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引用第9楼zange007于2011-12-06 11:17发表的 :
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N3 @: H; {$ E% R, ]) P" G非常感谢您。我有疑问的是:测试输出端子断地测试,是从输入端把断开(线路中的E开关);
* j/ j! q$ q& T6 b; K还是从次级把输出负与地线断开呢(就是把地线接次级点断开)。有什么判定依据吗?从标准里哪能找得到呢?% o( r7 b9 U% d" z+ z$ U3 G
因为以上两种断地测试的结果是不一样的,假如初级有与地的桥接Y电容的话。 For equipment having a protective earthing connection or a FUNCTIONAL EARTHING connection,
0 C! E/ u! T" H! K# x% K3 Q1 Eterminal A of the measuring instrument is connected via measurement switch "s" to the main
( N4 {0 Y2 E9 H, B, ?' y; Yprotective earthing terminal of the EUT, with the earthing conductor switch "e" open.
# z: p+ q( F2 A+ @The test is also conducted, on all equipment, with terminal A of the measuring network7 R- `% ~! e; u& J4 Q2 [
connected via measurement switch "s" to each unearthed or non-conductive accessible part, G5 [4 @: J7 F, z& c5 I$ r! u
and each unearthed accessible circuit, in turn, with the earthing conductor switch "e" closed
3 o3 G+ @9 Q! ]3 e这是标准上面说的,意思就是有地断地,没地接地~~
- M& \6 t2 r, Y) q& e如果你输入地断开来测得话,那得按3.5来卡(这和测接地金属外壳是一样的结果),但是标准里面讲我们测得地方是switch "s" to the main6 C0 y I: C( c
protective earthing terminal of the EUT,输出端子负端接地如果不能过接地连续性测试的话,他只能算是功能地,按没有接地的方式来测,输入的地接上,输出的地如果不断开测得值是个定值上面我有说过,所以输出端子负端地断开,那就按0.25来卡,一般是按这种方法来测得。 |
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