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The fuse-link is short-circuited during the test and the current passing through both the fuselink+ Q! q; g) N7 o; l
and the short-circuit link under the relevant fault condition, is measured:
, i. O( w; z/ l2 k– if this current remains less than 2,1 times the rated current of the fuse-link, the- z* m2 [7 S8 W- h# @+ x
temperatures are measured after a steady state has been attained;
" v9 `5 G" b: X2 S& V- A4 m( ?– if this current is either immediately 2,1 times the rated current of the fuse-link or more, or
- D. j! n6 a+ R p& B' c+ yreaches this value after a period of time equal to the maximum pre-arcing time for the
0 W( }( [* x8 |relevant current through the fuse-link under consideration, both the fuse-link and the shortcircuit
' g) b8 ~) o3 S7 V4 K3 a" Plink are removed after an additional time corresponding to the maximum pre-arcing: h6 P6 d- O% W- B
time of the fuse-link under consideration and the temperatures are measured immediately.
; a% R) |. I% l5 r- n" Q% J# b: w5 _: o* A3 z; {
以上是有关熔断体的操作问题,我想问的是:* N# k- l/ o: S) \1 j8 M8 {
1.为什么是2.1倍的额定电流值,不是1.5倍,2倍,也就是为什么是2.1不是其他值
. j7 x5 _& f" p9 H7 d3 ?) [$ u$ q w! ]$ C2.pre-arcing time 怎样计算呢? |
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