This product is suitable for indoor AC 50Hz, rated voltage 7.2 kv-40.5 kv power systems, as a transformer and other power equipment overload or short-circuit protection components. And can be used with other protective electrical appliances (load switches, vacuum contactors) . This type of fuse can reliably break any fault current between 2.5-5 times the fuses' rated current and 50KA of the rated break current under specified operating conditions