Hello,
Electrical wire and cable specifications disallow the use of copper with conductivity less than that for annealed Electrolytic Tough Pitch Copper (ETP). See specifications CDA 110 ETP Copper, ASTM B 187, and ASTM B 152 copper. If hard copper is utilized as in the case in a very few circumstances, the electrical conductivity is 97% of the annealed Electrolytic Tough Pitch Copper (ETP) conductivity but regardless it is still ETP copper.
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com
519 641- 3212