Mersen A070UD32LI900 Protistor Fuse, 900A 700V AC, Size 32 aR, High-Speed Square Body with LI Bolted Contacts - Pack of 3

The Mersen Protistor® A070UD32LI900 (Item Number H219785) is an ultra-fast acting semi-conductor fuse designed for the high-power protection of industrial electronic systems. With a significant rated current of 900A and a voltage rating of 700V AC, this Size 32 aR class fuse is engineered to provide superior protection for rectifiers, heavy-duty UPS units, and large motor drives. It is specifically optimized to minimize let-through energy (I²t), preventing catastrophic damage to sensitive power semiconductors such as thyristors and IGCTs during short-circuit events.

The A070UD32LI900 is constructed with a high-durability ceramic body and silver-plated copper LI-style (Bolted Blade) terminal contacts, ensuring low contact resistance and excellent heat dissipation. The internal design utilizes pure silver elements surrounded by high-purity silica sand for effective arc quenching and a high breaking capacity of 200kA. This fuse includes an integrated Type K mechanical striker for visual status indication, which can also be utilized for remote signaling via an auxiliary microswitch.

Technical Specifications

• Manufacturer: Mersen
• Catalog Number: A070UD32LI900
• Item Number: H219785
• 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: LI (Bolted Blades)
• Indication System: Integrated Mechanical Striker (K-Type)
• Pre-arcing I²t: 275 kA²s
• Total Clearing I²t at Rated Voltage: 1,850 kA²s
• Power Dissipation at Rated Current: 135W
• Standards Compliance: IEC 60269-4, UL 248-13 Recognized, RoHS Compliant
• Quantity: Pack of 3