所谓的母线充电保护是指（   ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69381' and id < 4491725 and id<>'4491725' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69381' and id > 4491725 and id<>'4491725' order by id asc limit 5