分接开关一般设置在高压侧，原因有（   ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69442' and id < 4497119 and id<>'4497119' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69442' and id > 4497119 and id<>'4497119' order by id asc limit 5