Never underestimate the power of some idiot that can cross wires and get something to work until it burns. As a qualified electrician I would find the 2 pole breaker that controls the outlet in the panel. If the outlet was controlled by 2 separate single pole breakers or if I found other suspicious wiring I would check other outlets once the circuit was dead if they were affected. I hesitate to consul you since I can't know what you find, it could be straightforward or a dangerous nightmare. Tom Evans SV TAPPAN ZEE Manzanillo MX