Measurement of Conductivity! Y$ q) @0 w5 ^' b- v: q: K( h
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Question: ; a: s o" j0 ^( \2 u. J/ cClause 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.$ x' n2 j% p1 Q( f6 x; t
Are CBTL: 6 v; F. E6 x8 J6 e- (a) expected to use this method of measurement for solution conductivity; or& R$ H3 u" K" _
- (b) can a suitable conductivity meter with a measurement frequency in the range 1 kHz to 2 kHz be used; or ! x. d% m6 Z( Z0 l1 p9 Z- (c) can any suitable conductivity meter (different measurement range) be used. . m q% N( [" C1 [ Q& tDecision: / Y7 H- _0 F; @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. / z( L: [ Q! m * }0 q7 Q+ O. y2 s- Y$ o[attach]75559[/attach]5 b1 d8 G$ \' k5 ?8 a% \: X
DSH 724) N$ \1 ^( L* p' ~" p. d