DSH 168A Resistance to corrosion of current-carrying parts

小米

广东安规检测
有限公司提供：

小型摆管淋雨试验机

IPX5X6X7喷水试验机

1000L恒温恒湿箱

各种试验指现货

可程式恒温恒湿试验箱

水平垂直燃烧机

自动卷线器试验机

耐划痕试验机

各种灯头量规现货

灼热丝试验机现货

GB1002插头量规

IPX1-X7淋雨现货

IEC61347/UL935镇流器热试验箱

灯具防风罩

IK冲击试验机

UL498插头插座量规

VDE0620插头插座量规

稳定性试验台

家电温升测试角

针焰试验机现货

热电偶焊机现货

家电125mm试验指

E12灯头量规

无绳壶无绳电熨斗插拔寿命试验机

IEC60335试验指甲

DSH 168A

Resistance to corrosion of current-carrying parts

-

Generality

Question:
) X) |# n: s6 c7 u8 t" b* q) E  i" y7 ]How to judge whether a current-carrying part is resistant to corrosion ?
$ `/ s& x/ \) B+ }; CDecision:
CEE Recommendation n. 9 “Corrosion of current-carrying parts” may be applied to judge whether a current-carrying part is resistant to corrosion .
6 R" H8 W' R1 z, n! |  N$ iIt is quoted in CB Bulletin No. 41 (September 1981).
In the following, for convenience, is reported a part of it:
RECOMMENDED TEXT, SCREWS, CURRENT-CARRYING PARTS AND CONNECTIONS.
a) Current-carrying parts and parts of terminals shall be of a metal having, under the conditions occurring in the equipment, adequate mechanical strength and resistance to corrosion.
. o8 y5 s9 V  `6 }& cCompliance is checked by inspection and, if necessary, by measurement and by chemical analysis.
; d5 I. O- {# [3 u$ O0 Z) A7 GAfter all the tests of the relevant specification, the current-carrying parts and parts of terminals shall show no appreciable deformation.
; S% a4 I1 d' UExamples of suitable metals, when used within the permissible temperature range and under normal conditions of chemical pollution, are:
- copper,
- an alloy containing at least 58% copper for parts that are worked cold or at least 50% copper for other parts,
- stainless steel containing at least 13% chromium and not more than 0,09% carbon,
+ \: V. b8 I8 p- steel provided with an electroplated coating of zinc according to ISO Publication 2081-1973, the coating having a thickness of at least:
* 5 T ISO grade “1 mild” for ordinary equipment,
$ c, }& A) s. t. E& K1 P& w, E- S* 12 T ISO grade “2 moderate” for jet-proof and splash-proof equipment,
* 25 T ISO grade “3 severe” for jet-proof and watertight equipment.
- W7 i$ e6 u) ^! V4 g  \- steel provided with an electroplated coating of nickel plus chromium according to ISO Publication 1456-1974, the coating having a thickness at least equal to that specified for:
% [& H  u" }" V6 `( H1 _+ e0 _. _* service condition no. 2 for ordinary equipment,
" a* ?4 T; `2 P/ A- r( F0 v* e* service condition no. 3 for drip-proof and splash-proof equipment,
* service condition no. 4 for jet-proof and watertight equipment.
, @. L/ E. d% k8 N, y$ U2 d' {- Aluminium and its alloys, provided special measures are taken for removing, where necessary, the oxide layer, for obtaining a sufficient and durable contact pressure and for ensuring that the point of connection withstands the corrosion test specified;
, ]9 B$ i2 r: N$ ]however, until a suitable corrosion test and an electrical performance test are available, aluminium and its alloys should preferably not be used for current-carrying parts and terminals within the equipment.
Zinc and other metals which are soft or liable to creep are not considered to be suitable for current-carrying parts and terminals .
The thickness of the electroplated coatings on steel may be determined by the magnetic method described in ISO Publication 2178-1972, or by microscopical
measurement described in ISO Publication 1463-1973.
! |: m: X' l1 h/ C8 z. T8 Gb) Under moist conditions, metals showing a great difference of electrochemical potential with respect to each other shall not be used in contact with each other .
Compliance is checked by inspection.
0 _% E3 s. ~; I

4 K! q; `0 ?; v! U# o$ `& q! N7 E! q