Is it possible for a black wire to be hot, but to cause reverse polarity in a GFCI when it's connected to the brass screw?
A no-contact voltage tester shows that the black wire is hot. The white wire and ground wires do not trigger the voltage tester at all.
Yet, when I connect the black wire to the brass screw on a new GFCI receptacle, and the white wire to the silver screw, and the ground wire to green, the polarity is reversed. The no-contact tester shows that the large slot on the receptacle is hot, while the small slot does not trigger the tester.
I've tested with multiple GFCIs, so it's not a case of a bad receptacle.
Likewise, putting a different, LED contact tester across the white wire and ground wire will cause the tester to light up. Putting it across the black wire and ground wire does nothing.
How is this possible?