The problems to solve. The mains can bring about problems like the following: You power shutdown. General problems of absence of tension in the mains. Surge. Tips of tension that surpass the normal one and that they would be possible to be produced for example by storms. Voltage drops: They can produce dull unexpected produced for example by a high consumption when igniting equipment of great power like the motors. According to the problems to correct it is possible to be chosen between three types of SAIs: Offline: It is the economic type. The computer science equipment is fed on the electrical current until this fault (a power failure or sobrevoltage variation that can put in danger its integrity) moment in which it would happen to use the current stored in the battery of the SAI.
It is solely of economic but when acting as battery would discard personally them. Interactive (Inline): It is an intermediate model between offline and the online one with an accessible cost. Besides serving as battery usually uses a filter against fluctuations of tension. (Or they would have to be) they are used in small surroundings. Online: It offers an independent exit of the autogenerated normal network that it protects of any anomaly.
The computer science equipment would be fed directly on the SAI protecting it of any electrical problem. They are more expensive and they are used in industrial surroundings. The great majority of the SAIs uses software to control all functions and behavior against the problems of electrical provision so that a registry of events can be taken, management of alarms that warn of the happened thing and to even automate tasks to realise dull a correct one of the computer.