A bit of excitement at work today. There was a small electrical fire over the weekend. Fortunately someone was working on Saturday, noticed one of the servers wasn’t responding, went into the server room and saw the plug on a heavy-duty extension cord glowing slightly, with smoke coming out. He unplugged it from the wall, made sure it went out, then rearranged some power cords so he could get back to work.
We’ve bypassed the UPS involved until we can be absolutely sure that (a) it didn’t cause the short and (b) it wasn’t damaged. There’s charring on the outside of the plug where it was in contact with the extension cord, though nothing like what we found inside the other plug. The hot wire had burned clean through, leaving charcoal dust all over the inside of the plug. The cable and the circuit breaker are both rated for 20 amps, so the most likely explanation (since the UPS wasn’t belching flames) is that the cable was faulty – and an extension cord is a lot easier to replace than a 130-lb power supply!