PKP classification system (Polish locomotive designation) is a system of assigning letters and numbers to series and individual locomotives used by the PKP

Polskie Koleje Panstwowe

is the dominant railway operator in Poland.The company was founded when the former state-owned operator was divided into several units based on the requirements laid down by the European Union...

 - Polish

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 national railroad operator.

The system was introduced in 1923, shortly after Poland regained her independence (1918), when the Polish railroads inherited a variety of German, Austrian and Russian steam locomotives, each with its own type convention. The adopted solution allows telling the locomotive type (passenger/freight/mixed), wheel arrangement

Wheel arrangement

In rail transport, a wheel arrangement is a system of classifying the way in which wheels are distributed beneath a locomotive.. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and connections, with the adopted notations varying by country...

, origin and some other information from the type designation. After World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 a similar system was also adapted for diesel and electric locomotives.

First letter

• E - electric locomotive
  Electric locomotive
  An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or an on-board energy storage device...
  
   
• S - diesel locomotive
  Diesel locomotive
  A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...
  
   

Locomotives

• P - passenger locomotive
• T - freight locomotive
• U - mixed-traffic locomotive ( - universal)
• M - shunting locomotive

Electric multiple units

• W - for high platforms
• N - for both high and low platforms
• D - for long distance traffic

Diesel railcars and multiple units

• D - for long-distance traffic
• N - for suburban traffic
• R - special purpose (mobile workshops, emergency use etc.)
• A - railbus
  Railbus
  A railbus is a very lightweight type passenger rail vehicle that shares many aspects of their construction with a bus, usually having a bus, or modified bus body, and having four wheels on a fixed base, instead of on bogies...
  
   

Electric locomotives

• 01-14 - four axles, Bo-Bo
  Bo-Bo
  A Bo-Bo or Bo′Bo′ is a locomotive with two independent four-wheeled bogies with all axles powered by individual traction motors...
  
  , direct current
  Direct current
  Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
  
  , 3 kV
• 15-19 - four axles, Bo-Bo
  Bo-Bo
  A Bo-Bo or Bo′Bo′ is a locomotive with two independent four-wheeled bogies with all axles powered by individual traction motors...
  
  , alternating current
  Alternating current
  In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
  
  
• 20-34 - six axles, Co-Co, direct current
  Direct current
  Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
  
  , 3 kV
• 35-39 - six axles, Co-Co, alternating current
  Alternating current
  In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
  
  
• 40-49 - other types

In the case of electric and diesel locomotives consisting of two cars, the letters A and B were added after the serial number for each car but the number is still the same for both the cars.

Electric multiple units

• 51-64 - three car sets, direct current
  Direct current
  Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
  
  , 3 kV
• 65-69 - three car sets, alternating current
  Alternating current
  In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
  
  
• 70-74 - four car sets, direct current
  Direct current
  Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
  
  , 3 kV
• 75-79 - four car sets, alternating current
  Alternating current
  In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
  
  
• 80-89 - single electric car, any current
• 90-93 - two car sets, direct current
  Direct current
  Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
  
  , 800 V
• 94-99 - other types

Every car in a multiple unit has got it own suffix,
s - (silnikowy) propelled car
d - (doczepny) trailer car
r - (rozrządczy) cab car, non-propelled
If there are more than one car it is identified with letter a or b, for example a typical 3 car unit En-57 contains car:
- EN57-830ra
- EN57-830s
- EN57-830rb
that means a unit contains a propelled car between two cab cars.
In the latest constructions the suffixes are reduced to simple a, b, c, d and further.

Diesel locomotives

• 01-09 - mechanical transmission, single steering
• 10-14 - mechanical transmission, multiple steering
• 15-24 - hydraulic transmission, single steering
• 25-29 - hydraulic transmission, multiple steering
• 30-39 - electric transmission, single steering
• 40-49 - electric transmission, multiple steering

Diesel railcars and multiple units

• 51-59 mechanical transmission, single steering
• 60-69 mechanical transmission, multiple steering
• 70-79 hydraulic or hydrauli-mechanical transmission, single steering
• 80-89 hydraulic transmission, multiple steering
• 90-94 electric transmission, single steering
• 95-99 electric transmission, multiple steering

First letter

The upper case letter means:

• P - fast train locomotive
• O - mixed/stopping train traffic ( - passenger)
• T - freight locomotive

Second letter

Second letter (lower case) indicates the wheel arrangement

Wheel arrangement

In rail transport, a wheel arrangement is a system of classifying the way in which wheels are distributed beneath a locomotive.. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and connections, with the adopted notations varying by country...

, in increasing order of the number of driving axles.

• a - one driving axle, any number of unpowered axles
• b - 0-4-0
  0-4-0
  Under the Whyte notation for the classification of steam locomotives, 0-4-0 represents one of the simplest possible types, that with two axles and four coupled wheels, all of which are driven...
  
  
• c - 2-4-0
  2-4-0
  Under the Whyte notation for the classification of steam locomotives, 2-4-0 represents the wheel arrangement of two leading wheels on one axle, four powered and coupled driving wheels on two axles, and no trailing wheels....
  
   or 0-4-2
  0-4-2
  Under the Whyte notation for the classification of steam locomotives, 0-4-2 represents the wheel arrangement with no leading wheels, four powered and coupled driving wheels on two axles, and two trailing wheels on one axle...
  
  
• d - 4-4-0
  4-4-0
  Under the Whyte notation for the classification of steam locomotives, 4-4-0 represents the wheel arrangement of four leading wheels on two axles , four powered and coupled driving wheels on two axles, and no trailing wheels...
  
   or 0-4-4
  0-4-4
  Under the Whyte notation for the classification of steam locomotives, 0-4-4 represents the wheel arrangement of no leading wheels, four powered and coupled driving wheels on two axles, and four trailing wheels on two axles...
  
  
• e - 2-4-2
  2-4-2
  Under the Whyte notation for the classification of steam locomotives, 2-4-2 represents the wheel arrangement of two leading wheels on one axle, four powered and coupled driving wheels on two axles, and two trailing wheels on one axle...
  
  
• f - 4-4-2
  4-4-2 (locomotive)
  Under the Whyte notation for the classification of steam locomotives, 4-4-2 represents the wheel arrangement of four leading wheels on two axles , four powered and coupled driving wheels on two axles, and two trailing wheels on one axle...
  
   or 2-4-4
  2-4-4
  In Whyte notation, a 2-4-4 is a steam locomotive with two unpowered leading wheels followed by four powered driving wheels and four unpowered trailing wheels.-Equivalent classifications:Other equivalent classifications are:...
  
  
• g - two driving axles, more than three unpowered axles,
• h - 0-6-0
  0-6-0
  Under the Whyte notation for the classification of steam locomotives, 0-6-0 represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles, and no trailing wheels...
  
  
• i - 2-6-0
  2-6-0
  Under the Whyte notation for the classification of steam locomotives, 2-6-0 represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, six powered and coupled driving wheels on three axles, and no trailing wheels. This arrangement is commonly called a Mogul...
  
   or 0-6-2
  0-6-2
  Under the Whyte notation for the classification of steam locomotives, 0-6-2 represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles, and two trailing wheels on one axle...
  
  
• k - 4-6-0
  4-6-0
  Under the Whyte notation for the classification of steam locomotives, 4-6-0 represents the wheel arrangement of four leading wheels on two axles in a leading truck, six powered and coupled driving wheels on three axles, and no trailing wheels. This wheel arrangement became the second-most popular...
  
   or 0-6-4
  0-6-4
  Under the Whyte notation for the classification of steam locomotives, 0-6-4 represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles, and four trailing wheels on two axles....
  
  
• l - 2-6-2
  2-6-2
  Under the Whyte notation for the classification of steam locomotives, 2-6-2 represents the wheel arrangement of two leading wheels, six coupled driving wheels and two trailing wheels.Other equivalent classifications are:...
  
  
• m - 4-6-2
  4-6-2
  4-6-2, in the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles , six powered and coupled driving wheels on three axles, and two trailing wheels on one axle .These locomotives are also known as Pacifics...
  
  
• n - 2-6-4
  2-6-4
  Under the Whyte notation for the classification of steam locomotives, a 2-6-4 locomotive has two leading wheels, six coupled driving wheels and four trailing wheels...
  
  
• o - three driving axles, more than three unpowered axles
• p - 0-8-0
  0-8-0
  Under the Whyte notation for the classification of steam locomotives, 0-8-0 represents the wheel arrangement of no leading wheels, eight powered and coupled driving wheels on four axles, and no trailing wheels...
  
  
• r - 2-8-0
  2-8-0
  Under the Whyte notation for the classification of steam locomotives, 2-8-0 represents the wheel arrangement of two leading wheels on one axle , eight powered and coupled driving wheels on four axles, and no trailing wheels...
  
   or 0-8-2
  0-8-2
  Under the Whyte notation for the classification of steam locomotives, 0-8-2 represents the wheel arrangement of no leading wheels, eight powered and coupled driving wheels on four axles, and two trailing wheels on one axle ....
  
  
• s - 4-8-0
  4-8-0
  Under the Whyte notation for the classification of steam locomotives, 4-8-0 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and no trailing wheels. The type was nicknamed the Mastodon or Twelve-wheeler in North America....
  
   or 0-8-4
  0-8-4
  Under the Whyte notation for the classification of steam locomotives, 0-8-4 represents the wheel arrangement of no leading wheels, eight powered and coupled driving wheels on four axles, and four trailing wheels on two axles ....
  
  
• t - 2-8-2
  2-8-2
  Under the Whyte notation for the classification of steam locomotives, 2-8-2 represents the wheel arrangement of two leading wheels on one axle , eight powered and coupled driving wheels on four axles, and two trailing wheels on one axle...
  
  
• u - four driving axles, more than two unpowered axles
• w - 0-10-0
  0-10-0
  Under the Whyte notation for the classification of steam locomotives, 0-10-0 represents the wheel arrangement of no leading wheels, ten powered and coupled driving wheels on five axles, and no trailing wheels...
  
  
• y - 2-10-0
  2-10-0
  Under the Whyte notation for the classification of steam locomotives, 2-10-0 represents the wheel arrangement of two leading wheels on one axle, ten powered and coupled driving wheels on five axles, and no trailing wheels...
  
  
• z - five driving axles, more than one unpowered axle

-=-=-=-=-

• x - narrow gauge, all axle arrangements ("x" also could mean six driving axles, but such locomotives were not used in Poland)

Third letter

In the case of tank engines, the letters designating the type of engine and the wheel arrangement are separated by a 'K'. Thus TKt48 is a 2-8-2 tank of Polish design introduced in 1948.

Number

• 1-9 - German
  Germany
  Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
  
   production steam engine
• 10-19 - Austria
  Austria
  Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
  
  n production steam engine
• 20-99 - Polish
  Poland
  Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
  
   steam engine, number stood for the last two digits of the year in which the type was approved for production
• 100 - private steam engine that is not in PKP stock
• 101-199 - Other foreign steam engine, acquired by PKP
  Polskie Koleje Panstwowe
  is the dominant railway operator in Poland.The company was founded when the former state-owned operator was divided into several units based on the requirements laid down by the European Union...
  
   between 1918 and 1939
• 200-299 - Other foreign production steam engine, acquired by PKP
  Polskie Koleje Panstwowe
  is the dominant railway operator in Poland.The company was founded when the former state-owned operator was divided into several units based on the requirements laid down by the European Union...
  
   after 1945

Serial numbers

Following the letters and numbers described above, the serial number of each individual locomotive is stated. This consists of several digits, separated from the type designation characters by a dash.

First number

• First number of tender
  Tender locomotive
  A tender or coal-car is a special rail vehicle hauled by a steam locomotive containing the locomotive's fuel and water. Steam locomotives consume large quantities of water compared to the quantity of fuel, so tenders are necessary to keep the locomotive running over long distances. A locomotive...
  
   classification described water capacity in cubic meters.

Letter

• Letter described the number of axles, i.e.:
  • C - three axles
  • D - four axles

Second number

• This referred to the year of construction, so number 23 means the construction was approved in 1923.

An example

A tender

Tender locomotive

A tender or coal-car is a special rail vehicle hauled by a steam locomotive containing the locomotive's fuel and water. Steam locomotives consume large quantities of water compared to the quantity of fuel, so tenders are necessary to keep the locomotive running over long distances. A locomotive...

 numbered 22D23 can carry up to 22 m³ of water, has four axles, and its construction was approved in 1923.

See also

• PKP
  Polskie Koleje Panstwowe
  is the dominant railway operator in Poland.The company was founded when the former state-owned operator was divided into several units based on the requirements laid down by the European Union...