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|  DSH 724
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| Measurement of Conductivity: T( v* j8 f" P1 q, ]9 ?. J
| 7.3" |% G# T2 c6 A$ T$ ]* h6 r
| 60112(ed.4)2 E& f: r/ C. x5 `' w! ]$ h" i$ N
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2 Q& U, K, H3 G$ P1 {4 UQuestion:
$ C! V9 O* P5 h8 qClause 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.
' Z9 l2 s. W9 y, \Are CBTL:: R( c6 W+ B3 [( C( [
- (a) expected to use this method of measurement for solution conductivity; or
- h5 a6 A1 c5 z" I- w( _- (b) can a suitable conductivity meter with a measurement frequency in the range 1 kHz to 2 kHz be used; or
$ s2 [5 E6 z& z" i2 q; r0 S- (c) can any suitable conductivity meter (different measurement range) be used.
, c O3 s% {/ C7 D7 y4 kDecision:% ^- ]; G) }3 y2 N
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.4 l+ B: D% v! m8 `* Q8 s1 A
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发表于 2012-9-5 10:19
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