SITOR fuse link, with female thread on both sides, In: 250 A, aR, Un AC: 680 V, Un DC: 440 V, front indicator SITOR 3NE and 3NC semiconductor fuses protect power semiconductors from the effects of short circuits. As an important element of the SENTRON protective component line for electronic installations, the SITOR fuse system from Siemens provides effective protection for personnel, equipment and plants with reliable shutdown in the event of an overload or short circuit. The area of application also includes frequency converters with fuses in the input circuit and in the DC link and also UPS systems and soft-starters for motors. Key features of the Siemens SITOR fuses: 1. Extremely fast-acting switch-off characteristic compared to conventional LV HRC fuses. 2. Power semiconductors are also reliably protected in the event of a short-circuit. 3. The Siemens quality standard ensures very good characteristic curve accuracy. 4. SITOR cylindrical fuses are approved in accordance with IEC a