The 447 series, successor to the 446, improves on the latter with greater acceleration, a major increase in maximum speed to 120 km/h, lower energy consumption, a considerable drop in maintenance costs and greater travel comfort. The series is almost identical to its predecessor meaning it can be coupled as a multiple unit.
Access to the vehicles is facilitated by the moving footboard on the three side access doors to each of the vehicles that make up the composition. The doors give access to the platforms that are integrated into the passenger lounge. The passenger lounge is diaphanous, although the seats and furniture are grouped together in four subdivisions, around the corridor and the accesses. Units from number 72 to 117 have a different seating arrangement, in rows of 2 by 2. There are also 12 extrapontines per carriage, which increases the unit's number of seats by 36.
The lighting is fluorescent along a central channel, reinforced by halogen light points on the sides. The air conditioning system is integrated into the roof of the central platform, with backup heaters under the windows. The vacuum toilet, located in the trailer carriage, consists of a compact module with the drain pipes to the outside. The module incorporates a non-automatic door, busy sign, bowl, sink, soap dispenser, toilet roll holder, hand dryer, bin and mirror.
Inside display monitors inform passengers of the destination station, the itinerary, the connections of each station, the time and the outside temperature. Meanwhile, external destination display monitors are digitally controlled from the driving desk. In the compartments, stations are announced both visually and acoustically through the PA, which can broadcast recorded advertisements from the cab, via the ground train or by the driver.. The PA also broadcasts ambient music from a CD.
Finally, it should be noted that the unit has a ground train radiocommunication system, Asfa, and double effect "dead man". It also has an information centre to notify the driver of any incident or breakdown and how to act
The 447 series is the successor to the 446 and is conceived in three-phase current technology, which was first incorporated in Spain, with the following main improvements:
In addition, the bid specifications required that the new unit be compatible with the 446 series units so that they could circulate coupled with multiple interconnecting controls, and of course the speed, traction and brake performance of the resulting train correspond to the 446. Also, the differences in the vehicle's body, interior design, and driving and control desk were minimal compared to the 446 units.
The design and development of the technical and construction project of the 447 series was carried out between 1991 and 1992. In total, the 183 units that make up the series were awarded and built in four batches. In February 1993, after eight months of on-track testing, the first train in Valencia began its commercial service in Valencia, which is in turn the prototype of the 71 trains that made up the initial batch of 447 series trains, acquired in April 1991.
The second batch (072 to 117) consisted of 46 trains and has as a more significant difference with a more classic seat distribution, thus increasing the number of seats and decreasing the standing places. These units were delivered between 1995 and 1996. Between 1998 and 1999 the third batch, consisting of 20 units acquired in July 1997, was delivered, while the 46 units that make up the last batch were acquired in March 1998. The 183 trains are running on the Cercanías lines of Madrid, Barcelona, Valencia and Murcia/Alicante. Each train consists of three carriages, two engines at the ends and one trailer in the centre. Up to a total of 4 units can circulate in multiple coupling.
These trains, conceived and designed by Caf in their mechanical part and auxiliary equipment, and by Siemens in the electrical power and control equipment part, were built by ADtranz, now Bombardier, Caf, and Siemens.
The structure of the body is self-supporting and made from welded copper steel. The end carriages, located in the engine carriages, are made of polyester that case an anti-collision structure. A large anti-impact armoured window provides the driver with high visibility and protection.
On the outside the 446 and 447 units are identical, differentiated by grilles and by the numbering of the carriages; the letter "M" or "R" is displayed on the top part of the front and side in white on the 446 units and in yellow on the 447 units.
The interior layout is repeated in the three carriages, except for the driver's cab, where the control desk, the top devices panel and the cabinets with the low voltage apparatus, the air conditioning control and communication, information and safety equipment are located. There are just two cabinets in the trailer carriage, as well as an area with space for a toilet.
Each carriage is accessed via 3 platforms on either side, each installed with automatic, double, electric drive, nesting-sliding doors, equipped with moving footboard and with a 1,300 mm opening. These platforms provide four passenger compartments set up around a central aisle and equipped with fixed and folding seating. The wall and ceiling lining is made of non-stick polyester. The floor height is relatively low (1,150 millimetres) and uniform throughout the unit. The sides, slightly inclined to improve their aesthetics, have fixed reflective glass windows, which from the outside give the appearance of being a continuous band. The windows installed on the front and sides are armoured, for greater safety whilst moving. Finally, the practicable longitudinal skirts complement the line of the train.
Under the chassis, each engine carriage carries the main box, transformer and choke, static converter for auxiliaries, air conditioning condensing units and pneumatic panels. The high-voltage box, battery box, battery charger or air conditioning condensing units, compressors, pneumatic panels and spare parts box are located in the trailer carriage. The braking resistors are on the roof of each engine carriage and the two pantographs and lightning rods on the trailer. There is a Scharfenberg coupling system with mechanical, pneumatic and electric coupling; being automatic in free end carriages and semi-permanent in coupled end carriages.
Traction and auxiliary systems
The power and control equipment consists of two traction and electric brake circuits, identical but independently operating, each one installed in each engine carriage, except for the common parts that are located in the trailer carriage. The power collection equipment, common to both sets of power equipment, consists of two pantographs; a general circuit breaker; two lightning rods and two sets of disconnectors.
The power and control equipment incorporates the use of GTO thyristors, using fibre optics for sending signals and control with microprocessing techniques. This configuration of the traction equipment, with three-phase technology, sets the 447 series apart from the 446 series units, since both trains have identical general characteristics in terms of functionality and driving. This innovation allows for greater accelerations and a top speed of 120 km/h compared to the 100 km/h of the 446 series, despite both trains having the same continuous rating traction power (2,400 kW).
Meanwhile, the 447's energy consumption is 12 per cent lower than that of the 446 series trains. This reduction is achieved through higher engine performance, better recovery electric brake functionality (with recovery rates of up to 30 percent) and less weight. The 447 TU weighs 162 tonnes compared to 167 tonnes in the 446. Maintenance costs are also 25 per cent lower than those of the 446 TU.
Each engine carriage carries four engines (eight in total for the unit). These engine work on each of the engine carriage axles by means of a WN-type double gear elastic coupling.
Each set of power equipment basically consists of:
The train's auxiliary equipment includes:
There are two temperature control units per carriage that provide cooling and heating, backed-up by heaters located at the floor level of the compartments. They are controlled from the cabins. Temperature control features are 34,500 kcal/h in each carriage (22 kW) and 34.5 kW per carriage in heating.
Bogies and brake
Each carriage has two double-axle bogies, with superficially tempered solid wheels, grease boxes with bearings and elastic crank guidance.
The bogie's chassis is made of welded steel. The primary suspension uses coil springs, with the secondary suspension being pneumatic. Both have vertical shock absorbers, with the secondary suspension also having horizontal shock absorbers.
The carriage body rests on the bogie's chassis, with no bogie bolster, so horizontal loads are transmitted by pivot and drag rods.
The engine bogie has two asynchronous traction motors suspended from its structure. Each motor has a separate transmission assembly consisting of a hollow tree coupling and gimbal system, and a fully suspended two-stage gearbox.
The pneumatic brake system of the engine bogie consists of four brake discs mounted on the wheels and driven by four pneumatic cylinders and two brake blocks equipped with accumulator spring for the parking brake. The trailer bogie brake system consists of four brake discs positioned on the axles, driven by four brake cylinders, two of them with built-in parking brake.
All axles have tachogenerators The end axles have flange grease and railguards-snowplows.
The TU has the following brake systems:
The service brake is combined, electric and/or pneumatic and recovers energy to the extent that the catenary admits it. The braking action is controlled by a microprocessor. This unit has the possibility of driving at a preset speed.