I wanted to inquire if there was a code requirement to have two separate Automatic Transfer Switches i.e. one for life safety systems such as elevator load, fire pump etc. and another for utility loads. Is it general design principle to have two separate ATS for life safety and general utility loads?
First, there's no code, but depending on some points we do our choices, that are :
1 – The total power's value of the life loads, and the power's value of the general loads that should be also supplied from the generator, certainly after integrating the ” ku – utilisation factor ” and ” ks – simultaneity or diversity factor “.
2 – The place of the life loads and the place of the general loads.
3 – If all these loads ” Life & General ” are supplying from the same panel or not.
4 – Depending of the supplying ways of these loads.