The Siemens SD-400 and SD-460 are

light rail Light rail (or light rail transit, abbreviated to LRT) is a form of passenger urban rail transit that uses rolling stock derived from tram technology National Conference of the Transportation Research Board while also having some features from ...

vehicles (LRV) that were manufactured by

Siemens Mobility Siemens Mobility GmbH is a division of Siemens. With its global headquarters in Munich, Siemens Mobility has four core business units: Mobility Management, dedicated to rail technology and intelligent traffic systems, Railway Electrification, ...

between 1985 and 2005 for the North and South American markets. The SD-400 was built under Siemens' joint venture with

Duewag Düwag or Duewag (stylised in all caps), formerly Waggonfabrik Uerdingen, was a German manufacturer of rail vehicles. It was sold in 1999 to Siemens with the brand later retired. History Duewag was founded in March 1898 as Waggonfabrik U ...

and assembled at both Duewag's factory in

Düsseldorf Düsseldorf is the capital city of North Rhine-Westphalia, the most populous state of Germany. It is the second-largest city in the state after Cologne and the List of cities in Germany with more than 100,000 inhabitants, seventh-largest city ...

West Germany West Germany was the common English name for the Federal Republic of Germany (FRG) from its formation on 23 May 1949 until German reunification, its reunification with East Germany on 3 October 1990. It is sometimes known as the Bonn Republi ...

(

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

after

reunification A political union is a type of political entity which is composed of, or created from, smaller politics or the process which achieves this. These smaller polities are usually called federated states and federal territories in a federal govern ...

in 1990) and the Siemens factory in Florin, California. Siemens purchased Duewag in 1999 and the SD-460 was assembled entirely at the Siemens factory in California. The primary difference between the models is that the older SD-400 uses

direct current Direct current (DC) is one-directional electric current, flow of electric charge. An electrochemical cell is a prime example of DC power. Direct current may flow through a conductor (material), conductor such as a wire, but can also flow throug ...

motors An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power gene ...

, while the newer SD-460 uses alternating current motors. Both models were built with a "high-floor" design and equipped with 3-4 doors on each side for level boarding at high-platform stations and one door with steps for boarding at street-level. The SD-400 and SD-460 were manufactured and marketed alongside the older

Siemens–Duewag U2 The Siemens–Duewag U2 is a type of light rail vehicle (LRV), built by consortium of Siemens, Duewag and Wegmann & Co built between 1968 and 1990. The design was based on the prototype U1 tram built in 1965 for the Frankfurt U-Bahn. The U2 was a ...

LRV and later the

Siemens SD-100 and SD-160 The Siemens SD-100 and SD-160 are two related types of high-floor light rail vehicles (LRV), manufactured by Siemens Mobility for the North American market. A total of 431 vehicles were built by Siemens in Florin, California from 1992 to 2013. ...

vehicles. The U2, SD-100, and SD-160 all offered either level boarding at high-platform stations or steps for passenger loading at street level. This model has been replaced by the

Siemens S700 and S70 The Siemens S70 and its successor, the Siemens S700, are a series of articulated low-floor light-rail vehicles (LRV) and modern streetcars manufactured for the United States market by Siemens Mobility, a division of German conglomerate Sieme ...

, low-floor vehicles for passenger loading at street level and the

Siemens S200 The Siemens S200 is a high-floor light rail, light rail vehicle (LRV) manufactured by Siemens Mobility in Florin, California, beginning service in 2016. The S200 succeeds earlier Siemens high-floor LRV models, including the Siemens SD-100 and S ...

, a high-floor LRV for level boarding at high-platform stations.

Technical details

Both models have a common design, with frames built upon a B-2-B

truck A truck or lorry is a motor vehicle designed to transport freight, carry specialized payloads, or perform other utilitarian work. Trucks vary greatly in size, power, and configuration, but the vast majority feature body-on-frame construct ...

configuration mounted underneath a double-ended

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 ...

body, which has a seating capacity for 72 people and room for an additional 106 standing passengers. There are four high-level, inward-opening double bifold doors on each side of the vehicle for

level boarding Various terms are used for passenger railway lines and equipment; the usage of these terms differs substantially between areas: Rapid transit A rapid transit system is an electric railway characterized by high speed (~) and rapid acceleratio ...

, along with an additional low-level, single right-side doorway and steps at each end of the vehicle for low-level boarding. The dual-height door design was necessary on the Pittsburgh Light Rail system, which has both high-platform stations and traditional street-level streetcar stops. The Pittsburgh cars also have only three sets of doors per side as opposed to four on the others, omitting the left-side doors immediately ahead of the articulation joint in the direction of travel. The other operators of the SD-400 and SD-460 do not use the street-level doors in regular service. Both the SD-400 and SD-460 are powered by four individual Siemens

electric Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

traction motor A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric vehicle, electric or hydrogen vehicles, or electric multiple unit trains. Traction (engineering), Traction motors are used in electrically powe ...

s with each one developing 200

horsepower Horsepower (hp) is a unit of measurement of power, or the rate at which work is done, usually in reference to the output of engines or motors. There are many different standards and types of horsepower. Two common definitions used today are t ...

(149 kW) and creating a combined total power output of 800 horsepower (597 kW). The older SD-400 uses

(DC) motors, while the newer SD-460 uses

alternating current Alternating current (AC) is an electric current that periodically reverses direction and changes its magnitude continuously with time, in contrast to direct current (DC), which flows only in one direction. Alternating current is the form in w ...

(AC) motors. The SD-460 also uses updated electronic equipment with

insulated-gate bipolar transistor 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 ...

s (IGBT) compared to the SD-400. On both types, electric current is received via an overhead catenary wire, which supplies 750

volts The volt (symbol: V) is the unit of electric potential, electric potential difference (voltage), and electromotive force in the International System of Units (SI). Definition One volt is defined as the electric potential between two point ...

into the motors. More than 80 SD-400 units were produced between 1985 and 1993, with all being manufactured at Siemens' primary manufacturing plant at its home base in Germany, while nearly 70 SD-460 units have been produced since 1999, with all being manufactured at Siemens' secondary manufacturing plant at their American base in California as opposed to Germany. The SD-400 is used by

Pittsburgh Regional Transit Pittsburgh Regional Transit (PRT) is the public agency responsible for most public transportation services in the Greater Pittsburgh region in Pennsylvania. It is the second-largest public transit agency in Pennsylvania and the 20th-largest in ...

for the Pittsburgh Light Rail in Pennsylvania, while the SD-460 is used for the Valencia Metro in Venezuela. Both types are also used on the MetroLink system operated by Metro Transit in

St. Louis St. Louis ( , sometimes referred to as St. Louis City, Saint Louis or STL) is an independent city in the U.S. state of Missouri. It lies near the confluence of the Mississippi and the Missouri rivers. In 2020, the city proper had a populatio ...

. In 2023, Metro's board approved a $390.4 million contract with Siemens for as many 55 S200 battery-hybrid light rail vehicles to replace the oldest SD-400/460 cars.

Operators

References

External links

North American Light Rail Information
{{Siemens trams and light rail vehicles Port Authority of Allegheny County MetroLink (St. Louis) Streetcars of the United States Siemens tram vehicles 750 V DC multiple units Articulated passenger trains Train-related introductions in 1985 Train-related introductions in 1999 Light rail vehicles Electric multiple units of the United States Siemens multiple units Rolling stock of Venezuela

Technical details

Operators

See also

References

External links