distinguished carefully from the HJ72AA incremental-feedback version.

---

15. Five Same-Brand Models for Comparison

The following five models provide useful comparison points within the same brand’s servo-motor range.

Model	Series	Voltage	Frame	Stack	Speed	Feedback	Brake	Approx. Dimensions	Weight
MPL-B1510V-EJ72AA	MP-Series MPL	460 V	63 mm	25.4 mm	8000 rpm	Single-turn high-resolution	No	Approx. 63 × 63 mm frame, short body	Approx. 1.0 kg
MPL-B1510V-EJ74AA	MP-Series MPL	460 V	63 mm	25.4 mm	8000 rpm	Single-turn high-resolution	24 V DC	Approx. 63 × 63 mm frame, short body	Approx. 1.0 kg
MPL-B1520U-EJ74AA	MP-Series MPL	460 V	63 mm	50.8 mm	7000 rpm	Single-turn high-resolution	24 V DC	Approx. 63 × 63 × 165 mm	Approx. 1.2 kg
MPL-B1520U-VJ74AA	MP-Series MPL	460 V	63 mm	50.8 mm	7000 rpm	Multi-turn high-resolution	24 V DC	Approx. 63 × 63 × 165 mm	Approx. 1.2 kg
MPL-B1530U-EJ74AA	MP-Series MPL	460 V	63 mm	76.2 mm	7000 rpm	Single-turn high-resolution	24 V DC	Approx. 63 × 63 mm frame, longer body	Approx. 1.5 kg

These models demonstrate several common configuration changes within the MPL range.

The EJ72AA configuration provides the non-brake version, while the EJ74AA configuration adds a 24 V DC holding brake.

The VJ configuration uses a multi-turn high-resolution feedback arrangement.

The longer MPL-B1530U configuration provides a longer magnet stack while retaining the 7000 rpm speed class.

---

16. HJ72AA Compared with EJ72AA

The difference between the HJ72AA and EJ72AA configurations is particularly important.

Parameter	MPL-B1520U-HJ72AA	MPL-B1520U-EJ72AA
Voltage Class	460 V	460 V
Frame Size	63 mm	63 mm
Stack Length	50.8 mm	50.8 mm
Speed	7000 rpm	7000 rpm
Feedback	2000-line incremental	Single-turn high-resolution
Shaft	Keyed	Keyed
Connector	SpeedTEC DIN	SpeedTEC DIN
Brake	No brake	No brake
Mounting	IEC metric	IEC metric
Approx. Dimensions	Approx. 63 × 63 × 165 mm	Approx. 63 × 63 × 165 mm
Approx. Weight	Approx. 1.2 kg	Approx. 1.2 kg

Mechanically, the two configurations are closely related.

The most significant difference is the feedback system.

The HJ72AA uses a 2000-line incremental encoder, while the EJ72AA uses a single-turn high-resolution encoder.

For this reason, they should not automatically be treated as interchangeable simply because their frame size and stack length are similar.

The servo drive and motion controller must support the feedback arrangement being used.

---

17. HJ72AA Compared with EJ74AA

The EJ74AA version adds a holding brake while also using a different feedback configuration.

Parameter	MPL-B1520U-HJ72AA	MPL-B1520U-EJ74AA
Voltage	460 V class	460 V class
Frame	63 mm	63 mm
Stack	50.8 mm	50.8 mm
Speed	7000 rpm	7000 rpm
Feedback	2000-line incremental	Single-turn high-resolution
Shaft	Keyed	Keyed
Brake	No brake	24 V DC holding brake
Connector	Right-angle SpeedTEC DIN	Right-angle SpeedTEC DIN
Approx. Dimensions	63 × 63 × 165 mm	63 × 63 × 165 mm
Approx. Weight	Approx. 1.2 kg	Approx. 1.2 kg

This comparison demonstrates why the complete catalog number matters.

The two motors may occupy a similar mechanical space, but the feedback and brake arrangements are different.

When maintaining an existing machine, replacing the HJ72AA with another configuration should therefore involve checking both the electrical interface and the mechanical installation.

---

18. Typical Machine Functions

The MPL-B1520U-HJ72AA can be considered for a variety of machine functions.

Machine Function	Typical Requirement	Relevance of MPL-B1520U-HJ72AA
Indexing	Rapid acceleration and stopping	Very suitable
Rotary positioning	Closed-loop position control	Suitable
Feeder	Repeated high-speed movement	Suitable
Conveyor positioning	Controlled acceleration	Suitable
Assembly axis	Repeatable movement	Suitable
Packaging axis	High cycle rate	Suitable
Roller drive	Controlled rotary speed	Suitable
Auxiliary machine axis	Compact servo control	Suitable
Pick-and-place mechanism	Low moving inertia	Suitable
Vertical axis	Position holding	Requires separate holding solution because there is no integrated brake

---

19. Selection and Replacement Considerations

When replacing an existing MPL-B1520U-HJ72AA, the complete model number should be considered.

The first factor is voltage.

The motor belongs to the 460 V-class configuration, so the drive must be compatible with the appropriate voltage class.

The second factor is feedback.

The original motor uses a 2000-line incremental encoder.

A replacement motor with an absolute encoder or another feedback technology may require a different drive configuration or may not be electrically compatible.

The third factor is shaft configuration.

The HJ72AA uses a keyed shaft, so the replacement should provide the appropriate shaft interface for the existing coupling or transmission.

The fourth factor is brake configuration.

The HJ72AA has no integrated brake.

If the machine depends on an external brake or mechanical locking mechanism, that arrangement should be preserved.

The fifth factor is physical envelope.

The 63 mm frame and 50.8 mm stack are important dimensions, but the complete motor length, shaft projection, connector clearance, and mounting-hole pattern should also be checked.

---

20. Mechanical Installation

The motor should be mounted on a rigid machine surface.

The mounting structure should be capable of handling the reaction forces generated by acceleration and deceleration.

The coupling should be correctly aligned.

Angular, parallel, or axial misalignment can increase bearing loads and vibration.

The motor should not be used to support mechanical loads for which the shaft and bearings were not designed.

Adequate clearance should also be provided around the connector.

The right-angle connector can be rotated, but it still requires sufficient space for the cable and connector body.

---

21. Maintenance

Routine maintenance should include inspection of the motor mounting hardware, shaft coupling, connector, cable, and general operating condition.

Abnormal vibration, unusual bearing noise, excessive temperature, encoder faults, and unexpected position errors should be investigated.

The encoder cable should be protected from mechanical damage.

Connector contamination should also be avoided.

For applications exposed to moisture or coolant, the shaft and connector sealing arrangement should be inspected periodically.

Because the HJ72AA is a discontinued configuration, maintaining an existing machine may also require careful spare-part planning.

---

22. Important Advantages for Existing Equipment

The MPL-B1520U-HJ72AA remains particularly relevant when maintaining machinery originally designed around this exact model.

Using the original motor configuration can simplify troubleshooting because the feedback system, shaft arrangement, speed class, and mechanical envelope remain consistent with the original machine design.

This can be important for older automated equipment where changing the motor configuration would also require changes to the drive setup or machine-control software.

The 63 mm frame and 50.8 mm stack also provide a relatively compact package.

For replacement work, however, the lifecycle status should be taken into account because this model is no longer a current production configuration.

---

23. Product Advantages at a Glance

Advantage	Description
Compact construction	63 mm frame provides a relatively small installation envelope
High speed	7000 rpm speed class supports fast rotary motion
Low inertia	Allows rapid acceleration and deceleration
Closed-loop operation	2000-line encoder provides motor feedback
Keyed shaft	Convenient mechanical transmission interface
Flexible connector	180° rotatable right-angle connector
Brushless design	No mechanical brushes to replace
Servo control	Suitable for accurate speed and position control
Standard IEC mounting	Familiar industrial mounting arrangement
Maintenance compatibility	Useful for existing machines designed around the MPL architecture
No integrated brake	Suitable where brake-free operation is required

---

24. Complete Product Summary

Category	MPL-B1520U-HJ72AA
Model	MPL-B1520U-HJ72AA
Brand	Allen-Bradley
Series	MP-Series MPL
Product Type	Low-inertia brushless AC rotary servo motor
Voltage Class	460 V AC
Frame Size	63 mm
Magnet Stack	50.8 mm
Rated Speed	7000 rpm
Output	Approx. 0.27 kW
Continuous Stall Torque	Approx. 0.49 Nm
Peak Stall Torque	Approx. 1.58 Nm
Current	Approx. 1.8 A
Feedback	2000-line incremental encoder
Shaft	Keyed shaft
Shaft Seal	None in standard configuration
Brake	No brake
Connector	SpeedTEC DIN, right-angle
Connector Rotation	180°
Mounting	IEC metric Type FF
Approx. Dimensions	63 × 63 × 165 mm
Approx. Weight	Approx. 1.2 kg
Motor Type	Permanent-magnet brushless servo
Design	Low inertia
Typical Applications	Packaging, assembly, indexing, feeders, material handling, printing and automated machinery
Lifecycle	Discontinued configuration

25. Final Product Description

The MPL-B1520U-HJ72AA is a compact 7000 rpm low-inertia brushless AC servo motor designed for closed-loop industrial motion control.

Its 63 mm frame, 50.8 mm magnet stack, and compact overall construction make it suitable for machinery where installation space is limited but rapid servo response is required.

The 2000-line incremental encoder provides the feedback necessary for closed-loop speed and position control.

The keyed shaft provides a conventional mechanical interface, while the right-angle SpeedTEC DIN connector provides additional flexibility for cable routing.

Unlike brake-equipped versions, the HJ72AA configuration has no integrated motor brake. This makes it appropriate for applications where a holding brake is not required or where the machine provides a separate mechanical holding arrangement.

Its low-inertia rotor design is particularly useful in machines with repeated acceleration, deceleration, indexing, and reversing cycles.

The approximate physical size is 63 × 63 × 165 mm, with an approximate motor weight of 1.2 kg.

For maintenance and replacement applications, the most important characteristics to match are the 460 V-class rating, 63 mm frame, 50.8 mm stack, 7000 rpm speed, 2000-line incremental encoder, keyed shaft, connector configuration, and brake-free design.

Because this particular HJ72AA configuration is discontinued, replacement selection should be performed using the complete motor and drive configuration rather than relying only on the motor’s physical dimensions.