目前，我國大多數軌道列車邏輯控制系統都采用有觸點的控制方式，隨著對列車性能要求的提高，這種有觸點控制方式暴露出電路結構復雜、可靠性與靈活性差等一系列弊端。

    邏輯控制單元LCU(Logic Control Unit)使用現代化的電子元件來取代原來電力機車上由電磁線圈和機械觸點構成的繼電器。相比傳統的列車控制電路，LCU控制電路采用完全的雙冗余設計，大幅度地提高了系統可靠性和響應速度；此外還增加了故障記錄單元，提供全程的故障實時記錄，有助于維護人員快速維修和維護；上位機軟件可以隨時更改邏輯設計，如果有控制邏輯或者延時參數等修改的需求，重新下載一遍控制邏輯即可，無需更換硬件設備或者重新布線；產品還增加了緊急環路開關模塊，一旦出現極端的故障情況，也不會導致列車控制嚴重癱瘓。

    綜上，以邏輯控制網絡來替代原有的邏輯電路是未來列車邏輯控制電路的發展趨勢。LCU可以大幅度提高列車控制電路的整體可靠性，降低車輛維護難度，減少檢修工作量，從而實現列車車輛控制電路系統技術的升級。

    At present, most of domestic railway logic control system uses relay control mode，as the improvement requirements of train performance, relay control mode exposes a series of drawbacks such as over complicated circuit structure, poor reliability and poor flexibility.

    The logic control unit (LCU) use modern electronic components to replace the original electric locomotive composed of electromagnetic coil and mechanical relay. Compared with the traditional train control circuit, LCU uses full dual redundancy design, greatly improved the reliability and response speed of system;embedded a fault recording unit, providing fault real-time recording of the entire process which is helpful to a quick repairment and maintenance; PC software can change the logic design at any time, if there is a delay or parameter needs to modify such as demand, all you need is download it again ,no need to change the hardware devices or rewiring; the product also embedded the emergency loop switch module , once comes to a extreme failure, it will not lead to a serious train control paralysis.

    In summary, logical control networks replace the original logic circuit is the  trend of future train logic control circuit . LCU can greatly improve the reliability of the whole train control circuit, reduce vehicle maintenance difficulty, reduce maintenance workload, so as to realize the upgrade of train circuit control system .