ALe 426/502 TAF
An FNM TAF in Milan Cadorna station |
| Power type |
Electric |
| Builder |
Ansaldobreda, ABB, Firema |
| Build date |
1996-2000 |
| Total production |
100 |
| AAR wheel arr. |
Bo2+22+22+2Bo (EMU4) |
| Gauge |
1435 mm |
| Length |
103.970 mm |
| Width |
2.820 mm |
| Height |
4.300 mm |
| Locomotive weight |
273 t |
| Electric system(s) |
3000 V DC |
| Current collection method |
Pantograph |
| Transmission |
20/101 |
| Top speed |
140 km/h |
| Power output |
3640 kW |
| Tractive effort |
214 kn |
| Locomotive brakes |
Oerlikon FV4E |
| Career |
Trenitalia, FNM |
| First run |
1997 |
| Disposition |
In service |
ALe 426/506 TAF (acronym of Treno ad Alta Frequentazione) is an Italian Electric Multiple Unit (EMU) used mainly on commuter regional trains.
Two different companies employ them: Trenitalia and Ferrovie Nord Milano (FNM).
Concept design has been made by Italian designer Pininfarina.
Recently some slightly modified version of the EMU have been purchased by Moroccan Railways,
Description
Each train is formed by fixed sections of four bi-level pieces: two motorized units (ALe 426/506) and two coaches between them (Le 736). Two sections can be coupled togheter, but by now it is not possible on Trenitalia units (on FNM ones is common practice).
The total capacity of the train is of 469 seated and 372 standing passengers.
Technique
ALe 426/506 employs asynchronous three-phase traction motors feed by the 3000 V DC catenary, which produce a characteristic sound while accelerating and dynamically braking.
Motors are mounted on one bogie per motorized unit, for a total of two motorized bogies per section.
This choice, however, has not proven too wise: first of all the power is very high in respect of the weight (3640 kW for 273 tons.), and the poor distribution of traction power along the train (only on the edges) induces poor performances in case of poor adhesion.
In fact TAFs are known for their frequent wheel slippage.
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