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
' e8 B: _* f3 u# `) i1.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
6 b. }! G7 l  Z! e1 j2.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？
/ q! r4 w: P$ R: N/ c3.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

8.7.2.1 A unit having components such as resistors, semiconductor devices, capacitors, and the like shall
6 F: V6 c% q0 S% W) |' f! znot exhibit a risk of fire or electric shock when a simulated short circuit or open circuit is imposed. In
; g" ~0 C0 u: t, l9 P5 w7 {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
include: short-circuits and open circuits of semiconductor devices and capacitors, faults causing open
& a7 u- N. }9 P0 b# N# U( s* q9 ucircuits of resistors and internal faults in integrated circuits.

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% ]5 o& ?+ g: s& zException No. 1: Circuits in which maximum power levels have been determined to not exceed 50 W need
+ Z  ?" p+ F( D9 o8 Z$ vnot 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
2 }+ r! a. Q( O( g7 ~, V" E" s5 yneed not be subject to this test.
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8.8 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,
& p9 H$ c/ ^: [' H( H: rincluding 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.