交流接触器的电寿命约为机械寿命的（）倍。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='27224' and id < 2260100 and id<>'2260100' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='27224' and id > 2260100 and id<>'2260100' order by id asc limit 5