The circuit on which the ballast is tested is to be protected by Class H non-renewable fuses at ten times the input current rating of the ballast or the next higher ampere fuse rating but in no case less than 20 amperes.是什么意思_The circuit on which the ballast is tested is to be protected by Class H non-renewable fuses at ten times the input current rating of the ballast or the next higher ampere fuse rating but in no case less than 20 amperes.在线翻译_英语_读音_用法_例句