SITOR - Cylinder fuse insert, 22x58 mm, 40 A, aR, Un AC: 690 V, Un DC: 700 V, DC according to UL semiconductor protection fuses SITOR 3NE, 3NC protect power semiconductors from the effects of a short circuit. The SITOR fuse system from Siemens is an essential component of the SENTRON protection devices for electrical installations and provides effective protection for people, equipment, and systems through safe disconnection in overload and short circuit situations. The application area additionally includes frequency converters with fuses in the input and DC intermediate circuit, as well as UPS systems and soft starters for motors. Siemens SITOR fuses are distinguished primarily by: 1. Super-fast disconnection characteristics compared to conventional NH fuses. 2. Power semiconductors are also safely protected in the event of a short circuit. 3. The Siemens quality standard ensures very good characteristic curve fidelity. 4. SITOR cylinder fuses are approved according to IEC and UL and mostly also CCC, making them suitable for worldwide use. 5. Partially suitable for installation in NH fuse bases, in NH fuse load disconnectors, and load disconnectors with fuses. Siemens offers a comprehensive portfolio of protection, switching, measuring, and monitoring devices, installation distributors, as well as switches and sockets for safe and efficient electrical infrastructure in buildings and industry.