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
5 I: G5 X/ @. w; {1.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
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？
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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+ _6 @) V% G; r; V7 Y7 v8.7.2 Component failure test
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' ?3 S  p0 q% M8.7.2.1 A unit having components such as resistors, semiconductor devices, capacitors, and the like shall
not exhibit a risk of fire or electric shock when a simulated short circuit or open circuit is imposed. In
9 S5 m* G+ {2 S/ y! R: A7 mpreparation for component failure tests, the equipment, circuit diagrams, and component specifications
( A2 h. y& ^3 E& R; r& Jare examined to determine those fault conditions that might reasonably be expected to occur. Examples
2 i( m6 f' M. w" i- Dinclude: short-circuits and open circuits of semiconductor devices and capacitors, faults causing open
! q( M# ?- q' Q) lcircuits of resistors and internal faults in integrated circuits.


# |$ @6 j3 i$ a, O. ?  E% X: G1 o: VException No. 1: Circuits in which maximum power levels have been determined to not exceed 50 W need
not be evaluated for component failure.

Exception No. 2: Devices supplied by a source operating within the limits for risk of fire and electric shock
need not be subject to this test.
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" x. [/ Y7 i* p1 B8.8 Circuit power limit measurement test
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9 _( V$ ~" V* N, @8.8.1 This test shall be used to determine if the power available to a circuit under any loading condition,
) d# W: M7 h2 |# R# z+ iincluding 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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