变压器的电源电压一般不得超过额定电压的（   ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69465' and id < 4499065 and id<>'4499065' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69465' and id > 4499065 and id<>'4499065' order by id asc limit 5