Full Description IEC 60644:2019 applies primarily to fuse-links used with motors started direct-on-line on alternating current systems of 50 Hz and 60 Hz. Standardizes time-current characteristics to formulate additional pulse withstand requirements regarding testing and to give guidance for the selection of fuse-links to be used with motors. Note: Fuse-links according to this specification should comply with the requirements of IEC 60282-1.