|
|
|  DSH 7247 |' z' S0 J7 y( z- W+ d6 Q
9 P2 i' A R; Y# J# ]
| Measurement of Conductivity
1 e$ `2 {9 X# D$ q; f5 X0 t$ f) Y) n | 7.3) Z3 K+ ]( s/ f! }9 j
| 60112(ed.4)3 m1 ^3 z* i3 v; j0 U+ `
|
, p: D7 y1 x9 S ?+ q
Question:
+ J( X d2 a+ Q7 x3 ?. }7 DClause 7.3 requires that the conductivity of the tracking test solution “be measured with alternating voltage at a frequency in the range 1 kHz to 2 kHz. The procedure is described in IEC 60589”. The procedure in IEC 60589 utilises conical flasks with reflux condensors, platinised platinum electrodes, a conductivity cell and a resistance bridge. This appears to be a chemical standard rather than an appropriate electrical test laboratory measurement technique.
1 D$ I( }* X5 b3 x# bAre CBTL:5 ~8 G& }) M' e, M y
- (a) expected to use this method of measurement for solution conductivity; or
. b7 p+ K: E; Y5 B. q _2 U- (b) can a suitable conductivity meter with a measurement frequency in the range 1 kHz to 2 kHz be used; or, o- H0 t0 N, x# k, L7 |
- (c) can any suitable conductivity meter (different measurement range) be used.0 D3 n6 Y# r4 }" F5 b
Decision:" b& f1 O& Q; N3 n: Q) |) X
The Group decided that the “use of any appropriate conductivity meter with sufficient accuracy and uncertainty including the probe” is the only practical one - item (c) above.
$ z0 Y- n8 u b A* C1 ~6 j% A6 h! }
& ]0 S( X% z5 n" ?" { |
本帖子中包含更多资源
您需要 登录 才可以下载或查看，没有帐号？注册安规
x
|
/2 
|关于安规|小黑屋|安规QQ群|Archiver|手机版|安规网
( 粤ICP13023453-10 ) 
窥视卡
雷达卡
发表于 2012-9-5 10:19
收藏
分享
好帖
鸡蛋
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
抢沙发
千斤顶
显身卡