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
1 Q8 M7 X' n* e9 @5 V1.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？
8 h! Y7 }3 |- M; D" m; X" f3.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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: z( a. `' z( a" G# s# d8.7.2 Component failure test

8.7.2.1 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
. }0 b5 m" i2 n6 e: u5 h: @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
6 z. Q. B- v- `2 K5 finclude: short-circuits and open circuits of semiconductor devices and capacitors, faults causing open
' A8 t- x* g9 M$ scircuits of resistors and internal faults in integrated circuits.
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  b! {# ]! d! b- h+ Y! SException 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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, B, k. e$ x0 p! U$ Z9 w4 M8 M8.8 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,
+ o! G' T( p$ y# k3 pincluding short circuit, measured after one minute of operation exceeds a defined limit. For the purposes
) h  C* J. ~6 Q9 w) M% y* r' sof 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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