The text below is the transcript from the Long Power Outage Detailed video. An audio-described version of the video is also available.

VO: Sometimes we may have to remove the power supply for an extended period of time. This could take up to eight hours for some complex but vital pieces of work. If we are inspecting and maintaining the internal working of high voltage equipment. This can only be done under the most stringent safety conditions and never with the equipment live. On overhead light networks, If we are replacing old or poor condition equipment, we will need to remove power supplies to allow this to be done safely. We will also remove power supplies if we need to move vehicles or equipment close to power lines. Sometimes, we can connect the generator to keep customers on supply while we work elsewhere. Changing over cannot be done live, and so we may remove the supplies for a short time, to protect our staff and the equipment, while we connect or remove the generator. We plan our work to keep these power outages to a minimum and try to ensure that we complete the work within the allocated time.