Mersen A4J250 Class J Fast-Acting Fuse – 250A – 600VAC/300VDC – Amp-Trap® Blade Fuse

The Mersen A4J250 is an Amp-Trap® Class J fast-acting fuse designed for high-performance protection in industrial and commercial electrical distribution systems. Rated at 250 Amps, this current-limiting fuse provides rapid interruption of fault currents to protect sensitive equipment and downstream circuits. With voltage ratings of 600VAC and 300VDC, it is suitable for use in Class J fuse applications requiring compact size, high interrupting capacity, and fast response to short-circuit conditions.

Voltage and Rating

• Current Rating: 250 Amps
• Voltage Rating: 600VAC / 300VDC
• Frequency: 50/60 Hz
• Fuse Class: Class J
• Fuse Type: Fast-Acting, Current-Limiting

Key Specifications

• Product Type: Industrial Power Fuse
• Series: Amp-Trap® A4J
• Part Number: A4J250
• Manufacturer: Mersen / Ferraz Shawmut
• Mounting Style: Blade
• Response Type: Fast-Acting (non-time-delay)
• Current Limiting: Yes

Technical Specifications

• Protection Type: Overcurrent and short-circuit protection (fast interruption)
• Application Suitability: Feeders, branch circuits, control panels, MCCs, and industrial distribution systems
• Coordination Type: Supports selective coordination in Class J systems
• Construction Features: Compact design, high interrupting capacity, low let-through energy
• System Integration: Suitable for modern high-density electrical panel layouts

Standards and Approvals

• UL Listed
• CSA Certified
• Compliant with Class J fuse requirements

Product Data

• Manufacturer: Mersen / Ferraz Shawmut
• Series: Amp-Trap® A4J
• Part Number: A4J250
• EAN/UPC: 782001960391

Applications

• Industrial power distribution systems
• Branch circuit protection
• Feeder protection systems
• Motor control centers (MCCs)
• Control panels and switchboards
• Commercial electrical installations
• Equipment protection in high fault current environments

Returns are easy

You may return items within 30 days of delivery for a refund.

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