These fuse holders are supporters for fuses with size up to 14X51mm. They are capable of working under heat caused by rated current and expected short impacting current up to 100KA. It can also function as a fuse disconnecting switch by multi-phase combination. There are two in/out lines at the RT18N fuse base, providing a power cut function. The RT18L type has a safety lock to lock the fuse carrier when disconnected to avoid wrong operation; it can also be equipped with an indicator, which goes on when the fuse linke breaks.Rated insulate voltage up to 690V; Working frequency 50Hz AC; Conventional free air thermal current up to 125A; Compliant with GB13539.1, GB13539.2, GB13539.6, GB14048.3 and IEC269-1, IEC269-2, IEC269-2-1, IEC947-3 .