Mersen A070UD32TTI900 Protistor Fuse, 900A 700V AC, Size 32 aR, High-Speed Square Body with Striker - Pack of 3

The Mersen Protistor® A070UD32TTI900 (Item Number S300442) is a high-capacity, ultra-fast acting square body fuse-link specifically engineered for the protection of power semiconductor devices. This Size 32 aR class fuse is designed for heavy-duty industrial environments, protecting critical power electronics such as high-current rectifiers, large-scale inverters, and industrial UPS systems. It provides exceptional short-circuit protection by minimizing I²t let-through energy, preventing catastrophic damage to sensitive components like diodes, thyristors, and IGBTs.

Constructed with a high-grade ceramic body and silver-plated copper mounting terminals, the fuse ensures low power loss and high thermal stability. The internal silver elements are embedded in high-purity quartz sand to guarantee rapid arc extinction and a very high breaking capacity of 200kA. This model features an integrated Type I mechanical striker, which provides local visual indication of a blown fuse and can be used to trigger auxiliary microswitches for remote monitoring. The TTI flush-end M10 metric threaded interface allows for robust, low-impedance connection to electrical busbars.

Technical Specifications

• Manufacturer: Mersen
• Catalog Number: A070UD32TTI900
• Item Number: S300442
• Amperage Rating: 900A
• 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: Flush-End M10 Metric Threads (TTI)
• Indication System: Integrated Mechanical Striker (Type I)
• Pre-arcing I²t: 210 kA²s
• Total Clearing I²t at Rated Voltage: 1450 kA²s
• Power Dissipation at Rated Current: 155W
• Standards Compliance: IEC 60269-4, UL Recognized, RoHS Compliant
• Quantity: Pack of 3