Mersen A070UD32LI450 Protistor Fuse, 450A 700V AC, Size 32 aR, High-Speed Square Body with LI Bolted Contacts - Pack of 3

The Mersen Protistor® A070UD32LI450 (Item Number Z219777) is an ultra-fast acting high-speed square body fuse-link designed for the protection of power semiconductor devices. With a rated current of 450A and a voltage rating of 700V AC, this Size 32 aR class fuse is engineered for heavy-duty industrial applications such as semiconductor rectifiers, traction inverters, and high-capacity UPS systems. It provides superior peak current limitation and very low let-through energy (I²t), ensuring rapid isolation of faults to protect sensitive electronics like thyristors and power transistors.

Built with a high-grade ceramic body and silver-plated copper LI-style (Bolted Blade) contacts, the A070UD32LI450 ensures minimized power loss and high reliability during continuous operation. The fuse utilizes pure silver elements and high-purity silica sand to achieve efficient arc quenching and a high breaking capacity of 200kA. This model features an integrated Type K mechanical striker, offering clear visual indication and the capability to actuate an external microswitch for remote fault monitoring.

Technical Specifications

• Manufacturer: Mersen
• Catalog Number: A070UD32LI450
• Item Number: Z219777
• Amperage Rating: 450A
• 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: 31 kA²s
• Total Clearing I²t at Rated Voltage: 210 kA²s
• Power Dissipation at Rated Current: 76W
• Standards Compliance: IEC 60269-4, UL 248-13 Recognized, RoHS Compliant
• Quantity: Pack of 3