A4J300 - 300 Amp Fuse

A4J300 - 300 Amp Fuse

Electrical systems don’t leave much room for hesitation when a fault occurs — and that’s exactly why the Mersen A4J300 Amp-Trap® Class J Fast-Acting Fuse is built to respond fast. Designed for demanding commercial and industrial environments, this 300A fuse helps protect your critical equipment from damaging overloads and short circuits before they can lead to expensive downtime, equipment failure, or safety concerns. Whether you’re maintaining a manufacturing facility, servicing HVAC equipment, or managing a power distribution system, the A4J300 delivers the dependable overcurrent protection professionals rely on every day.

Built with durable materials and engineered for consistent performance, the Mersen A4J300 features a rugged GMG insulating body paired with brass alloy blade terminals for secure conductivity and long-term dependability. Its unique Class J design helps prevent incorrect fuse replacement with lower-rated alternatives, adding another layer of protection and helping you support safer maintenance practices. For electrical professionals who need a fuse that combines speed, safety, and trusted protection, the A4J300 is a smart solution for keeping operations running smoothly.

Key Features and Benefits

• Fast-acting protection: Helps respond quickly to overloads and short circuits.
• Current-limiting design: Helps reduce potential damage to electrical equipment.
• High 200 kA interrupting rating: Suitable for demanding industrial applications.
• Class J dimensions: Help prevent improper fuse substitutions.
• Supports both AC and DC electrical systems: Suitable for commercial and industrial applications.
• Blade terminal connection: Allows secure installation and reliable conductivity.
• Durable construction: Designed for long-term performance in commercial and industrial environments.
• Improves system protection: Suitable for motors, transformers, drives, and control panels.
• ROHS compliant: Supports material compliance requirements.
  

Technical Specifications

• Manufacturer: Mersen
  
• Catalog Number: A4J300
  
• Series: Amp-Trap® A4J
  
• Fuse Class: Class J
  
• Fuse Type: Fast-Acting
  
• Ampere Rating: 300A
  
• Voltage Rating: 600VAC / 300VDC
  
• Frequency: 50/60 Hz
  
• Interrupting Rating: 200 kA AC
  
• Current Type: AC/DC
  
• Mounting Type: Clip
  
• Terminal Type: Blade
  
• Terminal Material: Brass Alloy
  
• Body Material: GMG
  
• Product Diameter: 54 mm
  
• Product Length: 181.1 mm
  
• Product Weight: 0.7938 kg
  
• UPC/EAN: 782001960414
  

Material Compliance and Certifications

• ROHS Compliant: Designed to support environmental compliance requirements.
• Low Voltage UL/CSA Applications: Suitable for Low Voltage UL/CSA fuse applications.
• Commercial and industrial electrical protection systems: Manufactured to support dependable overcurrent protection.
  

Where It Works Best

• The Mersen A4J300 Amp-Trap® fuse is an excellent fit for industrial power distribution systems, manufacturing equipment, HVAC systems, motor control centers, branch circuits, and electrical panels where fast and dependable overcurrent protection is essential. It’s especially useful in facilities where protecting sensitive equipment and minimizing unplanned downtime are top priorities.