A.變頻調(diào)速 B.轉(zhuǎn)子串電阻 C.串極調(diào)速 D.改變電動機繞組極對數(shù)
A.210M; B.220M; C.230M; D.240M
A.標(biāo)準(zhǔn)值; B.認定值; C.允許值; D.優(yōu)選值