Product Overview

The Schneider Electric NW20N2 MasterPact NW Circuit Breaker is a heavy-duty low-voltage air circuit breaker designed for power distribution and electrical protection in industrial and commercial installations. It belongs to the MasterPact NW product family, which is used in main distribution switchboards, large electrical panels, and critical power systems.

Large industrial electrical networks require reliable protection against overloads, short circuits, and abnormal operating conditions. A circuit breaker provides a controlled method of interrupting electrical current when a fault occurs, helping protect electrical equipment, cables, and downstream distribution circuits.

The NW20N2 is associated with the NW20 frame, which has a rated current class of 2000 A. Its substantial frame size makes it suitable for applications involving high-current power distribution. Depending on the selected configuration, MasterPact NW circuit breakers can be installed as fixed or drawout devices and can be equipped with different trip units, operating mechanisms, and electrical accessories.

The model is intended for use in industrial power distribution systems where reliable circuit isolation and fault interruption are essential. Typical applications include manufacturing plants, commercial buildings, utility distribution rooms, data centers, and large electrical substations.

The supplied dimensions are 352 × 537 × 297 mm, with a listed weight of 65 kg. These values correspond to the approximate dimensions and weight of a fixed four-pole NW20 configuration. Actual specifications should be confirmed against the complete product configuration before installation or replacement.

Technical Specifications

Note: NW20 identifies the 2000 A frame class. The exact rated voltage, short-circuit performance, trip unit, and operating accessories must be verified from the complete nameplate and product documentation.

Function and Working Principle

The Schneider NW20N2 is designed to control and protect high-current electrical distribution circuits. It operates by allowing current to flow under normal conditions and opening its contacts when a qualifying fault or protection command occurs.

1. Normal Current Distribution

During normal operation, the circuit breaker’s main contacts remain closed, allowing electrical current to pass from the incoming power supply to the downstream distribution system.

In an industrial installation, the breaker may supply large electrical loads such as production machinery, motor control centers, transformers, and auxiliary distribution panels.

The 2000 A frame class makes the NW20 family suitable for high-current distribution applications when the selected configuration is correctly matched to the system.

2. Overload Protection

An overload occurs when a circuit carries more current than its permitted operating level for an extended period.

When equipped with a suitable electronic trip unit, the circuit breaker can monitor current and initiate a trip when the configured protection conditions are exceeded.

Overload protection helps prevent excessive heating in conductors and connected electrical equipment. The trip settings must be coordinated with cable ratings, load characteristics, and the overall protection strategy.

3. Short-Circuit Protection

A short circuit can produce an extremely high fault current within a very short period. If not interrupted correctly, this current can damage electrical equipment and create serious safety hazards.

The MasterPact NW circuit-breaker platform is designed for high-current fault interruption. Its actual short-circuit breaking capacity depends on the specific performance version and rated operating voltage.

The selected breaker must have an adequate interrupting rating for the prospective short-circuit current at the installation point.

4. Circuit Isolation

The breaker can be used to disconnect a distribution circuit for maintenance, inspection, or equipment replacement.

Where the selected version is suitable for isolation, it can form part of the electrical isolation strategy for a distribution system.

Maintenance personnel must still follow the applicable lockout and verification procedures. Opening a circuit breaker alone should not be treated as proof that all hazardous electrical energy has been removed.

5. Trip Unit and Protection Coordination

MasterPact NW circuit breakers can be equipped with different protection and monitoring configurations.

Depending on the installed trip unit, available functions may include long-time overload protection, short-time protection, instantaneous short-circuit protection, and ground-fault protection.

Protection settings must be selected according to the electrical system design. Incorrect settings can result in unnecessary trips or inadequate fault protection.

Role in Industrial Power Distribution Systems

The NW20N2 can serve as a major switching and protection device in a low-voltage distribution network.

Main Incoming Circuit Breaker

In many industrial facilities, a large air circuit breaker is installed at the incoming section of the main switchboard.

It provides a primary means of controlling and protecting the incoming power supply before electricity is distributed to downstream feeders.

Busbar Protection and Distribution

The circuit breaker can be incorporated into a switchboard containing copper or aluminum busbars, feeder breakers, metering equipment, and other distribution components.

The busbar system must be designed to withstand the expected operating current and fault conditions.

Transformer Secondary Protection

A suitably rated MasterPact NW circuit breaker may be used on the low-voltage side of a transformer to protect downstream distribution equipment.

The breaker selection must consider transformer capacity, secondary voltage, available fault current, and protection coordination with upstream devices.

Integration with Monitoring Systems

Depending on the installed trip unit and accessories, MasterPact NW equipment can support electrical monitoring and communication functions.

These functions may allow operators to obtain information about current, protection events, and breaker operating status through an appropriate monitoring architecture.

The communication capabilities depend on the actual installed accessories and should not be assumed from the NW20N2 model designation alone.

Industrial Applications

The Schneider NW20N2 is intended for high-current electrical distribution environments where dependable switching and protection are required.

1. Manufacturing Plants

Large manufacturing facilities use substantial electrical power for production machinery, process equipment, compressed-air systems, pumps, and ventilation.

A 2000 A frame-class air circuit breaker may be used as a main distribution or major feeder protection device in an appropriately engineered switchboard.

2. Data Centers

Data centers require reliable electrical distribution for servers, cooling systems, UPS equipment, and supporting infrastructure.

Air circuit breakers can be used in main distribution and power-switching arrangements. Their selection must account for available fault current, system redundancy, and coordination with upstream and downstream protection devices.

3. Commercial Buildings

Large commercial complexes, office buildings, hospitals, and transportation facilities require high-capacity electrical distribution systems.

A MasterPact NW circuit breaker may be installed in the main low-voltage switchboard to control and protect major distribution circuits.

4. Power Distribution Facilities

Electrical substations and industrial distribution rooms use circuit breakers to manage incoming and outgoing power circuits.

The breaker must be selected according to the system voltage, current requirements, fault level, and applicable electrical standards.

5. Heavy Industrial Equipment

Steel plants, mining operations, chemical processing facilities, and other heavy industries may have large electrical loads that require high-capacity protection.

The NW20 frame class can be considered for suitable distribution applications where the electrical system design requires a 2000 A class breaker.

Installation and System Integration

Correct installation is essential for safe operation and reliable fault interruption.

1. Verify Electrical Ratings

Before installing the NW20N2, confirm the system voltage, rated current, frequency, and prospective short-circuit current.

The 2000 A frame rating should not be confused with the actual trip-unit setting. The protection configuration must be selected according to the connected load and distribution-system requirements.

2. Confirm Installation Configuration

MasterPact NW breakers are available in different mechanical arrangements, including fixed and drawout configurations.

The supplied dimensions of 352 × 537 × 297 mm correspond to the approximate envelope of a fixed four-pole NW20 configuration.

Check the actual breaker and switchboard drawings before preparing mounting supports, busbar connections, or cable terminations.

3. Busbar and Cable Connections

High-current connections require correctly designed conductors, busbars, and termination hardware.

Connection surfaces must be clean and correctly aligned. Tightening torque should follow the manufacturer’s installation instructions.

Improper connections can produce excessive resistance, localized heating, and damage to electrical components.

4. Protection Settings

The trip unit must be configured according to the protection coordination study.

Important considerations include:

• Long-time overload settings.
• Short-time pickup and delay.
• Instantaneous protection.
• Ground-fault protection, where available.
• Coordination with upstream and downstream breakers.
• Cable and busbar thermal limits.

Protection settings should be reviewed by qualified electrical engineers.

5. Control and Auxiliary Wiring

Depending on the selected configuration, the circuit breaker may use auxiliary contacts, shunt-trip accessories, undervoltage releases, motorized operating mechanisms, and other control components.

Before connecting these circuits, verify the accessory catalog numbers, control voltage, terminal assignments, and wiring diagrams.

6. Commissioning and Testing

Before energizing the circuit breaker, inspect the mechanical installation, busbar connections, control wiring, grounding, and operating mechanism.

Commissioning should include appropriate electrical and mechanical checks, trip-unit verification, and functional testing according to the manufacturer’s procedures and applicable standards.

Testing must be performed by qualified personnel using suitable equipment.

Compatible System Components

The NW20N2 is normally installed as part of a complete electrical distribution assembly.

These components are examples of equipment used in a complete installation. Their inclusion depends on the actual circuit-breaker configuration and switchboard design.

Alternative Models and Replacement Considerations

When replacing an NW20N2, the replacement should be selected according to the original electrical and mechanical configuration.

Before ordering a replacement, compare:

• Complete catalog number.
• Rated current and frame size.
• Number of poles.
• Fixed or drawout installation.
• Rated operational voltage.
• Ultimate and service short-circuit breaking capacity.
• Trip-unit type and protection functions.
• Busbar and terminal arrangement.
• Auxiliary contacts and control accessories.
• Overall dimensions and installation clearances.

A replacement with the same frame current rating is not necessarily a direct substitute. Mechanical dimensions, connection arrangements, trip-unit functions, and protection characteristics must all be checked.

Key Advantages

High-Current Distribution Capability

The NW20 frame belongs to the 2000 A current class, making it suitable for appropriately designed high-current distribution systems.

Comprehensive Protection Options

The MasterPact NW platform supports different trip-unit configurations and protection functions, allowing engineers to select protection arrangements according to system requirements.

Industrial Switching Design

The air circuit breaker is designed for demanding low-voltage distribution applications involving large electrical loads.

Configurable Installation Arrangements

The MasterPact NW family offers different mechanical and electrical configurations, including fixed and drawout arrangements.

Integration with Distribution Systems

Depending on the selected accessories, the breaker can be integrated with auxiliary control circuits, monitoring equipment, and switchboard automation systems.

Maintenance and Replacement Support

The established MasterPact NW platform is used in many existing industrial installations, making accurate model identification important for maintenance and spare-parts procurement.

Technical FAQs

1. What is the Schneider NW20N2?

The NW20N2 is a Schneider Electric MasterPact NW series air circuit breaker associated with the NW20, 2000 A frame class. It is designed for high-current low-voltage power distribution and circuit protection.

2. What is the rated current of the NW20 frame?

The NW20 frame has a rated current class of 2000 A. The actual protection setting depends on the installed trip unit and the electrical system design.

3. What is the difference between an air circuit breaker and a miniature circuit breaker?

An air circuit breaker is designed for much larger current ratings and industrial distribution applications. Miniature circuit breakers are generally used for lower-current branch and control circuits.

4. What applications use the NW20N2?

Typical applications include industrial main switchboards, transformer secondary distribution, data centers, large commercial buildings, and power distribution facilities.

5. Does the NW20N2 include an electronic trip unit?

The complete configuration must be checked. MasterPact NW breakers can be supplied with different trip-unit arrangements. Do not assume a particular trip-unit model without confirming the installed unit.

6. Is the NW20N2 available in fixed and drawout versions?

The MasterPact NW family includes both fixed and drawout configurations. The exact mechanical arrangement of the supplied NW20N2 should be verified before purchasing or replacement.

7. What is the breaking capacity of the NW20N2?

The breaking capacity depends on the exact performance designation and rated operating voltage. Check the product nameplate and manufacturer’s technical documentation to identify the applicable Icu, Ics, and Icw ratings.

8. What should be checked before replacing this breaker?

Verify the frame rating, number of poles, mounting arrangement, rated voltage, short-circuit ratings, trip unit, busbar connections, and auxiliary accessories.

9. Can the NW20N2 be integrated into a power monitoring system?

Yes, suitable MasterPact NW configurations can support monitoring and communication functions through compatible trip units and accessories. The required hardware must be confirmed for the specific installation.

10. What are the dimensions and weight of this model?

The supplied listing values are 352 × 537 × 297 mm and 65 kg. These figures correspond to the approximate dimensions and weight of a fixed four-pole NW20 configuration. Confirm the actual unit before shipment or switchboard design.

Procurement and Maintenance Recommendations

When sourcing the Schneider NW20N2, confirm the complete model designation and inspect the product nameplate. The NW20 frame rating alone is not sufficient to establish the full electrical and mechanical configuration.

For replacement projects, verify the number of poles, fixed or drawout arrangement, rated voltage, short-circuit breaking capacity, trip unit, and available accessories. Request clear photographs of the front panel, terminals, nameplate, and operating mechanism.

For used or refurbished circuit breakers, check the mechanical condition, contact wear indicators where provided, operating mechanism, trip unit, auxiliary circuits, and maintenance history. Where the breaker is intended for a critical power system, request suitable inspection and functional test documentation.

Routine maintenance should follow the manufacturer’s instructions and applicable electrical safety requirements. Inspection may include checking connections, operating mechanisms, insulation condition, auxiliary circuits, and trip-unit functions.

Because the breaker is a high-current protective device, installation, testing, and maintenance should be carried out by qualified electrical personnel. Protection settings and replacement decisions should be supported by an appropriate engineering review.

Conclusion

The Schneider Electric NW20N2 MasterPact NW Circuit Breaker is designed for high-current low-voltage power distribution applications. Associated with the 2000 A NW20 frame class, it can be used in industrial switchboards, commercial power distribution systems, and other installations requiring substantial electrical capacity.

Its exact performance depends on the complete breaker configuration, including pole count, mounting arrangement, trip unit, and short-circuit ratings. The supplied dimensions of 352 × 537 × 297 mm and weight of 65 kg are consistent with a fixed four-pole NW20 configuration.

For procurement, maintenance, and replacement projects, verifying the complete catalog designation and electrical ratings is essential to ensure safe operation and compatibility with the existing distribution system.