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1.有个功率放大器的信号输出端的输出电压是危险电压而且试验指可触及,但是已经标记了危险带电符号,请问该输出端是否需要再加防护?如果需要,为什么,不需要又为什么? f0 O' F7 {. w5 p
?( [8 f8 s% p; ?) {" gGB8898-2001中9.1允许信号输出端子带电,但要求标有5.2b的闪电符号。+ e2 i, v; F/ m4 s
为什么需要加防护罩?见CTL决议285,在决议里要求加防护罩。( B) d, Q- _3 J9 T2 u2 M. X' x
见:http://www.iecee.org/ctl/sheet/pdf/sheet285.PDF
4 d; n- Z$ X; u- J. A( |试验室为何要执行CTL决议,见IECEE网站的相关说明,这里就不翻译了。- W7 D- x6 V* w" Z
WHAT IS THE CTL ?1 Y, X# c, v/ L; {
The Committee of Testing Laboratories is the technical branch of the IECEE and the biggest forum of technical experts representing 295 CB Testing Laboratories, located in 52 different Countries, and operating under the responsibility of the relevant National Certification Bodies (NCBs) members of the IECEE.
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2 {1 R5 m; R* u) b2 f# zSTRUCTURE OF THE CTL
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The Chairman and the Secretary of the CTL are appointed by the Certification Management Committee of the IECEE (CMC) on nomination by the CTL.# P$ T& f% w& z/ i& x, _3 }3 A( ]
$ o) y6 u2 K6 a$ K+ cThe term of office of the Chairman of the CTL is three years. He is immediately eligible twice for re-appointment in the same office, each time for a further period of three years.
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The CTL reports to the IECEE-CMC.
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, L' m" s& f7 c, |5 z0 |3 l% T2。国标GB8898中的9.1.1中说到“信号输出端子的接触件,由于功能原因,这些接触件必须危险带电,则这些接触件按第8章对可触及导电零部件的规定的要求与电源隔离即可”请问这怎么理解?7 S; k9 S5 ^1 @2 I
+ M& L/ _; j, g/ Y& O; m d一般功放由隔离变压器与电源隔离。
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个人认为,GB8898有缺陷,新版的60065标准已经把它修改了
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