Electronically controlled pneumatic brakes
Encyclopedia
Electronically controlled pneumatic brakes are a type of modern railway braking system
which offer improved performance compared to traditional pneumatic (compressed air) brakes.
Greater intervals between brake tests are also likely because of the ability of ECP brakes to self-diagnose which should generate large cost savings that will help pay for the system to be installed.
The benefits are better control of braking, less equipment wear from pushing and pulling between cars, shorter stopping distance and improved headways.
. The Fortescue line also places the two brake pipes and single control/power cables on one side of the wagons only, as trains operate only as block loads and the wagons are not normally reversed. Having the wires on one side avoids the need for crew to stoop under the coupling, as would be the case with the normal configuration where the hose and wire cross under the coupling.
In the case of the Fortescue railway, the new ECP brakes are incompatible in several ways.
began operating on October 11, 2007 with the Norfolk Southern Railway
. Testing of ECP braking on Spoornet
's Richards Bay heavy haul line in South Africa
was also expected to begin by the end of 2007, for service in 2009. January 24, 2008:- first trials on BNSF BNSF retrofit 300 Power River coal cars with Wabtec
ECP-4200. ECP braking is also being tested in Australia. May 2008: new Fortescue
iron ore railway has ECP. September 2008: Canadian Pacific Railway
has begun testing ECP-equipped coal trains on its coal haul route in British Columbia
. November 2008: According to RGI the two systems from NYAB and Wabtec are meant to be interoperable, but testing to confirm this has yet to be carried out. Federal rules limit normal air brake inspection to once every 1600 kilometers, but with ECP this increases to 5600 kilometres, allowing a coast-to-coast return trip on a single inspection at home base.
Brake (railway)
Brakes are used on the cars of railway trains to enable deceleration, control acceleration or to keep them standing when parked. While the basic principle is familiar from road vehicle usage, operational features are more complex because of the need to control multiple linked carriages and to be...
which offer improved performance compared to traditional pneumatic (compressed air) brakes.
Overview
Traditional systems apply the brakes sequentially from car to car along the train, meaning that up to two minutes can elapse between operation of the control valve on the leading locomotive and the application of brakes on the last car of a 150-wagon freight train. In contrast, ECP braking uses electronic controls which make it possible to activate air-powered brakes on all the wagons throughout the train at the same time. Applying the brakes uniformly and instantaneously in this way gives better train control, shortens the stopping distances, and leads to a lower risk of derailment or of coupling breakage.Testing
During initial testing the ECP equipment had software glitches, and problems from the ingress of moisture into the equipement. These have now been resolved.Greater intervals between brake tests are also likely because of the ability of ECP brakes to self-diagnose which should generate large cost savings that will help pay for the system to be installed.
The benefits are better control of braking, less equipment wear from pushing and pulling between cars, shorter stopping distance and improved headways.
Control and power
When first developed, ECP brakes needed a number of wires along the train to control solenoids on each wagon to release the brakes, and were not considered economic for freight. This has changed with the introduction of electronic controls, allowing data to be transmitted by two-conductor wire or radio from the loco to a microprocessor on each car, where locally powered valves hold the desired pressure in each brake cylinder.Use on Fortescue Railway
ECP can use axle-generated power or wire-distributed power. The Fortescue railway uses wire-distributed power at 200 V DCDirect 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...
. The Fortescue line also places the two brake pipes and single control/power cables on one side of the wagons only, as trains operate only as block loads and the wagons are not normally reversed. Having the wires on one side avoids the need for crew to stoop under the coupling, as would be the case with the normal configuration where the hose and wire cross under the coupling.
Compatibility
ECP brakes by the two manufacturers are meant to be mutually compatible.In the case of the Fortescue railway, the new ECP brakes are incompatible in several ways.
- The wagon-to-wagon pipes are straight and are on one side of the wagon only, and do not cross over to the other side underneath the coupling.
- Wagons are one-sided, though locomotives are dual-sided for flexibility. The wagons are one-sided to suit a rotary tipplerRotary car dumperA rotary car dumper or wagon tippler is a mechanism used for unloading certain railroad cars such as hopper cars, gondolas or lorries . It holds the rail car to a section of track and rotates the track and car together to dump out the contents. Used with gondola cars, it is making open hopper cars...
.
Progress and examples
1990s- first trials on BN in the 1990s TSM of Kansas City operated more than eight coal and intermodal trains using their "EABS" ECP for BN, CP and Amtrak. TSM was purchased by Wabco in 1998. The first ECP-equipped Norfolk Southern train in the United StatesUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
began operating on October 11, 2007 with the Norfolk Southern Railway
Norfolk Southern Railway
The Norfolk Southern Railway is a Class I railroad in the United States, owned by the Norfolk Southern Corporation. With headquarters in Norfolk, Virginia, the company operates 21,500 route miles in 22 eastern states, the District of Columbia and the province of Ontario, Canada...
. Testing of ECP braking on Spoornet
Spoornet
Transnet Freight Rail is a South African rail transport company, formerly known as Spoornet. It was part of 'South African Railways and Harbours', a state-controlled organisation that employed hundreds of thousands of people for decades from the first half of the 20th century and was widely...
's Richards Bay heavy haul line in South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
was also expected to begin by the end of 2007, for service in 2009. January 24, 2008:- first trials on BNSF BNSF retrofit 300 Power River coal cars with Wabtec
Wabtec
Wabtec Corporation is an American company formed by the merger of the Westinghouse Air Brake Company and MotivePower Industries Corporation in 1999....
ECP-4200. ECP braking is also being tested in Australia. May 2008: new Fortescue
Fortescue Metals Group
Fortescue Metals Group is an Australian iron ore mining company. The company has holdings of more than 87,000 km² in the Pilbara region of Western Australia making it the largest tenement holder in the state. It is listed as FMG on the Australian Securities Exchange .In 2008, the group loaded...
iron ore railway has ECP. September 2008: Canadian Pacific Railway
Canadian Pacific Railway
The Canadian Pacific Railway , formerly also known as CP Rail between 1968 and 1996, is a historic Canadian Class I railway founded in 1881 and now operated by Canadian Pacific Railway Limited, which began operations as legal owner in a corporate restructuring in 2001...
has begun testing ECP-equipped coal trains on its coal haul route in British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
. November 2008: According to RGI the two systems from NYAB and Wabtec are meant to be interoperable, but testing to confirm this has yet to be carried out. Federal rules limit normal air brake inspection to once every 1600 kilometers, but with ECP this increases to 5600 kilometres, allowing a coast-to-coast return trip on a single inspection at home base.
Distributed power
Distributed power is a system where locomotives are coupled in the middle and/or end of a heavy train and remotely controlled originally via radio from the locomotive in the front. Amongst other advantages, this reduces coupling stresses in long and heavy trains. The ECP wiring can also be used to control these intermediate locomotives.Parameters
- Standard = Association of American RailroadsAssociation of American RailroadsThe Association of American Railroads is an industry trade group representing primarily the major freight railroads of North America . Amtrak and some regional commuter railroads are also members...
S-4200 - Train Length = 3658 m (12,001 ft) maximum
- Wagons (Network Devices) = 180
- Wired Distributed Power (WDP) = 230 V DC
See also
- Railway air brake
- New York Air Brake (equipment supplier)New York Air BrakeThe New York Air Brake Corporation, located in Watertown, New York, is a manufacturer of air brake and train control systems for the railroad industry worldwide.-History:-Establishment 1876-1900:...
- Wabtec (equipment supplier)WabtecWabtec Corporation is an American company formed by the merger of the Westinghouse Air Brake Company and MotivePower Industries Corporation in 1999....