It contains a description of  basic performance functions and features of implementation of a microprocessor system of interlocking of marshaling yard of Northern yard of Krasny Liman station of Donetskay railway.

Presently relay systems of automatic marshaling yards interlocking is implemented at major part of sorting yards of Ukraine (YAI). One of the main objectives in development of railway transport is creation of MP MYAI with the subsequent integration into ACS switch yards (ACS of CC).

Today the works of implementation of MP YAI are carried out at Northern yard of Krasny Liman station of the Donetsk railway . Start up and commissioning are planned for 2007. Northern Yard has two humping and two detaching ways. The car yard has 32 ways for accumulation of formed rakes. Ways of a car yard are integrated in six butches Simultaneous detaching of uncoupling is made only on one of ways humping. Head of shift is yard master, who has effectively subordinated following stuff: yard officer on duty, teams of shunters, yard conductors.

The system designer is the «Zheldoravtomatika» – scientific and production enterprise (Kharkov) which performs complete complex of works from design to commissioning of microprocessor systems of railway automatic equipment (microprocessor interlocking of switches and signals of stations of the main line and industrial designation, the centralized traffic control, automatic crossing signaling, etc.).

All logical functions of yard interlocking of this system are performed by hard- and software of industrial computers and PLC and direct links of track side assets are provided by existing standard diagrams of control and supervision. Speed gauges, distance gauges, weight gauges,occupancy sensors related to track side assets are connected directly to PLC by mean of signal converters of i/o modules. The system has high safety and fail safety and is build so that violation in its operation resulted no critical failure. MP YAI shall contain serially manufactured assets with open data transfer protocols.MP YAI performs following functions:

• switching of points by route of uncoupled cars rolling down;
• monitoring of filling of ways of a car yard;
• automatic recording of a course of TP;
• communication with ACS of CC; monitoring of a status of signalling devices, switching and interlocking (SCB);
• supervision of operation of track side and post assets;
• archiving of process of uncoupling and possibility of viewing of records within 30 days;
• fixing and issuance of data of  to duty personal about splitting and regaining of uncoupling;
• creating of protocol of executed detachment.

Device control is carried out by officer on duty of yard from a post No. 1 and operators of yard who are at posts No. 2-7. Panels with the built-in graphic terminals are installed in all posts  intended for monitoring of process of detachment, diagnostics of devices and obtaining service information.Post No1 is equipped with AWP of yard duty officer (AWP of DIOP) and electrical engineer (AWP EE),  joint with system and control cabinets by means of electronic switcher. AWPs (industrial computers) serve for a dialog with the operator and allow to receive complete and single-digit display of a situation about location uncoupling on tracking net, status of controlled objects in graphic and color modes for acceptance of operational decisions on detaching process control.Control of detaching process is provided in routine, scheduled and for future in automatic modes. Yard duty officer, whenever required, have a possibility switch points manually using handles of control board. In routine mode route of track of uncoupling is provided by yard duty officer individually of each uncoupling.In scheduled mode there is possibility to assign of routes for each uncoupling of pulled train. In automatic mode marshaling list comes from ACS-MS to AWP of DIOP and whether required is processed by yard duty officer. After finishing of train splitting automatically compiled protocol is printed. Fig.1 shows graphic image of AWP EE. Screen of AWP consists of status bar and yard videogram field.Status bar of AWP-EE contains data about station, system time, date, as well as fly-menu, reflecting status of assets and archive. PLC menu contains diagnostic data of controller status in still frame pictures, in color mode reflecting operation/failure i/o modules, source of power, central processor.When opening menu «Switch point» appears (Fig. 2) info about all switch points: position, operation mode, occupancy/vacancy of switch point section and time switching. «Traffic light» menu allows obtaining information regarding to status and operation capability of each «traffic light». Thus electric engineer controls of operation of velocity meters, distance gauges, spot sensors of car traveling, and car retarders of 1…3 of break positions.«Archive» menu contains information for the 30 days of system operation. Comfortable interface and detail diagnostic data provide possibility to electric engineer to remove a fail promptly.Displays of automated workplaces of Yard duty officer and the electric engineer screen tracking development of hump yard, floor assets and check lights displaying a mode of functioning of YAI, status of controlled relays, and also storage unit. Alternatively to microprocessing systems the memory of relay systems is limited.Memory of MP-YAI of Northern Yard of Krasny Liman station can store data of all uncouplings of train. Storage indicator is placed at top corner of yard videogram.Besides standard functions of yard interlocking MP-YAI provides more effective tracking of «alien» cars, i.e. cars traveled out of routine assignment, and simultaneously sends such data for printing. There is also provision for simultaneous tracking by main, branch and dispatch point switchers by means of cell indicator of each switch point.Rather then relay systems MP YAI allows to perform following functions: monitoring of occupancy of rail tracks, real velocity of uncouplings at each breaking position, time of turn of switch point, and pressure in air main of retarder, defining of weight of uncoupling.For future it is planned to providing of fixed speed of uncoupling outcomes from each breaking position.In bottom part of yard videogram there is a field indicating failures of system. assets and post devices along with accompanying with voice messages.Graphic screening of automatic workplace of yard duty officer by many feature id similar to AWP of EE. It differs because duty officer do not need the scope of diagnostic data, set in developed menu. That is why the status bar of AWP of DIOP contains data of marshaling list, time and date as well as archive. Station videogram at yard duty officer contains information regarding YAI, storage unit, monitoring devices of main zone (ICD), and also mode of printing device.Functions of yard interlocking are provided on microprocessor base in compliance with typical solutions for design of yard actuators MG-47 and MG-48. Yard interlocking uses PLCs of the Schneider Electric firm, differing by high reliability, productivity and successfully functioning on the railways «Ukrzaliznytsa» and in PUC «Kievsky metropolyten» as microprocessor devices.Relay equipment and units are installed on standard racks with cross switch erection system. PLC are placed in control cabinets (CC) CC-1 and CC-2 contain PLC of Quantum series, providing processing of outcoming signals, logic of yard interlocking, and control of output circuits. PLC of Momentum series are placed in CC-3, they performs, collection of information coming from speed, distance gauges, spot sensors and transfer of these data to CC-1 and graphic interfaces of control boards. CC-1 supplies data to AWP of duty officer and electric engineer.Concept software environment is applied for programming of PLC of Schneider Electric design which supports programming languages of IEC 61131-3.International Standard. Software of MP YAI represents block structure of functional program units.Industrial networks Modbus TCP/IP and Modbus Plus are used as data transfer channels. Controllers and network adapters are the items which supports Modbus Plus. The bus of a network consists of the twisted pair cable of the shielded cable which passes on the trunk between two serial nodes. Nodes are connected to a cable by means of couplers, Quantum controllers are connected directly to cable of the bus of a network via specialized communication port Modbus Plus. For increase of high-speed performance of system the separate Modbus Plus network is selected for each post with the appropriate controllers in CC-3. CCs and AWPs are connected to Modbus TCP/IP network.Implementation of a microprocessor system of yard interlocking will allow to improve considerably quality of control TP processing capability of a yard due to highly effective processing, output of necessary data and data exchange with other ACS.

Article is published in «Automation in industry» magazine, January, 2007