Shocking (!) demo of the danger of arc flash

[Mark Hennessy]

Each exchange had a battery room. The batteries were made up of lots of large concrete cells, cast in-situ, lead acid type. Each was about the size of an under-counter fridge, from memory. The idea was to keep the exchange runing for up to an hour, in case the standby generator had starting problems! No smoking in the battery room or bang!

Interesting - I've only seen the types with conventional batteries. I thought that concrete was sensitive to acid attack - was it a special mix or lined with something?

Cheers,

Mark