A method and device for maintaining a multi-channel serial communication interface of a power distribution terminal

Abstract

The present invention discloses a serial port maintenance method and a serial port maintenance device for a multi-channel serial port communication power distribution terminal, comprising the following steps: storing a configuration file having a protocol feature library and a baud rate applicable library in a main control board MCU, initializing and allocating each serial port communication interface, matching the message baud rate and protocol type received by the serial port communication interface with the baud rate and protocol type allocated by the serial port communication interface initialization, parsing the message when all matches are consistent, transmitting the parsed message to a master station, adjusting the serial port communication interface state, and storing the acquired information of the serial port communication interface in the main control board MCU for archiving. The present invention directly and conspicuously notifies the distribution network operation and maintenance personnel of the serial port state by adjusting the indicator lights to different states after serial port communication, thereby improving the detection rate of communication defects of terminal equipment, shortening the closed-loop cycle for solving problems, reducing the patrol and maintenance workload of the distribution network operation and maintenance on the terminal device, and then efficiently and safely solving the hidden dangers of the problem.

Description

Technical Field

[0001] The present invention relates to the technical field of power distribution terminal communication, and in particular to a method and a device for maintaining a multi-channel serial port communication interface of a power distribution terminal. Background Art

[0002] The distribution network is an important part of the power system. As an important public infrastructure, it is characterized by many sites and scattered locations, and the distribution network operation and maintenance workload is large. Nowadays, the power grid pays more and more attention to the stability of power supply, and the operation and maintenance of the distribution network is even more important. The current operation and maintenance work requires fixed-period patrols and full-coverage monitoring of distribution terminal equipment, but this model has the disadvantages of large patrol and maintenance workload, lack of focus, and lack of pertinence; at the same time, given that the communication anomalies of the terminal equipment are not easy to find, and the information indication is not clear, the distribution network operation and maintenance has the following problems: low defect detection rate in terminal equipment communication, unstable results, and long closed-loop cycle for solving problems. The long closed-loop cycle for solving problems is because the terminal manufacturer needs to be notified to go to the site for maintenance, and the terminal manufacturer needs to rewrite the configuration file after replacing the serial port and restart the device; in this case, the distribution network operation and maintenance needs to apply for a power outage operation permit. Under the condition of ensuring the stability of the power supply of the power grid, the distribution terminal link increases the closed-loop cycle for solving problems. Summary of the invention

[0003] In order to solve the technical problems mentioned in the background technology, the present invention provides a method and a device for maintaining a multi-channel serial communication interface of a power distribution terminal.

[0004] The present invention adopts the following technical solution: a method for maintaining a multi-channel serial communication interface of a power distribution terminal, comprising the following steps:

[0005] S100; a configuration file having a protocol feature library and a baud rate applicable library is stored in the main control board MCU; the protocol feature library includes a variety of protocol message feature codes in advance; the baud rate applicable library determines the applicable baud rate range of various different frequencies;

[0006] S200; initialize and allocate each serial communication interface, each serial communication interface is initialized to a protocol type in the associated protocol feature library, and the baud rate is set to the baud rate applicable to the library with the lowest frequency baud rate;

[0007] S300; start the serial communication interface to start receiving messages, the message contains an uncertain baud rate and protocol type, and the message is sent continuously and uninterruptedly within a unit time;

[0008] S400; the baud rate and protocol type of the message received by the serial communication interface are matched with the baud rate and protocol type assigned by the serial communication interface initialization, and if the two cannot completely match, the serial communication interface is adjusted to state one; when both match, the message received by the serial communication interface is parsed, and if the parsing is completed, the parsed message is transmitted to the master station, and the serial communication interface is adjusted to state two;

[0009] If the analysis cannot be completed, adjust the serial communication interface to state three;

[0010] S500: Store the obtained status value of the serial communication interface in the main control board MCU for archiving.

[0011] Furthermore, in S400, matching the message baud rate and protocol received by the serial communication interface with the protocol type and baud rate initially allocated by the serial communication interface includes:

[0012] S4001: Compare the baud rate assigned by the serial communication interface for initialization, and if the two frequencies are inconsistent, automatically adjust the baud rate of the serial communication interface to the baud rate of the upper frequency in the baud rate applicable library, until it is adjusted to the baud rate of the maximum frequency in the baud rate applicable library;

[0013] S4002: When the serial communication interface is adjusted to be consistent with the baud rate of the received message, the received message protocol type is traversed and searched with each type of protocol in the protocol feature library to match the same protocol type; when the match is successful, the protocol type associated with the serial communication interface is adjusted to be consistent with the received message protocol type.

[0014] Furthermore, in step S400, if the two cannot completely match each other, the serial communication interface is adjusted to state 1, including

[0015] S4003: If in S4001, the baud rate of the serial communication interface after polling adjustment is the baud rate of the maximum frequency in the baud rate applicability library, but is still inconsistent with the baud rate of the message received by the serial communication interface, or the received message protocol type is traversed and searched with each type of protocol in the protocol feature library, and no match is found for the same protocol type, then the indicator light corresponding to the serial communication interface is adjusted to green, indicating that the serial communication interface cannot be matched normally.

[0016] Further, in the S400, when both are matched, the message received by the serial communication interface is parsed, and if the parsing is completed, the parsed message is transmitted to the master station, and the serial communication interface is adjusted to state two; if the parsing cannot be completed, the serial communication interface is adjusted to state three, including: after the protocol message identification module successfully matches the protocol data processing module, the protocol data processing algorithm is called to parse the received message within a unit time, convert it into the data format required by the master station, transmit it to the master station after the parsing is completed, and adjust the indicator light corresponding to the serial communication interface to a yellow light, indicating that the serial communication interface is in normal use;

[0017] If the parsing fails within a unit time, the message is repeatedly parsed within the set time range; if the message received by the serial communication interface still cannot be parsed after repeated parsing, the indicator light corresponding to the serial communication interface is adjusted to red, indicating that the serial communication interface is abnormally unavailable.

[0018] Furthermore, the present invention also provides a multi-channel serial communication interface maintenance device for a power distribution terminal, comprising: a main control board MCU, a communication interface module, a serial port management module and a protocol management module;

[0019] The main control board MCU stores a configuration file having a protocol feature library and a baud rate applicable library; the protocol feature library includes a plurality of protocol message feature codes in advance; the baud rate applicable library determines the applicable baud rate ranges of a plurality of different frequencies;

[0020] The communication interface module is connected to the main control board MCU and includes multiple serial communication interfaces; each serial communication interface supports both RS232 and RS485 dual-channel interfaces;

[0021] The serial port management module is connected to the communication interface module and includes a serial port allocation management module, a serial port working condition analysis module and a serial port baud rate identification module;

[0022] The serial port allocation management module is used to initialize and allocate each serial port communication interface, each serial port communication interface is initialized to a protocol type in the associated protocol feature library, and the baud rate is set to the baud rate with the lowest frequency in the baud rate applicable library;

[0023] The serial port working condition analysis module is used to control the indicator light group connected to each serial port communication interface;

[0024] The serial port baud rate identification module is used to compare the baud rate of the message received by the serial port communication interface with the baud rate assigned by the serial port communication interface during initialization. If the frequencies of the two are inconsistent, the baud rate of the serial port communication interface is automatically adjusted to the baud rate of the previous order frequency until the frequencies of the two are consistent; if the baud rate of the serial port communication interface after polling adjustment is the baud rate of the maximum frequency in the baud rate applicable library, but is still inconsistent with the baud rate of the message received by the serial port communication interface, the serial port working condition analysis module is notified to adjust the indicator light corresponding to the serial port communication interface, indicating that the serial port communication interface cannot be matched normally;

[0025] The protocol management module is connected to the communication interface module and includes a protocol message identification module and a protocol data processing module;

[0026] The protocol message identification module, when the serial port baud rate identification module adjusts the serial port communication interface to be consistent with the baud rate of the received message, searches the received message protocol type and each type of protocol in the protocol feature library to match the same protocol type; when the match is successful, adjusts the protocol type associated with the serial port communication interface to be consistent with the received message protocol type;

[0027] The protocol data processing module is used to call the protocol data processing algorithm to parse the received message within a unit time after the protocol message identification module successfully matches, convert it into the data format required by the master station, transmit it to the master station after the parsing is completed, and notify the serial port working condition analysis module to adjust the indicator light corresponding to the serial port communication interface to indicate that the serial port communication interface is in normal use;

[0028] It also includes a timer module. If the analysis fails within a unit time, the timer module is called to perform repeated analysis within N unit times; if the protocol data processing module still cannot parse the message received by the serial communication interface after repeated analysis, the serial port working condition analysis module is notified to adjust the indicator light corresponding to the serial communication interface, indicating that the serial communication interface is abnormal and unavailable.

[0029] Furthermore, each indicator light group includes three status indicator lights: yellow, green and red, and the yellow flashing indicates that the corresponding serial communication interface is in normal use; the green is always on when the serial communication interface cannot be matched normally; and the red is always on when the serial communication interface is abnormal and unavailable.

[0030] Compared with the prior art, the advantages of the present invention are: the multi-channel serial port communication interface maintenance method and maintenance device designed by the present invention for the distribution terminal directly and prominently notify the distribution network operation and maintenance personnel of the serial port status by adjusting the indicator lights to different states after serial port communication, thereby improving the detection rate of terminal equipment communication defects, shortening the closed-loop cycle for solving problems, reducing the inspection and maintenance workload of the distribution network operation and maintenance on the terminal devices, and then efficiently and safely solving the hidden dangers of the problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A flow chart of a method for maintaining a multi-channel serial communication interface of a power distribution terminal according to the present invention;

[0032] Figure 2 It is a block diagram of the multi-channel serial communication interface maintenance device of the power distribution terminal of the present invention. DETAILED DESCRIPTION

[0033] In order to facilitate those skilled in the art to understand the technical solution of the present invention, further description will be given below with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention.

[0034] In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may be implemented without these specific details. In addition, in the following description, descriptions of known structures and techniques are omitted to avoid unnecessary confusion of concepts of the present invention.

[0035] like Figure 1 As shown, the multi-channel serial communication interface maintenance method of the power distribution terminal designed by the present invention includes the following steps:

[0036] S100; a configuration file having a protocol feature library and a baud rate applicable library is stored in the main control board MCU; the protocol feature library includes a variety of protocol message feature codes in advance; the baud rate applicable library determines the applicable baud rate range of various different frequencies;

[0037] S200; initialize and allocate each serial communication interface, each serial communication interface is initialized to a protocol type in the associated protocol feature library, and the baud rate is set to the baud rate applicable to the library with the lowest frequency baud rate;

[0038] S300; start the serial communication interface to start receiving messages, the message contains an uncertain baud rate and protocol type, and the message is sent continuously and uninterruptedly within a unit time. During the specific implementation, the message is set to be sent to the serial communication interface once every 3 seconds.

[0039] S400; the baud rate and protocol type of the message received by the serial communication interface are matched with the baud rate and protocol type assigned by the serial communication interface initialization, and if the two cannot completely match, the serial communication interface is adjusted to state one; when both match, the message received by the serial communication interface is parsed, and if the parsing is completed, the parsed message is transmitted to the master station, and the serial communication interface is adjusted to state two;

[0040] The specific implementation includes comparing the baud rate of the message received by the serial communication interface with the baud rate assigned by the serial communication interface during initialization. If the two frequencies are inconsistent, the baud rate of the serial communication interface is automatically adjusted to the baud rate of the previous order frequency in the baud rate applicable library until it is adjusted to the baud rate of the maximum frequency in the baud rate applicable library.

[0041] When the serial communication interface is adjusted to be consistent with the baud rate of the received message, the received message protocol type is traversed and searched with each type of protocol in the protocol feature library to match the same protocol type; when the match is successful, the protocol type associated with the serial communication interface is adjusted to be consistent with the received message protocol type.

[0042] If the baud rate of the serial communication interface after polling adjustment is the baud rate of the maximum frequency in the baud rate applicable library, but is still inconsistent with the baud rate of the message received by the serial communication interface, or the received message protocol type is traversed and searched with each type of protocol in the protocol feature library, and the same protocol type cannot be matched, then the indicator light corresponding to the serial communication interface is adjusted to green, that is, state one, indicating that the serial communication interface cannot be matched normally.

[0043] After the protocol is matched successfully, the protocol data processing algorithm is called to parse the received message within a unit time and convert it into the data format required by the master station. After the parsing is completed, it is transmitted to the master station and the indicator light corresponding to the serial communication interface is adjusted to yellow, indicating that the serial communication interface is in normal use;

[0044] If the parsing fails within the unit time, the message is parsed repeatedly within the set time range, as shown in the figure above. During specific implementation, the time range can be set to continuously receive messages within 240 seconds. If the message received by the serial communication interface still cannot be parsed after repeated parsing within 240 seconds, the indicator light corresponding to the serial communication interface is adjusted to red, that is, state three, indicating that the serial communication interface is abnormal and unavailable.

[0045] S500: Store the obtained status value of the serial communication interface in the main control board MCU for archiving.

[0046] like Figure 2 As shown, the present invention also provides a multi-channel serial port communication interface maintenance device for a power distribution terminal. When the device is running, it will monitor the serial port communication status in real time. When the serial port communication in use is found to be abnormal, it will directly and conspicuously notify the distribution network operation and maintenance personnel by adjusting the indicator light. The device includes: a main control board MCU, a communication interface module, a serial port management module and a protocol management module;

[0047] The main control board MCU stores a configuration file with a protocol feature library and a baud rate application library; the protocol feature library includes a variety of protocol message feature codes in advance; the baud rate application library determines the applicable baud rate range of a variety of different frequencies; the role of writing the configuration file is to register the supported protocol type in the protocol identification module, that is, the protocol type required for the site. For example, in the power distribution project, the main station is generally IEC101 protocol, and the communication of other devices connected to the station is MODBUS protocol, then the configuration file is written to the terminal device to register and enable the two protocols of IEC101 and MODBUS. The baud rate range is generally set to 4800, 9600, 19200 and 38400 according to site needs.

[0048] The communication interface module is connected to the main control board MCU and includes multiple serial communication interfaces; each serial communication interface supports both RS232 and RS485 dual-channel interfaces;

[0049] The serial port management module is connected to the communication interface module and includes a serial port allocation management module, a serial port working condition analysis module and a serial port baud rate identification module;

[0050] The serial port allocation management module is used to initialize and allocate each serial port communication interface. Each serial port communication interface is initialized to a protocol type in the associated protocol feature library, and the baud rate is set to the baud rate with the lowest frequency in the baud rate applicable library. For example, serial port 1 is allocated to the first protocol in the configuration file, such as IEC101 protocol, and serial port 2 is allocated to the second protocol in the configuration file, such as MODBUS protocol. At this time, the working status of all serial ports is normal and available.

[0051] The serial port working condition analysis module is used to control the indicator light group connected to each serial port communication interface;

[0052] The serial port baud rate identification module is used to compare the baud rate of the message received by the serial port communication interface with the baud rate assigned by the serial port communication interface during initialization. If the two frequencies are inconsistent, the baud rate of the serial port communication interface is automatically adjusted to the baud rate of the previous order frequency until the two frequencies are consistent; if the baud rate of the serial port communication interface after polling adjustment is the baud rate of the maximum frequency in the baud rate applicable library, but is still inconsistent with the baud rate of the message received by the serial port communication interface, the serial port working condition judgment module is notified to adjust the indicator light corresponding to the serial port communication interface, indicating that the serial port communication interface cannot be matched normally. In specific implementation, the baud rate can be initialized to 4800 first, and then enter the data receiving and sending stage. Determine whether data is received. If data is not received, the module sets the serial port baud rate to 9600 and then repeats the execution. If data is still received, it is set to 19200 in sequence until it is set to 38400 and still not received, and the serial port working condition state is set to unable to match normally.

[0053] The protocol management module is connected to the communication interface module and includes a protocol message identification module and a protocol data processing module;

[0054] The protocol message identification module, when the serial port baud rate identification module adjusts the serial port communication interface to be consistent with the received message baud rate, traverses and searches the received message protocol type and each type of protocol in the protocol feature library to match the same protocol type; when the match is successful, adjust the protocol type associated with the serial port communication interface to be consistent with the received message protocol type; for example, the IEC101 protocol has two obvious characteristics of long and short frames: the long frame starts with 0x68 and ends with 0x16; the short frame starts with 0x10 and ends with 0x16. The MODBUS protocol is characterized by the first byte data value being 1-255, the second byte being the data length, and the last two bytes being CRC check. When the serial port receives data, the protocol message identification module searches the protocol feature library, and the protocol type of the current message can be retrieved through the comparison algorithm. The protocol message identification module returns the matching success and protocol type information. When the protocol type of the current message cannot be retrieved, the protocol identification module returns the matching failure.

[0055] The protocol data processing module is used to call the protocol data processing algorithm to parse the received message within a unit time after the protocol message identification module successfully matches. It is generally set to send a message once every 3 seconds, convert it into the data format required by the master station, transmit it to the master station after the analysis is completed, and notify the serial port working condition analysis module to adjust the indicator light corresponding to the serial port communication interface to indicate that the serial port communication interface is in normal use;

[0056] It also includes a timer module. If the analysis fails within a unit time, the timer module is called to perform repeated analysis within N unit time. If the protocol data processing module still cannot parse the message received by the serial communication interface after repeated analysis, the serial port working condition analysis module is notified to adjust the indicator light corresponding to the serial communication interface, indicating that the serial communication interface is abnormal and unavailable. 240 seconds is a field experience value and can be adjusted according to the actual situation on site.

[0057] In specific implementation, each indicator light group includes three status indicators, yellow, green and red. The yellow indicator light flashes when the corresponding serial communication interface is in normal use; the green indicator light is always on when the serial communication interface cannot be matched normally; and the red indicator light is always on when the serial communication interface is abnormal and unavailable.

[0058] To sum up, the multi-channel serial port communication interface maintenance method and maintenance device designed by the present invention for the power distribution terminal can directly and prominently notify the distribution network operation and maintenance personnel of the serial port status by adjusting the indicator lights to different states after serial port communication. After a serial port fails, the communication line can be directly switched to any serial port with a lit yellow indicator light. The terminal device can automatically identify and use the new serial port without modifying the configuration file, thereby improving the detection rate of communication defects in terminal equipment, shortening the closed-loop cycle for solving problems, reducing the inspection and maintenance workload of the distribution network operation and maintenance on the terminal devices, and then efficiently and safely solving hidden dangers of problems.

[0059] The above embodiments are merely descriptions of preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for maintaining a multi-channel serial communication interface of a power distribution terminal, characterized in that: The following steps are involved: S100; a configuration file having a protocol feature library and a baud rate applicable library is stored in the main control board MCU; The protocol feature library contains a variety of protocol message feature codes in advance; the baud rate application library determines the applicable baud rate ranges of various frequencies; S200; initialize and allocate each serial communication interface, each serial communication interface is initialized to a protocol type in the associated protocol feature library, and the baud rate is set to the baud rate applicable to the library with the lowest frequency baud rate; S300; start the serial communication interface to start receiving messages, the message contains an uncertain baud rate and protocol type, and the message is sent continuously and uninterruptedly within a unit time; S400; the baud rate and protocol type of the message received by the serial communication interface are matched with the baud rate and protocol type assigned by the serial communication interface initialization, and if the two cannot completely match, the serial communication interface is adjusted to state one; when both match, the message received by the serial communication interface is parsed, and if the parsing is completed, the parsed message is transmitted to the master station, and the serial communication interface is adjusted to state two; If the analysis cannot be completed, adjust the serial communication interface to state three; S500; the obtained status value of the serial communication interface is stored in the main control board MCU for archiving; In S400, matching the baud rate and protocol type of the message received by the serial communication interface with the baud rate and protocol type initially allocated by the serial communication interface includes: S4001: Compare the baud rate assigned by the serial communication interface for initialization, and if the two frequencies are inconsistent, automatically adjust the baud rate of the serial communication interface to the baud rate of the upper frequency in the baud rate applicable library, until it is adjusted to the baud rate of the maximum frequency in the baud rate applicable library; S4002: When the serial communication interface is adjusted to be consistent with the baud rate of the received message, the received message protocol type is searched and matched with each type of protocol in the protocol feature library to find the same protocol type; when the match is successful, the protocol type associated with the serial communication interface is adjusted to be consistent with the received message protocol type; In the step S400, if the two cannot completely match each other, adjusting the serial communication interface to state 1 includes: S4003: If in S4001, the baud rate of the serial communication interface after polling adjustment is the baud rate of the maximum frequency in the baud rate applicable library, but it is still inconsistent with the baud rate of the message received by the serial communication interface, or the received message protocol type is traversed and searched with each type of protocol in the protocol feature library, and the same protocol type cannot be matched, then the indicator light corresponding to the serial communication interface is adjusted to green, indicating that the serial communication interface cannot be matched normally; In the S400, when both match, the message received by the serial communication interface is parsed, and if the parsing is completed, the parsed message is transmitted to the master station, and the serial communication interface is adjusted to state two; if the parsing cannot be completed, the serial communication interface is adjusted to state three, including: after the baud rate of the message received by the serial communication interface is matched with the baud rate in the baud rate applicable library, and the received message protocol type is matched with the protocol in the protocol feature library to obtain the same protocol type, the protocol data processing algorithm is called to parse the received message within a unit time, convert it into the data format required by the master station, transmit it to the master station after the parsing is completed, and adjust the indicator light corresponding to the serial communication interface to a yellow light, indicating that the serial communication interface is in normal use; If the parsing fails within a unit time, the message is repeatedly parsed within the set time range; if the message received by the serial communication interface still cannot be parsed after repeated parsing, the indicator light corresponding to the serial communication interface is adjusted to red, indicating that the serial communication interface is abnormally unavailable.

2. A multi-channel serial communication interface maintenance device for a power distribution terminal, characterized in that: include: Main control board MCU, communication interface module, serial port management module and protocol management module; The main control board MCU stores a configuration file having a protocol feature library and a baud rate applicable library; The protocol feature library contains a variety of protocol message feature codes in advance; the baud rate application library determines the applicable baud rate ranges of various frequencies; The communication interface module is connected to the main control board MCU and includes multiple serial communication interfaces; each serial communication interface supports both RS232 and RS485 dual-channel interfaces; The serial port management module is connected to the communication interface module and includes a serial port allocation management module, a serial port working condition analysis module and a serial port baud rate identification module; The serial port allocation management module is used to initialize and allocate each serial port communication interface, each serial port communication interface is initialized to a protocol type in the associated protocol feature library, and the baud rate is set to the baud rate with the lowest frequency in the baud rate applicable library; The serial port working condition analysis module is used to control the indicator light group connected to each serial port communication interface; The serial port baud rate identification module is used to compare the baud rate of the message received by the serial port communication interface with the baud rate assigned by the serial port communication interface during initialization. If the frequencies of the two are inconsistent, the baud rate of the serial port communication interface is automatically adjusted to the baud rate of the previous order frequency until the frequencies of the two are consistent; if the baud rate of the serial port communication interface after polling adjustment is the baud rate of the maximum frequency in the baud rate applicable library, but is still inconsistent with the baud rate of the message received by the serial port communication interface, the serial port working condition analysis module is notified to adjust the indicator light corresponding to the serial port communication interface, indicating that the serial port communication interface cannot be matched normally; The protocol management module is connected to the communication interface module and includes a protocol message identification module and a protocol data processing module; The protocol message identification module, when the serial port baud rate identification module adjusts the serial port communication interface to be consistent with the baud rate of the received message, searches the received message protocol type and each type of protocol in the protocol feature library to match the same protocol type; When the match is successful, the protocol type associated with the serial communication interface initialization is adjusted to be consistent with the received message protocol type; The protocol data processing module is used to call the protocol data processing algorithm to parse the received message within a unit time after the protocol message identification module successfully matches, convert it into the data format required by the master station, transmit it to the master station after the parsing is completed, and notify the serial port working condition analysis module to adjust the indicator light corresponding to the serial port communication interface to indicate that the serial port communication interface is in normal use; The device also includes a timer module. If the analysis fails within a unit time, the timer module is called to perform repeated analysis within N unit times. If the protocol data processing module still cannot parse the message received by the serial communication interface after repeated analysis, the serial port working condition analysis module is notified to adjust the indicator light corresponding to the serial communication interface, indicating that the serial communication interface is abnormal and unavailable.

3. The multi-channel serial communication interface maintenance device of the power distribution terminal according to claim 2, characterized in that: Each indicator light group includes three status indicators: yellow, green, and red. If the yellow indicator light flashes, the corresponding serial communication interface is in normal use; if the green indicator light is always on, the serial communication interface cannot be matched normally; and if the red indicator light is always on, the serial communication interface is abnormal and unavailable.

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