FS Class E632

FS class E632
An E632 heading a passenger train near Santhià (2006)
Power type Electric
Build date 1982-1987
UIC classification B-B-B
Wheel diameter 1.040 m
Wheelbase 12,650 m between bogies
2.150 m between axles in each bogie
Length 17.800 m
Width 3.000 m
Height 4.310 m
Locomotive weight 103 tons
Electric system 3,000 V DC
Traction motors DC series
Transmission 36/64 gear ratio
Top speed 160 km/h
Power output 4,200 kW
Locomotive brakes Oerlikon FV4E
Safety systems RSC4; SCMT
Career FS Trenitalia
Number in class 65[1]
Nicknames "Tigre", "Tigrone" (E652), "Tigrotto" (E620 FNM)
First run 1982
Disposition In service
FS class E633
An E633 with a cargo train in Santhià, 2006.
Power type Electric
Build date 1979-1987
UIC classification B-B-B
Wheel diameter 1.040 m
Wheelbase 12,650 m between bogies
2.150 m between axles in each bogie
Length 17.800 m
Width 3.000 m
Height 4.310 m
Locomotive weight 103 tons
Electric system 3,000 V DC
Traction motors DC series
Transmission 29/64 gear ratio
Top speed 130 km/h
Power output 4,200 kW
Career FS Trenitalia
Number in class 147[2]
First run 1979
Disposition In service

The FS E632 and E633 are two classes of Italian railways electric locomotives. They were introduced in the course of the 1980s.

The locomotives are nicknamed Tigre ("tiger").

Contents

History

The E632/E633 were the first Italian locomotives to be provided with electronic traction control system, on the basis of the experiments made with the E444.005 test locomotive. They were designed to fulfill a requirement from the Ferrovie dello Stato (or FS, then the quasi-monopolist of Italian railways) for a new locomotive to be used with medium-weight passenger trains and a similar one for cargo services on steep lines.

The first unit ran on October 11, 1979. After a troublesome program of tests with the first five prototypes, a first order for 90 engines (75 E633, the cargo version, and 15 E632) was issued. Regular services began in 1983 in northern Italy. Once the teething problems were solved, the class proved highly successful and reliable.

Technical details

Differently from many of the previous FS classes, the E632/633 carbody is not articulated. The power plant is made of three 1,635 kW FS T850 DC motors, mounted on single-engined bogies, each with two axles. Each motor is provided with a three-frequency chopper which takes place of the resistor network used on older Italian locomotives (rheostat). This allow the motors to run for an indefinite period of time without risks.
The two classes have different transmission gear: 36/64 for the E632, with a maximum speed of 160 km/h, and 29/64, with a maximum speed of only 130 km/h but a higher tractive effort. Since the beginning, all units were provided with the standard 78-wire cable for coupling with driving passenger cars, useful in the formation of commuter push-pull trains. 40 E633s were also fitted with a 13-wire ZDS cable (comando multiplo) in order to allow hauling with multiple units by only one engine crew, from the "master" locomotive.

The locomotives have, in addition to pneumatic brakes, a rheostatic braking system. The braking rheostat is placed on the roof, between the pantographs. Curiously, the air brake employs a mixed shoes-disc system (one shoe per wheel and one disc per axle), due to space issues about the motor placement; also, E632 have 10" brake cylinders, while E633 8". The chopper regulation and the rheostatic braking allow the driver to set an automatic speed control; the locomotive will try to keep the set speed by electrically braking or by tractioning if needed. This group has been the first in Italy that allowed this.

Related development

The E632/633 was used as base for the development of the E491/E492 locomotives for use with 25 kV ac lines in Sardinia, which however were never mass built.

Class E652 is a type of locomotive derived from E633/2. They unite the acceleration and hauling capacities of E633 with the speed of E632 (160 km/h); externally they are almost identical to E632/3, but the electrical part is very different. The first unit was built in 1989, and have been the first Italian locomotive with electronic board diagnostics and relative screen on the driver's desk. At this time, they are all assigned to the Global Logistic (Cargo) division of Trenitalia, hauling freight trains, though sometimes can be seen hauling passenger trains (often long-range ones) on rescue services due to failures.

The B-B locomotive E620 of Ferrovie Nord Milano (nicknamed Tigrotto) is a two-bogie version of the class.

Footnotes

  1. ^ Plus one prototype
  2. ^ Plus 4 prototypes