The NT3 fuse is one type of low-voltage fuse in the NT series, used in electrical installations for overload and short-circuit protection. This series of fuses conforms to national standard GB13539 and International Electrotechnical Commission standards IEC 60269 and EN60269. The products are manufactured by companies such as Zhejiang Zhengrong Electric Co., Ltd. and Shanghai Longrong Electric Co., Ltd., and are used in chemical, mining, electronics, and electrical industries.
The NT3 fuse is suitable for AC 50Hz circuits with a rated voltage up to 1140V and a rated current up to 1250A. In addition to overload and short-circuit protection (gG/gL), it can also be derived for short-circuit protection of semiconductor equipment (aR) and short-circuit protection of motors (aM). The rated breaking capacity of this series of fuses is up to 120kA. Its structure consists of a variable cross-section fusible element made of pure silver or pure copper/silver sheets, encapsulated within a high-strength ceramic fusible tube. The fusible tube is filled with chemically treated high-purity quartz sand as the arc-extinguishing medium. The fusible element may be equipped with an indicator or an impactor. In addition, the NT3 also exists as a fast-break fuse type, primarily used for short-circuit protection of semiconductor rectifier components or rectifier devices, with a rated breaking capacity of 100kA or 200kA.
