A relay assembly comprises a vital relay used in a vital circuit and configured to be rack-installed in an equipment room in a railroad case or a railroad housing for providing a modular solid-state current-limiting. The relay assembly further comprises a plurality of vital relay contacts to which a current flow is restricted by a single supply solid-state current limiter. The relay assembly further comprises a relay socket base assembly coupled to the vital relay. The relay socket base assembly includes a relay socket base including a plurality of vital relay contact prongs, a plug assembly including a plurality of printed circuit board (PCB) mounted contact terminals, and a plurality of contact terminals that provide a connection between the plurality of vital relay contact prongs and the plurality of printed circuit board (PCB) mounted contact terminals. The relay assembly further comprises an ancillary electrical control module.

A relay assembly comprises a vital relay used in a vital circuit and configured to be rack-installed in an equipment room in a railroad case or a railroad housing for providing a modular solid-state current-limiting. The relay assembly further comprises a plurality of vital relay contacts to which a current flow is restricted by a single supply solid-state current limiter. The relay assembly further comprises a relay socket base assembly coupled to the vital relay. The relay socket base assembly includes a relay socket base including a plurality of vital relay contact prongs, a plug assembly including a plurality of printed circuit board (PCB) mounted contact terminals, and a plurality of contact terminals that provide a connection between the plurality of vital relay contact prongs and the plurality of printed circuit board (PCB) mounted contact terminals. The relay assembly further comprises an ancillary electrical control module.

A system and method for virtual block stick circuits is presented. The present disclosure implements specialized algorithms adapted to determine the true status of a virtual block based on multiple inputs from different perspectives. In one embodiment, the system can use the far house perspective of that virtual track segment and the PTC hazard for the near virtual track segment directly adjacent to the near house uses the near house perspective of that virtual track segment. For the middle virtual track segments, the near house perspectives of the middle virtual track segments are held ‘TRUE’ if they are already ‘TRUE’ when the train first enters the block, using stick circuits for the near house perspective of the middle track circuits. The vital application can then indicate the true state of the virtual track segment as occupied (FALSE), to protect the train from trains that follow.

An interface adapter for controlling a track-side object of a railway installation includes an analog input from an external source and an analog output to drive an electromechanical relay circuit. A bidirectional digital communication interface communicates digital data including first digital data transmitted and second digital data received. An analog-to-digital converter coupled to the analog input is configured to generate a first digital signal representing the electrical input. A digital-to-analog converter coupled to the analog output is configured to generate the electrical output in response to a second digital signal. A power supply supplies electrical power to the digital-to-analog converter. A programmable logic control circuit includes a control program configured to produce the first digital data from the first digital signal, transmit the first digital data using the digital communication interface, process the second digital data, and produce the second digital signal in response to the second digital data.

An interface adapter for controlling a track-side object of a railway installation includes an analog input from an external source and an analog output to drive an electromechanical relay circuit. A bidirectional digital communication interface communicates digital data including first digital data transmitted and second digital data received. An analog-to-digital converter coupled to the analog input is configured to generate a first digital signal representing the electrical input. A digital-to-analog converter coupled to the analog output is configured to generate the electrical output in response to a second digital signal. A power supply supplies electrical power to the digital-to-analog converter. A programmable logic control circuit includes a control program configured to produce the first digital data from the first digital signal, transmit the first digital data using the digital communication interface, process the second digital data, and produce the second digital signal in response to the second digital data.

A system and method for virtual block stick circuits is presented. The present disclosure implements specialized algorithms adapted to determine the true status of a virtual block based on multiple inputs from different perspectives. In one embodiment, the system can use the far house perspective of that virtual track segment and the PTC hazard for the near virtual track segment directly adjacent to the near house uses the near house perspective of that virtual track segment. For the middle virtual track segments, the near house perspectives of the middle virtual track segments are held ‘TRUE’ if they are already ‘TRUE’ when the train first enters the block, using stick circuits for the near house perspective of the middle track circuits. The vital application can then indicate the true state of the virtual track segment as occupied (FALSE), to protect the train from trains that follow.

A system and method for virtual block operational status control with long block time delay is presented. The present disclosure can advantageously increase the capacity and safety of the existing railroad track infrastructure used by the railroads by determining whether a virtual block is healthy or unhealthy. The long block mode can provide a coarse granularity on the presence of a train. In virtual block mode, the system can implement a finer granularity so the virtual aspects of the sub blocks can be realized. The present disclosure provides a long block mode that can provide the system an opportunity to analyze the potential tradeoffs between granularity and reliability by determining which mode (virtual block or long block) is best utilized in a given situation. The system can operate by default in long block mode and ignore the virtual block capabilities until absolutely needed.

A method for commanding a railway level crossing protection system comprising: a) activating a railway signal preventing a train from driving beyond a level crossing; b) detecting an incoming train approaching the level crossing and measuring a speed of said incoming train; c) calculating a waiting time, as a function of the train's measured speed; d) waiting until expiration of the calculated waiting time and, once said waiting time expires, sending an order to commute the protection system into the protected state; and e) querying the state of the protection system and if said protection system is found to have commuted into the protected state, deactivating said railway signal, and maintaining said railway signal in the activated state otherwise.

A method for commanding a railway level crossing protection system comprising: a) activating a railway signal preventing a train from driving beyond a level crossing; b) detecting an incoming train approaching the level crossing and measuring a speed of said incoming train; c) calculating a waiting time, as a function of the train's measured speed; d) waiting until expiration of the calculated waiting time and, once said waiting time expires, sending an order to commute the protection system into the protected state; and e) querying the state of the protection system and if said protection system is found to have commuted into the protected state, deactivating said railway signal, and maintaining said railway signal in the activated state otherwise.

A system and method for virtual block stick circuits is presented. The present disclosure implements specialized algorithms adapted to determine the true status of a virtual block based on multiple inputs from different perspectives. In one embodiment, the system can use the far house perspective of that virtual track segment and the PTC hazard for the near virtual track segment directly adjacent to the near house uses the near house perspective of that virtual track segment. For the middle virtual track segments, the near house perspectives of the middle virtual track segments are held ‘TRUE’ if they are already ‘TRUE’ when the train first enters the block, using stick circuits for the near house perspective of the middle track circuits. The vital application can then indicate the true state of the virtual track segment as occupied (FALSE), to protect the train from trains that follow.