The RENFE Class 490, also known as the ETR 490, is an electric multiple unit constructed by Alsthom and Fiat Ferroviaria and operated by Spanish rail company Renfe Operadora on its Alaris long-distance services. Since the introduction of the Alaris service, only ETR 490 units have been used for this service. Therefore these trainsets are often known as Alaris themselves. The units were the first actively tilting units to go into regular service in Spain.
Unlike other members of the Pendolino rail family, the ETR 490 trainset is composed of only three cars: two motors vehicles, with driving cabs, and a trailer vehicle in the centre. Its motor system is similar to that of an electric multiple unit because its pantograph is not located on a locomotive. The motor cars on either end of the train contain a pair of motor bogies, with one asynchronous motors per bogie. Static and other converters are also located underneath the motor cars.
The central passenger car is divided into two spaces: half is passenger seating while the other part is a bar and restaurant. A section of this car is also dedicated to people with mobility and accessibility impairments. The dimensions of the ETR 490 are reduced compared to its Italian model. These dimensions favour aerodynamic stability and speed. The cars are also built out of lighter materials that allow the train to move faster and put less stress on the tracks. The power consumption of the Alaris trainset is considerably less than the Italian ETR 460, almost reduced by one third.
The tilting mechanism of the ETR 490 is quite similar to that of the second and third generation Pendolino series, controlled by gyroscopes, devices measuring oscillation, and speedometres. The tilt is limited to eight degrees when fully activated when compared to a horizontal surface. Disk brakes control pneumatic and rheostatic braking.