I'm experiencing some electrical issues with the apartment I'm subletting. While connecting up a projector/speaker setup using outlets from different sides of the room, we discovered (through means of frying our electronics) that the grounds on each side of the room are at different potentials.
When measured with a multimeter from the ground pin of one outlet to the ground of the outlet across the room, we get 120VAC. Keeping the same reference ground pin across the room, neutral also measures at 120VAC and power measures at 0VAC.
It seems like one of the outlets must have it's wiring backwards, but a visual inspection of the wires (at least the outlet side) checks out and an outlet tester claims they are all correct.
Will that outlet tester detect if neutral and ground are powered and power is grounded? Is that condition particularly dangerous?
Note: I'm not proposing that I do any of the electrical work myself, I'm just curious about what went wrong and where.