Hooking up a stove range, all wires are black how do tell which is positive and negative and ground?
Based on experience: IF all three supply wires are black, then one of them should have another colored stripe, a "tracer" color, on it which would indicate the ground/neutral wire. This would be an older set-up with no dedicated ground. IF there is no wiring with any colored tracer on it, then I would say the wires need to be traced back to the panel, confirmed as to which each wire really is, and properly labeled. In today's world a dedicated ground should be put in at this time. David