Merlin Gerin Masterpact NW50 H1 5000A Circuit Breaker

The Merlin Gerin Masterpact NW50 H1 Circuit Breaker with Micrologic 2.0A Trip Unit represents the gold standard in high-current electrical protection. Designed and manufactured by Merlin Gerin, now part of Schneider Electric, this Masterpact series air circuit breaker delivers an extraordinary 5000A current rating with Category B breaking capacity. When your facility demands the highest level of protection for critical electrical infrastructure, the NW50 H1 provides the reliability, precision, and performance that only decades of circuit breaker innovation can deliver.

At Aeliya Marine, we specialize in sourcing premium industrial electrical equipment for demanding applications. The Masterpact NW series has been the circuit breaker of choice for facilities worldwide where electrical reliability is mission-critical. From data centers to shipyards, steel mills to offshore platforms, the NW50 H1 provides the robust overcurrent and short-circuit protection that keeps operations running safely. The integrated Micrologic 2.0A trip unit adds advanced metering, communication, and selective coordination capabilities that elevate this breaker beyond basic protection devices.

Technical Specifications

Applications & Use Cases

The Merlin Gerin Masterpact NW50 H1 circuit breaker is engineered for the most critical and demanding electrical distribution applications. Its 5000A rating and 100kA short-time withstand capacity make it suitable for protecting the largest electrical systems.

• Primary Switchboards: Main incoming protection for large industrial and commercial electrical installations
• Data Centers: Critical power distribution protection for mission-critical IT infrastructure
• Marine Electrical: Main switchboard protection for large vessels and offshore platforms
• Steel Mills: Protection for large furnace transformers and distribution systems
• Petrochemical: Primary protection for refinery and chemical plant electrical systems
• Power Generation: Protection for generator outputs and station service systems
• Infrastructure: Metro, airport, and hospital main electrical protection

Why Choose the Merlin Gerin Masterpact NW50 H1

Merlin Gerin's Masterpact series has been the benchmark for air circuit breaker performance since its introduction. The NW50 H1 with Micrologic 2.0A trip unit represents the culmination of decades of circuit breaker innovation, offering features and performance that generic alternatives cannot match. The Micrologic 2.0A trip unit provides comprehensive protection functions including long-time, short-time, and instantaneous overcurrent protection, along with ground fault protection and advanced metering capabilities.

The Category B rating (100kA/1s) means this breaker can withstand a full short-circuit current for up to one second without tripping, enabling selective coordination with downstream protection devices. This is critical in large facilities where unnecessary tripping of main breakers can cause widespread outages. The 100% Ics rating ensures the breaker can safely interrupt its full rated short-circuit current and immediately be returned to service.

Micrologic 2.0A Trip Unit Features

The Micrologic 2.0A electronic trip unit transforms the NW50 H1 from a simple protective device into an intelligent power management tool. Features include adjustable long-time and short-time protection settings, instantaneous overcurrent protection, ground fault protection, true RMS current metering, and communication capability for integration with building management and SCADA systems. The digital display provides real-time current readings and trip event logging for maintenance diagnostics.

Compatibility & Integration

The Masterpact NW50 H1 is designed for integration into Schneider Electric's comprehensive electrical distribution ecosystem. It can be equipped with a wide range of accessories and communication modules to meet specific application requirements.

• Mounting: Fixed and drawout versions available for different switchboard designs
• Accessories: Shunt trips, undervoltage releases, auxiliary contacts, and mechanical interlocks
• Communication: Optional Modbus, BACnet, or Ethernet adapters for BMS/SCADA integration
• Busbars: Compatible with standard Masterpact horizontal and vertical busbar connections
• Enclosures: Fits standard Masterpact switchboard configurations

Maintenance & Support

Aeliya Marine inspects and tests every Masterpact circuit breaker before listing. Our technicians verify contact condition, mechanism operation, trip unit functionality, and insulation integrity to ensure the breaker meets factory specifications. We provide the technical documentation needed for proper installation, commissioning, and maintenance.

Your purchase is protected by our 30-day warranty and includes free worldwide shipping. Our technical team can assist with breaker selection, coordination studies, installation guidance, and troubleshooting.

Frequently Asked Questions

Q1: What is the current rating of the NW50 H1?

The NW50 H1 is rated for 5000A continuous current, making it suitable for the largest electrical distribution systems.

Q2: What does the Micrologic 2.0A trip unit provide?

The Micrologic 2.0A provides advanced protection functions, current metering, and communication capabilities beyond basic thermal-magnetic trip units.

Q3: What is the short-circuit rating?

The breaker has a 100kA/1s short-time withstand rating (Category B) and Ics = 100% of Icu, meaning it can interrupt its full rated short-circuit current and be immediately reset.

Q4: What standards does this breaker meet?

The NW50 H1 meets IEC 60947-2, the international standard for low-voltage circuit breakers.

Q5: Is this breaker suitable for marine applications?

Yes, the Masterpact NW series is widely used in marine switchboards. The 1000V insulation rating and robust construction make it suitable for shipboard electrical systems.

Q6: What warranty is included?

Aeliya Marine provides a 30-day warranty on this used breaker, along with free worldwide shipping.

Q7: Can the trip unit be upgraded?

Yes, Micrologic trip units can often be upgraded or replaced with newer versions to add functionality. Contact our team for upgrade options.

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