JPS62251804A - Sequence control device - Google Patents

Abstract

PURPOSE:To prevent a sequence control device from misoperation at the change of its contents by displaying process transfer conditions, processes and respective definitions of outputs on one CRT. CONSTITUTION:Data are defined by using the CRT screen with a sequence control operation difining format to attain sequence control. In the sequence control operation, each process is transferred to the succeeding one at the formation of a prescribed condition and logic circuits with pattern numbers are registered in the system as conditional patterns. The pattern numbers of conditional patterns to be used out of respective patterns are set up in the pattern number setting columns 1, 2 of a conditional pattern definition part and coupling relation and set conditions are set up and defined in respective columns 3-5. When a prescribed condition is provided at a prescribed process, only the prescribed process is set up and displayed in one CRT display device so that the process and information to be outputted at that time are informed and the prescribed control operation is executed on the basis of the displayed information.

Description

[Detailed description of the invention] [Technical field to which the invention pertains]

The present invention relates to a sequence control device that can be applied to various plants such as steel, chemical, electric power, and food plants.

[Prior art and its problems]

Sequence control is usually defined as "control in which each stage of control is sequentially advanced in accordance with a predetermined order or condition." Therefore, it can be said that not only the input-output relationship of the sequence control circuit that performs the control, but also the causal relationship within the circuit is clear. However, the objects of sequence control are valves, electric motors, pumps, etc.
Because the states are expressed qualitatively as open, closed, activated, or stopped, academic systemization has lagged behind. Therefore, the design of sequence control circuits is based solely on the designer's ``kan'' or ``experience.'' The current situation is that there are a large number of systems that are tied to the same system, and that their control methods are not unified. On the other hand, the development of microcomputers has been remarkable recently.
Sequence control devices are also shifting from relays and timers to microcontrollers with built-in microcomputers. One of the advantages of adopting such a microcontroller is that it can be used to program sequences (
An example of this is the ease of change, in that the program can be easily changed. However, it is not always easy to assemble this program without errors, and therefore there has been a desire for a sequence control device that can easily make such changes.

[Purpose of the invention]

The present invention has been made in view of the above, and it is an object of the present invention to provide a highly reliable sequence control device using a CRT display device that can easily and quickly respond to any changes without error. .

[Key points of the invention]

The key points of the present invention are a process transition condition definition section that selects necessary logic circuit patterns from various logic circuit patterns prepared in advance, and sets the connection relationships and conditions for each of the selected logic circuit patterns; It is equipped with a CRT display device that displays on the same screen a process definition section that sets the process number and process name that operate under the transition conditions, and an output definition section that sets the operation output for each process. When a predetermined condition is given in a process, it sets only the predetermined process, knows the process and the information that should be output at that point, performs the predetermined control operation based on this, and furthermore, it The main point is that the sequence control system can be completed using a description method that allows the output to be clearly understood.

[Embodiments of the invention]

FIG. 2 is an explanatory diagram for explaining a certain sequence operation, and shows what is generally called a time chart. In the figure, the horizontal direction indicates steps (processes), and the vertical direction indicates controlled objects. Control items are shown in the control target column, and the blacked out parts indicate that they are output at each step. That is, in the sequence operation shown in FIG. 2, V SV −
113, F-402, and the input timer operate, the VSV-114 operates as a control target during the input process, and the F-402 operates as a control target during the mixing process. By the way, in the case of a sequence operation as shown in FIG. 2, in each step, when a predetermined condition is satisfied, the process moves to the next step. FIG. 3 is an explanatory diagram of a method of defining process transition conditions, and shows transition conditions to the "feeding" process in FIG. 2. According to the present invention, logic circuits are registered in the system with pattern numbers attached as condition patterns, as shown by (a) and (bl in FIG. 3. In FIG. The pattern number is 42.
(b), "R(7)" The pattern number is 21. Among these condition patterns, enter the pattern number to be used in the pattern number setting column of the condition pattern definition section as shown in Figure 3 (C). 1.2.Next, specify the combination of "Condition 1" and "Condition 2" in the combination relationship setting column 3, and finally define each condition of the condition pattern in the condition setting columns 4 and 5. . In the example of FIG. 3(C), pattern numbers 42 and 21 are set as condition 1.2, and their connection relationship is specified as AND. Also, 1 of each condition pattern
One condition is as shown in Figure 3 (contact A of the logic circuit of al).
, B, C, D, and E are "T t A-101HPC
3J, ------1, rST-IQ1 activation" is defined as "r12B mixer stop" as shown in FIG. If such a condition pattern is defined, the logic circuit shown in Figure 4 will be constructed.In addition, each process is defined, and this definition is expressed as a process explicit (as shown in Figure 5). number) 66 and a process name column 7. In the example shown in Fig. 5, the process name rST-1014 (
The process name (ST is an abbreviation of 5TEP) indicates "startup". Furthermore, the output is defined in each process, and this definition is shown in FIG. As shown in FIG. 6, the output definition consists of an output address setting field 8 indicating output address, timer selection, and module width, an output device name setting a9, and an operation setting field 10. The operation setting a10 indicates an output command, where Y indicates ON output specification to the device, F indicates flicker specification, and P indicates pulse output specification. The present invention provides such definitions of process transition conditions, process definitions,
This system is characterized in that output definitions are associated and displayed on a single CRT display device, and an example of a CRT screen at that time is shown in FIG. In the present invention, data is defined using a CRT screen in a sequence control operation definition format as shown in FIG.
Realize sequence control. In Figure 1, process transition conditions, process definitions, and output definitions are displayed in a format that makes the correspondence relationship clear.
When the AND or OR condition of ``Condition 1'' and ``Condition 2'' is satisfied, the process described below is performed, and the output is output to the device described as Y in the output definition section. Note that blank entry in the output definition section means stop.

【Effect of the invention】

According to the present invention, each definition of process transition conditions, processes, and outputs is displayed on the same CRT, so that the cause-and-effect relationship in the sequence control system can be clearly seen at a glance, and change mistakes that often occur when making changes can be prevented.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an example of a screen of a CRT display device according to the present invention, Fig. 2 is a time chart for explaining sequence operation, Fig. 3 is an explanatory diagram of setting process transition conditions, and Fig. 4 is a diagram showing process transition conditions. 5 is an explanatory diagram of process settings, and FIG. 6 is an explanatory diagram of output settings. 1.2- Pattern number setting field, 3--Connection relationship setting field, 4.5--Condition setting field, 6--Process number field, 7-
Process name field, 8--output address setting field, 9--output device name setting field, 10--operation setting field. pt Rijin I Rishi Yamaguchi Ura No. Z Figure $ 3 Sen No. 4 Mekoku 5 laps

Claims (1)

[Claims] 1) A process transition condition definition unit that selects necessary logic circuit patterns from various logic circuit patterns prepared in advance and sets their connection relationships and conditions for each of the selected logic circuit patterns;
Equipped with a CRT display device that displays on the same screen a process definition section that sets the process number and process name that operate under the process transition conditions, and an output definition section that sets the operation output for each process. A sequence control device characterized by: