标题: IEC61800-5-1 protective bonding test 疑问 [打印本页] 作者: piratedu 时间: 2013-10-15 13:58 标题: IEC61800-5-1 protective bonding test 疑问 本帖最后由 piratedu 于 2013-10-15 13:59 编辑 4 d* ]4 {4 B. f/ ?8 n7 V/ H1 K9 w
我有个问题想请教下各位大神，在看IEC61800-5-1时，标准中对protective bonding的测试给出了两种方法： 7 f) E# R2 b' R 9 f* G5 u! F, K& a. d1 U; Y/ S方法一在bongding横截面积满足要求的前提下通过测关注点到接地间的电阻来判断； 5 j t0 n0 ~' f4 f# ]0 I7 a( t- z) z. k& B& [0 Z
方法二是通过测量bonding两端的电压来判断，但标准中未给出under fault conditions下的具体fault conditions的定义及测试方法。, E# _) R" D% o. h: F+ d8 z* t2 n
* u2 a3 ], S; }- {5 D$ e想请教各位，你们在遇到该问题时是如何考虑的，谢谢。5 Q9 o' n% m/ a6 [. ^
# p" t7 D& [! z8 L9 Q; r1 ~附 标准内容： E0 o+ B4 P4 n+ O( x! B5 s8 Q* `4.3.5.3.2 Rating of protective bonding $ R+ f0 M1 y* ?7 f' k% HProtective bonding shall withstand the highest thermal and dynamic stresses that can occur to the PDS/CDM/BDM item(s) concerned when they are subjected to a fault connecting to accessible conductive parts. ' d- {0 e { G ?& q# TThe protective bonding shall remain effective for as long as a fault to the accessible conductive parts persists or until an upstream protective device removes power from the part. % `' ^$ N7 d) P* [8 oNOTE In cases where the protective bonding is routed through conductors of low cross-section (for example, PWB5 S3 ]9 G- C; N5 H& K
tracks), particular care should be taken to ensure that no undetected damage to the bonding circuit can occur in the1 _6 x c C+ g4 ]& L/ H6 {8 w
event of a fault. : x' L& }' q9 v$ F T) T' FThese conditions will be satisfied if the cross-section of the protective bonding conductor is the same as that for the protective earthing conductor according to 4.3.5.4. For testing, see 5.2.3.9.: e/ L7 N v0 }8 S1 i" P Alternatively, protective bonding may be designed to meet the impedance requirements of 4.3.5.3.3. ; U" z6 x D6 \2 v5 t0 ?4.3.5.3.3 Protective bonding impedance & h: Y) |1 ~2 z' nThe impedance of the protective bonding shall be sufficiently low that: - R5 q! J3 p7 @• during normal operation, no voltage exceeding continuously 5 V a.c. or 12 V d.c. can persist between the accessible conductive parts and the means of connection for the protective earthing conductor,8 `9 f7 X. t# Y/ Q) @# C5 O' p
and. _4 W2 o" K! z p
• under fault conditions, no voltage exceeding AC-2 or DC-2 in Figure 7 can persist between accessible conductive parts and the means of connection for the protective earthing conductor until an upstream protective device removes power from the part. The upstream protective device considered for this requirement shall have the characteristics required by the installation manual according to 6.3.7. . N' ]* X5 ~$ D- E4 ~, H- u% t/ r8 D, Q 作者: feiniaoo 时间: 2014-8-20 23:12
建议采用方法一，特别是大型的产品，以免进行故障实验造成损坏。 ) Z* w: ^2 z% t* Z: ?% T( @6 J对已小型的变频器可以考虑方法二，我觉得方法二就是要用最严格失效来评估，也就是会在可触及外壳上能产生最高电压的失效。。。。。作者: ok_hmh 时间: 2014-8-21 17:29
普遍采用方法一，方法二还没有做过。作者: yeanling 时间: 2014-10-26 10:45
采用方法一吧，方法二确实不太好操作。