The Type DT4 is a four-car
electric multiple unit
An electric multiple unit or EMU is a multiple-unit train consisting of self-propelled carriages using electricity as the motive power. An EMU requires no separate locomotive, as electric traction motors are incorporated within one or a number o ...
(EMU) train type operated by the
Hamburger Hochbahn AG
Hamburger Hochbahn AG (HHA), founded in 1911, operates the underground system and large parts of the bus system in Hamburg, Germany. Its name comes from the initial name given to the Hamburg metro system, ''Hochbahn'' (German: ''elevated railway' ...
on the
Hamburg U-Bahn
The Hamburg U-Bahn is a rapid transit system serving the cities of Hamburg, Norderstedt, and Ahrensburg in Germany. Although referred to by the term U-Bahn (the "U" commonly being understood as standing for "underground"), most of the system ...
system since 1988.
Formation
Every DT4 train consists of four cars, which are formed as two
articulated
An articulated vehicle is a vehicle which has a permanent or semi-permanent coupling in its construction. This coupling works as a large pivot joint, allowing it to bend and turn more sharply. There are many kinds, from heavy equipment to buse ...
half-sets with two cars each. The cars don't have
gangways, but feature windows in the inner car ends.
Interior
The interior consists of transverse seating bays.
Widescreen
Widescreen images are displayed within a set of aspect ratio (image), aspect ratios (relationship of image width to height) used in film, television and computer screens. In film, a widescreen film is any film image with a width-to-height aspect ...
passenger information displays are to be fitted to the whole DT4 fleet, with works scheduled to be completed in 2022.
Technical specifications
The trains have steel car bodies and a
three-phase
Three-phase electric power (abbreviated 3ϕ) is a common type of alternating current (AC) used in electricity generation, Electric power transmission, transmission, and Electric power distribution, distribution. It is a type of polyphase system ...
propulsion system.
Thyristor
A thyristor (, from a combination of Greek language ''θύρα'', meaning "door" or "valve", and ''transistor'' ) is a solid-state semiconductor device which can be thought of as being a highly robust and switchable diode, allowing the passage ...
inverters are used in the DT4.1 and DT4.2 trains, and the DT4.3 through DT4.5 trains use
GTO-pulse inverters.
The DT4.56 and DT4.6 trains use
IGBT
An insulated-gate bipolar transistor (IGBT) is a three-terminal power semiconductor device primarily forming an electronic switch. It was developed to combine high efficiency with fast switching. It consists of four alternating layers (NPNP) that ...
-pulse inverters.
Each four-car set has four powered bogies and two non-motored
jacobs bogie
Jacobs bogies (named after Wilhelm Jakobs, 1858–1942, a German Mechanical engineering, mechanical Railway engineering, railway engineer) are a type of Rail transport, rail vehicle bogie commonly found on Articulated car, articulated railcars an ...
s. The powered bogies are equipped with
water cooled
Cooling tower and water discharge of a nuclear power plant
Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and non ...
three-phase
asynchronous motor
An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor that produces torque is obtained by electromagnetic induction from the magnetic field of the stator winding. An induction motor theref ...
s.
History
The development of the DT4 began in 1986, and the first unit was completed on May 30, 1988. Passenger service began on October 17 of the same year.
The DT4 trains are being refurbished since 2011. They receive a newer interior appearance, similar to the interior of the
DT5 trains. One car of set 140 was refurbished for testing purposes in summer 2010. Regular refurbishment started in 2011.
References
External links
Hochbahn fleet information
{{Hamburg U bahn stock
Hamburg U-Bahn
Electric multiple units of Germany
750 V DC multiple units
ABB multiple units