It is the acronym of Alternate Current.

Is the spanish acronym of Acumulador de Carga Rápida. Rapid charge accumulator.

Automatic Dropping Device 

Air Generation and Treatment Unit

Acceptable Index of Precursors

Include the expenses for support staff (structure) and expenses not directly payable between projects are recorded. 

European National Security Authorities

Auxiliary Power Supply 

Automatic Run Registration

It is the acronym in Spanish of Anuncio de Señales y Freno Automático. Signal announcement and automatic brake.

It is the acronym of Automatic Train Operation.

It is the acronym of Automatic Train Protection.

Cannot be entered manually, rather a specific BAAN module must be used to record them. This module is different in every case and an automatic entry is generated when the task finishes.