Mersen A070UD32TTI550 Protistor Fuse, 550A 700V AC, Size 32 aR, High-Speed Square Body with Striker - Pack of 3

The Mersen Protistor® A070UD32TTI550 (Item Number N300438) is a high-performance ultra-fast acting square body fuse-link designed for the protection of power semiconductor devices. This Size 32 aR class fuse is specifically engineered to provide superior short-circuit protection for high-power electronics such as rectifiers, inverters, and large motor drives. It is optimized to minimize I²t let-through energy, ensuring the protection of sensitive components like diodes, thyristors, and SCRs during fault conditions.

Constructed with a premium ceramic body and silver-plated contact surfaces, this fuse ensures high breaking capacity and exceptional thermal stability. The internal silver elements are embedded in high-purity solidified sand to effectively quench arcs. This model features an integrated Type I mechanical striker, allowing for local visual trip indication or the triggering of a microswitch for remote fault signaling. The TTI flush-end M10 threaded interface ensures a low-inductance, secure bolted mounting directly to electrical busbars.

Technical Specifications

• Manufacturer: Mersen
• Catalog Number: A070UD32TTI550
• Item Number: N300438
• Amperage Rating: 550A
• 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: 45 kA²s
• Total Clearing I²t at Rated Voltage: 315 kA²s
• Power Dissipation at Rated Current: 105W
• Standards Compliance: IEC 60269-4, UL Recognized, RoHS Compliant
• Quantity: Pack of 3