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以下UL PAG中的对保险管炸开的现象的判定指导:
2 r: w5 D7 B3 m5.3.8-1 Bursting fuses( z8 f' C5 o* \0 R. @
STANDARD IEC/UL 60950-1
! J6 |1 `8 A& s/ @1 LAPPLICABILITY UL(C-UL) and IEC/ I+ c: v2 U# ?7 ?1 @+ z Y) S
(Sub)CLAUSE/ANNEX NUMBER: 5.3.8* |" J. j/ M$ U; e0 J' |8 Q& I
(Sub)CLAUSE/ANNEX HEADING: Compliance Criteria for Abnormal Operating and Fault Conditions
+ X+ h( N+ {# }$ [8 g& wOTHER RELEVANT (Sub)CLAUSES/ANNEXES
+ U% K1 W) _) n Z( [& l2 d# g9 Y(as Applicable): @! I% j0 b% p! k9 \
2.7.3, 5.3.6, 5.3.8.1, 5.3.8.2! f4 K0 l. L7 z' V5 ^& O
DESCRIPTION OF ISSUE:
4 }% i+ m, W2 z7 y* Q: jType of Issue: Technical; P* I) p' S, W* _( s& [, J
During fault testing in the Primary circuits of switch mode power supplies (SMPS) and other ITE,/ H$ ]4 a( |' j' p( n
sometimes a fuse that provides supplementary (non-branch circuit) overcurrent protection and
& C d7 \6 ` mthat complies with either IEC 60127 or UL 248-14 will burst while clearing the circuit/ r' \: K3 C( N; |# q5 B& t1 l
Is this an acceptable result and termination of the test?( \: j. K- Q! T- _% E" n& O" j% u
APPLICATION GUIDELINE:
- L; C/ C# p- z0 F% J1 _( o% YA fuse that bursts is not an acceptable result and termination of a test. If a fuse bursts during
7 J7 w+ Y, L6 p- ]4 }! G# O/ Dfault testing per sub-clause 5.3, it does not have adequate breaking (rupturing) capacity.# f$ O$ t6 D. H0 l
Therefore, such a fuse should be replaced by the manufacturer with another fuse having high! k: Q% \/ e5 ?& E5 U0 D4 w. x2 g
breaking capacity. This consideration applies to fuses complying with both IEC 60127 and UL' R5 }6 {4 r. n: P( y m
248-14.6 E. |! k6 y7 [; n% }9 k( q0 i
Placement of heat shrink or similar tubing over the fuse assembly is not a suitable solution to
! h; X+ f! i* j! x2 H; Uwholly mitigate potential hazards associated with a bursting fuse. |
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