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Allen-Bradley 20J1F3F1K8LNDNNNNN PowerFlex 755TM 690V AFE Bus Supply

Product Overview

The Allen-Bradley 20J1F3F1K8LNDNNNNN is a high-power PowerFlex 755TM bus supply designed for large industrial drive systems that use a common DC bus architecture.

This model belongs to the high-power 690 V AC class and uses an active front-end arrangement for regenerative and low-harmonic operation. With a Normal Duty rating of approximately 1,914 kW, it is intended for large electrical systems where several motor inverters or drive sections need to share a centralized DC bus.

The unit is considerably different from a conventional standalone variable-frequency drive. Instead of directly controlling one motor, a bus supply converts incoming three-phase AC power into a controlled DC bus supply that can be distributed to multiple compatible inverter sections.

This type of architecture is useful when a plant contains several large motors, especially where centralized power distribution, regenerative energy handling, and coordinated drive operation are important.

The catalog number 20J1F3F1K8LNDNNNNN identifies a particular configuration within the PowerFlex 755TM bus-supply family. The final catalog-number positions represent configuration and option selections, so the exact installed hardware should always be checked against the unit nameplate when preparing a replacement or engineering a system.

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Basic Product Information

Parameter	Specification
Model	20J1F3F1K8LNDNNNNN
Brand	Allen-Bradley
Product Family	PowerFlex 755T
Product Series	PowerFlex 755TM
Product Type	Regenerative / AFE Bus Supply
Drive Function	Common DC Bus Supply
Input Voltage Class	690 V AC
Input Phase	3 Phase
DC Bus Output Class	1000 V DC
Normal Duty Power	Approximately 1,914 kW
Normal Duty Continuous DC Output Current	Approximately 1,914 A
Frame Size	Frame 11
Cooling	Forced Air
Enclosure Class	IP21 / UL Type 1 class
Mounting	Floor Mount
Regenerative Capability	Yes
Active Front End	Yes
Low-Harmonic Architecture	Yes
Common DC Bus	Yes
Installation Type	Large industrial cabinet system
Application Level	Heavy industrial / high-power process equipment
Typical System Architecture	Centralized AC-to-DC bus with multiple inverters

The 1,914 kW figure is the Normal Duty rating associated with the 690 V F1K8 rating. The corresponding Frame 11 bus-supply configuration is rated at approximately 1,914 A on the DC side.

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Product Series

PowerFlex 755TM

The PowerFlex 755TM series is designed around common DC bus applications.

Instead of installing a separate complete AC input section for every motor inverter, the system can use a centralized bus supply and then distribute DC power to multiple inverter sections.

For large machinery, this can make the overall electrical architecture more organized. It can also make regenerative energy management easier when several motors operate together.

The PowerFlex 755TM platform covers a wide range of power levels and frame sizes, from comparatively smaller industrial installations through very large multi-megawatt systems.

The 20J catalog prefix identifies the bus-supply portion of the PowerFlex 755TM architecture.

The F voltage designation corresponds to the 690 V AC class.

The F1K8 rating identifies the high-power Frame 11 class used by this model.

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Catalog Number Structure

The catalog number can be read as a configuration identifier rather than simply a model name.

Catalog Position / Code	Meaning
20J	PowerFlex 755TM bus supply
1	Cooling / configuration designation
F	690 V AC class
3	IP21 / UL Type 1 floor-mounted enclosure class
F1K8	690 V high-power rating, Frame 11
L	EMI/filtering configuration
N	Option position
D	Option/configuration designation
NNNNN	Additional configuration positions

The catalog number should not be interpreted by changing one character at a time without checking the complete configuration. For large PowerFlex 755TM systems, enclosure, filtering, control, precharge, bus arrangement, and other options can affect the final equipment configuration.

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Detailed Technical Specifications

Parameter	20J1F3F1K8LNDNNNNN
Model	20J1F3F1K8LNDNNNNN
Brand	Allen-Bradley
Series	PowerFlex 755TM
Product Category	Bus Supply
Input Voltage	690 V AC nominal class
Input Frequency	50 Hz class
Input Phase	3 Phase
DC Output Voltage	Up to approximately 1000 V DC class
Normal Duty Rating	1,914 kW
Normal Duty DC Current	1,914 A
Heavy Duty Rating	Approximately 1,500 kW
Heavy Duty DC Current	Approximately 1,576 A
Frame	11
Cooling Method	Forced Air
Enclosure	IP21 / UL Type 1 class
Installation	Floor standing
Power Conversion	Active Front End
Regeneration	Supported
Harmonic Reduction	Active front-end / low-harmonic architecture
Common DC Bus	Supported
Motor Control	Performed by downstream inverter sections
Typical System	Multi-drive common DC bus
Approximate Heat Dissipation	About 51.6 kW at the referenced light-duty operating condition
Typical Environment	Clean industrial indoor electrical room
Mounting Orientation	Vertical floor-mounted cabinet
Service Requirement	Industrial high-voltage maintenance procedures
Typical Power Level	Approximately 1.9 MW
Approximate Weight	About 1,300–1,600 kg class, configuration dependent
Approximate Cabinet Width	About 2,600 mm class
Approximate Cabinet Depth	About 600 mm class
Approximate Cabinet Height	About 2,000 mm class

The dimensions and weight above should be treated as planning-level approximate values, rather than shipment-certified dimensions. Large PowerFlex 755TM equipment is assembled from multiple sections, and the actual overall width and shipping weight can change according to wire bays, enclosure options, control arrangements, bus configuration and other selected hardware.

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Electrical Characteristics

The 20J1F3F1K8LNDNNNNN is designed for a 690 V AC three-phase industrial supply.

Its F1K8 rating corresponds to a Frame 11 bus-supply configuration. At Normal Duty, the DC output rating is approximately 1,914 kW / 1,914 A.

The DC side operates in the approximately 1000 V DC class, which makes this equipment suitable for very high-power common-bus drive installations.

Electrical Parameter	Approximate Value
Model	20J1F3F1K8LNDNNNNN
AC Input Voltage	690 V AC
AC Input	3 Phase
AC Frequency	50 Hz class
DC Output Voltage	1000 V DC class
Normal Duty DC Power	1,914 kW
Normal Duty DC Current	1,914 A
Heavy Duty DC Power	1,500 kW
Heavy Duty DC Current	1,576 A
Internal DC Bus Capacitance	Approximately 31,000 µF
Maximum External DC Bus Capacitance	Approximately 137,134 µF
Power Conversion	Active Front End
Regeneration	Available
Line-Side Conversion	Active controlled rectification
DC Bus Application	Multiple inverter sections

The large current rating is one of the most important characteristics of this product. At this power level, cable selection, busbar design, short-circuit protection, grounding, thermal management and mechanical installation become major engineering considerations.

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Active Front End and Regenerative Operation

One of the main characteristics of the PowerFlex 755TM bus-supply architecture is its Active Front End, commonly abbreviated as AFE.

A conventional diode rectifier generally converts AC into DC in one direction. An AFE can actively control the power exchange between the AC system and the DC bus.

That becomes particularly useful when the connected motors operate in regenerative conditions.

For example, a large hoist may lower a heavy load. During that period, the motor can act as a generator. The regenerated energy can be transferred back through the common DC bus and, where the system configuration permits, returned to the AC supply rather than being dissipated entirely as heat.

The same principle can be useful on large conveyors, cranes, elevators, test equipment, rolling machinery and other applications with frequent acceleration and deceleration.

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Common DC Bus Architecture

The 20J1F3F1K8LNDNNNNN is best understood as the power source for a larger drive system, rather than as an ordinary standalone motor drive.

A typical arrangement can be represented conceptually as:

690 V AC Supply → 20J1F3F1K8LNDNNNNN → Common DC Bus → Multiple Inverter Sections → Motors

This arrangement allows several inverter sections to use the same centralized DC power source.

That can be especially useful where multiple motors operate as part of one machine.

For example, a large material-handling machine may have several motors that need to accelerate together, while another motor is simultaneously decelerating. With a common DC bus, the energy relationships between those drive sections can be managed within the overall system architecture.

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Physical Dimensions and Weight

Because this is a high-power Frame 11 cabinet product, it should be considered a large floor-mounted industrial electrical system rather than a compact cabinet drive.

A typical Frame 11 arrangement uses an approximately 1000 mm input section together with approximately 800 mm power-bay sections. The basic equipment arrangement therefore occupies several metres of cabinet width when fully configured.

Mechanical Parameter	Approximate Value
Model	20J1F3F1K8LNDNNNNN
Frame Size	Frame 11
Approximate Overall Width	2,600 mm class
Approximate Depth	600 mm class
Approximate Height	2,000 mm class
Approximate Footprint	About 1.56 m² class
Approximate Equipment Weight	1,300–1,600 kg class
Shipping Weight	Higher than equipment-only weight
Installation Type	Floor standing
Cabinet Arrangement	Multi-section
Service Access	Front service access required
Lifting Requirement	Heavy industrial lifting equipment

The exact dimensions should be confirmed before preparing a foundation, transport route, lifting plan or electrical-room layout.

The weight is particularly important because this is not equipment that should be handled using ordinary pallet-moving equipment. A proper lifting and positioning plan is normally required.

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Cooling and Thermal Management

At approximately 1.9 MW of rated power, thermal management is a major part of the installation.

The unit uses forced-air cooling. The power modules, filters and other electrical components generate heat during operation, and this heat has to be removed continuously.

The approximate loss figure for the 20J F1K8 bus-supply rating is around 51.6 kW under the referenced full-load operating condition.

That is a substantial amount of heat.

For an electrical room, this means ventilation and air-conditioning calculations should not be based only on the motor load. The heat produced by the drive system itself must also be included.

Thermal Parameter	Approximate Value
Model	20J1F3F1K8LNDNNNNN
Cooling	Forced Air
Approximate Full-Load Loss	51.6 kW class
Cooling Requirement	High
Installation Environment	Clean, ventilated electrical room
Airflow	Must be maintained according to the complete cabinet configuration
Ambient Temperature	Derating may apply above rated conditions
Maintenance	Cooling fans and airflow paths require inspection

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Product Advantages

1. Very High Power Capacity

The most obvious advantage of this model is its large power capability.

With a Normal Duty rating around 1.914 MW, it is suitable for industrial machinery where conventional low-voltage standalone drives are no longer practical as the primary system architecture.

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2. Centralized DC Bus

The common DC bus structure allows several inverter sections to be supplied from one centralized power-conversion system.

This can simplify the electrical architecture of a large multi-motor machine.

Instead of giving every motor inverter its own complete AC input stage, the common bus approach allows the AC-to-DC conversion to be centralized.

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3. Regenerative Energy Handling

The AFE arrangement provides a practical way to manage regenerative energy.

In applications with frequent braking, lowering or deceleration, this can be much more useful than simply converting regenerative energy into heat through braking resistors.

The actual energy flow depends on the system configuration and operating conditions.

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4. Low-Harmonic Operation

The active front-end design is intended to provide improved control of the input current waveform compared with a basic uncontrolled rectifier.

This can be valuable in large installations where electrical-system power quality is an important engineering consideration.

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5. Suitable for Multi-Motor Machinery

The PowerFlex 755TM architecture is particularly well suited to machinery with multiple motors.

The centralized bus allows several inverter sections to operate from the same DC power system, making it possible to design coordinated multi-axis equipment around a common electrical architecture.

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6. High-Voltage 690 V Platform

The 690 V AC class is common in large industrial equipment because increasing voltage allows high power to be transmitted at lower current than would be required at lower voltage levels.

For a megawatt-scale system, this can have a significant impact on cable, busbar and switchgear design.

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7. Modular System Concept

The PowerFlex 755TM system uses a modular approach.

This is useful for large machines because the system can be built around separate bus-supply, inverter, control and associated power components.

For engineering teams, a modular architecture can also make large systems easier to organize during design and commissioning.

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Typical Applications

Mining Equipment

Large mining machines often contain multiple high-power motors.

Conveyors, crushers, hoists, mills and material-handling equipment can require very large amounts of electrical power, making a high-power common DC bus architecture useful.

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Conveyor Systems

Long conveyors may use several drive motors distributed along the conveyor.

A centralized DC bus can provide a common power architecture for these drive sections.

Regenerative operation can also become relevant when conveying material downhill or during controlled deceleration.

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Cranes and Hoists

Cranes and hoists are particularly suitable for regenerative drive technology.

During lowering operations, the motor can generate electrical energy. An AFE-based system can provide a controlled path for handling that energy.

The 20J1F3F1K8LNDNNNNN can therefore be considered for very large crane and hoisting systems where the total motor power reaches the megawatt range.

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Steel and Metal Processing

Steel mills and other metal-processing equipment often contain several large motors working together.

Rolling equipment, processing lines, conveyors and other large machine sections can benefit from a common DC bus arrangement.

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Large Material-Handling Systems

Large material-handling systems may use multiple motors with different operating cycles.

The common-bus concept can provide a centralized power source for the inverter sections controlling those motors.

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Large Process Machinery

Some continuous-process machines require several high-power motors to operate in a coordinated manner.

In these systems, a common DC bus can provide a practical way of organizing the drive power system.

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Test Stands and High-Power Machinery

Industrial test systems may require repeated acceleration, deceleration and regeneration.

An AFE bus supply can be useful where the energy flow changes frequently and the system needs to handle regenerative operation.

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Application Characteristics

Application	Typical Requirement	Suitability
Mining Conveyor	Very high motor power, multi-drive	High-power common bus architecture
Crane / Hoist	Regeneration and high torque	AFE bus supply architecture
Steel Mill	Multiple large motors	Common DC bus
Rolling Equipment	Rapid acceleration/deceleration	Regenerative architecture
Large Material Handling	Multiple coordinated drives	Centralized DC supply
Process Machinery	Continuous operation	High-power drive system
Large Test Stand	Four-quadrant energy flow	Regenerative system
Heavy Industrial Machine	Megawatt-class power	Frame 11 architecture

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Installation Considerations

The installation of a 690 V, approximately 1.9 MW bus supply requires considerably more planning than a conventional small drive.

The incoming power system needs to be sized for the electrical characteristics of the complete installation.

The DC bus system also needs careful engineering because the operating voltage can reach the 1000 V DC class.

Cable and busbar clearances, grounding, short-circuit protection, ventilation, cabinet spacing, maintenance access and emergency isolation should all be considered during system design.

The electrical room should also be able to handle the heat produced by the drive equipment.

Installation Item	Requirement / Consideration
Model	20J1F3F1K8LNDNNNNN
Input System	690 V AC, 3 Phase
DC Bus	1000 V DC class
Mounting	Floor mounted
Cabinet	Large multi-section cabinet
Cooling	Forced air
Environment	Clean and dry industrial area
Ventilation	High-capacity ventilation required
Grounding	Industrial grounding system required
Service Clearance	Front and equipment-specific service clearance
Lifting	Heavy equipment lifting arrangement
Foundation	Suitable for high equipment weight
Electrical Protection	Must be designed for complete system
Cable Routing	High-current industrial cable/busbar arrangement
Commissioning	Qualified high-voltage personnel

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Important Selection Considerations

The 20J1F3F1K8LNDNNN is not selected only according to motor horsepower.

A proper selection should consider:

• AC supply voltage.
• Frequency.
• Required Normal Duty power.
• Heavy Duty requirements.
• DC bus voltage.
• Number of inverter sections.
• Total connected motor power.
• Regenerative energy.
• Ambient temperature.
• Installation altitude.
• Enclosure type.
• Cooling arrangement.
• Harmonic requirements.
• Short-circuit characteristics.
• DC bus capacitance.
• Cable and busbar arrangement.
• Required protection equipment.
• Mechanical cabinet space.
• Service and maintenance access.

For a system of this size, the complete drive-system configuration is more important than the bus-supply catalog number by itself.

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Five Related Models in the Same Series

The following models are closely related to the 20J1F3F1K8LNDNNN and use the same general 690 V PowerFlex 755TM bus-supply architecture.

The rating increases as the F1K4, F1K8, F2K3, F2K7 and F3K6 configurations move into larger frame sizes.

Model	Series	Voltage	Normal Duty Power	DC Current Class	Frame	Cooling	Enclosure	Approx. Dimensions	Approx. Weight
20J1F3F1K4LNDNNNNN	PowerFlex 755TM	690 V AC	1,456 kW	1,456 A	10	Forced air	IP21 / Type 1	Approx. 2,000 × 600 × 2,000 mm	Approx. 1,000–1,300 kg
20J1F3F1K8LNDNNNNN	PowerFlex 755TM	690 V AC	1,914 kW	1,914 A	11	Forced air	IP21 / Type 1	Approx. 2,600 × 600 × 2,000 mm	Approx. 1,300–1,600 kg
20J1F3F2K3LNDNNNNN	PowerFlex 755TM	690 V AC	2,379 kW	2,379 A	12	Forced air	IP21 / Type 1	Approx. 2,600–3,000 × 600 × 2,000 mm	Approx. 1,600–2,000 kg
20J1F3F2K7LNDNNNNN	PowerFlex 755TM	690 V AC	2,849 kW	2,849 A	13	Forced air	IP21 / Type 1	Approx. 2,600–3,000 × 600 × 2,000 mm	Approx. 2,000–2,500 kg
20J1F3F3K6LNDNNNNN	PowerFlex 755TM	690 V AC	3,781 kW	3,781 A	14	Forced air	IP21 / Type 1	Approx. 2,600–3,500 × 600 × 2,000 mm	Approx. 2,500–3,500 kg

The figures in the dimensions and weight columns are engineering-level estimates intended for product comparison and planning. The actual cabinet arrangement can vary depending on enclosure options, wire bays, bus configuration and other selected options.

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Comparison of the Related 690 V Models

Model	Normal Duty Power	Frame	Relative Power Level	Typical Use
20J1F3F1K4LNDNNNNN	1,456 kW	10	High	Large industrial machinery
20J1F3F1K8LNDNNNNN	1,914 kW	11	Very High	Large multi-drive systems
20J1F3F2K3LNDNNNNN	2,379 kW	12	Very High	Heavy industrial machinery
20J1F3F2K7LNDNNNNN	2,849 kW	13	Extremely High	Large mining and processing systems
20J1F3F3K6LNDNNNNN	3,781 kW	14	Multi-MW	Very large industrial systems

The 20J1F3F1K8LNDNNNNN sits in the middle of this group, making it a substantial Frame 11 system without moving into the larger Frame 12–14 cabinet classes.

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Five Representative Allen-Bradley Models from the Same Brand Portfolio

The following models are representative Allen-Bradley PowerFlex products from different product families. They are not direct substitutes for the 20J1F3F1K8LNDNNNNN.

The smaller products are intended for individual motor applications, while the 20J PowerFlex 755TM model is intended for a high-power common-bus architecture.

Model	Product Family	Voltage Class	Typical Power / Current Class	Cooling	Approx. Dimensions	Approx. Weight
25B-D2P3N104	PowerFlex 525	400/480 V class	Small motor-drive class, approx. 2.3 A	Air cooled	Approx. 90 × 180 × 180 mm	Approx. 2–3 kg
25B-D017N104	PowerFlex 525	400/480 V class	Approx. 7.5 A class	Air cooled	Approx. 130 × 220 × 180 mm	Approx. 4–6 kg
20F1AGF012JN0NNNNN	PowerFlex 753	690 V class	Approx. 7.5 kW class	Air cooled	Approx. 665 × 308 × 346 mm	Approx. 39 kg
20F1AGF020JN0NNNNN	PowerFlex 753	690 V class	Approx. 15 kW class	Air cooled	Approx. 665 × 308 × 346 mm	Approx. 39 kg
20J1F3F1K8LNDNNNNN	PowerFlex 755TM	690 V class	1,914 kW / 1,914 A	Forced air	Approx. 2,600 × 600 × 2,000 mm class	Approx. 1,300–1,600 kg

These products cover a very wide range of applications, from small standalone motor control through large common-bus industrial systems.

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Why the 20J1F3F1K8LNDNNNNN Is Different from a Conventional VFD

A normal VFD generally has an AC input, rectifier, DC link, inverter and motor output contained within one drive system.

The 20J1F3F1K8LNDNNNNN has a different role.

It primarily functions as the high-power AC-to-DC bus supply for a larger PowerFlex 755TM system.

That means the motor inverters can be installed separately on the common DC bus.

This is particularly useful when one machine contains several large motors.

The bus-supply approach can reduce duplication of AC input power-conversion components and gives the system designer greater freedom in arranging multiple inverter sections.

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Energy Management Advantages

One of the most useful characteristics of a common DC bus system is the ability to manage energy between different drive sections.

Imagine a machine with several motors.

One motor may be accelerating.

A second motor may be running at constant speed.

A third motor may be decelerating.

During deceleration, the third motor can return energy to the DC bus.

That energy may then be available to other parts of the system or can be managed through the regenerative front end.

This type of energy interaction is one of the main reasons common DC bus systems are attractive for large machines with frequent changes in speed and load.

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Harmonic and Power-Quality Considerations

Large conventional rectifier systems can create substantial harmonic currents.

At the megawatt scale, the resulting electrical-system impact becomes much more significant.

The AFE architecture of the PowerFlex 755TM family is designed to provide controlled line-side current and lower-harmonic operation compared with a basic uncontrolled rectifier arrangement.

This does not mean that every installation automatically meets every site-specific harmonic requirement.

The complete electrical system still needs to be evaluated, particularly where the installation has strict power-quality requirements.

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Maintenance Considerations

Because the 20J1F3F1K8LNDNNNNN is a large high-power system, maintenance should be approached as part of the overall electrical-system design.

Cooling fans are important components because airflow directly affects the thermal condition of the power modules.

The cabinet should be kept clean and free from excessive dust, oil mist and other contaminants.

Connections, busbars, power modules, cooling passages and control wiring should be inspected according to the maintenance program for the complete installation.

The DC bus also requires special attention because potentially hazardous DC voltage can remain present after AC input power has been disconnected until the required discharge procedure has been completed.

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Product Advantages at a Glance

Advantage	Description
High Power	Approximately 1.9 MW Normal Duty rating
690 V Platform	Designed for large industrial electrical systems
Frame 11	Large-capacity industrial power architecture
AFE Technology	Active control of AC/DC power conversion
Regenerative Operation	Supports energy recovery in suitable systems
Low-Harmonic Design	Better input-current control than a basic diode rectifier
Common DC Bus	Multiple inverter sections can share the DC bus
Multi-Motor Capability	Suitable for large coordinated machines
Centralized Power Conversion	Reduces duplication of AC input stages
Modular Architecture	Allows large drive systems to be configured from multiple sections
Industrial Construction	Designed for demanding high-power applications
Scalable Family	Related ratings are available in larger and smaller frames

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Recommended Application Profile

The 20J1F3F1K8LNDNNNNN is generally appropriate when the application has several of the following characteristics:

• Motor power in the megawatt range.
• 690 V AC industrial power supply.
• Multiple inverter sections.
• Common DC bus architecture.
• Frequent acceleration and deceleration.
• Significant regenerative energy.
• Large conveyor systems.
• Mining machinery.
• Crane and hoist systems.
• Steel-processing machinery.
• Large material-handling systems.
• High-power process equipment.
• Multi-axis industrial machines.
• Large test and energy-recovery systems.

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Summary Specification Table

Item	Specification
Model	20J1F3F1K8LNDNNNNN
Brand	Allen-Bradley
Series	PowerFlex 755TM
Product Family	PowerFlex 755T
Product Type	AFE Bus Supply
Voltage	690 V AC
Phase	3 Phase
DC Voltage Class	1000 V DC
Normal Duty Power	1,914 kW
Normal Duty Current	1,914 A
Heavy Duty Power	1,500 kW
Heavy Duty Current	1,576 A
Frame	11
Cooling	Forced Air
Enclosure	IP21 / UL Type 1 class
Mounting	Floor Mount
Regenerative	Yes
AFE	Yes
Common DC Bus	Yes
Low Harmonic	Yes
Approx. Width	2,600 mm class
Approx. Depth	600 mm class
Approx. Height	2,000 mm class
Approx. Weight	1,300–1,600 kg class
Approx. Heat Loss	51.6 kW class
Main Application	Large industrial common-bus drive systems
Typical Motor System	Multi-motor / multi-inverter
Power Level	Approximately 1.9 MW

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Final Product Description

The Allen-Bradley 20J1F3F1K8LNDNNNNN is a high-capacity PowerFlex 755TM 690 V AC regenerative AFE bus supply intended for large industrial common-DC-bus drive systems.

With a Normal Duty rating of approximately 1,914 kW and 1,914 A, this Frame 11 product is designed for applications where several high-power inverter sections need to operate from a centralized DC bus.

Its active front-end architecture provides controlled AC/DC power conversion and supports regenerative operation, making the product suitable for machines where energy can flow in both directions during acceleration, normal operation and braking.

The common DC bus architecture is particularly useful in large multi-motor machines. Instead of treating every motor drive as a completely independent AC-fed unit, the system can centralize the power-conversion stage and distribute DC power to multiple inverter sections.

This approach can be useful in mining, steel processing, large conveyors, cranes, hoists, material handling, large process machinery and other high-power industrial applications.

The 690 V AC input and approximately 1000 V DC bus class make the equipment suitable for megawatt-level industrial systems, while the Frame 11 construction provides the physical and electrical capacity needed for this power range.

The product is physically large and heavy compared with ordinary variable-frequency drives. A complete installation can occupy several metres of cabinet width and require dedicated floor space, forced-air cooling, high-current bus or cable connections, appropriate electrical protection and professional lifting and installation arrangements.

For engineering, replacement or purchasing purposes, the complete catalog number 20J1F3F1K8LNDNNNNN should be matched carefully with the existing nameplate and system configuration. The suffix options can affect the final equipment arrangement, so a visually similar unit should not automatically be treated as a direct replacement.

Overall, this model belongs to the high-power end of the PowerFlex 755TM platform and is best viewed as a central power-conversion component for a large industrial multi-drive system, rather than as a conventional standalone motor inverter.