Distributed network system for serial communication

Abstract

The invention relates to the technical field of distributed network systems, and discloses a serial communication distributed network system, which comprises a distributed network system constructed by an upper computer module, a network host module and a lower computer module, and is characterized in that the lower computer module comprises an industrial field instrument, a sensor and controller equipment; according to the distributed network system for serial communication, the photoelectric coupler and the operational amplifier are arranged, so that the influence of external interference signals on the network host module and the lower computer equipment can be effectively prevented, data errors and system faults caused by interference are reduced, the accuracy and the stability of data transmission are ensured, the signal strength can be enhanced, and the reliability of data transmission is improved. The anti-interference capability of signals is improved, under the condition of long-distance communication or a large number of lower computers, the signals may be attenuated, and the communication quality is reduced, the signals can be amplified by using the operational amplifier, the strength of the signals in the transmission process is ensured, and thus the reliability of the system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of distributed network systems, in particular to a distributed network system of serial communication. Background Art

[0002] In the field of industrial automation, signal acquisition, monitoring and control of on-site instruments, sensors, controllers and other equipment are crucial links. With the continuous expansion of industrial production scale and the continuous advancement of technology, traditional centralized control systems have been unable to meet the needs of complex industrial sites.

[0003] The distributed network system of serial communication came into being, which can connect devices distributed in different locations to realize data collection, transmission and control. This system has the advantages of high flexibility, strong scalability and low cost, and is suitable for various industrial sites.

[0004] However, in practical applications, the distributed network system of serial communication also faces some challenges. For example, due to the complex industrial field environment, there are various interference sources, which may affect the quality of data transmission; the communication protocols between different devices may be different, and protocol conversion is required; the stability and reliability of the system also need to be guaranteed to ensure the safety and efficiency of industrial production. For this reason, we propose a distributed network system of serial communication. Summary of the invention

[0005] The object of the present invention is to provide a distributed network system of serial communication to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions: a distributed network system for serial communication, comprising a distributed network system constructed by a host computer module, a network host module and a slave computer module;

[0007] The lower computer module includes instruments, sensors and controller equipment at the industrial site;

[0008] The network host module is a core part, which has multiple RS485 interfaces and one RS232 interface, and is responsible for communicating with the lower computer and the upper computer, and storing data. Photoelectric couplers are installed at the RS485 and RS232 interfaces of the network host module. The input signal is first isolated by the photoelectric coupler, and then enters the network host module for processing. The output signal is also isolated by the photoelectric coupler before being sent out, so as to achieve signal isolation, which can effectively prevent external interference signals from entering the network host module through the communication line, and improve the stability and reliability of the system. Operational amplifiers are installed at the RS485 and RS232 interfaces of the network host module, and the input signal is first amplified by the operational amplifier, and then enters the network host module for processing. The output signal can also be amplified by the operational amplifier before being sent out, which can effectively improve the signal strength and anti-interference ability, and ensure the stability and reliability of the network.

[0009] The host computer module is used for data processing, monitoring and control command issuance;

[0010] The lower computer module needs to be partitioned first, and an address code is set in each area, so that the network host can accurately identify and distinguish different lower computers. After the lower computer module is partitioned, the lower computers in each area are networked through the set address code and connected to an RS485 interface of the network host. The network host communicates point-to-point with the upper computer module through the RS232 interface.

[0011] Preferably, the lower computer module is partitioned based on geographical location, and an on-site survey is conducted on the industrial site to understand the distribution of each lower computer equipment, determine the different areas of the factory building and the different sections of the production line for division, and according to the survey results, the lower computer equipment located in the same geographical area is grouped into one partition and numbered to implement partitioning operations, which can facilitate subsequent management and identification.

[0012] Preferably, the sensor is responsible for collecting various physical quantities at the industrial site, wherein the sensor converts the collected physical signals into electrical signals to provide a source of raw data for subsequent data processing.

[0013] Preferably, the controller device has an input and output interface for receiving signals from sensors and sending control instructions to actuators. The controller device processes the input signals according to a preset control algorithm, including performing logical judgment and PID control to achieve precise control of the industrial process. The controller device has a communication function, and the controller device is connected to the network host module to facilitate data exchange with the network host module, receive control instructions from the host computer module and feedback its own status information.

[0014] Preferably, the instruments at the industrial site are used to display and record the numerical values ​​of various physical quantities, which is convenient for operators to monitor and judge. The measurement data can be sent to the network host module through the controller device, and the configuration information and control instructions of the network host module can be received through the controller device to realize remote parameter setting and control, which is more convenient for staff to operate.

[0015] Preferably, the RS482 interface part of the network host module sets a lower communication baud rate according to the distance after networking and the data of the lower computer device. The network host module reads the data of each lower computer device in the area in turn and stores the data in RAM, reasonably arranges the order and events of reading each area, ensures the accuracy and completeness of the data, and receives control instructions and parameter setting information from the upper computer, and forwards them to the corresponding lower computer device.

[0016] Preferably, the RS232 interface part of the network host module performs point-to-point communication with the upper computer module. Since the distance is very short, a higher baud rate is used to transmit all the data stored in the RAM to the upper computer module at high speed. At the same time, the data sent by the upper computer module is received and stored in the RAM first, waiting to be forwarded to the lower computer module.

[0017] Preferably, after receiving the data from the lower computer module uploaded by the network host module, the upper computer module processes, analyzes and displays the data to realize monitoring of the industrial site, and sends downward control instructions and parameter setting information as needed, first stores these data in the RAM of the network host module, and then forwards them to the lower computer module by the network host module to realize control and parameter setting of the industrial field equipment.

[0018] Preferably, the Modbus communication protocol is adopted between the network host module and the upper computer module and the lower computer module to ensure the stability and reliability of communication between them. The network host module adopts a retransmission mechanism and error code feedback to promptly handle errors in the communication process, further improve the reliability of communication, establish a system monitoring mechanism, and monitor the operating status of the network host module in real time, including CPU usage, memory occupancy, and communication status. When an abnormal situation occurs, an alarm is issued in time to facilitate troubleshooting.

[0019] Compared with the prior art, the present invention provides a distributed network system for serial communication, which has the following beneficial effects:

[0020] 1. The distributed network system of serial communication can effectively prevent the influence of external interference signals on the network host module and the lower computer equipment through the setting of optocouplers and operational amplifiers, reduce data errors and system failures caused by interference, ensure the accuracy and stability of data transmission, and enhance the strength of the signal and improve the anti-interference ability of the signal. In the case of long-distance communication or a large number of lower computers, the signal may attenuate, resulting in a decrease in communication quality. By using operational amplifiers, the signal can be amplified to ensure the strength of the signal during transmission, thereby improving the reliability of the system.

[0021] 2. The distributed network system of the serial communication and the distributed network structure enable the system to be flexibly expanded according to actual needs. New slave devices can be easily added by simply connecting them to the corresponding interface of the network host module, setting the address code and networking. This flexibility enables the system to adapt to industrial sites of different sizes and changing production needs. The design of multiple RS485 interfaces and one RS232 interface enables the network host module to communicate with different types of slave and host computers. Whether it is a traditional instrument, sensor, or a new controller device, it can be connected to the system through an appropriate interface to realize data collection and control. This compatibility enhances the scalability of the system and facilitates users to choose appropriate equipment according to actual conditions.

[0022] 3. In this serial communication distributed network system, data reading between regions is synchronous and concurrent, which means that the network host module can read data from the lower computers in multiple regions at the same time, greatly improving the efficiency of data acquisition. Compared with the traditional sequential reading method, synchronous and concurrent reading can reduce the time of data acquisition and improve the response speed of the system. The network host module and the upper computer use a higher baud rate for communication, which can achieve high-speed data transmission. This enables the upper computer to obtain real-time data from the lower computer in a timely manner, and conduct rapid analysis and processing, thereby improving the real-time performance of the system.

[0023] 4. The distributed network system of serial communication adopts serial communication. Compared with the parallel communication, the number of cables and the cost are lower. At the same time, since the lower-level equipment can be distributed in different locations, the complexity and cost of wiring are reduced. The modular design of the system makes maintenance more convenient. If a lower-level equipment fails, it can be repaired or replaced separately without affecting the operation of the entire system. In addition, the stability and reliability of the network host module are improved, which also reduces the maintenance workload and cost of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the system of the present invention. DETAILED DESCRIPTION

[0025] like Figure 1 As shown, the present invention provides a technical solution: a distributed network system of serial communication, including a distributed network system constructed by a host computer module, a network host module and a slave computer module;

[0026] The lower computer module includes instruments, sensors and controller equipment at the industrial site;

[0027] As the core part, the network host module has multiple RS485 interfaces and one RS232 interface, which is responsible for communicating with the lower and upper computers and storing data. Photoelectric couplers are installed at the RS485 and RS232 interfaces of the network host module. The input signal is first isolated by the photoelectric coupler, and then enters the network host module for processing. The output signal is also isolated by the photoelectric coupler before being sent out to achieve signal isolation, which can effectively prevent external interference signals from entering the network host module through the communication line, and improve the stability and reliability of the system. Operational amplifiers are installed at the RS485 and RS232 interfaces of the network host module. The input signal is first amplified by the operational amplifier, and then enters the network host module for processing. The output signal can also be amplified by the operational amplifier before being sent out, which can effectively improve the signal strength and anti-interference ability, and ensure the stability and reliability of the network.

[0028] The host computer module is used for data processing, monitoring and control command issuance;

[0029] The lower computer module needs to be partitioned first, and the address code is set in each area, which can facilitate the network host to accurately identify and distinguish different lower computers. After the lower computer module is partitioned, the lower computers in each area are networked through the set address code and connected to an RS485 interface of the network host. The network host communicates point-to-point with the upper computer module through the RS232 interface.

[0030] The lower computer module is partitioned based on geographical location, and conducts on-site surveys on the industrial site to understand the distribution of each lower computer equipment, determine the different areas of the factory building and the different sections of the production line, and according to the survey results, classify the lower computer equipment located in the same geographical area into a partition and number them to implement partition operations, which can facilitate subsequent management and identification.

[0031] Sensors are responsible for collecting various physical quantities at industrial sites. The sensors convert the collected physical signals into electrical signals, including but not limited to temperature sensors collecting temperature data, pressure sensors collecting pressure data, and flow sensors collecting fluid flow data, providing the original data source for subsequent data processing.

[0032] The controller device has an input and output interface for receiving signals from sensors and sending control instructions to actuators. The controller device processes the input signals according to a preset control algorithm, including logical judgment and PID control, to achieve precise control of the industrial process. The controller device has a communication function, and the controller device is connected to the network host module to facilitate data exchange with the network host module, receive control instructions from the host computer module and feedback its own status information.

[0033] Instruments at industrial sites are used to display and record the values ​​of various physical quantities, which is convenient for operators to monitor and judge. The measurement data can be sent to the network host module through the controller device, and the configuration information and control instructions of the network host module can be received through the controller device to realize remote parameter setting and control, which is more convenient for operators to operate.

[0034] The RS482 interface of the network host module sets a lower communication baud rate, such as 9600bps, according to the distance after networking and the data of the lower-level device. The network host module reads the data of each lower-level device in the area in turn and stores the data in RAM, reasonably arranges the order and events of reading each area to ensure the accuracy and integrity of the data, and receives control instructions and parameter setting information from the upper computer and forwards them to the corresponding lower-level device.

[0035] The RS232 interface of the network host module communicates with the upper computer module point-to-point. Due to the short distance, a higher baud rate is used, such as 115299bps or higher, to transmit all data stored in the RAM to the upper computer module at high speed. At the same time, it receives the data sent by the upper computer module and stores it in RAM first, waiting to be forwarded to the lower computer module.

[0036] After receiving the data uploaded by the network host module from the lower computer module, the upper computer module processes, analyzes and displays it to realize the monitoring of the industrial site. According to the control instructions and parameter setting information sent downward as needed, these data are first stored in the RAM of the network host module, and then forwarded by the network host module to the lower computer module to realize the control and parameter setting of the industrial field equipment.

[0037] The Modbus communication protocol is used between the network host module and the upper computer module and the lower computer module to ensure the stability and reliability of communication between them. The network host module adopts a retransmission mechanism and error code feedback to promptly handle errors in the communication process, such as checksum errors and timeout errors, to further improve the reliability of communication. A system monitoring mechanism is established to monitor the operating status of the network host module in real time, including CPU usage, memory occupancy, and communication status. When an abnormal situation occurs, an alarm is issued in time to facilitate troubleshooting.

[0038] The above generally describes the present invention in detail, but it is obvious to a person skilled in the art that some modifications or improvements can be made to the present invention. Therefore, modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. A distributed network system for serial communication, characterized in that: It includes a distributed network system constructed by a host computer module, a network host module and a slave computer module; The lower computer module includes instruments, sensors and controller equipment at the industrial site; The network host module is the core part, and has multiple RS485 interfaces and one RS232 interface, which is responsible for communicating with the lower computer and the upper computer and storing data. Photoelectric couplers are installed at the RS485 and RS232 interfaces of the network host module. The input signal is first isolated by the photoelectric coupler, and then enters the network host module for processing. The output signal is also isolated by the photoelectric coupler before being sent out to achieve signal isolation. Operational amplifiers are installed at the RS485 and RS232 interfaces of the network host module. The input signal is first amplified by the operational amplifier, and then enters the network host module for processing. The output signal can also be amplified by the operational amplifier before being sent out; The host computer module is used for data processing, monitoring and control command issuance; The lower computer module needs to be partitioned first and an address code is set in each area. After the lower computer module is partitioned, the lower computers in each area are networked through the set address code and connected to an RS485 interface of the network host. The network host communicates point-to-point with the upper computer module through the RS232 interface.

2. A distributed network system for serial communication according to claim 1, characterized in that: The lower computer module is partitioned based on geographical location, conducts on-site surveys on the industrial site, understands the distribution of each lower computer equipment, determines the division of different areas of the factory building and different sections of the production line, and according to the survey results, classifies the lower computer equipment located in the same geographical area into a partition and number them to realize partition operation.

3. A distributed network system for serial communication according to claim 1, characterized in that: The sensor is responsible for collecting various physical quantities at the industrial site, wherein the sensor converts the collected physical signals into electrical signals.

4. A distributed network system for serial communication according to claim 1, characterized in that: The controller device has an input and output interface for receiving signals from sensors and sending control instructions to actuators. The controller device processes the input signals according to a preset control algorithm, including logical judgment and PID control. The controller device has a communication function, and the controller device is connected to the network host module to facilitate data exchange with the network host module, receive control instructions from the host computer module and feedback its own status information.

5. A distributed network system for serial communication according to claim 1, characterized in that: The instrument at the industrial site is used to display and record the numerical values ​​of various physical quantities, and can send the measurement data to the network host module through the controller device, and can also receive the configuration information and control instructions of the network host module through the controller device to realize remote parameter setting and control.

6. A distributed network system for serial communication according to claim 1, characterized in that: The RS482 interface part of the network host module sets a lower communication baud rate according to the distance after networking and the data of the lower computer device. The network host module reads the data of each lower computer device in the area in turn and stores the data in RAM, reasonably arranges the order and events of reading each area, and receives control instructions and parameter setting information from the upper computer, and forwards them to the corresponding lower computer device.

7. A distributed network system for serial communication according to claim 1, characterized in that: The RS232 interface part of the network host module performs point-to-point communication with the upper computer module. Due to the short distance, a higher baud rate is used to transmit all the data stored in the RAM to the upper computer module at high speed. At the same time, the data sent by the upper computer module is received and stored in the RAM first, waiting to be forwarded to the lower computer module.

8. A distributed network system for serial communication according to claim 1, characterized in that: After receiving the data uploaded by the network host module from the lower computer module, the upper computer module processes, analyzes and displays the data, and sends control instructions and parameter setting information downward as needed. These data are first stored in the RAM of the network host module, and then forwarded to the lower computer module by the network host module.

9. A distributed network system for serial communication according to claim 1, characterized in that: The Modbus communication protocol is used between the network host module and the upper computer module and the lower computer module. The network host module adopts a retransmission mechanism and error code feedback to promptly handle errors in the communication process, establish a system monitoring mechanism, and monitor the operating status of the network host module in real time, including CPU usage, memory occupancy, and communication status. When an abnormal situation occurs, an alarm is issued in a timely manner.

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