Mersen A070UD32LI400 Protistor Fuse, 400A 700V AC, Size 32 aR, High-Speed Square Body with LI Bolted Contacts - Pack of 3

The Mersen Protistor® A070UD32LI400 (Item Number Y219776) is a high-capacity, ultra-fast acting square body fuse-link designed for the comprehensive protection of power semiconductor devices. With a rated current of 400A and a voltage rating of 700V AC, this Size 32 aR class fuse is specifically engineered for critical industrial power electronics, including large-scale rectifiers, high-power converters, and AC/DC motor drives. It offers exceptional current limitation and provides very low I²t (clearance energy) values, ensuring instantaneous protection for sensitive components like thyristors, GTOs, and IGBTs under short-circuit conditions.

Constructed with a premium ceramic body and silver-plated copper LI-style (Bolted Blade) contacts, the A070UD32LI400 ensures high electrical conductivity and superior thermal stability. Its internal silver elements and high-purity silica sand filling are optimized for rapid arc quenching, enabling a massive breaking capacity of 200kA. This fuse includes an integrated Type K mechanical striker for visual indication of operation, which can also be interfaced with auxiliary microswitches for remote system signaling.

Technical Specifications

• Manufacturer: Mersen
• Catalog Number: A070UD32LI400
• Item Number: Y219776
• Amperage Rating: 400A
• Voltage Rating: 700V AC (IEC / UL)
• Interrupting Rating (Breaking Capacity): 200kA at 700V AC
• Operating Class: aR (Ultra-Fast Acting)
• Product Size: 32
• Mounting Configuration: LI (Bolted Blades)
• Indication System: Integrated Mechanical Striker (K-Type)
• Pre-arcing I²t: 21 kA²s
• Total Clearing I²t at Rated Voltage: 140 kA²s
• Power Dissipation at Rated Current: 70W
• Standards Compliance: IEC 60269-4, UL 248-13 Recognized, RoHS Compliant
• Quantity: Pack of 3