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.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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7 z( j2 @7 r1 W$ k) l6 V$ k/ T8.7.2 Component failure test
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8.7.2.1 A unit having components such as resistors, semiconductor devices, capacitors, and the like shall
7 q( {, Y$ z0 L) U, g8 q( c7 xnot 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
0 ]. y! [; e& c  k2 a. d+ [are examined to determine those fault conditions that might reasonably be expected to occur. Examples
include: short-circuits and open circuits of semiconductor devices and capacitors, faults causing open
circuits of resistors and internal faults in integrated circuits.


Exception No. 1: Circuits in which maximum power levels have been determined to not exceed 50 W need
not be evaluated for component failure.
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Exception No. 2: Devices supplied by a source operating within the limits for risk of fire and electric shock
* B* M0 q$ X7 d  b$ G0 uneed not be subject to this test.

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8.8 Circuit power limit measurement test

2 }, d! H. R' w7 g$ H8.8.1 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
: l+ ~9 W$ K  S1 ]  J(under evaluation) to determine if it has a power draw of PLIMIT or less.
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