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
* d* G8 m% C6 g* L* v4 Z1.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
8 g6 X/ R0 }$ i- _" b# z9 `' i2 @- U- ~2.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？
" A8 h; r3 _0 V( ]/ Y0 ?/ u3.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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8.7.2 Component failure test
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5 g* ^$ }3 b4 H/ q8 G1 a; U8.7.2.1 A unit having components such as resistors, semiconductor devices, capacitors, and the like shall
3 v: ]4 {4 D, C. b* W6 Rnot exhibit a risk of fire or electric shock when a simulated short circuit or open circuit is imposed. In
preparation 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
- |" h! n% M2 S# m+ E  _  R4 binclude: short-circuits and open circuits of semiconductor devices and capacitors, faults causing open
circuits of resistors and internal faults in integrated circuits.


$ E1 q0 p( k8 i: V$ X! WException No. 1: Circuits in which maximum power levels have been determined to not exceed 50 W need
not be evaluated for component failure.
5 T; s1 v- q  [7 Z$ V4 v6 v. k
% G! s$ k" h3 m0 IException No. 2: Devices supplied by a source operating within the limits for risk of fire and electric shock
0 T% Q9 j5 l3 X2 F/ Sneed not be subject to this test.




, M* _% ?! M$ F8 d8.8 Circuit power limit measurement test
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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
) V6 T( ^  `- z8 D! a# J- iof 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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