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1. Product Overview

The MPL-B1520U-VJ42AA is a low-inertia permanent-magnet AC rotary servo motor belonging to the MP-Series MPL servo motor family.

It is a compact industrial servo motor designed for applications requiring controlled speed, accurate positioning, rapid acceleration and deceleration, and dependable closed-loop motion performance.

The motor uses a 63 mm frame size and a 50.8 mm magnet stack, with a rated speed of 7000 rpm. Its motor output is approximately 0.27 kW, with approximately 0.49 Nm continuous stall torque and 1.58 Nm peak stall torque.

The most important feature distinguishing the MPL-B1520U-VJ42AA from several closely related MPL configurations is its absolute multi-turn high-resolution encoder.

The encoder uses 128 Sin/Cos signals and an absolute multi-turn feedback arrangement, making the motor suitable for motion systems where the controller needs detailed position feedback across multiple revolutions.

The motor has a keyed shaft, no standard shaft seal, and no integrated holding brake.

This brake-free configuration makes it appropriate for axes where a motor holding brake is not required or where load holding is provided separately by the machine’s mechanical system.

The model is also associated with older-generation motion-control equipment and is identified as a discontinued configuration. It remains relevant for replacement, maintenance, retrofit, and spare-motor applications involving existing equipment.

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2. Brand and Product Series

Item	Specification
Brand	Allen-Bradley
Product Family	MP-Series
Product Series	MPL Low-Inertia Brushless Servo Motors
Product Type	Permanent-magnet AC rotary servo motor
Model	MPL-B1520U-VJ42AA
Series Type	Low inertia
Voltage Class	400/460 V class
Frame Size	63 mm
Magnet Stack Length	50.8 mm
Rated Speed	7000 rpm
Motor Output	Approx. 0.27 kW
Feedback	Absolute multi-turn high-resolution encoder
Encoder Signal	128 Sin/Cos
Shaft	Keyed shaft
Shaft Seal	No shaft seal
Brake	No brake
Mounting	IEC metric
Motor Construction	Brushless permanent magnet
Application	Closed-loop industrial motion control
Lifecycle	Discontinued configuration

The MPL series is a low-inertia servo motor family intended for industrial motion applications.

Within the series, different model suffixes identify variations in feedback, shaft arrangement, brake configuration, speed, stack length, and other mechanical or electrical characteristics.

The VJ42AA configuration is specifically associated with the multi-turn absolute feedback arrangement and brake-free configuration.

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3. Detailed Technical Parameters

Parameter	Specification
Model	MPL-B1520U-VJ42AA
Brand	Allen-Bradley
Product Family	MP-Series
Product Series	MPL Low-Inertia Servo Motors
Motor Type	AC rotary servo motor
Motor Construction	Brushless permanent-magnet
Voltage Class	400/460 V class
Frame Size	63 mm
Frame Diameter Class	Approx. 63 mm
Magnet Stack Length	50.8 mm
Magnet Stack	2.0 in.
Speed Class	7000 rpm
Rated Speed	7000 rpm
Motor Output	Approx. 0.27 kW
Continuous Stall Torque	Approx. 0.49 Nm
Peak Stall Torque	Approx. 1.58 Nm
Rotor Inertia	Approx. 0.000013 kg·m²
Feedback	Absolute multi-turn high-resolution encoder
Encoder Signal	128 Sin/Cos
Encoder Interface	Hiperface-type absolute feedback
Feedback Resolution	High-resolution multi-turn
Shaft	Keyed shaft
Shaft Seal	No shaft seal
Brake	No integrated brake
Mounting Flange	IEC metric
Mounting	Free mounting holes / IEC configuration
Connector Arrangement	Multiple motor connectors
Motor Protection	Approximately IP50 standard configuration
Enhanced Protection	Higher protection possible with suitable sealing arrangements
Approx. Dimensions	66.5 × 63 × 146.2 mm
Approx. Weight	Approx. 1.2 kg
Rotation	Rotary
Design	Low inertia
Duty	Industrial servo operation
Typical Use	Precision positioning and automated motion

The 0.27 kW output class, 0.49 Nm continuous stall torque, and 1.58 Nm peak stall torque place the motor in the compact MPL-B1520U performance class.

The motor has a 63 mm frame and a 50.8 mm active magnet stack. The published mechanical dimensions for the small-frame 1520 configuration give an overall length of approximately 146.2 mm in the applicable connector arrangement, with a maximum body dimension of approximately 66.5 mm.

For practical equipment documentation, the overall envelope can therefore be described as approximately 66.5 × 63 × 146.2 mm.

The motor weight is approximately 1.2 kg for the standard non-brake B1520U motor configuration. The weight can vary depending on configuration and how the motor is packaged or measured.

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4. Model Number Explanation

The model number provides a useful description of the motor configuration.

Code	Meaning
MPL	MPL low-inertia permanent-magnet servo motor family
B	400/460 V-class motor family
15	63 mm frame
20	50.8 mm magnet stack
U	7000 rpm speed class
V	Absolute multi-turn high-resolution encoder
J	Keyed shaft
4	Brake-free configuration in this catalog family
2	Standard connector/configuration designation
AA	Standard configuration

The V in the model number is particularly important.

It identifies the motor’s absolute multi-turn feedback configuration.

The J identifies the keyed shaft arrangement.

The 42 suffix corresponds to the brake-free version of this configuration, distinguishing it from the related VJ44AA model, which incorporates a 24 V DC brake.

This is why the complete catalog number should be used when selecting a replacement.

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5. Absolute Multi-Turn Encoder

The absolute multi-turn encoder is one of the main characteristics of the MPL-B1520U-VJ42AA.

Unlike a basic incremental feedback system, an absolute multi-turn encoder is designed to provide absolute position information while also tracking position across multiple shaft revolutions.

This is useful for applications where the control system needs detailed information about the motor’s actual position.

The VJ42AA configuration uses 128 Sin/Cos signals with absolute multi-turn feedback.

This feedback arrangement can be particularly useful in coordinated motion systems, positioning equipment, indexing machinery, and applications where the motor’s absolute position is important.

The feedback device also makes this motor different from the related HJ42AA incremental-feedback configuration and EJ42AA single-turn absolute configuration.

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6. Low-Inertia Design

The MPL-B1520U-VJ42AA belongs to the low-inertia section of the MPL family.

Low rotor inertia is useful when a machine needs to change speed rapidly.

When a servo motor accelerates, some of the available torque is required to accelerate the motor rotor itself.

A lower rotor inertia reduces this portion of the acceleration requirement.

This is especially useful for:

• High-speed indexing
• Packaging machinery
• Pick-and-place systems
• Assembly equipment
• Rotary positioning
• Automated feeders
• Short-cycle machines
• Repetitive start-stop applications

The motor’s rotor inertia is approximately 0.000013 kg·m², according to the MPL-B1520U performance data.

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7. 7000 RPM Speed Capability

The motor is rated in the 7000 rpm speed class.

This makes it suitable for high-speed rotary applications.

The motor can be used in direct rotary motion or together with a mechanical transmission.

When a gearbox is used, the high motor speed can be converted into a lower machine output speed with higher output torque.

For example, a machine may use the servo motor at a relatively high rotational speed while using a reduction mechanism to drive a slower indexing mechanism.

The actual operating point should always be selected according to the load torque, acceleration, duty cycle, mechanical transmission, and motor performance curve.

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8. Motor Torque Characteristics

The MPL-B1520U-VJ42AA has approximately 0.49 Nm continuous stall torque and approximately 1.58 Nm peak stall torque.

The continuous torque value is relevant when determining whether the motor can handle the ongoing mechanical load.

The peak torque value is important during acceleration, deceleration, short-term overloads, and other transient machine operations.

A servo motor should not be selected solely according to peak torque.

The continuous load, acceleration profile, duty cycle, load inertia, mechanical efficiency, and thermal conditions all need to be considered.

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9. Shaft Configuration

The motor uses a keyed shaft.

The keyed shaft provides a conventional positive mechanical connection for suitable couplings, gearboxes, pulleys, and other transmission components.

The shaft configuration is important when replacing an existing motor because the coupling must match the shaft size, keyway, shaft projection, and mounting arrangement.

The motor is listed with no shaft seal in the standard configuration.

If the motor is installed in a wet, dusty, or coolant-exposed environment, the machine designer should consider whether additional sealing protection is required.

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10. Brake Configuration

The MPL-B1520U-VJ42AA has no integrated motor brake.

This makes it different from the related MPL-B1520U-VJ44AA configuration.

The brake-free configuration is appropriate when the axis does not need an integrated motor holding brake.

Typical examples include many horizontal rotary axes where the load does not move significantly when the servo is de-energized.

For vertical or gravity-loaded applications, however, the absence of a brake should be considered carefully.

A separate mechanical holding system may be required depending on the machine design.

The motor should not be selected for a vertical load simply because its torque rating is sufficient. The machine must also provide an appropriate method of holding the load when motor torque is unavailable.

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11. Mechanical Mounting

The MPL-B1520U-VJ42AA uses an IEC metric mounting arrangement.

The 63 mm frame provides a compact flange-mounted motor configuration.

The mounting surface should be sufficiently rigid to withstand the forces generated during acceleration and deceleration.

Correct alignment is important.

Shaft misalignment can increase radial and axial loading, generate vibration, and shorten bearing life.

The mounting bolts should be tightened according to the applicable mechanical installation requirements.

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12. Connector Arrangement

The motor uses a multi-connector arrangement appropriate for its power and feedback configuration.

The connector arrangement separates motor power and feedback functions, allowing the servo system to communicate with and control the motor correctly.

Proper cable routing is important.

Servo cables should be protected against:

• Excessive bending
• Abrasion
• Mechanical pulling
• High temperature
• Sharp edges
• Moving machine components
• Chemical exposure

The cable should also have sufficient service-loop length where the motor or connected mechanism moves.

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13. Environmental Protection

The standard motor configuration is associated with approximately IP50-level protection.

The motor has no standard shaft seal.

This makes the standard configuration more appropriate for relatively controlled industrial environments than for direct washdown applications.

For equipment exposed to moisture, coolant, dust, or other contaminants, the machine designer should evaluate the motor’s complete sealing arrangement.

The environmental rating of the complete machine should not be determined from the motor body alone.

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14. Product Applications

14.1 Packaging Machinery

The MPL-B1520U-VJ42AA can be used for controlled rotary motion in packaging equipment.

Typical functions include:

• Product indexing
• Feeder drives
• Rotary positioning
• Cutting mechanisms
• Labeling mechanisms
• Packaging synchronization
• Conveyor positioning

The low-inertia rotor helps support rapid speed changes.

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14.2 Assembly Equipment

Automated assembly systems often require multiple controlled axes.

The motor can be used for rotary positioning, indexing, feeding, and transfer mechanisms.

The absolute multi-turn encoder is useful where the control system requires detailed position feedback.

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14.3 Indexing Machines

Indexing machines frequently require fast acceleration followed by accurate positioning.

The 7000 rpm motor speed and low-inertia rotor are well suited to repeated indexing cycles.

The multi-turn encoder provides detailed feedback for closed-loop control.

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14.4 Material Handling

The motor can be used for automated material-handling equipment where accurate positioning is required.

Typical applications include:

• Transfer units
• Automated feeders
• Positioning mechanisms
• Rotary tables
• Conveyor indexing
• Pick-and-place systems

The motor’s compact 63 mm frame is also useful where installation space is limited.

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14.5 Printing and Converting Equipment

Printing and converting equipment often requires synchronized rotary movement.

Servo motors can be used for rollers, feed mechanisms, positioning systems, and auxiliary axes.

The absolute multi-turn feedback configuration provides detailed motor position information for coordinated motion.

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14.6 Machine Tools

The motor can be used for selected auxiliary machine-tool axes.

Potential applications include:

• Rotary positioning
• Indexing
• Auxiliary feed mechanisms
• Automated tool-related movement
• Controlled rotary axes

The final motor selection should be based on the actual torque-speed requirement.

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14.7 Electronics Automation

Compact servo motors are commonly useful in electronics and precision assembly machinery.

The 63 mm frame helps keep the mechanical structure compact.

The low-inertia design is useful for short travel and rapid cycling applications.

The absolute multi-turn feedback arrangement can also simplify position management in appropriately designed motion systems.

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15. Main Product Advantages

15.1 Absolute Multi-Turn Feedback

The absolute multi-turn encoder is one of the major advantages of this particular configuration.

It provides substantially more position information than a basic motor without feedback.

This is useful in coordinated positioning systems.

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15.2 Compact 63 mm Frame

The 63 mm frame provides a relatively small mechanical footprint.

This is useful in machines where multiple servo axes need to be installed in a limited space.

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15.3 50.8 mm Magnet Stack

The 50.8 mm stack provides a useful balance between motor size and torque capability.

It belongs to the mid-length configuration within the small MPL frame family.

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15.4 7000 RPM Operation

The 7000 rpm speed class allows rapid rotary movement.

This can be particularly useful in high-cycle industrial machinery.

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15.5 Low Rotor Inertia

The low rotor inertia supports rapid acceleration and deceleration.

This is valuable for machines with frequent speed changes.

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15.6 Keyed Shaft

The keyed shaft provides a familiar industrial mechanical interface.

It can be used with suitable couplings, gearboxes, pulleys, and other transmission components.

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15.7 Brake-Free Configuration

The absence of an integrated brake can be an advantage in applications that do not require motor holding.

It also eliminates the need to manage motor-brake wiring where no holding brake is required.

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16. Five Closely Related Models

The following models are closely related MPL configurations and are useful for comparison.

Model	Voltage Class	Frame	Stack	Speed	Feedback	Brake	Approx. Dimensions	Approx. Weight
MPL-B1520U-VJ42AA	400/460 V	63 mm	50.8 mm	7000 rpm	Absolute multi-turn	No	Approx. 66.5 × 63 × 146.2 mm	Approx. 1.2 kg
MPL-B1520U-VJ44AA	460 V class	63 mm	50.8 mm	7000 rpm	Absolute multi-turn	24 V DC	Approx. 66.5 × 63 × 182.3 mm*	Approx. 1.4 kg
MPL-B1520U-EJ42AA	460 V class	63 mm	50.8 mm	7000 rpm	Single-turn absolute	No	Approx. 66.5 × 63 × 146.2 mm	Approx. 1.2 kg
MPL-B1520U-EJ44AA	460 V class	63 mm	50.8 mm	7000 rpm	Single-turn absolute	24 V DC	Approx. 66.5 × 63 × 182.3 mm*	Approx. 1.4 kg
MPL-B1530U-VJ42AA	460 V class	63 mm	76.2 mm	7000 rpm	Absolute multi-turn	No	Approx. 66.5 × 63 × 171.2 mm	Approx. 1.6 kg

*For brake-equipped small-frame motors, the published mechanical dimensions add approximately 36.1 mm to the relevant motor length dimension.

The MPL-B1520U-VJ44AA is the closest functional variant because it retains the multi-turn feedback arrangement while adding a 24 V DC holding brake.

The MPL-B1520U-EJ42AA is similar mechanically but changes the feedback system from multi-turn to single-turn absolute.

The MPL-B1520U-EJ44AA combines the single-turn feedback arrangement with a holding brake.

The MPL-B1530U-VJ42AA retains multi-turn feedback and 7000 rpm operation but uses the longer 76.2 mm stack.

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17. Five Same-Brand Models for Comparison

The following are additional same-brand servo motor models that provide useful comparison points. They are presented as commonly encountered related models rather than as a ranking.

Model	Product Family	Output Class	Speed	Feedback	Brake	Frame / Stack	Approx. Dimensions	Approx. Weight
MPL-B1510V-VJ42AA	MP-Series MPL	Approx. 0.16 kW	8000 rpm	Absolute multi-turn	No	63 mm / 25.4 mm	Approx. 66.5 × 63 × 133.2 mm	Approx. 1.0 kg
MPL-B1520U-VJ44AA	MP-Series MPL	Approx. 0.27 kW	7000 rpm	Absolute multi-turn	24 V DC	63 mm / 50.8 mm	Approx. 66.5 × 63 × 182.3 mm	Approx. 1.4 kg
MPL-B1530U-EJ44AA	MP-Series MPL	Approx. 0.39 kW	7000 rpm	Single-turn absolute	24 V DC	63 mm / 76.2 mm	Approx. 66.5 × 63 × 207.3 mm	Approx. 1.8 kg
MPL-B320P-MK22AA	MP-Series MPL	Approx. 1.4 kW	5000 rpm class	Absolute multi-turn	No	100 mm frame class	Larger than B15 series	Approx. 3.7 kg
MPL-B330P-MK22AA	MP-Series MPL	Approx. 1.8 kW	5000 rpm	Absolute multi-turn	No	100 mm frame class	Larger than B15 series	Approx. 4.6 kg

The larger B320P and B330P models illustrate how the same general servo-motor family extends into higher-output applications.

The B1520U remains a much smaller motor, with approximately 0.27 kW output and a 63 mm frame.

The B1510V is shorter and operates in the 8000 rpm class.

The B1530U uses a longer stack and provides a higher torque/output class.

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18. VJ42AA Compared with VJ44AA

The most direct comparison is between the target model and the brake-equipped version.

Parameter	MPL-B1520U-VJ42AA	MPL-B1520U-VJ44AA
Voltage Class	400/460 V class	460 V class
Frame	63 mm	63 mm
Stack	50.8 mm	50.8 mm
Speed	7000 rpm	7000 rpm
Feedback	Absolute multi-turn	Absolute multi-turn
Encoder	128 Sin/Cos	128 Sin/Cos
Shaft	Keyed	Keyed
Brake	No brake	24 V DC holding brake
Shaft Seal	No shaft seal	No shaft seal
Approx. Dimensions	66.5 × 63 × 146.2 mm	Approx. 66.5 × 63 × 182.3 mm
Approx. Weight	Approx. 1.2 kg	Approx. 1.4 kg

The two models are very closely related.

The primary functional difference is the holding brake.

The brake-equipped VJ44AA is physically longer because the brake adds to the motor assembly length.

This distinction should be considered carefully when replacing one model with the other.

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19. VJ42AA Compared with EJ42AA

The EJ42AA and VJ42AA are also closely related.

Parameter	MPL-B1520U-VJ42AA	MPL-B1520U-EJ42AA
Voltage Class	400/460 V class	460 V class
Frame	63 mm	63 mm
Stack	50.8 mm	50.8 mm
Speed	7000 rpm	7000 rpm
Feedback	Absolute multi-turn	Absolute single-turn
Encoder Signal	128 Sin/Cos	High-resolution single-turn
Shaft	Keyed	Keyed
Brake	No brake	No brake
Shaft Seal	No shaft seal	No shaft seal
Approx. Dimensions	66.5 × 63 × 146.2 mm	Approx. 66.5 × 63 × 146.2 mm
Approx. Weight	Approx. 1.2 kg	Approx. 1.2 kg

The mechanical characteristics are very similar.

The major distinction is the feedback configuration.

The VJ42AA uses absolute multi-turn feedback, while the EJ42AA uses a single-turn absolute feedback configuration.

This difference is important when selecting the servo drive and control architecture.

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20. VJ42AA Compared with HJ42AA

Parameter	MPL-B1520U-VJ42AA	MPL-B1520U-HJ42AA
Voltage Class	400/460 V class	460 V class
Frame	63 mm	63 mm
Stack	50.8 mm	50.8 mm
Speed	7000 rpm	7000 rpm
Feedback	Absolute multi-turn	2000-line incremental
Shaft	Keyed	Keyed
Brake	No brake	No brake
Connector	Servo motor connector arrangement	Servo motor connector arrangement
Approx. Dimensions	66.5 × 63 × 146.2 mm	Approx. 66.5 × 63 × 146.2 mm
Approx. Weight	Approx. 1.2 kg	Approx. 1.2 kg

This comparison illustrates the importance of feedback selection.

The HJ42AA is based on incremental feedback, while the VJ42AA uses absolute multi-turn feedback.

The motors can have very similar physical dimensions while requiring different feedback interfaces and drive configurations.

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21. Typical Application Matching

Application	Main Requirement	MPL-B1520U-VJ42AA
Packaging	Rapid repetitive motion	Suitable
Indexing	Accurate position feedback	Suitable
Assembly	Repeatable positioning	Suitable
Material handling	Controlled servo motion	Suitable
Rotary tables	Position control	Suitable
Feed mechanisms	Fast cyclic movement	Suitable
Printing	Coordinated rotary motion	Suitable
Converting	Speed synchronization	Suitable
Electronics automation	Compact precision motion	Suitable
Pick-and-place	Fast positioning	Suitable
Vertical axis	Load holding	Requires separate holding solution
Heavy continuous load	High continuous torque	Motor sizing should be evaluated

The final selection should always be based on the actual machine load.

A motor that has adequate peak torque may still be unsuitable if its continuous torque capability is insufficient.

The load inertia and acceleration profile are equally important.

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22. Advantages for Machine Builders

The compact design of the MPL-B1520U-VJ42AA can simplify machine construction.

The 63 mm frame allows the motor to be mounted in relatively small machine spaces.

The 50.8 mm stack provides a practical middle configuration within the small MPL motor family.

The 7000 rpm speed class provides sufficient speed for many high-cycle automation applications.

The absolute multi-turn encoder provides detailed position feedback.

The keyed shaft allows conventional mechanical integration.

The absence of an integrated brake makes the configuration relatively straightforward for applications that do not need motor holding.

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23. Maintenance Considerations

Routine maintenance should include inspection of the motor mounting, shaft coupling, cables, connectors, bearings, and general machine condition.

The motor should be monitored for abnormal vibration.

Unusual bearing noise can indicate a developing mechanical problem.

Changes in motor temperature can also provide useful information about loading and cooling conditions.

The encoder and its cable should be protected from mechanical damage.

Feedback errors can occur if the cable or connector is damaged or improperly installed.

The keyed shaft and coupling should also be checked periodically for looseness or excessive wear.

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24. Replacement Considerations

The MPL-B1520U-VJ42AA is identified as a discontinued motor configuration.

For existing machinery, this makes accurate model identification particularly important.

The replacement motor should not be selected simply because it has the same frame size.

The following characteristics should be matched:

1. Voltage class
2. Motor speed
3. Continuous torque
4. Peak torque
5. Magnet stack
6. Encoder technology
7. Feedback interface
8. Shaft configuration
9. Brake configuration
10. Mounting dimensions
11. Connector arrangement
12. Motor cable compatibility

The feedback system deserves particular attention.

The VJ42AA uses absolute multi-turn feedback, so substituting an incremental-feedback motor can require changes to the servo drive and control configuration.

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25. Technical Specification Summary

Category	MPL-B1520U-VJ42AA
Model	MPL-B1520U-VJ42AA
Brand	Allen-Bradley
Product Family	MP-Series
Series	MPL Low-Inertia Servo Motors
Motor Type	Permanent-magnet AC rotary servo motor
Voltage Class	400/460 V class
Frame Size	63 mm
Magnet Stack	50.8 mm
Rated Speed	7000 rpm
Motor Output	Approx. 0.27 kW
Continuous Stall Torque	Approx. 0.49 Nm
Peak Stall Torque	Approx. 1.58 Nm
Rotor Inertia	Approx. 0.000013 kg·m²
Feedback	Absolute multi-turn high-resolution encoder
Encoder Signal	128 Sin/Cos
Shaft	Keyed
Shaft Seal	No shaft seal
Brake	No brake
Mounting	IEC metric
Approx. Dimensions	66.5 × 63 × 146.2 mm
Approx. Weight	Approx. 1.2 kg
Speed Class	7000 rpm
Design	Low inertia
Typical Applications	Packaging, assembly, indexing, material handling, printing, positioning and automated machinery
Lifecycle	Discontinued configuration

26. Final Product Description

The MPL-B1520U-VJ42AA is a compact 7000 rpm low-inertia AC servo motor designed for industrial motion-control applications requiring accurate and repeatable rotary movement.

Its 63 mm frame, 50.8 mm magnet stack, and approximately 0.27 kW output class make it suitable for compact machine axes where high dynamic response is more important than very high continuous power.

The most distinctive feature of this motor is its absolute multi-turn high-resolution encoder with 128 Sin/Cos feedback.

This feedback arrangement allows the servo system to obtain detailed position information across multiple motor revolutions, making the motor useful in positioning, indexing, coordinated motion, and other closed-loop automation applications.

The motor uses a keyed shaft, has no standard shaft seal, and is supplied in the brake-free VJ42AA configuration.

The lack of an integrated brake makes it suitable for many horizontal servo axes, while applications involving vertical or gravity-loaded mechanisms may require a separate holding mechanism.

The approximate mechanical envelope is 66.5 × 63 × 146.2 mm, and the motor weight is approximately 1.2 kg for the standard non-brake B1520U configuration.

The MPL-B1520U-VJ42AA is therefore best understood as a compact, low-inertia, high-speed servo motor combining a 63 mm frame, 50.8 mm stack, 7000 rpm speed class, approximately 0.27 kW output, absolute multi-turn feedback, keyed shaft, and brake-free configuration.

For replacement or retrofit work, the feedback configuration is especially important.

A motor with the same physical frame but a different encoder type should not automatically be regarded as a direct replacement.

The complete motor-drive combination, feedback interface, shaft arrangement, mounting dimensions, speed requirements, and machine load should all be checked before substitution.