Põhielektrienergiaallika seiskumise korral peab toimuma automaatne ümberlülitus avariielektrikilbile. Peakilp ja avariielektrikilp peavad olema paigaldatud vee ja tule suhtes võimalikult ohutule kohale.
If the emergency electrical power source is an accumulator battery and the main electrical power source fails, the accumulator battery must be automatically connected to the emergency electrical switchboard and supply power for an uninterrupted period of three hours to the systems referred to in the first, second and third indents of the second subparagraph.
