JP2007213341A - Programmable logic controller, information processing apparatus, control program, and table preparation program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain a processing depending on urgency for every generated error. <P>SOLUTION: A program or data prepared by a PC is stored in a storage device incorporated in a PLC and is used for the execution of sequence control. In addition to a control operation program for executing main control, data such as an error processing program and an error information table are stored in the PLC. An error level indicating the priority of error reset in each error code, a message to be displayed at the occurrence of an error, and so on, are defined in the error information table. When an error is generated in a sequence control system, the PLC specifies an error level corresponding to the sort of the generated error on the basis of the error information table. Then the PLC rearranges information concerned with the generated error, such as a message allocated to the error code, on the basis of the specified error level and displays the rearranged information on a display device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a programmable logic controller, an information processing device, a control program, and a table creation program. For example, the present invention relates to error processing control in sequence control.

2. Description of the Related Art Programmable logic controllers (hereinafter referred to as PLCs) are used in a wide range of fields as FA (factory automation) control devices that control production facilities and the like.
The PLC is a device that takes in an input signal from an input device such as a sensor or a mechanical switch, and freely controls an output device such as a solenoid valve or a motor based on preprogrammed conditions.
In such a PLC operation, for example, a method for dealing with a problem (error) such as an arithmetic processing error during program execution has been proposed in the following patent document.
JP 2003-330501 A

  In Patent Document 1, when an error occurs in the arithmetic processing unit, the object is controlled based on the abnormal output data that controls the on / off state of the object to be controlled, which is stored in advance in the memory. Techniques to perform have been proposed.

The PLC described in Patent Document 1 is configured such that error handling processing is executed in the order in which errors occurred.
Therefore, in the PLC described in Patent Document 1, when a plurality of errors occur at the same time (short time), even important errors are processed in the order in which the errors occurred.

Further, not only when actual system control is performed in a production line or the like, but also in the stage of system development such as a test process, for example, processing for handling an error that has occurred is executed. In the development stage of such a system, many errors (bugs) exist in the program, and thus many errors may occur.
However, even if an important error exists among a large number of errors, the errors are processed in the order in which the errors occurred, as in the technique described in Patent Document 1.

Accordingly, a first object of the present invention is to enable processing according to the degree of urgency (importance) for each error that has occurred.
In addition, a second object of the present invention is to generate a reference table used when specifying the urgency (importance) for each error that has occurred.

The invention according to claim 1 is a programmable logic controller that performs sequence control by sequentially executing a program indicating control contents based on a signal input from a connected device, and specifies the type of error. A reference table acquisition unit that acquires a reference table in which an error type and an error level indicating an error cancellation priority are associated; an error information acquisition unit that acquires information on an error that has occurred during execution of the sequence control; , Based on the error information acquired by the error information acquisition means, a type specifying means for specifying an error type corresponding to the error that has occurred, and storing the error information acquired by the error information acquisition means in a storage device And an error level corresponding to the error type specified by the type specifying means The first object comprises: level specifying means for specifying based on the reference table; and display means for displaying information on the error that has occurred in association with the error level specified by the level specifying means. To achieve.
According to a second aspect of the present invention, in the programmable logic controller according to the first aspect, the error information stored in the storage device is rearranged in descending order of priority based on the error level specified by the level specifying means. Sorting means is provided, and the display means displays information on errors that have occurred based on the order sorted by the sorting means.
According to a third aspect of the present invention, in the programmable logic controller according to the first or second aspect, the reference table obtaining unit obtains a reference table in which an error type, an error level, and an error message are associated with each other. And message specifying means for specifying a message corresponding to the error type specified by the type specifying means based on the reference table, wherein the display means specifies information on the error that has occurred by the message specifying means. It is characterized by being displayed in association with the received message.
According to a fourth aspect of the present invention, in the programmable logic controller according to the first, second, or third aspect, the reference table acquisition means associates an error type or error level with an error handling operation. Based on the reference table, an error specifying unit that acquires a reference table and identifies an error to be canceled, and an error handling operation corresponding to the error type or error level of the error specified by the error specifying unit And a coping action specifying means for specifying the coping action and an instruction means for instructing execution of the coping action specified by the coping action specifying means.
According to the fifth aspect of the present invention, the reference table used at the time of error processing control in the programmable logic controller that performs sequence control by sequentially executing the program indicating the control contents based on the signal input from the connected device. Priority for error cancellation, which is an information processing device to be generated, which associates with the error type acquired by the type information acquisition unit, the type information acquisition unit that acquires information of the error type that occurs in the sequence control of the programmable logic controller An input screen displaying means for displaying an input screen for setting an error level indicating a degree, a setting accepting means for accepting an error level setting input from the input screen displayed by the input screen displaying means, and the setting accepting means The accepted error level is A generating means for generating a reference table associated with the error type, to achieve the second object by providing the.
According to the sixth aspect of the present invention, an error type for identifying a type of error in a programmable logic controller that performs sequence control by sequentially executing a program indicating control contents based on a signal input from a connected device A reference table acquisition function for acquiring a reference table associated with an error level indicating priority of error cancellation, an error information acquisition function for acquiring information on an error that occurred during execution of the sequence control, Based on the error information acquired by the error information acquisition function, the type specifying function for specifying the error type corresponding to the error that has occurred, and the memory for storing the error information acquired by the error information acquisition function in the storage device Function and the error level corresponding to the error type specified by the type specifying function The first object is achieved by realizing a level specifying function that is specified based on a reference table and a display function that displays information on the error that has occurred in association with the error level specified by the level specifying function. Achieve.
In the invention according to claim 7, the reference table used at the time of error processing control in the programmable logic controller that performs the sequence control by sequentially executing the program showing the control contents based on the signal input from the connected device. The information processing device to be generated has a type information acquisition function for acquiring information on an error type that occurs in sequence control of the programmable logic controller, and an error release priority associated with the error type acquired by the type information acquisition function. An input screen display function for displaying an input screen for setting an error level to be displayed, a setting reception function for receiving an error level setting input from the input screen displayed by the input screen display function, and a reception of the setting by the setting reception function The error level is A generating function for generating a reference table associated with the type, to achieve the second object by realizing.

According to the first aspect of the present invention, it is possible to provide a programmable logic controller capable of performing processing according to the error level by specifying the error level based on the reference table.
According to the invention of claim 4, an input screen for setting an error type and an error level corresponding to the error type is displayed, and a reference table is displayed based on the error type and the error level input from the input screen. By generating, an information processing apparatus capable of easily generating a reference table in which an error type and an error level are associated can be provided.
According to the fifth aspect of the present invention, it is possible to provide a control program capable of performing processing according to the error level by specifying the error level based on the reference table.
According to the invention described in claim 6, an input screen for setting an error type and an error level corresponding to the error type is displayed, and a reference table is displayed based on the error type and the error level input from the input screen. By generating, it is possible to provide a table creation program that can easily generate a reference table in which an error type and an error level are associated with each other.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS.
(1) Outline of Embodiment In the present embodiment, a PLC that performs sequence control by sequentially executing a program indicating control content based on a signal input from a specific input device, and a device connected to the PLC A sequence control system constituted by:
Connected to the PLC are input devices such as sensors and mechanical switches, output devices such as solenoid valves and motors, and programmable displays that function as input / output devices.
The PLC is connected to a PC for creating a program for executing a control operation of the PLC and the programmable display, various data, and the like. Programs and data created by the PC are stored in a storage device built in the PLC and used when executing sequence control.

In addition to the control operation program that executes the main control of the PLC, the PLC stores data such as an error processing program and an error information table that are used when dealing with errors that occur in the control of the PLC.
The error information table is data that is referred to when the error processing program is executed. For each error code, an error level indicating the priority of error cancellation, a message to be displayed when an error occurs, and the like are defined.
When an error occurs in the sequence control system, the PLC specifies an error level corresponding to the type (error code) of the generated error based on the error information table.
Then, based on the specified error level, the PLC rearranges information related to the generated error, such as a message assigned to the error code, and displays the information on the programmable display.
The PLC performs the process of canceling the generated errors in the order displayed on the programmable display, that is, in the order of higher error levels.

(2) Details of Embodiment FIG. 1 is a diagram showing a schematic configuration of a sequence control system according to the present embodiment.
As shown in FIG. 1, the sequence control system includes a PLC (programmable logic controller) 1, a programmable display 2, an input device 31, an output device 32, and a PC (personal computer) 4.

FIG. 2 is a diagram illustrating a configuration of the PLC 1 and a connection state of peripheral devices.
As shown in FIG. 2, the PLC 1 includes a storage device 11, an arithmetic device 12, a control device 13, an input / output I / F (interface) 14, an input circuit 15, and an output circuit 16.
The storage device 11 is a device for storing data and programs used for controlling the PLC 1, and is configured by a memory device such as a ROM (Read Only Memory) or a RAM (Random Access Memory).
The storage device 11 stores programs and data such as a control operation program 111, a display setting program 112, an error processing program 113, a communication program 114, an error information table 115, and a task program 116.
Further, the storage device 11 is provided with an error information storage area 117.

The control operation program 111 is a program for executing a control operation in the PLC 1.
This control operation program 111 is a program described in a dedicated ladder program language, and is described by combining a command word expressed by symbol (symbol) display based on a sequence diagram and device information. ing.
The display setting program 112 is a program for executing settings such as the screen layout and operation of the programmable display device 2.
Note that the display setting program 112 may be stored in a memory device built in the programmable display device 2, and settings such as screen layout and operation may be executed on the programmable display device 2 side.

The error processing program 113 performs error detection processing in the PLC 1 (sequence control system), storage (storage) processing of detected error information in the error information storage area 117, and arrangement of error information stored in the error information storage area 117. This is a program for executing processing related to errors such as replacement processing, display data output processing related to error information, and error cancellation processing.
The communication program 114 is a program that controls data (signal) communication between the PLC 1 and peripheral devices such as the programmable display 2, the input device 31, the output device 32, and the PC 4 connected to the PLC 1.

The error information table 115 is data that is referred to when the error processing program 113 is executed. The error information table 115 is a reference table that is used when executing rearrangement of error information stored in the error information storage area 117 or error cancellation processing. .
In this error information table 115, a correspondence relationship between an error code (error type) for specifying an error type and an error level (urgent level, importance level) indicating priority of error cancellation is shown.
The error information table 115 is a data table created (generated) in the PC 4 using a dedicated program. By changing the content of the error information table 115, error information displayed on the programmable display 2 is displayed. The order can be changed.

The task program 116 is a program for executing a specific sequence control operation (task) defined in advance.
This task program 116 has an identifier (address indicating a storage unit, task number, etc.) attached to each task, and executes a corresponding task when a task is specified during execution of the control operation program 111. The program 116 is configured to be read and executed.

The arithmetic device 12 is a device that performs processing at the center of the PLC 1, and includes a CPU (Central Processing Unit) such as a microcomputer.
The arithmetic device 12 executes programs such as the control operation program 111, the display setting program 112, the error processing program 113, the communication program 114, and the task program 116 stored in the storage device 11, thereby enabling internal devices and peripheral devices to be executed. The control unit receives data, calculates and processes the data, stores the data in the RAM in the storage device 11, and outputs a result.
The control device 13 is a device that executes control in the PLC 1 together with the arithmetic device 12.

The input / output I / F 14 is an interface for performing data (signal) communication between the PLC 1 and the PC 4. Data communication between the PLC 1 and the PC 4 can be performed using cable communication such as a USB (Universal Serial Bus) cable, infrared communication, or the like.
The input circuit 15 is an external device of the PLC 1 such as an output signal output from an input device 31 such as various sensors or mechanical switches installed on the device or the operation panel, or an operation signal input via the programmable display 2 ( This is a circuit device that captures an input signal from a peripheral device.

The output circuit 16 outputs a control signal to the output device 32 or the programmable display 2 based on the results of the control operation program 111, the display setting program 112, the error processing program 113, the task program 116, etc. executed in the arithmetic unit 12. Circuit device.
The PLC 1 configured as described above sequentially executes programs indicating control contents such as the control operation program 111, the display setting program 112, the error processing program 113, and the like based on signals input from the input device 31 and the programmable display 2. Perform sequence control by executing.

FIG. 3 is a diagram showing the configuration of the PC 4 and the connection state of peripheral devices.
As shown in FIG. 3, the PC 4 includes an information processing apparatus including a storage device 41, a calculation device 42, an input device 43, an output device 44, a control device 45, and an input / output I / F 46.
The storage device 41 is a device that stores data and programs used for control of the PC 4, and includes a memory device such as a ROM, a RAM, and a hard disk.
In the storage device 41, in addition to a program for executing system management of the PC 4 and an OS (operation system) that provides a basic operating environment, a setting parameter 411, a ladder creation program 412, a ladder change program 413, a display screen setting program 414 In addition, programs and data such as an error information setting program 415, a data conversion program 416, and a communication program 417 are stored.

The setting parameter 411 is various data given to processing executed by the PC 4, and is data required to specify data, command functions, and options specified when using a specific function.
The ladder creation program 412 is a program for creating the control operation program 111 for executing the control operation in the PLC 1.
The ladder change program 413 is a program that changes the contents of the control operation program 111 created by the ladder creation program 412.

The display screen setting program 414 is a program for creating a program for creating (setting) objects such as switches and lamps displayed on the display setting program 112 and the programmable display 2 and setting the screen arrangement of the objects.
The error information setting program 415 displays data constituting the error information table 115, for example, an error code, a message corresponding to the error code, and an error level input screen corresponding to the error code on the PC 4, and accepts input of the corresponding item. It is a program for.
The data conversion program 416 performs conversion processing based on the setting conditions input by the operator of the PC 4 via the input screen displayed by starting the error information setting program 415, and executes the error processing program 113 in the PLC 1 This is a program that creates (generates) an error information table 115 used in the process.
The communication program 417 is a program for controlling data (signal) communication between the PC 4 and peripheral devices such as the PLC 1 connected to the PC 4.

The arithmetic device 42 is a device that performs processing at the center of the PC 4, and is configured by a CPU (Central Processing Unit).
In the computing device 42, the OS program, setting parameter 411, ladder creation program 412, ladder change program 413, display screen setting program 414, error information setting program 415, data conversion program 416, communication program 417 stored in the storage device 41. By executing the program of the program, etc., the internal device and the peripheral device are controlled to receive the data, the data is calculated and processed, stored in the RAM in the storage device 41, the result is output, etc. Perform a series of actions.

The input device 43 is a device for inputting commands and data to the PC 4 and includes a keyboard, a mouse, a digital camera, a scanner, a tablet, a joystick, a video input device, a voice input device, a barcode reader, and the like.
It is also possible to take in (input) data from the outside of the PC 4, and in this case, a reading device for reading a storage medium storing the data functions as the input device 43. It is also possible to import (input) data into the PC 4 via a network such as the Internet.

The output device 44 is a device that outputs the processing result of the PC 4 to the outside, and is configured by a display, a printer, a plotter, a voice output device, or the like that outputs the processing result as characters, numbers, images, etc. that can be recognized by humans. Yes.
In this embodiment, a display is used as the output device 44, and an input screen when the ladder creation program 412, the ladder change program 413, the display screen setting program 414, etc. are executed on the display screen of this display. Is displayed.
The operator of the PC 4 inputs data such as parameters based on the contents displayed on the display.
The control device 45 is a device that executes control in the PC 4 together with the arithmetic device 42.
The input / output I / F 46 is an interface for performing data (signal) communication between the PLC 1 and the PC 4. Data communication between the PLC 1 and the PC 4 can be performed using cable communication such as a USB (Universal Serial Bus) cable, infrared communication, or the like.

Returning to the description of FIG. 1, the programmable display 2 connected to the PLC 1 has a man-machine interface function and functions as an input / output device of the PLC 1 described above.
The programmable display device 2 is a display that displays a screen set by the display setting program 112. In the present embodiment, a touch panel display device (hereinafter referred to as a touch panel) is used.
A touch panel is a device having a screen screen that enables pointing (selection) by directly touching a screen on which menu items or the like are displayed with a finger, for example, by including a pressure-sensitive or electrostatic panel. .
The programmable display device 2 may be configured by a liquid crystal display or a CRT (CRT) display that does not have a touch panel function. In this case, an input device such as a keyboard and a mouse for operating a cursor (pointer) on the screen is provided to select a switch such as a menu item to be displayed.

Next, a method for creating the error information table 115 used when executing rearrangement of error information stored in the error information storage area 117, error cancellation processing, and the like will be described.
In the present embodiment, the error information table 115 is configured such that data created (generated) in the PC 4 is transmitted to the PLC 1. Here, a method for creating the error information table 115 in the PC 4 is described. explain.
The error information setting program 415 is activated on the PC 4.
The PC 4 obtains prediction error data stored in advance in the PC 4 or the PLC 1 or data such as the task program 116, and the types of errors that may occur for each unit based on the obtained data ( (Type) is specified and an identification number (error code) is attached.

In the present embodiment, an error code is designated for each task defined (set) in the task program 116. In this embodiment, one error can be processed per task.
A system error in the sequence control system, that is, an internal error of the PLC 1 is configured to be processed as a fixed error code.
The PC 4 displays a message (Message) assigned to the error code (Code) and an error level (Level) setting screen (editing screen), that is, an input screen on the display.

FIG. 4 is a diagram showing an example of a message and error level setting screen for each error code.
The message and error level are set for each error code (number) using an input form as shown in FIG.
The operator sets (inputs) a message to be assigned to the corresponding error code (Code) in the message (Message) setting area of the setting screen.
Hereinafter, the content of the message is abbreviated as “Error Message *”, but actually, for example, “Unit 01 / Standby Pallet / Detection Sensor Err”, “Unit 01 / Pallet / Feed Pin Err”, etc. The unit number where the error occurred, the control object, the outline of the error, etc. are briefly shown. The number of characters in the message is preferably a value that takes into account the specifications of the display (programmable display 2).
In the present embodiment, the maximum number of characters in a message is set to 30 half-width characters and 15 full-width characters.

Subsequently, the operator sets (inputs) an error level to be assigned for each error code in the error level (Level) setting area of the setting screen.
The error level indicates the degree of priority (emergency, importance) of error cancellation. In the present embodiment, errors A to E are assigned in order from the error having the highest priority, that is, the error having the highest urgency or importance. It is shown in five levels using the alphabet.
That is, the error level with the highest error release priority (urgentness, importance) is indicated by “A”, and the error level with the lowest error release priority (urgency, importance) is indicated by “E”. Show. If the error level setting condition is unknown, the error level is temporarily indicated by “F (other)”.

Although not shown, the setting screen can set (input) an error processing method (error handling operation) assigned for each error level.
Hereinafter, the content of the error processing method (error handling operation) is abbreviated as “error processing *”, but in practice, for example, “system emergency stop (forced stop) processing”, “cycle stop processing”, Corresponding processing methods such as “alarm processing” and “continuous operation processing” are shown.
In this embodiment, an error processing method (error handling operation) is assigned for each error level. However, when more detailed settings are required, the error processing method is set for each error code. You may make it allocate.

The PC 4 accepts the operator settings (inputs) on the error level and error processing method setting screen described above for each error code and stores them in the storage device 41.
Then, after the settings relating to all error codes (or error codes whose settings are to be changed) are completed, the data conversion program 416 is activated on the PC 4.
Then, the setting (input) data stored in the storage device 41 is converted, and the error information table 115 is created (generated).
FIG. 5 is a diagram illustrating an example of the error information table 115.
The condition setting data set by the operator includes a data table in which error messages assigned to error codes and error levels are arranged in the order of error code numbers, as shown in FIG. The error processing method assigned to the error level as shown in (2) is converted into an error information table 115 including a data table arranged in the order of the error level.

Next, an error display control operation for causing the programmable display 2 to display the status of an error that has occurred in the sequence control system according to the present embodiment will be described.
FIG. 6 is a flowchart showing a processing procedure of an error display control operation for displaying the status of the generated error on the programmable display 2.
When the power is turned on to the PLC 1, the arithmetic device 12 reads the control operation program 111, the display setting program 112, and the error processing program 113 from the storage device 11 and activates them.

When each program is executed in the PLC 1, the arithmetic unit 12 determines whether an error has occurred in the sequence control system, that is, whether an error has been detected (step 11).
Note that errors in the sequence control system, that is, errors occurring in the PLC 1 and peripheral devices (connected devices) are error signals and task programs 116 transmitted (input) from the input device 31, the output device 32, the programmable display 2, etc. Can be detected based on the execution result (task processing result).

When no error is detected (step 11: N), the arithmetic unit 12 continues the error detection process.
On the other hand, when an error is detected in the sequence control system (step 11: Y), the arithmetic unit 12 specifies the error code of the error that has occurred based on the error signal and the execution result (task processing result) of the task program 116. (Step 12). The identification of this error code functions as a type identification unit.
The arithmetic unit 12 stores (stores) error information including the identified error code in the error information storage area 117 (step 13).

FIG. 7A is a diagram showing an example of a state in which error information is stored in the error information storage area 117.
As shown in FIG. 7A, error information and error codes are stored in the error information storage area 117 in the FIFO method (first-in first-out method), that is, in the order in which errors occur.
In this embodiment, the error occurrence time, the task number at which the error result is output, the error code, and the like are stored in the error information storage area 117 as information on the error that has occurred.

Subsequently, the arithmetic device 12 refers to (reads out) the error information table 115 stored in the storage device 11, and the error level assigned to the error code in each error information stored in the error information storage area 117. Is identified (step 14).
Then, the arithmetic device 12 stores the specified error level in the error information storage area 117 as error information.
As shown in FIG. 7B, the arithmetic unit 12 sorts the error information stored in the error information storage area 117 and associated with the error code and the error level based on the error level (step 15). Specifically, the error information is rearranged in descending order of priority of error cancellation (urgentness, importance), that is, “A”.
Information on errors of the same error level is rearranged in order of the error occurrence time.
The sorted error information is stored in an area different from the area where the information is first stored by the FIFO method.

Next, the computing device 12 refers to (reads out) the error information table 115 stored in the storage device 11 and is assigned to the error codes of the sorted error information in the error information storage area 117 (correspondence). (Step 16). The identified message data is stored in the error information storage area 117 in association with the error code.
And the arithmetic unit 12 displays the specified error message on the programmable display device 2 in a state of being sorted (reordered) by the error level (step 17).
The arithmetic unit 12 reads out not only the error message but also information on the error accompanying the error message, that is, information on the error code for specifying the error message from the error information storage area 117 and displays the information on the programmable display 2.

FIG. 8 is a diagram illustrating an example of a screen of the programmable display 2 that displays an error message.
As shown in FIG. 8, the programmable display 2 includes error information such as an error code, an error level, an error occurrence time, task information in which an error is detected, in addition to an error message related to an error that has occurred in the sequence control system. Are displayed in a sorted state in descending order of error level.
The error information displayed on the programmable display 2 can be arbitrarily set. For example, only the error message and the error level can be displayed.

Further, as shown in FIG. 8, the programmable display 2 is provided with a “reset” button for the operator to input a request (instruction) for each error to cancel the corresponding error (error reset). Yes.
In addition to the “reset” button for individually indicating such a request for canceling the generated error, the programmable display 2 “automatic reset” for automatically executing the processing for canceling the generated error in descending order of error level. "Button.
As described above, in the sequence control system according to the present embodiment, the error cancellation processing (reset processing) that has occurred is executed in descending order of urgency, or the error selected by the operator is executed in order. Can do.
Even if the “automatic reset” button is not operated (pressed), it is possible to set in advance that the error cancellation processing is executed in descending order of the error level.

Returning to the description of FIG. 6, the arithmetic device 12 subsequently determines whether or not the PLC 1 is being activated (step 18). The determination as to whether or not the PLC 1 is being activated can be made based on, for example, the power supply management state or program execution state in the PLC 1.
When the PLC 1 is being activated (step 18: Y), the arithmetic unit 12 returns to the process of step 11 and continues the error detection process.
On the other hand, when the PLC 1 is not activated (step 18: N), for example, when the PLC 1 is in a standby state, the processing is ended as it is.

As described above, according to the present embodiment, the information on the error that has occurred is displayed on the programmable display 2 in the order of high error level, that is, in the order of high priority of error cancellation (urgentness, importance). Can do.
As a result, the operator (system administrator) confirms the display content of the programmable display 2 so that, for example, the occurrence of an error with a high degree of urgent error cancellation, the type of error that is occurring, and the like. Can be easily grasped.
Since the operator can easily recognize the priority of the error handling process based on the error information displayed on the programmable display device 2, appropriate management should be performed when an error occurs in the sequence control system. Can do.

Next, an error cancellation (error reset) method in the sequence control system according to the present embodiment will be described.
FIG. 9 is a flowchart showing a processing procedure of an error canceling operation in the sequence control system.
First, the computing device 12 of the PLC 1 determines whether or not there is a request for error cancellation (error reset) (step 21).
Here, for example, an operation (pressing) signal of a “reset” button for inputting an error cancellation request transmitted from the programmable display 2 shown in FIG. 8 described above, or automatically in the order of higher error level. The presence or absence of an operation (pressing) signal of the “automatic reset” button for execution is detected.
Note that if the error information setting program 415 is set in advance to perform error cancellation processing in descending order of error level, it is determined that there is a request for error cancellation (error reset).

If there is no error reset request (step 21: N), the arithmetic unit 12 continues the error reset request detection process.
On the other hand, when there is a request for error reset (step 21: Y), the arithmetic unit 12 identifies an error that is a target of error reset (step 22). Here, for example, an error code and an error level of an error to be reset are specified.
Subsequently, the computing device 12 refers to (reads out) the error information table 115 stored in the storage device 11 and identifies an error processing method corresponding to the identified error (step 23).
Here, the error processing method is specified with reference to a table in which the error level and the error processing method are associated with each other as shown in FIG.

Next, the arithmetic unit 12 instructs execution of the corresponding error canceling process based on the specified error processing method (step 24). Here, for example, the cancellation (termination) of the task in which the corresponding error has occurred is instructed.
Then, after instructing the execution of the error release process (reset process) or after the error release process (reset process) is completed, the arithmetic unit 12 clears (erases) the display of the corresponding error on the programmable display 2. (Step 25).
Subsequently, the arithmetic device 12 determines whether or not the PLC 1 is being activated (step 26).
When the PLC 1 is being activated (step 26: Y), the arithmetic device 12 returns to the process of step 21 and continues the detection process of the error cancellation (error reset) request.
On the other hand, if the PLC 1 is not activated (step 26: N), the process is terminated as it is.

As described above, according to the present embodiment, by setting automatic reset (automatic release) in advance, the error levels are ordered in descending order, that is, error cancellation priority (urgentness, importance) is high. In order, it is possible to execute an appropriate cancellation process (corresponding process) corresponding to the generated error level (or error code).
According to the present embodiment, by providing a “reset” button for individually instructing an error cancellation request as shown in FIG. 8, for example, setting of error cancellation (return) for each task (routine) Therefore, the convenience for the operator can be improved. In addition, it is possible to execute an appropriate process corresponding to the error occurrence state.
According to the present embodiment, the information related to the generated error and the programmable display 2 are associated with each other, so that the efficiency of developing error processing technology in the sequence control system can be improved.

The error processing technique as described above can be used not only when actual control is performed on a production line or the like, but also at the stage of development of a sequence control system such as simulation of a control process (test process).
In the sequence control system development stage, for example, in the program development stage, there are many defects (bugs) in the program, so many errors occur in the test process due to such bugs. End up.
When this embodiment is applied at the time of error handling processing in such a test process, errors generated based on the error information table 115 are rearranged in the order of error levels and displayed on the display of the programmable display 2 or the PC 4. .
As a result, the system developer can visually check the importance (error level) of errors that occurred in the test process, and can process errors that occurred in the test process in descending order of importance. Therefore, error processing can be performed efficiently. Therefore, the development efficiency of the system can be improved.

It is the figure which showed schematic structure of the sequence control system which concerns on this Embodiment. It is the figure which showed the structure of PLC and the connection state of a peripheral device. It is the figure which showed the structure of PC, and the connection state of peripheral devices. It is the figure which showed an example of the setting screen of the message for every error code, and an error level. It is the figure which showed an example of the error information table. It is the flowchart which showed the process sequence of the error display control operation which displays the condition of the produced | generated error on a programmable display. It is the figure which showed an example of the information of the error stored in an error information storage area. It is the figure which showed an example of the screen of the programmable display which displayed the error message. It is the flowchart which showed the process sequence of the error cancellation | release operation | movement in a sequence control system.

Explanation of symbols

1 PLC
2 Programmable display 4 PC
11 Storage Device 12 Arithmetic Device 13 Control Device 14 Input / Output I / F
DESCRIPTION OF SYMBOLS 15 Input circuit 16 Output circuit 31 Input device 32 Output device 41 Memory | storage device 42 Arithmetic device 43 Input device 44 Output device 45 Control device 46 Input / output I / F
111 Control operation program 112 Display setting program 113 Error processing program 114 Communication program 115 Error information table 116 Task program 117 Error information storage area 411 Setting parameter 412 Ladder creation program 413 Ladder change program 414 Display screen setting program 415 Error information setting program 416 Data Conversion program 417 Communication program

Claims (7)

A programmable logic controller that performs sequence control by sequentially executing a program indicating control contents based on a signal input from a connected device,
A reference table acquisition means for acquiring a reference table in which an error type for specifying an error type and an error level indicating priority of error cancellation are associated with each other;
Error information acquisition means for acquiring information of an error that occurred during execution of the sequence control;
Based on the error information acquired by the error information acquisition means, a type specifying means for specifying an error type corresponding to the error that has occurred,
Storage means for storing information on the error acquired by the error information acquisition means in a storage device;
Level specifying means for specifying an error level corresponding to the error type specified by the type specifying means based on the reference table;
Display means for displaying information on the generated error in association with the error level specified by the level specifying means;
A programmable logic controller comprising: Based on the error level specified by the level specifying means, the error information stored in the storage device is provided with a sorting means for sorting the information in descending order of priority,
2. The programmable logic controller according to claim 1, wherein the display unit displays information on the error that has occurred based on the order rearranged by the rearrangement unit. The reference table acquisition unit acquires a reference table in which an error type, an error level, and a message related to an error are associated with each other,
Message specifying means for specifying a message corresponding to the error type specified by the type specifying means based on the reference table;
The programmable logic controller according to claim 1, wherein the display unit displays information on the error that has occurred in association with the message specified by the message specifying unit. The reference table acquisition means acquires a reference table in which an error type or error level is associated with an error handling operation,
An error identification means for identifying an error to be canceled;
A coping operation identifying unit that identifies an error coping operation corresponding to the error type or error level of the error identified by the error identifying unit based on the reference table;
Instruction means for instructing execution of the coping action specified by the coping action specifying means;
The programmable logic controller according to claim 1, 2, or 3. An information processing apparatus that generates a reference table used in error processing control in a programmable logic controller that performs sequence control by sequentially executing a program indicating control contents based on a signal input from a connected device. ,
Type information acquisition means for acquiring information of an error type that occurs in sequence control of the programmable logic controller;
An input screen display means for displaying an input screen for setting an error level indicating the priority of error cancellation, which is associated with the error type acquired by the type information acquisition means;
Setting accepting means for accepting the setting of the error level input from the input screen displayed by the input screen displaying means;
Generating means for generating a reference table in which the error level received by the setting receiving means is associated with an error type;
An information processing apparatus comprising: To the programmable logic controller that performs sequence control by sequentially executing the program showing the control contents based on the signal input from the connected device,
A reference table acquisition function for acquiring a reference table in which an error type for specifying an error type and an error level indicating priority of error cancellation are associated with each other;
An error information acquisition function for acquiring information on an error that occurred during execution of the sequence control;
A type specifying function for specifying an error type corresponding to the error that has occurred, based on the error information acquired by the error information acquiring function;
A storage function for storing information on the error acquired by the error information acquisition function in a storage device;
A level specifying function for specifying an error level corresponding to the error type specified by the type specifying function based on the reference table;
A display function for displaying information on the error that has occurred in association with the error level specified by the level specifying function;
Control program to realize. To an information processing device that generates a reference table used during error processing control in a programmable logic controller that performs sequence control by sequentially executing a program indicating control content based on a signal input from a connected device,
A type information acquisition function for acquiring information of an error type that occurs in sequence control of the programmable logic controller;
An input screen display function for displaying an input screen for setting an error level indicating the priority of error cancellation, which is associated with the error type acquired by the type information acquisition function;
A setting reception function for receiving the setting of the error level input from the input screen displayed by the input screen display function;
A generation function for generating a reference table in which an error level received by the setting reception function is associated with an error type;
A table creation program for realizing

Images