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='68473' and id < 4421047 and id<>'4421047' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='68473' and id > 4421047 and id<>'4421047' order by id asc limit 5