In the ’90s at a Melbourne university, a computer was being set up after purchase, only to find it wasn’t working.
As the technician plugged the Ethernet cable into the rear of the computer, the Safety Switch (RCD) in the building tripped and disconnected power to the computer.
It was found that the factory moulded IEC power supply cord had reverse polarity between Active through to Earth, livening up the chassis of the computer and functional earthing of the network card. When the thernet cable was plugged in, the computer was then shorted to an alternative earth path. Had the installation not have been protected by an RCD, the technician could have received a serious electric shock.
While new-to-service equipment is not required to be inspected, tested and tagged in Australia, manufacturing faults can and do occur, resulting in incidents such as the one above, indicating that it would be prudent to test and tag new equipment on introduction to service.