PKP class EW58

Pafawag 3WE and 3WEa (car type 301B+401B+301B, series EW58) are standard gauge three-car high-platform electric multiple units produced by Pafawag in Wrocław between 1974 and 1980, with a total of 28 units built.

Initially, these vehicles were intended for the Gdańsk and Warsaw railway hubs, but they were ultimately only operated in the Tricity. In the 1990s, most of the units were involved in accidents and subsequently scrapped. In 2010, there were plans to modernize the remaining 7 units in operation, but two years later, this refurbishment was canceled, and their service was terminated. By the end of 2016, it was decided to scrap 6 units and preserve the seventh as an exhibit.

The experience gained from the production and operation of 3WE units was used to build two units of the 6WE series in 1990.

In the mid-1960s, the electric multiple units (EMUs) in operation in Poland, which had been designed based on pre-World War II concepts, were becoming increasingly outdated compared to foreign vehicles. As a result, in 1964, the Railway Scientific and Technical Centre began developing the specifications for new units. Initially, two simultaneous projects were undertaken: low-platform units type 2WE and high-platform units type 3WE, which were intended for the Warsaw and Gdańsk railway hubs. However, due to the ongoing serial production of the low-platform EN57 units, the 2WE project was postponed, and it was decided to prioritize the development of the 3WE units.

The design for the 3WE units was completed in 1967 by Zbigniew Tyszka from the Railway Scientific and Technical Centre. In 1973, the Central Design Bureau for Railway Rolling Stock [pl] developed the construction documentation for these vehicles. The electrical components were initially led by Stefan Wróblewski, followed by Alojzy Kiełkiewicz, who collaborated with Eugeniusz Małecki, Zbigniew Durzyński, and Aleksander Płatkiewicz. Romuald Łużny, along with engineers Perk and Ludek, was responsible for the mechanical parts. The unit was designed for the operational conditions of the Warsaw railway hub, which involved a high frequency of trains on the Warsaw Cross-City Line, short distances between stops, and the need to achieve high speeds on suburban routes. To meet these requirements, the power and gear ratio (77:20) of the unit were adjusted, and a new motor with dynamic braking capability was designed. The dynamic brake was controlled by a thyristor-based motor excitation regulation system.

The first prototype was completed at the Pafawag plant in Wrocław in June 1974 and was showcased at the Poznań International Fair. In 1975, two additional units were delivered. These prototypes were tested at the Railway Scientific and Technical Centre under the supervision of Bogdan Paszkowski and were then assigned to the Tricity's Szybka Kolej Miejska to replace outdated rolling stock after the traction voltage was increased from 800 to 3,000 V DC.

In 1977, a pre-production series of five units was built, which, unlike the first three prototypes, featured an upper headlight. After receiving feedback from the trial operations, design modifications were made. Starting in 1978, the units were produced in a modified version known as 3WEa, which featured a compartmentless interior styled similarly to metro trains. In 1978, seven units were built, numbered from 009 to 015. In 1979, five more units were produced, numbered 016 to 020, with unit EW58-018 being presented at the Poznań International Fair. In 1980, the final eight units, numbered 021 to 028, were delivered.

In 1984, for testing purposes related to the development of the EW60 units, thyristor pulse start was installed in the EW58-018sa car, while the old resistance start was retained in the second motor car. The tests concluded in 1988, determining that the system was not suitable for mass implementation, and it was not adopted for the EW60 units. The test unit remained at the Railway Scientific and Technical Centre until 1992.