|
楼主 |
发表于 2008-7-18 10:52
|
显示全部楼层
PTC是属于半导体性质的,是会导电的,所以tracking试验不适用,所以只能按最差的3B了。
; {0 a* e R; o# Y9 U4 x' M6 r7 N如果按照污染等级2的确就没这个问题了,但是我们是按照P3考核. |4 @& F/ g. `2 Z* _8 i
pollution degree 2: only non-conductive pollution occurs, except that occasionally a
. T6 [6 |# u) ~4 etemporary conductivity caused by condensation is to be expected;4 u( d7 |0 I0 [4 g- S0 p
pollution degree 3: conductive pollution occurs or dry non-conductive pollution occurs that
, f% \* s4 K1 Qbecomes conductive due to condensation that is to be expected;+ ]$ m5 o: u& P9 t! \/ l5 k* H- Z
PTC是暴露在空气中的(灰尘颗粒算导电的还是不导电的?),我觉得还是算作P3比较合理。 |
|