耿家云磊 发表于 2013-9-27 14:34

UL 1993中，电气间隙不足时，是否可通过裸板耐压来豁免。

UL 1993中，6.6 电气间隙一节。6.6.4 b 中说了如果2V+1000DC可以过的话，就可以不要求电气间隙。我也一直认为这条是豁免条款。但今天我们客户工程师说，这一条只是说，一旦裸板耐压不过，就必须要做短路实验。即使过了，间隙也是要按table 6.1要求的。
求解！

Nezof 发表于 2013-9-27 14:40

PCB上的距离不够可以通过裸板耐压来代替

带电件到可触及表面上的距离必须按照表的要求来了

裸板耐压不过的话，有50W测试来再验证

耿家云磊 发表于 2013-9-27 15:07

Nezof 发表于 2013-9-27 14:40 static/image/common/back.gif
PCB上的距离不够可以通过裸板耐压来代替

带电件到可触及表面上的距离必须按照表的要求来了


50W测试？

jsspace 发表于 2013-9-27 16:08

耿家云磊 发表于 2013-9-27 15:07 static/image/common/back.gif
50W测试？

请参考UL8750第8.6章节

Samjxh 发表于 2013-9-27 16:41

你们 对标准真熟！！

zt012359 发表于 2013-9-30 13:34

jsspace 发表于 2013-9-27 16:08 static/image/common/back.gif
请参考UL8750第8.6章节

哥！UL8750有8.6？为什么我的只有8.4啊   我的是台湾翻译的我的有问题吗还是没有更新的？

xiaodeng 发表于 2013-9-30 13:55

zt012359 发表于 2013-9-30 13:34 static/image/common/back.gif
哥！UL8750有8.6？为什么我的只有8.4啊   我的是台湾翻译的我的有问题吗还是没有更新的？

估计标准错误无疑，
8.6 50-Watt point power measurement test
8.6.1 To determine the point beyond which any circuit is unable to deliver more than 50 W of available
power, a wattmeter and an adjustable external load resistor are to be arranged as illustrated in Figure 8.1. Power limitation is permitted to be accomplished either by the inherent design of the circuit (per 8.6.2), by the opening of a circuit component (per 8.6.3), or by the opening of a protective device (per 8.6.4).
8.6.2 The external adjustable load resistor is to be initially set for its maximum resistance. The adjustable
resistance is then to be reduced gradually to the point of maximum delivery wattage as indicated by a
peak reading on the wattmeter.
8.6.3 For a circuit without a designated current limiting device, a circuit component that opens in less than 1 minute at any power delivery level less than 50 W and that precludes delivery of 50 W for more than one minute is considered to effectively limit the circuit output to less than 50 W, if the test can be repeated two additional times on new samples with comparable results.
8.6.4 For a circuit with a designated current limiting device, a closed shorting switch is to be connected
across the current limiting device and the adjustable resistance is then to be reduced to result in a power dissipation of exactly 50 W as indicated by the meter. The switch across the current limiting device is then to be opened and the time required for the device to open is to be recorded. A current limiting device that opens the circuit in less than 1 minute is considered to effectively limit the circuit output to less than 50 W.

zt012359 发表于 2013-9-30 14:00

xiaodeng 发表于 2013-9-30 13:55 static/image/common/back.gif
估计标准错误无疑，
8.6 50-Watt point power measurement test
8.6.1 To determine the point beyond ...

:'(   求英文原版！拼了

xiaodeng 发表于 2013-9-30 14:02

zt012359 发表于 2013-9-30 14:00 static/image/common/back.gif
求英文原版！拼了

其实论坛上已经有了。 搜索一下就出来了。
http://bbs.angui.org/thread-112715-1-1.html

zt012359 发表于 2013-9-30 14:16

xiaodeng 发表于 2013-9-30 14:02 static/image/common/back.gif
其实论坛上已经有了。 搜索一下就出来了。
http://bbs.angui.org/thread-112715-1-1.html

THANK YOU ！一直看的是2008版本！ :L
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