只要电源星形连接时，均有线电压有效值为相电压有效值的倍。（   ）

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69472' and id < 4500100 and id<>'4500100' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69472' and id > 4500100 and id<>'4500100' order by id asc limit 5