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Fail-Safe Data Transmission System

To provide the ability of fail-safe like ATC with the use of fail-safe LSI that is developed for ATC (Automatic Train Control system

Fail -Safe data transmission method of control command is composed of two transmission CPUs and FS (Fail-Safe)-LSI. Two CPUs transmit the control command with converting it to serial data transmission signal in each individual transmission CPU, and receives the data transmitted by another CPU. Each CPU writes the transmitting data and data received into the FS-LSI. FS-LSI compares these data, and generates the relay control signal if they are exactly the same. If they are different, FS-LSI stops the relay control signal without delay, AC.AMP amplifies the relay control signal, and switches the relay that controls the output of control commands for the transmission line. Moreover, FS-LSI is applied the special circuit as the relay control signal will be stopped without delay if a failure occurs in FS-LSI itself.

  • * Note: In some countries, "ATC" here is also called "ATP (Automatic Train Protection)".

Diagram of Faile-Safe Data Transmission System

High Speed Data Transmission with Electric Wires

Electric wire cables are used for high-speed data transmission (3.2Mbps), which are easier to handle than optical fiber cables.

 Wire cablesOptical fiber cables
Handlingeasywith care
(no special requirement and tools)
with care
(special requirement and tools)