UL 8750 故障测试中的8.7.2 中Exception No1对于不超过50W的电路可以豁免故障测试

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UL 8750 故障测试中的8.7.2 中Exception No1对于不超过50W的电路可以豁免故障测试。三个问题
+ ~* r: Q1 y; h5 w. t1.是不是说只要经过8.8 Circuit power limit measurement test的评估确定这个电路是小于50W的就可以豁免故障测试
- e6 I% n5 c; X; O$ \( y2.这个50W的电路不论输出是高压还是低压都可以豁免吗？还是说低压输入的电路？
3.目前有一个带电池的灯具，电池输出为12V，灯具只有10W，里面有电路，这个电路需要做故障测试吗？

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+ u3 {2 m" X1 @8 ]4 M  L8.7.2 Component failure test

8.7.2.1 A unit having components such as resistors, semiconductor devices, capacitors, and the like shall
5 r1 x1 o3 }) z; b( Onot exhibit a risk of fire or electric shock when a simulated short circuit or open circuit is imposed. In
, ]' Z% m- r4 ]0 E# Gpreparation for component failure tests, the equipment, circuit diagrams, and component specifications
are examined to determine those fault conditions that might reasonably be expected to occur. Examples
+ C. E8 M( F% V/ r/ w$ N) \* S+ tinclude: short-circuits and open circuits of semiconductor devices and capacitors, faults causing open
- n! y/ b( I; ?. Tcircuits of resistors and internal faults in integrated circuits.

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Exception No. 1: Circuits in which maximum power levels have been determined to not exceed 50 W need
" z1 o$ t+ E! V( L. M; {not be evaluated for component failure.

/ X2 i- X6 v  d, KException No. 2: Devices supplied by a source operating within the limits for risk of fire and electric shock
6 o1 v$ q: W7 A+ ?/ j* l& Z! g7 ineed not be subject to this test.
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. A, J: E& g$ D& h, W8.8 Circuit power limit measurement test

8.8.1 This test shall be used to determine if the power available to a circuit under any loading condition,
including short circuit, measured after one minute of operation exceeds a defined limit. For the purposes
of this test, the limit (for example, 15W or 50W) is referred to as PLIMIT. This test is applied to a circuit
(under evaluation) to determine if it has a power draw of PLIMIT or less.

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