大修、事故检修或换油后，220kV变压器在施加电压前静止时间不应少于(    )。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69522' and id < 4504111 and id<>'4504111' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69522' and id > 4504111 and id<>'4504111' order by id asc limit 5