This test can be done by the following methods.
In this method; the sample is immersed in persulphate solution and comparing the solution after the test with an equal volume of reference standard color reagent for depth of colors.
In this method, the mass of copper dissolved is expressed as grams of copper per square meter of wire immersed in the persulphate solution.
Persulphate solution must be freshly prepared.
Test sample for method A should of such length that there would be the sufficient extra length at two ends of the specimen.
These extra lengths of the specimen would be projected from the solution surface in which it is immersed during Persulphate Test.
Normally as per standard, the length of the test sample taken is given by L=300/d + 80 mm, where d is the nominal diameter of the conductor in mm.
For method B length of the sample is chosen as per practicing standard for example one such table from Indian Standard is given as reference.
Similar to method A test sample of method B should also be of such length that there would be sufficient extra length at two ends of the specimen in addition to the length specified in the standard.
These extra lengths of the specimen would be projected from the solution surface in which it is immersed during Persulphate Test.