The BBC news website tells us (https://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-55979665) that:

“A large swathe of Edinburgh and the Scottish Borders was plunged into darkness following a power outage on Sunday night.

“SP Energy Networks said about 88,000 homes experienced the power cut just after 21:00.

“Households in the capital were affected, as well as properties as far south as West Linton and Cardrona.

“The power cut, due to a fault on the transmission network, lasted for up to 45 minutes.”

That power cut affected the Informatics Forum, among other places. If you’re wondering why our main computing services were not affected, well, we have our fairly-recently-installed server room UPS to thank for that.

At the start of the power cut, the UPS switched over to its battery supply and reported an expected run-time of 57 minutes. The power cut in the Forum lasted about 40 minutes. At the end of that time, the UPS reported that its batteries had been run down to about 27% of their capacity – i.e. the ‘expected’ and ‘actual’ figures for the performance of the UPS more-or-less match.

It’s always nice when something works out, isn’t it?

Note that our UPS is sized so that, were it supporting its full potential load of 200 kW, it should have a battery run-time (or ‘autonomy’, to use the official UPS jargon) of 30 minutes. Our current total server room power load is about 110 kW.

In the UK, lengthy power cuts are thankfully relatively unusual events; generally, 95% of all mains outages last for less than five minutes

Power cut, Sunday February 7th 2021 / Computing Systems by is licensed under a