Techie touched one box and the lights went out

"The very instant the plug seated, the building went completely dark. Proctors soon emerged from the two exam halls that were in use and demanded Kent explain what he had just done, because he had clearly ruined Very Important Exams. Because the kit Kent was working on connected to a UPS, he was able to determine they were all working perfectly. The building's network was fine, too. But every other electrical appliance or light in the building was dead."

"Kent stepped outside to call his dispatcher and was comforted to see the entire street was dark. It was not my UPS. It was a beautifully timed, utterly ordinary grid failure. But because Kent had been doing something to do with electricity, he was prime suspect."

Kent was contracted to modernize a live testing center by installing new desktops, servers, switches, and UPS systems in two unused halls while maintaining operations in two active exam halls. After successfully upgrading the first hall, he began work on the second. The moment he plugged the new UPS into mains power, the entire building lost electricity. Exam proctors immediately blamed Kent for the outage. However, Kent's new UPS equipment functioned perfectly, the network remained operational, and he discovered the entire street was dark. The blackout was caused by a grid failure, not his installation. Despite this evidence, Kent remained the primary suspect due to his involvement with electrical work at the precise moment of failure.

Read at Theregister