WO2023228357A1

WO2023228357A1 - Programmable logic controller, control system, data collection method, and program

Info

Publication number: WO2023228357A1
Application number: PCT/JP2022/021567
Authority: WO
Inventors: 知洋古川
Original assignee: 三菱電機株式会社
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2023-11-30
Also published as: JPWO2023228357A1

Abstract

In a programmable logic controller (10), a communication unit (17) communicates with external equipment (30). A program execution unit (130) executes a user program for controlling a controlled object. A device data collection unit (140) collects a plurality of sets of device data stored in a plurality of devices, which are storage areas referenced by the program execution unit (130), and associates and stores, in a first buffer, each of the plurality of sets of device data with information about the time at which the set of device data was collected. A line data collection unit (150) collects a plurality of sets of line data that satisfy collection conditions from the data communicated by the communication unit (17), and associates and stores, in a second buffer, the plurality of sets of line data with information about the time at which each set of line data was communicated. A data output unit (170) outputs the plurality of sets of device data stored in the first buffer and the plurality of sets of line data stored in the second buffer.

Description

Programmable logic controller, control system, data acquisition method and program

The present invention relates to a programmable logic controller, a control system, a data collection method, and a program.

A programmable logic controller is a controller that controls manufacturing equipment, transport equipment, inspection equipment, etc. in factory automation. In recent years, programmable logic controllers are connected to many external devices via networks and control the external devices by sending and receiving a lot of data.

In a programmable logic controller connected to many external devices, abnormalities such as unintended operations and errors may occur due to communication with the external devices. In order to identify the cause of an abnormality, a method is known in which communication data between a programmable logic controller and an external device is collected and confirmed.

For example, Patent Document 1 discloses a control device that can efficiently collect line data necessary to identify the cause of an abnormality by providing dynamically changeable filtering conditions when collecting line data. ing. Further, Patent Document 2 discloses a display device that can efficiently analyze line data by displaying line data and status logs of control devices and target devices in a chronologically correlated manner.

JP 2019-161388 Publication Japanese Patent Application Publication No. 2019-197461

When a programmable logic controller is connected to many external devices, a huge amount of line data is sent and received between the external devices. Therefore, when an abnormality occurs due to communication with an external device, it may be difficult to collect line data necessary to identify the cause of the abnormality. Further, even if it is possible to collect the line data necessary to identify the cause of the abnormality, it may take a lot of effort to analyze which line data has what kind of influence.

The present disclosure has been made in order to solve the above-mentioned problems, and provides a programmable logic controller, etc. that can facilitate the task of identifying the cause of abnormalities occurring in communication with external devices. The purpose is to provide.

In order to achieve the above object, a programmable logic controller according to the present disclosure includes a communication section, a program execution section, a device data collection section, a line data collection section, and a data output section. The communication unit communicates with external equipment. The program execution unit executes a user program for controlling a controlled object. The device data collection unit collects a plurality of device data stored in a plurality of devices that are storage areas referenced by the program execution unit, and stores each of the plurality of device data with time information when each device data was collected. It is associated and saved in the first buffer. The line data collection unit collects a plurality of line data that satisfies collection conditions from among the data communicated by the communication unit, associates the plurality of line data with time information at which each line data was communicated, and stores the line data in a second buffer. Save to. The data output unit outputs the plurality of device data stored in the first buffer and the plurality of line data stored in the second buffer.

In the present disclosure, a plurality of device data stored in a plurality of devices is collected, each of the collected plurality of device data is associated with time information when each device data was collected, and the data to be communicated with an external device is A plurality of pieces of line data that satisfy the collection conditions are collected, and the collected pieces of line data are associated with time information at which each piece of line data was communicated. Therefore, according to the present disclosure, it is possible to facilitate the task of identifying the cause of an abnormality occurring in communication with an external device.

A diagram showing the configuration of a control system according to Embodiment 1 A block diagram showing the hardware configuration of a PLC and an interface device according to Embodiment 1. Block diagram showing the functional configuration of the control system according to Embodiment 1 A diagram showing an example of device data collected by PLC in Embodiment 1 A diagram showing an example of line data collected by PLC in Embodiment 1 A diagram showing an example of a display screen displayed on the interface device in Embodiment 1. A diagram showing an example when device data or line data is selected on the display screen shown in FIG. A diagram showing an example when a device is selected on the display screen shown in FIG. 6 Flowchart showing the flow of data collection processing executed by the PLC according to the first embodiment Flowchart showing the flow of display output processing executed by the interface device according to Embodiment 1

Hereinafter, embodiments will be described in detail with reference to the drawings. In addition, the same or equivalent parts in the figures are given the same reference numerals.

(Embodiment 1)
FIG. 1 shows the configuration of a control system 1 according to the first embodiment. The control system 1 is an FA (factory automation) system installed in a factory, and corresponds to a production system that produces products. The control system 1 performs various processing, typified by processing, monitoring, and inspection, on the workpieces flowing on the production line.

As shown in FIG. 1, the control system 1 includes a PLC (programmable logic controller) 10, an interface device 20, and an external device 30.

The PLC 10 is a controller for controlling a controlled object in factory automation. Here, the objects to be controlled are manufacturing equipment, transport equipment, inspection equipment, etc. installed in a factory. The PLC 10 transmits various control commands to each of a plurality of control targets installed in a factory by executing a user program created in the interface device 20. Thereby, the PLC 10 comprehensively controls the manufacturing line in factory automation. PLC10 is an example of a control device.

The interface device 20 is a terminal device operated by a user. The interface device 20 is, for example, a general-purpose or industrial computer. The interface device 20 can create and edit a user program for controlling the PLC 10. The interface device 20 may also be called an engineering tool, a program creation support device, or the like. The interface device 20 is communicably connected to the PLC 10 via a USB (Universal Serial Bus) cable, LAN (Local Area Network), or other communication line.

The external device 30 is a device used in factory automation. External equipment 30 includes equipment to be controlled by PLC 10 in factory automation. Specifically, the external device 30 includes input devices such as sensors and cameras, and output devices such as actuators and arm robots. For example, the operation of the output device is controlled by the PLC 10 according to the detected value of the input device.

Note that the number of external devices 30 may be one or multiple. In addition to the devices to be controlled by the PLC 10, the external devices 30 may include devices that are not to be controlled by the PLC 10, such as databases, server devices, etc. External device 30 may be called a field device.

The external device 30 is communicably connected to the PLC 10 via a communication cable 31. The communication cable 31 is an industrial control network realized by communication lines installed within a factory. The communication cable 31 may be, for example, a USB cable or EtherNET (registered trademark), or may be EtherCAT (registered trademark) or EtherNet/IP (registered trademark) used as an industrial network protocol.

Next, the configurations of the PLC 10 and the interface device 20 will be explained. As shown in FIG. 2, the PLC 10 and the interface device 20 each include a processor 11, a main memory 12, an auxiliary memory 13, a clock section 14, an input section 15, an output section 16, a communication section 17, Equipped with. Each of these elements is connected via an internal bus.

The processor 11 includes a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a GPU (Graphics Processing Unit), and the like. The processor 11 implements various functions of the PLC 10 and the interface device 20 by executing programs stored in the auxiliary memory 13, and executes the processes described below.

The main memory 12 includes volatile storage devices such as DRAM (Dynamic Random Access Memory) and SRAM (Static Random Access Memory). A program is loaded into the main memory 12 from the auxiliary memory 13. Further, the main memory 12 is used as a work area for the processor 11.

The auxiliary memory 13 includes a nonvolatile storage device such as a ROM (Read Only Memory) and a flash memory. Auxiliary memory 13 stores various data used in processing by processor 11. The auxiliary memory 13 supplies data used by the processor 11 to the processor 11 according to instructions from the processor 11, and stores data supplied from the processor 11.

The clock section 14 includes elements typified by a crystal resonator and an oscillation circuit. The clock section 14 provides a clock signal to the processor 11 . Clock signals are utilized to measure time.

The input unit 15 includes input devices such as switches, input keys, and pointing devices. The input unit 15 acquires information input by the user and notifies the processor 11 of the acquired information.

The output unit 16 includes output devices such as an LED (Light Emitting Diode), an LCD (Liquid Crystal Display), and a speaker. The output unit 16 presents various information to the user according to instructions from the processor 11.

The communication unit 17 includes a communication interface circuit for communicating with external devices in accordance with well-known communication standards such as USB and Ethernet (registered trademark). The communication unit 17 receives a signal from the outside and outputs data indicated by this signal to the processor 11. Furthermore, the communication unit 17 transmits a signal indicating data output from the processor 11 to an external device. Specifically, the communication unit 17 of the PLC 10 communicates with the communication unit 17 of the interface device 20. Furthermore, the communication unit 17 of the PLC 10 communicates with the external device 30 via the communication cable 31.

Next, the functional configuration of the control system 1 will be described with reference to FIG. 3. As shown in FIG. 3, in the PLC 10, the processor 11 functionally includes a program acquisition section 110, a parameter setting section 120, a program execution section 130, a device data collection section 140, a line data collection section 150, It includes a data storage section 160 and a data output section 170. Further, in the interface device 20, the processor 11 functionally includes a program creation section 210, a display output section 220, and a selection section 230.

Each of these functions is realized by software, firmware, or a combination of software and firmware. Software and firmware are written as programs and stored in the auxiliary memory 13. The processor 11 implements each function by executing the program stored in the auxiliary memory 13.

In the interface device 20, the program creation unit 210 creates a user program 21 according to an operation received from the user via the input unit 15. The user program 21 is data that defines procedures for processing executed by the PLC 10.

The user program 21 is created using, for example, a graphical programming language or a high-level programming language. The graphical programming language is, for example, a motion program in a flowchart format such as a ladder language or SFC (sequential function chart). The high-level programming language is, for example, the C language. Hereinafter, as an example, the user program 21 will be described as a ladder program created in a ladder language.

A development tool for the user program 21 is installed on the interface device 20. The user operates the input unit 15 to combine a plurality of predefined types of commands on the development tool. Thereby, the user program 21 can be designed in accordance with the configuration of the external device 30.

After creating the user program 21, the program creation unit 210 transmits the created user program 21 to the PLC 10 via the communication unit 17 in response to an instruction from the user.

In the PLC 10, the program acquisition unit 110 acquires the user program 21 created in the interface device 20. When the user program 21 is transmitted from the interface device 20, the program acquisition unit 110 communicates with the interface device 20 via the communication unit 17, and receives the transmitted user program 21.

The parameter setting unit 120 sets various parameters related to the operation of the PLC 10. The parameters set by the parameter setting unit 120 include, for example, a device to be controlled, a file to be used, a timer setting value, a storage destination and storage format of device data and line data, and the like.

The parameter setting unit 120 sets such parameters based on information input by the user from the input unit 15 of the PLC 10. Alternatively, the parameter setting unit 120 may receive parameters from the interface device 20 and set the parameters.

The program execution unit 130 executes the user program 21 acquired by the program acquisition unit 110. Specifically, in order to control the controlled object, the program execution unit 130 generates a control command for the controlled object according to an arbitrarily created user program 21. Then, the program execution unit 130 transmits the generated control command to the controlled object via the communication cable 31. Thereby, the program execution unit 130 causes the controlled object to execute the operation according to the user program 21.

The device data collection unit 140 collects device data. Here, device data, also called device value, is data stored in a device. Here, the device is also called a device memory, and means a storage area on the main memory 12 provided for storing device data. Examples of the device include a relay device that holds 1 bit of information, a word device that holds 1 word of information, and the like. Device data includes, for example, an input state input from an input device such as a sensor or a camera among the external devices 30, an output state output from an output device such as an actuator or an arm robot among the external devices 30, and a user information. It shows the status of internal relays, timers, counters, data memory, etc. set on the program 21.

The program execution unit 130 uses the main memory 12 as a storage area for device data when executing the user program 21 to control the control target. Specifically, the program execution unit 130 controls the controlled object while temporarily storing data related to control according to the user program 21 in the main memory 12 as device data. Specifically, the data related to control is a measurement value measured by a sensor, a camera, etc., a control value transmitted from the PLC 10 to a controlled object, a state value indicating a control result by the controlled object, etc.

The device data collection unit 140 collects a plurality of device data stored in a plurality of devices, which are storage areas that the program execution unit 130 refers to when executing the user program 21 and controlling a control target. Then, the device data collection unit 140 stores the collected plurality of device data in a first buffer, which is a storage area on the main memory 12, in association with time information at which each device data was collected.

FIG. 4 shows an example of multiple device data stored in the first buffer. In FIG. 4, "time" represents the time when each device data was collected by the device data collection unit 140. “Target” represents identification information of a device that is a target of each device data. “Value” represents the value of each device data. The "value" is, for example, a measured value, a control value, a state value, etc. related to control according to the user program 21 as described above.

In this way, the device data collection unit 140 collects a plurality of pieces of device data used when the program execution unit 130 controls the control target according to the user program 21, in association with the time information at which each piece of device data was collected. . Device data linked to time information can be called "device log data." Note that the time information associated with each device data is not limited to the time itself, and may be, for example, the value of a scan counter as long as it is information indicating the time.

Returning to FIG. 3, the line data collection unit 150 collects a plurality of line data that satisfy the collection conditions from among the communication data communicated with the external device 30 by the communication unit 17. Here, the communication data is data such as packets and protocols transmitted between the PLC 10 and the external device 30 via the communication cable 31. The communication data includes data transmitted from the PLC 10 to the external device 30 and data transmitted from the external device 30 to the PLC 10.

For example, as communication data, data indicating a control command transmitted from the PLC 10 to a device to be controlled, data indicating a control result transmitted from the device to be controlled to the PLC 10, data indicating the state of the external device 30, a sensor, a camera. Various data exist, such as data measured by etc.

The collection conditions are filtering conditions set in advance to filter out unnecessary data from communication data. Specifically, the collection condition is satisfied when the data communicated by the communication unit 17 is data for operating the user program 21 or the device being used with preset parameters. Here, the preset parameters are parameters set by the parameter setting section 120.

Data operating a device means data written to or read from the device. In other words, data for operating the device used by the user program 21 corresponds to data written to or read from the device when the program execution unit 130 is executing the user program 21. Further, data for operating a device being used with preset parameters corresponds to data written to the device or data read from the device using parameters used when the PLC 10 performs various operations.

For example, a read command such as a monitor command does not satisfy the collection condition if it is not used in the user program 21 or parameters. Therefore, line data collection unit 150 does not collect communication data if the communication data corresponds to a read command. Furthermore, communication data that is relayed to another device, that is, communication data where neither the destination nor the source is the PLC 10, does not satisfy the collection condition. Therefore, the line data collection unit 150 does not collect communication data to be relayed to other devices.

In this way, when data transmitted and received by the communication unit 17 between the PLC 10 and the external device 30 is written to or read from a device used in the user program 21 or parameters, the data is Collect as data.

When the communication unit 17 communicates with the external device 30, the line data collection unit 150 accesses the communication unit 17 and determines whether the communication data satisfies the collection conditions set in this way. do. As a result of the determination, the line data collection unit 150 does not collect communication data that does not satisfy the collection conditions, but collects data that satisfies the collection conditions as line data.

The line data collection unit 150 stores the collected line data in a second buffer, which is a storage area on the main memory 12, in association with time information at which the line data was communicated. Note that the second buffer is a storage area different from the first buffer in which device data on the main memory 12 is stored.

FIG. 5 shows an example of multiple line data stored in the second buffer. In FIG. 5, "time" represents the time when each line data was transmitted and received. "Src" represents the device that is the transmission source of each line data. “Dst” represents the device to which each line data is transmitted.

In this way, the line data collection unit 150 links the line data communicated with the external device 30 when the program execution unit 130 controls the controlled object according to the user program 21 to the time information communicated. collect. Line data linked to time information can be called "line log data." Note that the time information associated with each line data is not limited to the time itself, and may be, for example, the value of a scan counter as long as it is information indicating the time.

In this way, the line data collection unit 150 collects line data for operating the device used by the user program 21 or parameters from among the data communicated by the communication unit 17. As a result, when an abnormality occurs due to communication between the PLC 10 and the external device 30, line data necessary to identify the cause of the abnormality can be efficiently collected from a huge amount of line data. I can do it. Furthermore, since it is not necessary to completely understand the device being used in the user program 21 or parameters, even a user with little knowledge can easily collect only the line data for operating the device being used. can.

Further, as described above, the collection condition is satisfied when the communication data is data for operating a device used by the user program 21 or parameters. Therefore, even if the user program 21 or parameters are changed, the line data collection unit 150 can collect appropriate line data.

For example, when the user changes the user program 21 on the interface device 20, or when some parameter is changed by the parameter setting unit 120, the device used in the user program 21 or the parameter changes in accordance with the change. be done. Therefore, the devices subject to the collection conditions are automatically changed to follow the change. As a result, the line data collection unit 150 collects line data corresponding to the changed user program 21 or parameters without requiring the user to take the trouble of resetting the collection conditions every time the user program 21 or parameters are changed. be able to.

Returning to FIG. 3, when a predetermined storage condition is satisfied, the data storage unit 160 saves the plurality of device data stored in the first buffer and the plurality of line data stored in the second buffer. It is saved in the auxiliary memory 13 of the PLC 10.

Here, the storage condition is a condition that determines the timing for moving multiple device data and multiple line data from the main memory 12 to the auxiliary memory 13. For example, the storage condition may be such that when at least one of the size of the plurality of device data stored in the first buffer and the size of the plurality of line data stored in the second buffer exceeds a predetermined threshold, It is filled. Alternatively, the storage condition may be satisfied when a predetermined periodic timing arrives.

More specifically, the data storage unit 160 stores a plurality of device data and a plurality of line data in a storage destination set by the user in a storage format set by the user. Specifically, by operating the input unit 15 of the PLC 10 or the interface device 20, the user can specify a desired data folder in the auxiliary memory 13 as the storage destination. Furthermore, by operating the input unit 15 of the PLC 10 or the interface device 20, the user can specify a desired data file format as the storage format. The parameter setting unit 120 sets the storage destination and storage format according to such user specifications.

In this way, the user can freely specify the storage destination and storage format. Therefore, a plurality of device data and a plurality of line data associated with time information can be stored for easy use by the user.

The data output unit 170 outputs the plurality of device data and the plurality of line data stored by the data storage unit 160 to the interface device 20. Specifically, when a predetermined output timing arrives or in response to a request from the interface device 20, the data output unit 170 outputs the plurality of device data and the plurality of line data stored by the data storage unit 160. is transmitted to the interface device 20 via the communication unit 17.

In the interface device 20, the display output unit 220 acquires multiple device data and multiple line data output from the PLC 10, and displays the acquired multiple device data and multiple line data. Specifically, upon acquiring a plurality of device data and a plurality of line data from the PLC 10, the display output section 220 displays the display screen 40 shown in FIG. 6 on the LCD in the output section 16.

More specifically, the display output unit 220 displays a display screen 40 that includes a program monitor 41, a line data list 42, a device data list 43, and a device monitor 44. Here, the program monitor 41 displays the contents of the user program 21. The line data list 42 displays a list of a plurality of line data collected by the PLC 10. The device data list 43 displays a list of a plurality of device data collected by the PLC 10. The device monitor 44 displays current values of multiple devices. In this way, the display output section 220 displays the plurality of line data and the plurality of device data stored by the data storage section 160 in a list format.

When such a display screen 40 is displayed, the user can select any one of the plurality of line data displayed in the line data list 42 and the plurality of device data displayed in the device data list 43. Data or device data can be selected. For example, the user operates the input unit 15 of the interface device 20 to click desired line data or device data from the line data list 42 and the device data list 43. In accordance with such user operations, the selection unit 230 selects one of the plurality of device data displayed by the display output unit 220 or one of the plurality of line data displayed by the display output unit 220. Select one of the line data.

Specifically, when device data is selected by the selection unit 230, the display output unit 220 displays the time associated with the selected device data among the plurality of line data displayed in the line data list 42. Highlight the line data associated with the closest time information. On the other hand, when line data is selected by the selection unit 230, the display output unit 220 selects the most suitable time information associated with the selected line data among the plurality of device data displayed in the device data list 43. Highlight device data with associated time information.

As a specific example, FIG. 7 shows an example where one device data or one line data is selected. When the device data surrounded by a broken line in the device data list 43 is selected, the display output unit 220 displays the time of the selected device data among the plurality of line data displayed in the line data list 42. The line data surrounded by a broken line is highlighted as the line data with the closest time to "2021/11/10 9:00:16:100". On the contrary, when the line data surrounded by a broken line is selected from the line data list 42, the display output unit 220 displays the selected line data from among the plurality of device data displayed in the device data list 43. The device data surrounded by a broken line is highlighted as the device data with the closest time to "2021/11/10 9:00:16:100" which is the time of the line data.

In addition, for highlighting, the data should be displayed in a manner that allows it to be distinguished from other data, such as displaying the data in a different color or size from other data, or displaying the data in a blinking manner. means.

In this way, when one of the line data and device data is selected, by highlighting the data with the closest time between the other line data and device data, the line data and device data can be combined. You can visually understand the relationship. Therefore, it helps in analyzing the causes of abnormality. In addition, even if you do not understand the packet structure of line data, you can understand the relationship between line data and device data with intuitive operations, so even users with little knowledge can efficiently perform analysis work. can.

Furthermore, the user can select any one device from among the multiple devices displayed on the device monitor 44. For example, the user operates the input unit 15 of the interface device 20 to click on a desired device from the device monitor 44. The selection unit 230 selects one of the plurality of devices displayed by the display output unit 220 in accordance with such user operations. Note that when selecting a device, the user is not limited to selecting a device from among the plurality of devices displayed on the device monitor 44, and may select a device used in the user program 21.

When any device is selected by the selection unit 230, the display output unit 220 selects one of the plurality of device data displayed in the device data list 43 and the plurality of line data displayed in the line data list 42. Highlights all device data and line data that operated the device.

As a specific example, FIG. 8 shows an example where one device from the device monitors 44 is selected. When the device “D6” surrounded by a broken line in the device monitor 44 is selected, the display output unit 220 displays all the device data whose target is “D6” among the plurality of device data displayed in the device data list 43. Highlight device data. Specifically, the display output unit 220 highlights a plurality of device data surrounded by broken lines in FIG. 8 .

At this time, the display output unit 220 also highlights the line data that is closest to the time information associated with each device data whose target is "D6" among the plurality of line data displayed in the line data list 42. do. Specifically, the display output unit 220 highlights the plurality of line data surrounded by broken lines in FIG. 8 .

In this way, when a specific device is selected, by highlighting all the device data and line data that operated that device, it is possible to visually understand the change in the value of the device in association with the line data. Therefore, it helps in analyzing the causes of abnormalities.

Next, the flow of the data collection process executed in the PLC 10 will be described with reference to the flowchart shown in FIG.

The data collection process shown in FIG. 9 is an example of a data collection method executed by the PLC 10. The data collection process starts when the PLC 10 receives an instruction to execute the user program 21. The user program 21 is created in advance by the program creation section 210 in the interface device 20, and is acquired by the program acquisition section 110 in the PLC 10.

When the data collection process is started, the processor 11 of the PLC 10 functions as the program execution unit 130 and executes the user program 21 (step S11).

When the user program 21 is executed, the processor 11 functions as the device data collection unit 140 and collects device data stored in the device referenced when the user program 21 is executed (step S12). Then, the processor 11 stores the collected device data in the first buffer in association with the time information at which the device data was collected (step S13).

After collecting the device data, the processor 11 determines whether or not it has communicated with the external device 30 via the communication unit 17 (step S14). When communicating with the external device 30 (step S14; YES), the processor 11 next determines whether the communication data satisfies the collection conditions (step S15).

If it is determined that the communication data satisfies the collection conditions (step S14; YES), the processor 11 functions as the line data collection unit 150 and collects the communication data as line data (step S16). Then, the processor 11 stores the collected line data in the second buffer in association with the time information at which the line data was communicated (step S17).

On the other hand, if the processor 11 is not communicating with the external device 30 (step S14; NO), or if the communication data does not satisfy the collection conditions even if it is communicating with the external device 30 (step S15; NO), the processor 11 skips steps S16 and S17.

After that, the processor 11 determines whether a predetermined storage condition is satisfied (step S18). If the storage condition is satisfied (step S18; YES), the processor 11 functions as the data storage section 160 and stores the device data and line data in the auxiliary memory 13 (step S19). On the other hand, if the storage condition is not satisfied (step S18; NO), the processor 11 skips step S19.

After that, the processor 11 returns the process to step S11. Then, the processor 11 repeats the processes of steps S11 to S19 until the execution of the user program 21 is finished, and collects device data and line data during the process. With the above, the collection process shown in FIG. 9 ends.

Next, the flow of display output processing executed in the interface device 20 will be described with reference to the flowchart shown in FIG.

The display output process shown in FIG. 10 is an example of a display output method executed by the interface device 20. The display output process is executed by the display output unit 220 when the interface device 20 receives a command to display device data and line data.

When the display output process is started, the display output unit 220 acquires the device data and line data collected and stored in the PLC 10 (step S21).

After acquiring the device data and line data, the display output unit 220 displays the acquired device data and line data (step S22). For example, the display output unit 220 displays a display screen 40 including a program monitor 41, a line data list 42, a device data list 43, and a device monitor 44, as shown in FIG.

Next, the display output unit 220 determines whether any device data has been selected by the user from the displayed device data list 43 (step S23). If device data is selected (step S23; YES), the display output unit 220 highlights the line data whose time is closest to the time of the selected device data, as shown in FIG. 7 (step S24). .

On the other hand, if device data is not selected (step S23; NO), the display output unit 220 skips step S24.

Next, the display output unit 220 determines whether any line data from the displayed line data list 42 has been selected by the user (step S25). If line data is selected (step S25; YES), the display output unit 220 highlights the device data whose time is closest to the time of the selected line data (step S26), as shown in FIG. .

On the other hand, if line data is not selected (step S25; NO), the display output unit 220 skips step S26.

Next, the display output unit 220 determines whether any device has been selected by the user on the device monitor 44 (step S27). If a device is selected (step S27; YES), the display output unit 220 highlights the device data and line data corresponding to the selected device, as shown in FIG. 8 (step S28).

On the other hand, if no device is selected (step S27; NO), the display output unit 220 skips step S28.

After that, the display output unit 220 returns the process to step S23. Then, the display output unit 220 repeats the processing of steps S23 to S28 while the display screen 40 is displayed. This allows the user to recognize the relationship between device data and line data when the user program 21 is executed.

As described above, the PLC 10 according to the first embodiment collects a plurality of device data stored in a plurality of devices that are storage areas referenced by the program execution unit 130, and each of the collected device data is associated with the time information at which each device data was collected, a plurality of line data that satisfy the collection conditions are collected from among the data communicated by the communication unit 17, and each line data is Correlate with the communicated time information.

In this way, out of the data communicated by the communication unit 17, data that satisfies the collection conditions is collected as line data, so it is possible to identify the cause of an abnormality from a huge amount of communication data without running out of memory. It is possible to collect the necessary line data. Since device data and line data are associated with time information, if an abnormality such as an unintended operation or error occurs due to communication with an external device 30, it is possible to identify which external device the communication caused. Easier to identify. As a result, communication between the PLC 10 and the external device 30 can be efficiently collected and analyzed, making it easier to identify the cause of abnormalities occurring in the communication between the PLC 10 and the external device 30. can.

(Embodiment 2)
Next, a second embodiment will be described. Descriptions of configurations and functions similar to those in Embodiment 1 will be omitted as appropriate.

In the first embodiment described above, the collection conditions for the line data collection unit 150 to collect line data are such that the data communicated by the communication unit 17 is transmitted by the user program 21 or the device being used with preset parameters. If the data to be manipulated is met. On the other hand, in the second embodiment, the collection condition is satisfied when the data communicated by the communication unit 17 is data related to the function used by the user program 21 or preset parameters. It will be done. Note that the collection conditions in Embodiments 1 and 2 can be referred to as "first collection conditions" and "second collection conditions," respectively.

In the collection conditions in the second embodiment, data related to a function used by the user program 21 or preset parameters means data required to realize the function. For example, when a time synchronization function is used in the user program 21 or a parameter, an example of data related to the function is SNTP (Simple Network Time Protocol). Therefore, in this case, SNTP satisfies the collection condition. Alternatively, when a network drive function is used in the user program 21 or a parameter, an example of data related to the function is SMB (Server Message Block). Therefore, in this case, SMB satisfies the collection condition.

When the communication unit 17 communicates with the external device 30, the line data collection unit 150 accesses the communication unit 17 and determines whether the communication data satisfies the collection conditions set in this way. do. As a result of the determination, the line data collection unit 150 does not collect communication data that does not satisfy the collection conditions, but collects data that satisfies the collection conditions as line data. The line data collection unit 150 stores the collected line data in a second buffer, which is a storage area on the main memory 12, in association with time information at which the line data was communicated. The other configurations and functions are the same as in the first embodiment.

In this way, in the second embodiment, the line data collection unit 150 collects line data related to the functions used in the user program 21 or parameters from among the data communicated by the communication unit 17. As a result, when an abnormality occurs due to communication between the PLC 10 and the external device 30, line data necessary to identify the cause of the abnormality can be efficiently collected from a huge amount of line data. I can do it. Further, since there is no need to be aware of the protocols used by each function, even a user with little knowledge can easily collect only the line data of the protocols related to each function.

Further, as described above, the collection condition is satisfied when the communication data is data related to a function used in the user program 21 or parameters. Therefore, even if the user program 21 or parameters are changed, the line data collection unit 150 can collect appropriate line data.

For example, when the user changes the user program 21 on the interface device 20, or when some parameter is changed by the parameter setting unit 120, the functions used in the user program 21 or the parameters are changed in accordance with the change. be done. Therefore, the functions subject to the collection conditions are automatically changed in accordance with the change. As a result, the line data collection unit 150 collects line data corresponding to the changed user program 21 or parameters without requiring the user to take the trouble of resetting the collection conditions every time the user program 21 or parameters are changed. be able to.

Note that the user can, for example, manually set which of the collection conditions described in Embodiment 1 and the collection conditions described in Embodiment 2 is to be used. Alternatively, the collection conditions described in Embodiment 1 and the collection conditions described in Embodiment 2 may be combined using a logical OR or AND and used as conditions for the line data collection unit 150 to collect line data. good.

(Modified example)
Although the embodiments have been described above, it is possible to combine each embodiment, or to modify or omit each embodiment as appropriate.

In the above embodiment, the PLC 10 and the processor 11 of the interface device 20 functioned as each unit shown in FIG. 3 by executing the program. However, processor 11 may also be dedicated hardware. The dedicated hardware is, for example, a single circuit, a composite circuit, a programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. When the processor 11 is dedicated hardware, the functions of each part may be realized by separate hardware, or the functions of each part may be realized by a single piece of hardware.

Additionally, some of the functions of each part may be realized by dedicated hardware, and the other part may be realized by software or firmware. In this way, the processor 11 can implement the above-mentioned functions using hardware, software, firmware, or a combination thereof.

By applying an operation program that defines the operation of the PLC 10 or the interface device 20 to an existing computer such as a personal computer or an information terminal device, it is also possible to cause the computer to function as the PLC 10 or the interface device 20.

In addition, the distribution method of such programs is arbitrary; for example, it can be distributed on computer-readable recording media such as CD-ROM (Compact Disk ROM), DVD (Digital Versatile Disk), MO (Magneto Optical Disk), memory card, etc. It may be stored and distributed, or it may be distributed via a communication network such as the Internet.

The present disclosure is capable of various embodiments and modifications without departing from the broad spirit and scope of the present disclosure. Moreover, the embodiments described above are for explaining this disclosure, and do not limit the scope of this disclosure. That is, the scope of the present disclosure is indicated by the claims rather than the embodiments. Various modifications made within the scope of the claims and the meaning of the disclosure equivalent thereto are considered to be within the scope of this disclosure.

1 Control system, 10 PLC, 11 Processor, 12 Main memory, 13 Auxiliary memory, 14 Clock unit, 15 Input unit, 16 Output unit, 17 Communication unit, 20 Interface device, 21 User program, 30 External equipment, 31 Communication cable, 40 Display screen, 41 Program monitor, 42 Line data list, 43 Device data list, 44 Device monitor, 110 Program acquisition unit, 120 Parameter setting unit, 130 Program execution unit, 140 Device data collection unit, 150 Line data collection unit, 160 Data storage section, 170 data output section, 210 program creation section, 220 display output section, 230 selection section

Claims

a communication section that communicates with external equipment;
a program execution unit that executes a user program for controlling a controlled object;
Collecting a plurality of device data stored in a plurality of devices that are storage areas referenced by the program execution unit, and associating each of the plurality of device data with time information at which each device data was collected. a device data collection unit that stores the data in a buffer;
A line that collects a plurality of line data that satisfies a collection condition from among the data communicated by the communication unit, and stores the plurality of line data in a second buffer in association with time information at which each line data was communicated. a data collection department;
a data output unit that outputs the plurality of device data stored in the first buffer and the plurality of line data stored in the second buffer;
Programmable logic controller.
The collection condition is satisfied when the data communicated by the communication unit is data for operating the device being used with the user program or preset parameters;
The programmable logic controller according to claim 1.
The collection condition is satisfied when the data communicated by the communication unit is data related to a function used in the user program or a preset parameter.
The programmable logic controller according to claim 1 or 2.
If a predetermined storage condition is met, the plurality of device data stored in the first buffer and the plurality of line data stored in the second buffer are stored in a storage destination set by the user. , further comprising a data storage unit that stores the data in a storage format set by the user.
A programmable logic controller according to any one of claims 1 to 3.
A control system comprising the programmable logic controller according to any one of claims 1 to 4 and an interface device,
In the programmable logic controller,
The data output unit outputs the plurality of device data and the plurality of line data to the interface device,
The interface device includes:
a display output unit that displays the plurality of device data and the plurality of line data output by the data output unit;
control system.
Any device data among the plurality of device data displayed by the display output section or line data among the plurality of line data displayed by the display output section according to a user's operation. further comprising a selection section for selecting the
The display output section is
When the device data is selected by the selection unit, highlight line data associated with time information closest to time information associated with the selected device data among the plurality of line data;
when the line data is selected by the selection unit, highlighting device data associated with time information closest to time information associated with the selected line data, among the plurality of device data;
A control system according to claim 5.
The display output unit further displays the plurality of devices, and when any one of the plurality of devices is selected by a user operation, the display output unit displays the plurality of device data and the plurality of line data. , highlighting all device data and line data that operated the selected device;
The control system according to claim 5 or 6.
Execute the user program to control the controlled object,
Collecting a plurality of device data stored in a plurality of devices that are storage areas referenced when executing the user program,
associating each of the plurality of collected device data with time information at which each device data was collected;
Among the data communicated with external devices, collect multiple line data that meets the collection conditions,
associating the plurality of collected line data with time information at which each line data was communicated;
Data collection methods.
A computer equipped with a communication unit that communicates with external equipment,
a program execution unit that executes a user program for controlling a controlled object;
Collecting a plurality of device data stored in a plurality of devices that are storage areas referenced by the program execution unit, and associating each of the plurality of device data with time information at which each device data was collected. a device data collection unit that stores it in a buffer;
A line that collects a plurality of line data that satisfies a collection condition from among the data communicated by the communication unit, and stores the plurality of line data in a second buffer in association with time information at which each line data was communicated. data collection department,
functioning as a data output unit that outputs the plurality of device data stored in the first buffer and the plurality of line data stored in the second buffer;
program.