采用二次谐波制动原理的变压器差动保护，当二次谐波含量超过定值时(   )。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69519' and id < 4503784 and id<>'4503784' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69519' and id > 4503784 and id<>'4503784' order by id asc limit 5