原理图必须有足够的尺寸，使图例、符号、装置、代码等都能被视力正常的人看清。应尽量避免使原理 图翻页。
A.Schematics must be readable to a normal visioned person, so legends, symbols devices, codes, etc., should be of sufficient size. The schematic diagram should be designed to turn over the page when the content is necessary. B.The schematic diagram must be of sufficient size that legends, symbols, devices, codes etc., are readable by persons with normal vision. Turn-page schematic diagram shall be avoided to the extent practical. C.The schematics symbols, devices, codes etc. must be legible, so people with normal vision should avoid turning the schematic pages as much as possible正确答案B
