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Allen-Bradley MPL-B4540F-SK74AA Low-Inertia Servo Motor – Technical Specifications, Applications, Advantages and Model Selection Guide

1. Product Overview

The Allen-Bradley MPL-B4540F-SK74AA is a high-performance AC rotary servo motor belonging to the MP-Series MPL low-inertia servo motor family.

It is designed for industrial motion-control applications where accurate positioning, rapid acceleration and deceleration, stable speed regulation, compact mechanical integration and reliable servo performance are required.

The motor uses a 130 mm frame with a 101.6 mm magnet stack and is rated for 3000 rpm operation. Its continuous stall torque is approximately 10.2 N·m, with a peak torque capability of approximately 27.1 N·m. The motor has a continuous output rating of approximately 2.6 kW.

The SK74AA configuration combines a single-turn high-resolution feedback device, keyless shaft construction, a 24 V DC holding brake and a right-angle SpeedTEC DIN connector arrangement.

This configuration makes the motor particularly suitable for machinery where the motor must deliver relatively high torque from a compact frame while maintaining accurate electronic motion control.

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2. Brand and Series

Item	Specification
Brand	Allen-Bradley
Product Family	MP-Series
Servo Motor Series	MPL Low-Inertia Servo Motors
Product Type	AC Rotary Servo Motor
Model	MPL-B4540F-SK74AA
Voltage Class	460/480 V AC class
Motor Construction	Brushless permanent-magnet servo motor
Frame Size	130 mm
Magnet Stack Length	101.6 mm
Rated Speed	3000 rpm
Feedback	Single-turn high-resolution encoder
Shaft Configuration	Keyless shaft
Brake	24 V DC brake
Connector	SpeedTEC DIN, right-angle configuration
Mounting	IEC metric flange mounting
Mounting Holes	Free mounting holes, Type FF
Intended Application	Industrial servo motion control

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3. Detailed Technical Parameters

3.1 Electrical and Performance Specifications

Parameter	Specification
Model	MPL-B4540F-SK74AA
Motor Type	Brushless AC rotary servo motor
Voltage Class	460/480 V AC
Rated Speed	3000 rpm
Maximum Speed	3000 rpm
Continuous Stall Torque	10.2 N·m
Peak Stall Torque	27.1 N·m
Continuous Rated Power	Approx. 2.6 kW
Rotor Inertia	Approx. 0.00052 kg·m²
Continuous Stall Current	Approx. 9.1 A
Peak Stall Current	Approx. 29 A
Feedback Type	Single-turn high-resolution encoder
Feedback Resolution	Sin/Cos, 1024 cycles/rev class
Feedback Protocol	Hiperface-type absolute feedback
Brake Voltage	24 V DC
Brake	Integrated holding brake
Shaft	Keyless
Shaft Seal	Typically without shaft seal
Connector	SpeedTEC DIN
Connector Direction	Right-angle
Connector Rotation	180° rotatable
Mounting Standard	IEC metric
Protection Class	IP65-class motor construction
Cooling	Natural convection / machine-mounted cooling
Frame Size	130 mm
Magnet Stack	101.6 mm
Approx. Overall Dimensions	Approx. 209 × 446 × 251 mm, depending on connector/brake configuration
Approx. Weight	Approx. 9–10 kg
Application Voltage	High-voltage industrial servo systems

The 10.2 N·m continuous torque rating gives the motor a useful continuous-load capability for medium-duty machine axes.

The approximately 27.1 N·m peak torque capability provides additional short-duration torque for acceleration, deceleration, indexing and transient load conditions.

The combination of approximately 2.6 kW output and 3000 rpm makes the motor a practical choice for applications requiring both moderate torque and relatively high operating speed.

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4. Mechanical Dimensions and Weight

The physical size of the motor is based around the 130 mm frame and 101.6 mm stack-length configuration.

Mechanical Parameter	Specification
Model	MPL-B4540F-SK74AA
Frame Diameter / Frame Size	130 mm
Frame Class	Frame 45
Magnet Stack Length	101.6 mm
Mounting	IEC metric flange
Shaft Type	Keyless
Brake	24 V DC integrated brake
Connector Type	SpeedTEC DIN
Connector Position	Right angle
Connector Adjustment	180° rotatable
Approx. Overall Length	Approx. 446 mm*
Approx. Overall Width	Approx. 209 mm*
Approx. Overall Height	Approx. 251 mm*
Approx. Motor Weight	Approx. 9–10 kg
Mounting Hole Style	Free mounting holes, Type FF

*Overall package/envelope dimensions can vary depending on the connector orientation and configuration. For detailed mechanical installation, the applicable mechanical drawing should be used rather than relying only on catalog envelope dimensions.

The 130 mm frame provides a relatively substantial mechanical platform while the 101.6 mm stack keeps the motor within a practical size range for medium-power servo axes.

The keyless shaft is particularly useful when the mechanical transmission uses a clamping hub, shrink disc or other shaft-clamping mechanism rather than a traditional keyed coupling.

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5. Model Number Explanation

The model designation MPL-B4540F-SK74AA contains configuration information describing the motor construction and options.

Model Section	Meaning
MPL	MP-Series low-inertia servo motor family
B	High-voltage / 460 V-class motor family
45	130 mm frame-size class
40	101.6 mm magnet stack
F	3000 rpm motor configuration
S	Single-turn high-resolution feedback
K	Keyless shaft configuration
7	SpeedTEC DIN right-angle connector configuration
4	24 V DC brake configuration
AA	Standard configuration suffix

The model code is useful when selecting a replacement motor because seemingly similar MPL motors can differ in feedback type, shaft construction, brake configuration, connector arrangement and stack length.

For replacement work, the complete catalog number should therefore be matched rather than selecting a motor only from the frame size and power rating.

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6. Product Introduction

The Allen-Bradley MPL-B4540F-SK74AA is built for demanding industrial servo applications where controlled acceleration, accurate positioning and repeatable dynamic performance are important.

The MPL low-inertia architecture is particularly useful in machines where the motor must repeatedly change speed.

A lower motor rotor inertia allows the servo system to accelerate and decelerate the motor more efficiently. This is valuable in indexing equipment, automated machinery, packaging systems, electronic assembly equipment and other applications with frequent motion changes.

The 3000 rpm rated speed provides a good balance between torque and rotational speed. Instead of focusing exclusively on very high-speed operation, the B4540F motor provides a useful combination of approximately 10.2 N·m continuous torque and approximately 27.1 N·m peak torque.

The integrated 24 V DC brake is another important feature of the SK74AA configuration.

The brake is primarily intended as a holding function when the servo axis is stopped or when the machine requires the motor shaft to remain stationary under gravity or other external loads. It should not normally be treated as the primary dynamic stopping device.

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7. Low-Inertia Servo Design

One of the main characteristics of the MPL series is its low-inertia rotor design.

Servo systems frequently operate through repeated acceleration and deceleration cycles. Every time the motor changes speed, the drive must overcome the inertia of the motor rotor and the connected mechanical load.

Reducing motor rotor inertia can improve the responsiveness of the overall motion system.

For the MPL-B4540F-SK74AA, the rotor inertia is approximately 0.00052 kg·m².

This makes the motor suitable for applications where the machine axis must respond quickly to command changes.

The actual machine performance, however, depends on the complete reflected load inertia, gearbox ratio, coupling characteristics, mechanical friction and servo-drive tuning.

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8. 3000 RPM Operating Speed

The motor is designed around a rated speed of 3000 rpm.

This speed range is well suited to many industrial servo applications.

Typical applications include:

• Rotary indexing.
• Conveyor positioning.
• Packaging machinery.
• Pick-and-place mechanisms.
• Machine-tool auxiliary axes.
• Material handling.
• Printing and converting equipment.
• Automated assembly.
• Electronic production machinery.
• Industrial winding and feeding systems.

The 3000 rpm rating also provides sufficient rotational speed for applications where a gearbox, belt drive or ballscrew is used to convert rotary motor motion into the required machine-axis movement.

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9. Continuous and Peak Torque Performance

The motor provides approximately 10.2 N·m continuous stall torque and approximately 27.1 N·m peak stall torque.

Continuous torque is the more important value when evaluating the motor for a sustained mechanical load.

Peak torque is important during short-duration events such as acceleration, rapid deceleration, overcoming transient friction and handling temporary increases in machine load.

The approximately 27.1 N·m peak torque capability is substantially higher than the continuous torque rating, giving the servo system useful short-term torque headroom.

However, peak torque should not be treated as a continuous operating rating. The actual permissible duration and repetition rate depend on the servo drive, motor thermal conditions, ambient temperature, load profile and operating cycle.

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10. High-Resolution Single-Turn Feedback

The SK74AA configuration uses a single-turn high-resolution feedback system.

Feedback is fundamental to servo operation because the drive continuously monitors motor position and speed.

The feedback system allows the control system to determine:

• Motor position.
• Rotational speed.
• Direction of rotation.
• Position error.
• Motion profile tracking.
• Dynamic response.

High-resolution feedback is particularly valuable in positioning applications where small angular movements must be detected accurately.

The single-turn configuration is appropriate when the control architecture can establish or manage the required machine reference position without relying on a multi-turn absolute position count through power cycles.

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11. Keyless Shaft Design

The MPL-B4540F-SK74AA uses a keyless shaft.

This is an important difference compared with keyed versions of the same motor family.

A keyless shaft can be advantageous when the mechanical coupling is based on a clamping connection.

Typical mechanical arrangements include:

• Clamp-type couplings.
• Shrink-disc connections.
• Precision shaft hubs.
• Servo gearboxes with clamping input systems.
• Belt pulley systems using clamping hubs.

A keyless connection can provide a clean mechanical interface and can simplify certain installation arrangements.

The exact coupling method should always be selected according to the required torque, shaft diameter, allowable overhung load, axial load and machine safety requirements.

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12. Integrated 24 V DC Brake

The SK74AA version includes a 24 V DC holding brake.

The brake is particularly useful for vertical axes.

For example, when a vertical axis is stopped, gravity may attempt to move the machine downward. The integrated brake can help hold the motor shaft when the servo drive is disabled or when the machine requires a mechanical holding function.

Typical applications include:

• Vertical lifting axes.
• Z-axis mechanisms.
• Vertical transfer systems.
• Automated handling equipment.
• Hoist-type positioning mechanisms.
• Packaging machinery with vertical motion.
• Assembly equipment with elevated tooling.

The brake should be correctly controlled according to the drive and machine safety architecture. It should not be used as a substitute for an engineered emergency-stop or safety-braking system.

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13. SpeedTEC DIN Connector

The motor uses a SpeedTEC DIN connector configuration.

The right-angle connector arrangement helps reduce the amount of space required around the rear of the motor compared with some straight connector configurations.

The connector can also be rotated through approximately 180°, providing additional flexibility when routing motor and feedback cables.

This is especially useful in machines with:

• Restricted cable routing space.
• Compact motor compartments.
• Multiple adjacent servo axes.
• Moving machine assemblies.
• Tight cabinet-to-machine cable paths.

Proper connector orientation can significantly simplify machine wiring and reduce unnecessary cable bending.

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14. IEC Metric Mounting

The motor uses IEC metric mounting.

This provides a standardized mechanical approach for integrating the motor with machine frames, gearboxes, couplings and other mechanical components.

The 130 mm frame provides a practical size for medium-power industrial servo applications while maintaining compatibility with compact machine architectures.

When replacing an existing motor, the mounting pattern, shaft dimensions, shaft extension, connector clearance and brake requirements should all be checked rather than comparing only the motor power.

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15. Main Product Advantages

15.1 High Torque from a Compact Frame

The motor provides approximately 10.2 N·m of continuous torque and approximately 27.1 N·m of peak torque from a 130 mm frame.

This makes it suitable for machine axes where available installation space is limited but the axis still requires substantial torque.

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15.2 Fast Dynamic Response

The low-inertia design helps the motor respond quickly to servo commands.

This is particularly beneficial for repeated indexing and positioning operations.

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15.3 3000 rpm Operating Capability

The 3000 rpm rating provides a useful combination of speed and torque.

It can support both direct-drive-style applications and mechanically geared applications.

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15.4 Integrated Brake

The 24 V DC brake makes the SK74AA configuration suitable for many applications where shaft holding is required.

This is especially useful on vertical machine axes.

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15.5 High-Resolution Feedback

The single-turn high-resolution encoder provides precise feedback for closed-loop servo control.

This supports accurate positioning and stable speed regulation.

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15.6 Keyless Shaft

The keyless shaft provides flexibility for modern clamping-type mechanical transmission systems.

It can be particularly convenient when the machine uses precision couplings or clamping hubs.

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15.7 Flexible Connector Orientation

The right-angle SpeedTEC DIN connector can be rotated, helping engineers adapt cable routing to the machine layout.

This can reduce installation problems in compact equipment.

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15.8 Industrial Machine Compatibility

The MPL-B4540F-SK74AA is intended for integration into industrial automation systems where servo drives, feedback control, mechanical transmission and machine sequencing must operate as one coordinated system.

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16. Typical Applications

16.1 Packaging Machinery

The motor is well suited to packaging machines requiring repeated high-speed positioning.

Applications may include:

• Film feeding.
• Indexing.
• Cutter positioning.
• Product transfer.
• Labeling.
• Sealing mechanisms.
• Cartoning.
• Rotary indexing.

The low-inertia characteristics can help maintain rapid cycle times.

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16.2 Material Handling

Material-handling equipment often requires controlled acceleration and deceleration.

The motor can be used for:

• Conveyor positioning.
• Transfer mechanisms.
• Lift axes.
• Shuttle systems.
• Sorting mechanisms.
• Automated loading equipment.

The integrated brake is particularly useful where the axis must remain stationary when power or servo enable is removed.

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16.3 Automated Assembly Equipment

Assembly machines frequently require precise positioning over relatively short travel distances.

The MPL-B4540F-SK74AA can be applied to:

• Pressing mechanisms.
• Rotary assembly stations.
• Pick-and-place systems.
• Component insertion.
• Tool positioning.
• Workpiece indexing.

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16.4 Machine Tools

Servo motors are widely used for controlled machine-tool movements.

Potential applications include:

• Auxiliary positioning axes.
• Feed mechanisms.
• Tool-changing mechanisms.
• Indexing systems.
• Material-feed systems.

The 3000 rpm operating range makes the motor suitable for applications where controlled speed and positioning are more important than extremely high spindle speed.

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16.5 Printing and Converting Equipment

Printing and converting systems often require accurate synchronization between multiple axes.

The motor can be considered for:

• Web feeding.
• Roll positioning.
• Cutter synchronization.
• Material indexing.
• Tension-control mechanisms.
• Registration systems.

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16.6 Electronics Manufacturing Equipment

Electronics manufacturing machines commonly require precise, repeatable movement.

Applications may include:

• Component handling.
• Inspection stages.
• Positioning tables.
• Assembly stations.
• Feeder mechanisms.
• Automated transfer systems.

The high-resolution feedback system is useful in applications where positioning repeatability is important.

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16.7 Vertical Motion

Because this version includes a 24 V DC brake, it is particularly suitable for selected vertical-axis applications.

Examples include:

• Z-axis positioning.
• Vertical transfer.
• Lifting mechanisms.
• Vertical tooling.
• Material elevators.
• Automated storage systems.

The actual safety architecture should include appropriate mechanical and electrical protection for the specific vertical axis.

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17. Selection Considerations

When selecting the MPL-B4540F-SK74AA, several factors should be checked.

Motor Load

The continuous load should remain within the motor’s continuous torque capability.

For repetitive motion, the complete duty cycle should be considered rather than evaluating only the maximum instantaneous torque.

Acceleration

If the machine requires aggressive acceleration, peak torque must be considered together with load inertia.

Reflected Inertia

Gearboxes, pulleys, ballscrews and other transmission components can significantly change the inertia seen by the motor.

Brake Requirements

If the motor is installed on a vertical axis, the brake requirement should be carefully evaluated.

Shaft Configuration

The SK74AA uses a keyless shaft. If the existing machine requires a keyed shaft, another model configuration may be more appropriate.

Feedback Requirements

The SK74AA uses single-turn high-resolution feedback. Applications requiring multi-turn absolute position retention may require a different feedback configuration.

Cable Routing

The right-angle SpeedTEC connector is advantageous in compact machinery, but the available clearance should still be checked before installation.

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18. Recommended Related Models in the Same MPL Series

The following models are useful alternatives when comparing torque, feedback, shaft and brake configurations.

Model	Frame / Stack	Speed	Continuous Torque	Peak Torque	Power	Feedback	Shaft	Brake	Approx. Weight
MPL-B4540F-SJ72AA	130 / 101.6 mm	3000 rpm	10.2 N·m	27.1 N·m	2.6 kW	Single-turn high-resolution	Keyed	No	Approx. 8.6 kg
MPL-B4540F-SJ74AA	130 / 101.6 mm	3000 rpm	10.2 N·m	27.1 N·m	2.6 kW	Single-turn high-resolution	Keyed	24 V DC	Approx. 9.5 kg
MPL-B4540F-SK72AA	130 / 101.6 mm	3000 rpm	10.2 N·m	27.1 N·m	2.6 kW	Single-turn high-resolution	Keyless	No	Approx. 9.0 kg
MPL-B4530F-SK72AA	130 / 76.2 mm	3000 rpm	8.25 N·m	20.3 N·m	Approx. 2.1 kW	Single-turn high-resolution	Keyless	No	Approx. 7.3 kg
MPL-B4560F-SK72AA	130 / 152.4 mm	3000 rpm	14.1 N·m	34.4 N·m	3.2 kW	Single-turn high-resolution	Keyless	No	Approx. 11–12 kg

The MPL-B4540F-SJ72AA is a logical choice when the same basic torque and speed are required but a keyed shaft is preferred.

The MPL-B4540F-SJ74AA adds the 24 V DC brake while retaining the keyed shaft.

The MPL-B4540F-SK72AA is the closest configuration to the SK74AA because it retains the same frame, stack, feedback and keyless shaft arrangement but removes the brake.

The MPL-B4530F-SK72AA is a smaller-stack alternative when approximately 8.25 N·m of continuous torque is sufficient.

The MPL-B4560F-SK72AA provides a larger stack and approximately 14.1 N·m continuous torque when additional torque capacity is required.

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19. Five Popular / Widely Used Allen-Bradley MPL Models

Model	Frame / Stack	Speed	Continuous Torque	Peak Torque	Power	Feedback	Shaft	Brake	Approx. Weight
MPL-B4540F-MJ74AA	130 / 101.6 mm	3000 rpm	10.2 N·m	27.1 N·m	2.6 kW	Multi-turn absolute	Keyed	24 V DC	Approx. 10–11 kg
MPL-B4540F-MK74AA	130 / 101.6 mm	3000 rpm	10.2 N·m	27.1 N·m	2.6 kW	Multi-turn absolute	Keyless	24 V DC	Approx. 10–12 kg
MPL-B4540F-HJ74AA	130 / 101.6 mm	3000 rpm	10.2 N·m	27.1 N·m	2.6 kW	High-resolution incremental	Keyed	24 V DC	Approx. 10–11 kg
MPL-B4560F-MJ74AA	130 / 152.4 mm	3000 rpm	14.1 N·m	34.4 N·m	3.2 kW	Multi-turn absolute	Keyed	24 V DC	Approx. 12–13 kg
MPL-B540K-MJ74AA	165 / 101.6 mm	4000 rpm	19.4 N·m	48.6 N·m	5.4 kW	Multi-turn absolute	Keyed	24 V DC	Approx. 15 kg

These models cover several common combinations of frame size, torque capacity, feedback technology, shaft design and brake configuration.

For machines that require absolute position information across multiple motor revolutions, the MPL-B4540F-MJ74AA and MPL-B4540F-MK74AA are particularly relevant alternatives.

For higher torque requirements, the MPL-B4560F-MJ74AA provides a larger stack within the same general 130 mm frame class.

For applications requiring significantly greater torque and a higher 4000 rpm speed rating, the MPL-B540K-MJ74AA moves into a larger motor class.

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20. Direct Comparison with Closely Related Models

Parameter	MPL-B4540F-SK74AA	MPL-B4540F-SK72AA	MPL-B4540F-SJ74AA	MPL-B4540F-MK74AA
Frame	130 mm	130 mm	130 mm	130 mm
Stack	101.6 mm	101.6 mm	101.6 mm	101.6 mm
Speed	3000 rpm	3000 rpm	3000 rpm	3000 rpm
Continuous Torque	10.2 N·m	10.2 N·m	10.2 N·m	10.2 N·m
Peak Torque	27.1 N·m	27.1 N·m	27.1 N·m	27.1 N·m
Power	2.6 kW	2.6 kW	2.6 kW	2.6 kW
Feedback	Single-turn	Single-turn	Single-turn	Multi-turn
Shaft	Keyless	Keyless	Keyed	Keyless
Brake	24 V DC	None	24 V DC	24 V DC
Connector	SpeedTEC DIN	SpeedTEC DIN	SpeedTEC DIN	SpeedTEC DIN
Approx. Weight	9–10 kg	Approx. 9 kg	Approx. 9.5 kg	Approx. 10–12 kg

The MPL-B4540F-SK74AA can therefore be viewed as a balanced configuration when the application needs a keyless shaft, high-resolution single-turn feedback and an integrated brake.

If the brake is not required, the SK72AA version can reduce the motor configuration complexity.

If a keyed shaft is required, the SJ74AA becomes a more suitable alternative.

If multi-turn absolute feedback is preferred, the MK74AA is a logical alternative while retaining the keyless shaft and brake combination.

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21. Application Selection Guide

Application Requirement	Recommended Model
Keyless shaft + single-turn feedback + brake	MPL-B4540F-SK74AA
Keyless shaft + single-turn feedback + no brake	MPL-B4540F-SK72AA
Keyed shaft + single-turn feedback + brake	MPL-B4540F-SJ74AA
Keyed shaft + single-turn feedback + no brake	MPL-B4540F-SJ72AA
Keyless shaft + multi-turn absolute feedback + brake	MPL-B4540F-MK74AA
Keyed shaft + multi-turn absolute feedback + brake	MPL-B4540F-MJ74AA
Higher torque within 130 mm frame class	MPL-B4560F-MJ74AA
Higher speed and larger motor class	MPL-B540K-MJ74AA

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22. Why the MPL-B4540F-SK74AA Is a Good General-Purpose Servo Choice

The main strength of the MPL-B4540F-SK74AA is its balanced specification.

It is not simply a high-power motor. Instead, it combines a useful 3000 rpm speed rating, approximately 10.2 N·m continuous torque, approximately 27.1 N·m peak torque, low rotor inertia, high-resolution feedback, keyless shaft construction and an integrated 24 V brake.

This combination makes it suitable for a broad range of industrial machine axes.

The 130 mm frame is also large enough to provide useful torque without moving immediately into a much larger motor package.

For machine designers, this can be important because motor size affects not only the motor itself but also:

• Machine-frame dimensions.
• Gearbox size.
• Coupling selection.
• Cable routing.
• Cabinet and machine-space requirements.
• Mechanical mounting.
• Overall machine weight.

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23. Installation and Engineering Considerations

Before installing the motor, the machine designer should verify the mechanical interface.

The mounting flange, mounting-hole arrangement, shaft diameter, shaft extension, connector clearance and brake configuration should all be checked against the machine design.

The electrical system should also be evaluated as a complete servo system.

The motor should be paired with a compatible servo drive and feedback interface. Drive sizing should consider continuous current, peak current, acceleration requirements, duty cycle and thermal conditions.

The brake wiring should be designed according to the machine’s control and safety requirements.

Cable routing is also important. Although the right-angle connector provides useful flexibility, the cable must maintain an appropriate bending radius and should not be subjected to excessive mechanical stress.

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24. Thermal Considerations

The 2.6 kW continuous power rating should not be interpreted as an unlimited output under every environmental condition.

Motor temperature depends on:

• Continuous torque.
• Average torque.
• Operating speed.
• Duty cycle.
• Ambient temperature.
• Machine enclosure.
• Cooling conditions.
• Installation orientation.
• Cable and drive conditions.

Applications involving frequent peak torque operation should be evaluated using the complete motion profile.

A machine that repeatedly accelerates, decelerates and reverses direction may have a relatively modest average speed while still producing substantial thermal loading.

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25. Servo Tuning Considerations

The low-inertia characteristics of the MPL motor can support responsive servo control, but the drive must still be correctly tuned for the actual mechanical load.

The following factors can influence servo tuning:

• Motor inertia.
• Reflected load inertia.
• Gear ratio.
• Coupling stiffness.
• Ballscrew characteristics.
• Belt elasticity.
• Mechanical backlash.
• Friction.
• External disturbance.
• Required positioning accuracy.
• Acceleration and deceleration profile.

A properly matched motor and load generally produces better dynamic performance than simply selecting a motor based on peak torque alone.

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26. Key Advantages at a Glance

Feature	Benefit
130 mm frame	Compact medium-power servo platform
101.6 mm stack	Balanced torque and physical size
3000 rpm	Suitable for many industrial motion axes
10.2 N·m continuous torque	Strong continuous-load capability
27.1 N·m peak torque	Useful acceleration and transient-load margin
Approx. 2.6 kW power	Suitable for medium-duty servo applications
Low rotor inertia	Fast dynamic response
Single-turn high-resolution feedback	Accurate position and speed control
Keyless shaft	Flexible mechanical coupling options
24 V DC brake	Useful for holding and vertical-axis applications
SpeedTEC DIN connector	Compact industrial connection
180° rotatable connector	Flexible cable routing
IEC metric mounting	Convenient machine integration

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27. Overall Product Evaluation

The Allen-Bradley MPL-B4540F-SK74AA is a well-balanced low-inertia industrial servo motor for medium-power motion-control applications.

Its most important characteristics are the 130 mm frame, 101.6 mm stack, 3000 rpm rated speed, approximately 10.2 N·m continuous torque, approximately 27.1 N·m peak torque, approximately 2.6 kW continuous output, single-turn high-resolution feedback, keyless shaft and integrated 24 V DC brake.

The combination of keyless mechanical integration and brake functionality makes this configuration particularly useful for automated machinery where the motor must both respond quickly to servo commands and hold the mechanical axis when required.

Compared with the brake-free SK72AA, the SK74AA provides an additional holding function.

Compared with the keyed SJ74AA, the SK74AA provides a keyless shaft.

Compared with the multi-turn MK74AA, the SK74AA uses a single-turn high-resolution feedback configuration.

This makes the SK74AA a particularly useful choice when the machine architecture specifically calls for keyless mechanical coupling + single-turn high-resolution feedback + 24 V DC brake + 3000 rpm operation.

For applications requiring a similar torque level but a different mechanical or feedback arrangement, the broader MPL family provides several closely related configurations.

For applications requiring more torque, the longer-stack B4560F family is a natural step upward.

For applications requiring higher speed and significantly greater power, the larger B540K class provides another direction for motor selection.

Overall, the MPL-B4540F-SK74AA is best suited to industrial servo axes where compact installation, responsive motion, repeatable positioning, moderate-to-high continuous torque and integrated shaft holding are all important requirements.