【单选题】【消耗次数：1】
关于油断路器，下列说法中正确的是（）。??
①
只有少油断路器的油仅作为灭弧介质来用??
②
无论是多油断路器，还是少油断路器它们的油都只作为灭弧介质来用?
③
无论是多油断路器，还是少油断路器它们的油不但作为灭弧介质来用，还作为绝缘介质来使用。
④
只有多油断路器的油仅作为灭弧介质来用?
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【判断题】
在少油式断路器中，油只用来灭弧而不作绝缘用载流部分的绝缘是利用空气和陶瓷等绝缘材料。在多油式断路器中，油不仅作为灭弧介质，同时兼作带电部分之间和带电部分对地之间的绝缘，所以用油量较多。
①
正确
②
错误
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