PURPOSE: An RS485-converter is provided to increase effectiveness through a data analysis when inspecting and maintaining an automatic door of a railway vehicle by using the RS485-converter which has information according to time. CONSTITUTION: A micro controller unit (MCU) obtains the initial setup and information of a Wi-Fi module. A watch integrated circuit (IC) stores time information by updating a time by the MCU. A charging circuit for the watch IC maintains time information even in a state where a vehicle power is blocked. A connection part is connected to a cable in order to connect to each door control unit in an RS485 controller. A power circuit converts a vehicle power into a power which is used in the inside of a converter. [Reference numerals] (AA) Charging circuit; (BB) Power supply circuit; (CC) Wi-Fi module; (DD) RS485 controller; (EE) Connection unit
