JP2011118733A - Programmable logic controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To implement a programmable logic controller (PLC) which is capable of confirming operation states of all modules including a CPU module per station or unit on the host PC side to acquire information effective for cause analysis of an alarm. <P>SOLUTION: The PLC comprising the host PC and the station communicating with the PC and including the plurality of modules including the CPU module is provided with a station monitor in the host PC, which acquires operation state codes of the plurality of modules via the CPU module of the station and, in the case of the occurrence of an alarm, displays an alarm message acquired by referring to an alarm message file corresponding to the operation state codes. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a programmable logic controller (hereinafter referred to as “PLC”) including a rank PC and a station having a plurality of modules including a CPU module that communicate with the PC. Regarding the PLC, there is a technical disclosure in Patent Document 1.

FIG. 9 is a functional block diagram showing a conventional configuration of the PLC. The PLC includes a host PC 10 and a station 20 that communicates with the PC and includes a plurality of modules including a CPU module. The station 20 includes a plurality of units 30, 40, 50 in which a predetermined number of modules are accommodated. The CPU module 31 of the unit 30 can monitor the operating state by ladder program editing software on the host PC 10 side.

  FIG. 10 is a schematic diagram showing an editing mode of the ladder program installed in the CPU module by the host PC 10. In order to confirm the operating state of the CPU module 31, the actual machine and the host PC 10 are connected with a cable and confirmed from the status bar of the ladder program editing software. The CPU module is the only module whose operating status is always displayed by the ladder program editing software.

The operational status of various modules in the unit is indicated by LEDs. For example, in the standby state, the character string “RDY” is lit. In the case of modules other than the CPU module, the operation state is confirmed by the following method.
(1) Go to the control panel at the site where the station 20 is installed and visually check it.
(2) Access individual modules from the host PC 10 side and open and confirm a screen for referring to the operating state.

JP 2006-202165 A

The conventional PLC configuration has the following problems.
(1) The operating states of all modules constituting the unit, including the CPU module, cannot be collectively confirmed on the host PC.

(2) In order to confirm the operating state by looking at the LED display of modules other than the CPU module, it is necessary to go to a place where the actual machine is located. For this reason, when the actual machine is installed in a remote place, it takes time to confirm and an emergency response cannot be made.

(3) Although the station is installed on the control panel, if you do not want to open it for dustproofing and waterproofing, or if it is installed in a place where workers are difficult to enter, open the control panel and check the module operation. It is not easy to do.

(4) In the method of accessing each module, the access procedure and the display format are different for each module, and there are cases where information effective for alarm analysis cannot be obtained. In a system with a very large number of modules, the confirmation work becomes extremely complicated.

(5) Since each module including the CPU module displays only LEDs for operation / standby / error occurrence, etc. regarding its operating state, it is effective for alarm analysis even though it can be confirmed that an alarm or error has occurred. There are cases where it is difficult to analyze the cause of an alarm occurrence without message support.

(6) The conventional monitoring function of the CPU module by the ladder program editing software is mainly for confirming the operation of the CPU module, and therefore does not have a function for confirming the operation of the module in units or stations.

  An object of the present invention is to realize a PLC capable of confirming operating states of all modules including a CPU module in units of stations and units on the host PC side and acquiring information effective for alarm cause analysis. It is in.

In order to achieve such a subject, the present invention has the following configuration.
(1) In a PLC composed of a host PC and a station having a plurality of modules including a CPU module that communicate with the PC.
The upper level is obtained by acquiring an operation status code of the plurality of modules via the CPU module of the station, and displaying an alarm message acquired by referring to an alarm message file corresponding to the operation status code when an alarm is generated. A PLC comprising a station monitor provided in a PC.

(2) The PLC according to (1), wherein the station monitor includes a display screen for displaying an image of a module stored in each unit storing a predetermined number of the modules.

(3) The PLC according to (1) or (2), wherein the station monitor includes a display screen for displaying details of an operating state for each displayed module.

(4) The station monitor includes a display screen for displaying an alarm message from an alarm occurrence icon on a module display screen, the operation state of which is displayed in detail, according to any one of (1) to (3) PLC.

According to the present invention, the following effects can be expected.
(1) Since the operating status of the various modules that make up the unit can be confirmed in a batch on the host PC side, the operating status can be monitored on the PC screen without going directly to the actual machine. Is possible.

(2) By displaying the alarm message screen from the warning icon of the module displayed on the screen, it is possible to support early identification of the cause of the alarm / error.

It is a functional block diagram which shows one Example of PLC to which this invention is applied. It is explanatory drawing of the operation status code | cord | chord of a module acquired by the station side. It is an example of the image display screen of the unit in a station. It is an example of a detailed display screen of a module operating state. It is an alarm message display screen. It is a flowchart which shows the acquisition procedure of an operation state code. It is a flowchart which shows an alarm message display procedure. It is a flowchart which shows the response procedure by the station side. It is a functional block diagram which shows the conventional structure of PLC. It is a schematic diagram which shows the edit form of the ladder program by which CPU module was mounted by high-order PC.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a functional block diagram showing an embodiment of a PLC to which the present invention is applied. The same elements as those of the conventional configuration described with reference to FIG.

  The characteristic part of the present invention shown in FIG. 1 has a configuration including a station monitor 100 provided in the host PC 10, a station 200 for collecting operation status codes of a plurality of modules, and an alarm message file 300 provided in the host PC 10.

  The station monitor 100 includes a display unit 101, a control unit 102, a communication unit 103 that communicates with the station 200, an input unit 104 that is an interface with the user U, and a storage unit 105 for the acquired alarm message.

  The station 200 includes a CPU module 201, another module 202 that communicates with the CPU module, and a communication unit 203 that communicates with the communication unit 105 of the station monitor 100.

  FIG. 2 is an explanatory diagram of module operation status codes acquired on the station 200 side. The operating state code of each module including the CPU module is composed of an address and a numerical value.

  In response to an operation status code acquisition request transmitted from the station monitor 100 via the communication unit 203, the CPU module 201 communicates the operation status code of the CPU module 201 itself and the operation status code of each module acquired from another module. A response is transmitted to the station monitor 100 via the unit 203.

  An example of the monitor screen of the display unit 101 will be described with reference to FIGS. FIG. 3 is an example of an image display screen of a unit in the station 200. By selecting a station in the station selection dialog 401 from the monitor screen 400 and selecting a unit displayed hierarchically below the station in the tree view 402, the face plate of the module accommodated in the unit is displayed in the unit image 403. Is displayed.

  FIG. 4 is an example of a detailed display screen of the operating state of the module. By selecting a module name in the tree view 402, details of the operating state of the module are displayed in the module view 404. The module operating status display is updated at regular intervals.

  FIG. 5 is an alarm message display screen. When the alarm / error LED is lit on the detailed display screen by the module view 404 shown in FIG. 4, a warning icon 405 is displayed. A context menu is displayed by holding the mouse over the warning icon 405 [message display]. ], A message effective for the cause analysis of the alarm is displayed in the message window 406.

  FIG. 6 is a flowchart showing a procedure for the station monitor 100 to obtain an operation status code from the station 200. When the process is started in step S1, the control unit 102 requests the communication unit 103 to acquire an operation state code in step S2.

  In step S <b> 3, the communication unit 103 transmits an operation state code acquisition request to the station 200. In step S <b> 4, the station 200 transmits the operation status code of the module to the communication unit 103.

  In step S5, the communication unit 103 determines an LED display state corresponding to the acquired operation state code. If the alarm / error LED display is ON in the branch process of step S6, the communication unit 103 transmits an alarm message acquisition request to the alarm message table 300 in step S7.

  In step S <b> 8, the alarm message table 300 transmits to the communication unit 103 an alarm message that has been edited and held in advance corresponding to the operating state code. In step S <b> 9, the communication unit 103 transmits the acquired alarm message to the control unit 102. In step S10, the control unit 102 transmits an alarm message to the storage unit 105, and in step S11, the storage unit 105 stores the alarm message.

  In step S <b> 12, the communication unit 103 transmits the LED display state to the control unit 102. In step S13, the control unit 102 transmits the LED display state to the display unit 101. In step S14, the display unit 101 updates the screen display. In step S15, the processing routine ends. If the alarm / error LED display is not ON in the branch process of step S6, the process skips to step S12.

The flow of this process is summarized as follows.
(1) The communication unit 103 acquires the operation status code of the target module from the station 200.
(2) The acquired operating state code is compared with the alarm message table 300, and an alarm message corresponding to the operating state code is generated.
(3) The generated alarm message is stored in the storage unit 105.

  FIG. 7 is a flowchart showing an alarm message display procedure. When the process is started in step S1, the user U uses the input unit 104 to right-click the detailed display warning icon 405 in FIG. 4 in step S2. By right-clicking, a context menu is displayed on the display unit 101.

  In step S3, the user clicks [Display Message] from the displayed context menu. Based on this click, the input unit 104 transmits an alarm acquisition request to the control unit 102 in step S4.

  In step S <b> 5, the control unit 102 transmits an alarm message acquisition request to the storage unit 105. In step S <b> 6, the storage unit 105 transmits an alarm message to the control unit 102. In step S7, the control unit 102 transmits an alarm message display request to the display unit 101. In step S8, the display unit 101 displays an alarm message and ends the process in step S9.

  FIG. 8 is a flowchart showing a response procedure on the station 200 side. When the process starts in step S1, the station 200 waits for an operation state code acquisition request from the communication unit 103 in step S2.

  When the operating state code is acquired in the branching process in step S3, the CPU module transmits an operating state code acquisition request to each connected module in step S4, and in step S5, each module sends it to the CPU module. Sends its own operating status code.

  In step S6, the CPU module transmits the operation status code of each module acquired together with its own operation status code to the communication unit 103, and ends the process in step S7. If there is no operation state code acquisition request from the communication unit 103 at the branch of step S3, the process skips to step S7 and ends.

  In the present invention, the monitor screen is switched from the tree view 402 shown in FIG. When a unit name in the tree view is double-clicked, a unit image 403 is displayed. When a module name in the unit is double-clicked, a module view 404 is displayed in the detailed display of FIG.

  When a warning icon 405 is displayed in the module view 404 of the monitor screen, a context menu is displayed by hovering the mouse over the warning icon and selecting [Display Message] displays an alarm on the alarm message display screen of FIG. An error message window 406 is displayed.

  The alarm message displayed in the message window 406 can be closed by clicking the [Close] button at the upper right of the message window 406.

  As described above, the operation state of the module can be intuitively confirmed on the PC by the application of the present invention in units of stations or units. Further, when the operating status of the module is an alarm / error, an alarm message can be confirmed from the warning icon next to the operating status button.

  In a PLC with a conventional configuration, the user checks the operating status of the module, and in the case of an alarm / error status, the task of analyzing the program, checking the parameters in the module, examining the instruction manual, etc. is performed to identify the cause. Although it was necessary, this alarm message display can reduce the trouble of identifying the cause.

10 Host PC
100 station monitor 101 display unit 102 control unit 103 communication unit 104 input unit 105 storage unit 200 station 201 CPU module 202 other module 203 communication unit 300 alarm message file

Claims (4)

In a programmable logic controller composed of a host PC and a station having a plurality of modules including a CPU module that communicate with the PC,
The upper level is obtained by acquiring an operation status code of the plurality of modules via the CPU module of the station, and displaying an alarm message acquired by referring to an alarm message file corresponding to the operation status code when an alarm is generated. A programmable logic controller comprising a station monitor provided in a PC.   The programmable logic controller according to claim 1, wherein the station monitor includes a display screen that displays an image of a module stored in each unit that stores a predetermined number of the modules.   The programmable logic controller according to claim 1, wherein the station monitor includes a display screen that displays details of an operating state for each displayed module.   4. The programmable logic controller according to claim 1, wherein the station monitor includes a display screen in which an operation state is displayed in detail and an alarm message is displayed from an alarm occurrence icon on the module display screen. 5.