According to Enel requirements

Our alarm announcers according to ENEL’s prescriptions are designed in line with the prescriptions DQ1987A2NCI – DQ2026A2NCI – DQ1931A2NCI and LV28 of ENEL, drawn up in 1990 to unify the technical and construction characteristics of the alarm announcers at the national level. Within our product range there are panels for auxiliary alarm signals, used in the “LV” control panel of the primary cabins and the LV28 Reed Relays used in the electrical control and control panels.