A 25 HP, three-phase inverter-duty encoder motor built for demanding variable-speed industrial applications where controlled speed and reliable torque are critical.
Modern industrial equipment increasingly relies on variable-speed control to improve productivity, process control, and operating efficiency. From conveyors and pumps to machine tools and automated production equipment, today's systems often require a motor capable of maintaining dependable torque and controlled performance across a wide range of speeds. The Marathon Y569 Blue Max® Inverter Duty Encoder Motor is designed for these demanding applications.
With 25 HP output, three-phase construction, 230/460V operation, a 284T frame, TEFC enclosure, and integrated encoder capability, the Y569 combines rugged industrial construction with advanced variable-speed performance. Marathon specifies the motor for constant-torque inverter operation up to 2000:1, making it a strong choice for applications where precise speed control is essential.
Why Inverter-Duty Motors Matter
A conventional general-purpose motor is often selected for applications that operate at relatively constant speeds. Modern industrial systems may require much greater flexibility. A variable-speed motor system may need to:
- Adjust operating speed
- Maintain torque as speed changes
- Accelerate and decelerate smoothly
- Respond to changing loads
- Reverse direction
- Operate continuously at reduced speeds
- Integrate with automated control systems
An inverter-duty motor is specifically designed to work with an appropriate variable-frequency drive or vector drive. The Y569 is built around this type of application.
Technical Specifications
| Specification | Details |
|---|---|
| Catalog Number | Y569 |
| Model | 284THFPA8028 |
| Output | 25 HP (18.7 kW) |
| Phase | 3-Phase |
| Voltage | 230/460V |
| Frequency | 60 Hz |
| Synchronous Speed | 1800 RPM |
| Full-Load Speed | 1765 RPM |
| Frame | 284T |
| Enclosure | TEFC |
| Efficiency | 91.7% |
| Service Factor | 1.0 |
| Insulation | Class H |
| Duty | Continuous |
| Ambient | 40°C |
| IP Rating | IP43 |
| Mounting | Rigid base |
| Frame Material | Cast iron |
| Rotation | Reversible |
| Constant-Torque Inverter Load | 2000:1 |
| Bearings | 6311 (drive end) / 6210 (opposite drive end) |
| Shaft | 1.875" dia., 4.81" extension |
| Certifications | UL Recognized, CSA, CE |
Key Features of the Marathon Y569
25 HP of Controlled Industrial Power
The Y569 delivers 25 HP, or approximately 18.7 kW, at 60 Hz. Its approximately 1765 RPM full-load speed makes it suitable for a wide range of four-pole industrial applications where controlled speed and substantial motor torque are required. Potential applications include conveyors, pumps, compressors, machine tools, material-handling equipment, processing machinery, automated production systems, and industrial fans and blowers. The motor's inverter-duty design allows it to be incorporated into systems where motor speed needs to vary according to the production process.
2000:1 Constant-Torque Capability
One of the standout characteristics of the Y569 is its 2000:1 constant-torque inverter load rating. A wide constant-torque range can be valuable in applications where the motor must operate at significantly different speeds while continuing to deliver the torque required by the load. For example, an automated conveyor may need to operate slowly during positioning and then accelerate to a higher production speed. A properly configured inverter system can provide this type of control while the Y569 is designed to support the demanding motor operating requirements.
TEFC Enclosure for Industrial Applications
The Y569 features a Totally Enclosed Fan Cooled (TEFC) enclosure. TEFC construction encloses the motor's internal components while using an external fan to provide cooling. This design helps protect the motor from many common industrial contaminants and makes TEFC motors popular across a wide range of industrial environments. The Y569 has an IP43 rating, so the actual environmental suitability should always be evaluated against the installation conditions and application requirements.
Class H Insulation for Inverter Operation
The Y569 uses Class H insulation and is identified by Marathon as a squirrel-cage inverter-duty motor. The insulation system is important because inverter-fed motors can experience electrical stresses that differ from those encountered during direct-on-line operation. A properly selected inverter-duty motor, combined with appropriate drive setup, grounding, cabling, and installation practices, can help provide reliable operation in variable-speed applications.
Cast-Iron Construction
The Y569 uses a cast-iron frame, providing a rugged mechanical structure for industrial applications. Cast-iron construction can be particularly useful in applications involving continuous operation, mechanical vibration, heavy loads, industrial production environments, material handling, and processing equipment. For facilities looking for a robust 25 HP inverter-duty motor, this construction provides a strong foundation for demanding service.
Encoder Feedback for Improved Control
The Y569 belongs to Marathon's Blue Max Inverter Duty Encoder Motor family. Encoder-equipped motor systems can provide feedback to a drive or control system regarding motor rotation. This can be particularly useful for applications requiring controlled speed, accurate positioning, consistent operation under changing loads, automated motion, rapid acceleration and deceleration, and closed-loop control. Instead of simply commanding the motor to operate at a particular speed, a feedback-based system can monitor actual motor performance and make appropriate control adjustments.
91.7% Efficiency
The Y569 is listed with 91.7% efficiency. For motors operating continuously, efficiency can have a meaningful impact on overall electrical consumption. Higher motor efficiency can help facilities reduce electrical losses, improve operating economics, reduce wasted energy, manage motor heat, and improve overall system efficiency. Actual energy savings depend on load, operating hours, drive efficiency, speed, and the overall mechanical system.
Continuous-Duty & Reversible Operation
The Y569 is rated for continuous duty at a 40°C ambient temperature, making it suitable for industrial equipment that operates for extended periods. It is also specified with reversible rotation, which can benefit machinery that requires controlled forward and reverse movement — such as conveyors, material-handling equipment, machine tools, automated machinery, and processing systems. The appropriate reversing method should always follow the motor and drive manufacturer's instructions.
Rigid-Base Mounting
The Y569 uses rigid mounting and a 284T NEMA frame, which makes mechanical compatibility an important consideration when replacing an existing motor. Before selecting the Y569 as a replacement, verify frame size, shaft diameter, shaft extension, base dimensions, coupling, mounting arrangement, rotation, overall motor dimensions, and motor weight. Marathon lists a 1.875-inch shaft diameter and 4.81-inch shaft extension for the Y569. A motor with the same horsepower and RPM is not necessarily a direct replacement if the frame and mounting dimensions are different.
Ideal Applications for the Y569
Conveyors
Variable-speed conveyors can benefit from controlled acceleration, deceleration, and adjustable operating speeds.
Pumps
Compatible pumping systems can use VFD control to adjust motor speed according to process requirements.
Compressors
Variable-speed compressor applications can benefit from controlled motor operation and adjustable output.
Machine Tools
Machine tools may require controlled speed and torque during different stages of a machining process.
Material Handling
Automated material-handling equipment can benefit from variable-speed control and reversible operation.
Automated Production Equipment
The combination of inverter-duty construction and encoder feedback makes the Y569 suitable for applications requiring more sophisticated motor control.
Y569 vs. Y569A: An Important Difference
Marathon also offers the Y569A, which is very similar to the Y569.
| Specification | Y569 | Y569A |
|---|---|---|
| HP | 25 HP | 25 HP |
| Voltage | 230/460V | 230/460V |
| Speed | 1800 RPM class | 1800 RPM class |
| Frame | 284T | 284T |
| Enclosure | TEFC | TEFC |
| Product Family | Blue Max® Encoder | Blue Max® Encoder |
| Model | 284THFPA8028 | 284THFCD8028 |
Marathon lists both as 25 HP Blue Max® Inverter Duty Encoder Motors, but they have different model numbers. If you're replacing an existing motor, do not assume Y569 and Y569A are interchangeable solely because the horsepower, voltage, frame, and enclosure appear similar. Verify the complete catalog/model number and mechanical/electrical requirements.
Y569 vs. Y570
The Y570 is the next larger motor in this Blue Max family.
| Specification | Y569 | Y570 |
|---|---|---|
| Horsepower | 25 HP | 30 HP |
| Voltage | 230/460V | 230/460V |
| Frame | 284T | 286T |
| Enclosure | TEFC | TEFC |
| Speed Class | 1800 RPM | 1800 RPM |
| Application | Inverter Duty Encoder | Inverter Duty Encoder |
Marathon's current product listings identify Y569 as the 25 HP/284T model and Y570 as the 30 HP/286T model. The difference in frame size means they should not be treated as direct replacements without checking the equipment.
Signs It's Time to Consider an Inverter-Duty Upgrade
Industrial facilities may want to evaluate an existing motor if they experience:
- Poor low-speed performance
- Excessive motor heating
- Unstable speed
- Frequent VFD faults
- Poor acceleration or deceleration
- Excessive vibration
- Bearing problems
- Difficulty maintaining torque
- Frequent motor failures
- Increasing maintenance costs
- Production interruptions
A properly specified inverter-duty motor can provide a better match for equipment requiring variable-speed operation.
Why Choose the Marathon Y569?
The Y569 brings together several features designed for demanding variable-speed applications: 25 HP output, 230/460V operation, 1800 RPM synchronous / 1765 RPM full-load speed, a 284T frame, TEFC enclosure, 91.7% efficiency, Class H insulation, cast-iron construction, a continuous-duty rating, 2000:1 constant-torque capability, an encoder-equipped design, reversible rotation, rigid-base mounting, ball bearings, F1/F2-capable assembly, and UL Recognized / CSA / CE certification. Together, these characteristics make the Y569 a versatile solution for industrial systems requiring controlled variable-speed operation.
Why Buy from KPaul Motors?
At KPaul Motors, we help industrial contractors, engineers, maintenance professionals, facility managers, automation specialists, and procurement teams source dependable electric motors. When sourcing the Marathon Y569, customers can benefit from:
- Competitive pricing on genuine industrial motors
- Support identifying the correct motor specifications
- Assistance sourcing inverter and vector-duty motors
- Support for commercial and industrial applications
- Experienced industrial customer service
- Access to trusted motor manufacturers
Whether you're replacing a VFD motor, upgrading a conveyor, sourcing a motor for a pump or compressor, or planning an industrial automation project, KPaul Motors can help you identify the appropriate motor solution.
Final Thoughts
The Marathon Y569 Blue Max® Inverter Duty Encoder Motor is a 25 HP, three-phase motor designed for demanding variable-speed industrial applications. With 230/460V operation, 1765 RPM full-load speed, a 284T frame, TEFC enclosure, Class H insulation, cast-iron construction, 91.7% efficiency, encoder-equipped design, and a 2000:1 constant-torque inverter load rating, the Y569 is built for applications where controlled speed and reliable torque are critical. Its combination of rugged construction and advanced inverter-duty capability makes it suitable for conveyors, pumps, compressors, machine tools, material-handling equipment, processing machinery, and automated industrial systems. For facilities looking for a 25 HP motor capable of supporting sophisticated variable-speed operation, the Marathon Y569 provides a strong combination of power, feedback, control, and industrial durability.
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🔹 Buy the Marathon Y569 Blue Max® Inverter Duty Encoder Motor Today — Model 284THFPA8028 · 25 HP | 1765 RPM | 230/460V | 284T Frame | TEFC | 2000:1 Constant Torque
🔹 Explore More Inverter & Vector Duty Motors — KPaul Motors