Inspected a remote distribution panel ( sub- panel) today. This was in a condo, I did not look at the main panel. I counted five wires coming from the main to this panel. The fifth wire is not connected to anything. Could someone tell me what this wire if for and what’s it doing here? I always thought only four wires to sub panel.
When I was an electrician, if I were running wires through a conduit or trace that would be impossible to run at a later time, I would run an extra just in case.
Of course, it may be as simple as a helper running one too many wires by mistake.
Hey david you mentioned it was a condo. Could be the building has 3 phase, and the extra wire was run by the builder not knowing if the units would need it or not. It used to be fairly common to see 3 phase for HVAC in some residential settings.