JP2522057B2 - Distributed control system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a control station installed in a process, an operator station for monitoring the control station, and an engineering station for editing a sequence program or the like. Relates to a distributed control system configured by interconnecting communication lines, and in particular, the sequential function chart (SFC; Sequential) set in this distributed control system.
Function Chart) to improve the monitoring of the execution status.

<Prior art> Recently, in the sequence control field of processes, factories, etc., a sequential function chart (SFC; Sequential Funct), which is also called GRAFCET
(Ion Chart) has recently attracted attention and there is a trend toward standardization.

This Sequential Function Chart is
A series of sequence control is described by using step numbers, graphic elements, etc. as shown in FIGS.

FIGS. 4 (a) and 4 (b) show an example of editing the sequence processing using the sequential function chart on the CRT screen of the engineering station.

Step number in FIG. 4 (a) In step 2, "preparation" processing is performed, and when the condition is met with the graphic element "+" (transition), the step number Proceed to step, perform the "heating" process, and when the condition is satisfied with "+", step number The "mixing" process is executed, and the sequence process is edited in the same manner.

Here, each process of “preparation”, “heating”, and “mixing” set in each step number 1, 2, 3 is a normal sequence described in sequence processing language, ladder diagram, sequence table, etc.・ It is a program.

Also, FIG. 4 (b) is a step number And the step number Is an example of parallel operation, and a sequence program is set corresponding to each step number, as in FIG. 4 (a).

The sequential function chart thus edited is downloaded from the engineering station to the control station when it is completed, and is executed by the control station when the operation is started. Also, by displaying this sequential function chart on the operator station, the operator can see the entire sequence.

As described above, since the sequential function chart is described by combining graphic elements, process names, etc., it is easy to construct sequence control and the sequence process can be grasped as a whole.
It is extremely effective.

<Problems to be solved by the invention> However, the constructed sequential function chart is displayed on the CRT or the like of the operator station in the system, and the operator can grasp the entire sequence, but the control operation actually starts. Then,
By marking “•” or the like near the step number as in step number 2 in FIG. 4 (a) or step number 5 in FIG. 4 (b), or by highlighting the block near the step number. Since the progress status of the sequence was displayed, the operator does not have any information on how much the processing sequence corresponding to the step number has progressed or what is causing when the sequence is congested. There was a problem that the discovery of was delayed.

An object of the present invention is to solve the above problems, and it is an object of the present invention to configure a system so that the sequence progress status can be grasped in detail even when a sequential function chart is used.

<Means for Solving the Problems> The present invention is to detect the sequence progress status corresponding to the sequential function chart from the control station and display it in a window on the operator station, and its outline is as follows. .

The present invention is directed to at least one control station installed in a process to execute various control operations, an engineering station for editing sequence control in a sequential function chart and downloading to the control station, and the control station. At least one operator who manages the station and displays the sequential function chart on the CRT.
In a distributed control system comprising a station and a station, the operator station is provided with a step number of the sequential function chart currently executed in the control station and a sequential function of a hierarchical structure set to the step number. A control unit for detecting a chart or a program line of a processing sequence set to this step number and various information related to this line, and the step number of the sequential function chart currently being executed in the control station With a window display function, the window display area is set on the CRT screen according to the operator's instruction and the sequential structure of the hierarchical structure set to the step number is displayed.
In a distributed control system, a function chart or a program line of a processing sequence set to this step number and a display control unit for displaying various information related to this line in the window display area are provided. is there.

<Operation> The distributed control system of the present invention has a sequential operation on the operator station during execution of the sequence processing.
Highlights the position of the step currently in progress in the function chart, and optionally windows the current execution line of the sequence processing program and the associated information corresponding to this step in progress.

<Embodiment> FIG. 1 is a conceptual diagram of the configuration of a distributed control system embodying the present invention.

The operator uses the engineering station 1 to create a sequential function chart (hereinafter referred to as “SFC”) as shown in FIGS. 4 (a) and 4 (b). At this time, each step in this SFC may be programmed in a generally known sequence processing language, but each step may be further edited in SFC so that the SFC has a hierarchical structure. That is, for example, the sequence processing corresponding to step number 2 in FIG. 4 (a) can be expanded to the SFC as shown in FIG.
May be edited.

When the SFC is created, the SFC is downloaded from the engineering station 1 via the communication line 2 to the control station 3 installed in the process 4.
Upon receiving this SFC, the control station 3 converts it into a predetermined sequence processing language in a program format and stores it inside.

The operator station 5 has a CRT 51 and a display control section 52 having a window display function. The control section 53 has a processor for realizing various functions such as a communication function and a control station management function in the operator station 5 and its processor. It is a block including peripheral circuits.

In this figure, engineering station 1,
In the example, one control station 3 and one operator station 5 are connected to the communication line 2, but the system may be composed of a plurality of units.

Now, it is assumed that a predetermined control operation is started according to the SFC set in the control station 3.

Operator station 5 during sequence control operation
When it becomes necessary to know the control operation status of the control station 3, the operator displays the SFC of the control station 3 on the CRT 51 by operating the keyboard or the like.
A display screen as shown in the figure is displayed.

At this time, the control unit 53 of the operator station 5 detects the step number of the SFC executed in the control station 3 via the communication line 2, and the display control unit 52 highlights the position of this step number on the CRT 51. .

In this example, Is currently being executed and is highlighted by changing the display color as indicated by the diagonal lines.

Further, in the system of the present invention, the control line 53 of the operator station 5 is set to the step number 2 and the currently executed program line, and various information such as variables and data handled by this line are also stored. Collecting.

The operator uses the window display function set in the display controller 52 of the operator station 5 when he / she wants to know more detailed information about the step number 2.

This window display function causes the operator station 5 to display a window screen as shown in FIG. 3 on the CRT 51. The position of this window screen may be anywhere on the CRT screen shown in FIG. 2, but it should be a position that is easy for the operator to see.

It is a major feature of the system of the present invention that the detailed information of the sequence processing set to the designated step number is displayed on this window screen.

In the window screen of FIG. 3, the step number "■ STEP 2" currently being executed is the title, and information relating to the program line currently being executed at this step number is displayed as follows.

"Preparation EXECUTING STATEMENT (description of execution line) LINE: 15 (line 15): compare (comparison instruction) REF. (Reference item) FIC100A SUM: 10000000 (accumulated value of tag FIC100A is 1000000
0) LINE: 20 (line 20): drive (moving command) REF. (Reference item) HV3631B PV: 0 (tag HV3631B valve opening 0) PREVIOUS NEXT (display comment)・
Program lines 15 "compare" and 20
It can be seen that “drive” (drive command) is being executed in parallel, and the reference item “REF.” Indicates that the current integrated value of the tag number FIC100A in the compare command compare on line 15 is 10
000000, which is the drive command drive for program line 20
It is found that the current valve opening degree of the tag number HV3631B is 0 degree.

Thus, in the system of the present invention, when the SFC entire display screen is displayed on the CRT 51 of the operator station 5, the position of the step number currently being executed is highlighted,
Further, the window display function is set to display the execution line of the processing sequence program currently being executed in the step and its detailed information.

Further, the hierarchy display screen may be set so that the window screen is further expanded to the SFC display. At this time, the SFC as shown in FIGS. 4 (a) and 4 (b) is displayed on the window screen.

<Effects of the Invention> According to the distributed control system of the present invention, even when the sequential function chart SFC is used, the step number currently being executed and the program execution in the sequence processing corresponding to this step number are executed. Since detailed information about the line and this program line can be obtained from the window screen, the sequence progress can be easily grasped accurately, and the cause of the process abnormality such as sequence congestion can be quickly found.

Also, by referring to this window screen, if the sequence condition is not satisfied and the sequence is congested, skip this program line and specify another step number and program line. Process control can proceed.

[Brief description of drawings]

FIG. 1 is a structural example of a distributed control system according to the present invention, FIG. 2 is an overall view of an SFC of a CRT 51 of an operator station 5 in the system of the present invention, and FIG. 3 is the window shown in FIG. The display diagram when expanded, and FIGS. 4A and 4B are examples of the sequential function chart. 1 ... Engineering station, 2 ... Communication line, 3 ... Control station, 4 ... Process, 5 ... Operator station, 51 ... CRT, 52 ... Display control unit, 53 ... Control unit.

Claims (1)

(57) [Claims] 1. At least one control station installed in a process to execute various control operations; an engineering station for editing sequence control by a sequential function chart and downloading the sequence control to the control station; At least one operator who manages the control station and displays the sequential function chart on the CRT.
In a distributed control system comprising a station and a station, the operator station is provided with a step number of the sequential function chart currently being executed in the control station and a hierarchical function having a hierarchical structure set to the step number. A control unit that detects a chart or a program line of a processing sequence set to this step number and various information related to this line, and the step number of the sequential function chart currently being executed in the control station With a window display function, the window display area is set on the CRT screen according to the operator's instruction and the sequential structure of the hierarchical structure set to the step number is displayed.
A distributed control system comprising a function chart or a program line of a processing sequence set to this step number and a display control unit for displaying various information related to this line in the window display area.