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|  DSH 572
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) c0 J: a! n' ^ | Abnormal operation3 e5 v; f6 @( Z# p8 ^
| 19.11
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Question:0 l) Y! l8 D; b7 r
If a conductor of a printed circuit board becomes open-circuited, the appliance is considered to have withstood the particular test, provided all three of the following conditions are met - The base material of the printed circuit board withstands the test of annex E,1 L- h# `, [3 ]; |1 B3 r1 n
- Any loosened conductor does not reduce clearances or creepage distances etc...) N) U7 E }4 z) n
- The appliance withstands the test of 19.11.2 with the open-circuited conductor bridged.' _6 O4 r2 f4 I. W! M5 Y/ ?% [
According to the third condition above, must it be considered that only one specially designed track cannot be enough protection? (Because the test has to be repeated with the track bridged).: D8 g9 _$ d+ c4 h5 ]: U
Decision:- O1 n' c. D8 s, k! H; {
The track is only considered as an intentionally weak part if there is a declaration of the manufacturer about that, otherwise it shall be considered as a conductor and 19.11 applies.
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发表于 2012-9-8 20:51
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