安规网

 找回密码
 注册安规
安规论坛 | 仪器设备 | 求职招聘 | 国家标准 公告 | 教程 | 家电 | 灯具 | 环保 | ITAV 签到 充值 在线 打卡 设备 好友| 帖子| 空间| 日志| 相册
IP淋雨机 | 证书查询 | 规范下载 | 资质查询 招聘 | 考试 | 线缆 | 玩具 | 标准 | 综 合 红包 邮箱 打卡 工资 禁言 分享| 记录| 道具| 勋章| 任务
水平垂直燃烧机 | 针焰 | 灼热丝 | 漏电起痕
IP防水防尘设备|拉力机|恒温恒湿|标准试验指
灯头量规|插头量规|静风烤箱|电池设备|球压
万年历 | 距元旦节还有
自2007年5月10日,安规网已运行
IP淋雨设备| 恒温恒湿箱| 拉力机| 医疗检测设备沙特Saber 埃及COI 中东GCC|CoC直接发证机构水平垂直燃烧机|灼热丝|针焰试验机|漏电起痕试验机
灯头量规|试验指|插头插座量规|灯具检测设备耐划痕试验机|可程式恒温恒湿试验箱 | 耦合器设备广东安规-原厂生产-满足标准-审核无忧
查看: 866|回复: 0

[其他] OSM_EE 13.4

[复制链接]
发表于 2017-1-8 17:26 | 显示全部楼层 |阅读模式
广东安规检测
有限公司提供:
Question:
9 q4 p1 q3 Z& Y9 x2 ^3 Y$ X9 G! `In EN 60950-1, there are requirements for fuses in Sub-clause 2.7.3:
4 ^5 |$ W' d7 X! ?1 |% N2.7.3 Short-circuit backup protection" K& B% ~" I+ s/ G6 k
Unless appropriate short-circuit backup protection is provided, protective devices shall have  p  b. E3 m. f: ?( n3 o& [4 D, k
adequate breaking (rupturing) capacity to interrupt the maximum fault current (including shortcircuit
) V9 j9 m  z/ acurrent) which can flow." b! d6 t2 R( F( _7 ]" t
For PERMANENTLY CONNECTED EQUIPMENT or PLUGGABLE EQUIPMENT TYPE B, it is permitted for
9 n+ _9 B% w3 ~) D/ ], Fshort-circuit backup protection to be in the building installation., M% L0 f2 U6 o- l  y9 D
For PLUGGABLE EQUIPMENT TYPE A, the building installation is considered as providing shortcircuit2 X  K" F, M# P2 B5 d9 x
backup protection.- N" m" S2 A3 r% s, W! K
NOTE If fuses complying with IEC 60127 are used in PRIMARY CIRCUITS, they should have high breaking capacity
8 L) L3 y6 x2 Z' u* W0 h(1 500 A) if the prospective short-circuit current exceeds 35 A or ten times the current rating of the fuse, whichever
5 c' g3 g: U+ R9 n/ \- o  R! nis greater.
( Z% l0 {4 q$ ]* H4 UThe 3 questions are concerning a Class II wall plug adaptor (a.c. mains input, d.c voltage output) that is Pluggable Equipment Type A. The fuse in the AC primary circuit, if equipped, is mostly not of the High Breaking Capacity type.
' a1 D, Y9 r. mQ1:
* w/ M* k2 q# Q5 V5 v% K  s  DSub-clause 2.7.3, first paragraph does not require that protective devices (ex. fuses) in AC primary circuits of a product must have an adequate breaking capacity if appropriate short-circuit back-up protection is provided. In practice, this means that fuses or circuit-breakers in the building installation are considered to provide this protection. In normal household installations, such protection allows currents up to 16A or 20A before they break a fault current. This means that no fault protection is provided up to a power level of 230V x 16A = 3680W, roughly 4kW.
( e" _* `. o, x. [Is a building installation that only breaks a fault current if it exceeds 16A, producing a faulty power consumption of roughly 4kW, considered as an <appropriate> protection?9 {7 s8 f" L) ?0 z/ q3 U" o/ U
Q2:/ X3 G5 F# l8 Z6 d1 ~/ {4 B% S$ A( S
Most fuses in the AC primary circuits comply with IEC60127 but are not of the High Breaking capacity type.
7 X4 P( e- B( ]# g, X. IHence, if a fuse is equipped in the AC primary circuit of the Pluggable equipment Type A product and this fuse complies with IEC60127, is compliance needed with the requirement of High Breaking capacity in the NOTE?; ~( E  C: }- y! C7 t3 G+ R
In this context, an explanation may be needed about the meaning of “prospective short-circuit current”: is this a steady state current or a higher short term current that can be well above the nominal 16A nominal fuse or circuit breaker value?4 [$ J& U) R5 P/ @
Q3:" _9 n6 r/ z9 i4 S$ x" ]: |# e  K
Sub-clause 2.7.3, first paragraph, requires an “adequate breaking (rupturing) capacity”. If Q2 does indeed not require a High Breaking capacity type, what are the parameters to determine that “adequate capacity”?
7 @. K5 R' d. s1 N2 e* v, }7 aDecision:
% z) V* A; l* q' _/ c) O" C3 AOSM agreed to the following:
8 r) K& t" y, b0 r$ j; ~A1: See 2.7.1 in common modifications5 C8 R+ b4 `; h/ G9 m! O2 f! M- X
A2: It is not necessary to have a high breaking capacity or enhanced breaking capacity fuse, as long as the fuse does not explode while performing the fault conditions.
9 t8 y9 n1 W9 n% L4 H) HA3: The test should be done on a 16A unloaded branch circuit (for UK see SNC) and the fuse in the product shall operate.* N: A! `$ F; Q# n3 o
EN 60898-1 circuit breakers type B are considered the most spread type in Norway and in several other countries.$ q( t% k! b' @; I
The OSM is of the opinion that type B can be used and it is assumed that this type of circuit breaker will cover the conditions in European countries.- _  h! ~/ o% Z1 s6 [: ~4 K
/ M+ [5 P6 |/ I8 o9 M( v1 f8 D

' Y8 X9 V; x  R4 U$ q3 H  t2 n6 Z& E- ~( ~

+ R/ [# R- ~1 x' G" N4 W' T1 x; ?' |. Y5 x: V

本帖子中包含更多资源

您需要 登录 才可以下载或查看,没有账号?注册安规

x
您需要登录后才可以回帖 登录 | 注册安规

本版积分规则

关闭

安规网为您推荐上一条 /1 下一条

QQ|关于安规|小黑屋|安规QQ群|Archiver|手机版|安规网 ( 粤ICP13023453-10 )

GMT+8, 2024-12-24 07:07 , Processed in 0.078737 second(s), 24 queries .

Powered by Discuz! X3.4

© 2001-2023 Discuz! Team.

快速回复 返回顶部 返回列表