Twisted Copper
Monday, July 26th, 2010Can I use 12 gauge copper black wire with multiple strands of copper twisted together as a grounding wire?
Or does it have to be a solid copper wire? And I do it's not good to mix colors 
Don't take electrical advise from untrained and unqualified people. A 12 gauge grounding conductor must be bare or green. 2005 National Electric Code 250.119. It cannot be marked with green tape. Only wires 6 gauge and over can be indentified with tape. You can strip off all insulation on exposed sections to comply with the code. Stranded or solid is fine as a grounding conductor. #12 wire is ok for grounding on circuits of 20 amps or less only, except in special cases.