JPS63273904A - Runaway detecting device for sequence controller - Google Patents

Abstract

PURPOSE:To detect the runaway of an individual program without disturbing the functions of both general and individual controls, by providing a setting part, a resetting part and a deciding part for flag bits. CONSTITUTION:A flag bit setting part 6 has a flag bit corresponding in 1:1 to each C mode individual program and sets '1' to all flag bits via a processor 2 every time an S mode general program is started. A flag bit resetting part 7 has a flag bit corresponding in 1:1 to each C mode program and produces a resetting signal when the execution is through. A flag bit deciding part 8 decides whether a flag remains or not at the part 6. If the presence of the remaining flag '1' is confirmed, the part 8 produces an alarm signal and displays a specific one of C mode programs C1-C10 that has runaway at a display part 10 including a lamp 11 and a CRT 12.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sequence controller used for monitoring and controlling various plants, and particularly to detecting runaway in a sequence controller having multiple operation modes (or control modes). Regarding equipment.

[Conventional technology]

Generally, general-purpose sequence controllers (synonymous with sequencer or programmable controller) have two types of control modes.

One is called the S mode, which operates according to a sequence program that matches the control purpose of the sequence controller and controls the basic operations of the sequence controller. The other one is called the C mode, which operates by a sequence program (written in C language) for individually controlling the control target according to the startup command of the S mode program, and consists of a plurality of programs.

The above S mode and C mode are each executed by separate and independent processors, but as mentioned above, since C mode is started by S mode, C mode is dominated by S mode, and therefore the control in the sequence controller is led. The right will be on the C mode side.

On the other hand, the sequence controller has an abnormal operation self-diagnosis function to ensure control reliability. There are various abnormality detection methods, but one known example is a method that includes a watchdog timer function and a function that checks the operating status of each controller in the link status of multi-interfaced sequence controllers (programmable Controller, Published by Denkishoin, October 25, 1981). Another example is the calculation processing time of the program, which is monitored by an external measurement unit that monitors the response time (speed). A method for detecting whether a series of sequence operations (S mode operation) has ended is known (Japanese Patent Application Laid-Open No. 8471-1989).
Publication No. 2).

[Problem that the invention seeks to solve]

As described above, the sequence controller is equipped with various abnormality detection devices, but since all of them detect abnormalities related to S mode operation, they are incomplete in detecting abnormalities of the sequence controller as a whole. That is, since the C mode is dominated by the S mode, the sequence stops when an S mode failure occurs, but conversely, if there is an abnormality on the C mode side, the abnormality cannot be detected on the S mode side. This is because the S mode only activates the C mode, and their operations are independent of each other. Therefore, it is necessary to detect the abnormal execution of the C mode program by some means.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sequence controller runaway detection device that can reliably detect runaway of a program in C mode in a sequence controller having S mode and C mode.

[Means for solving problems]

The above purpose is to provide an integrated control unit that has an integrated program (S mode) that performs integrated sequence control of controlled objects, and a plurality of integrated control units that are activated by a startup command of the integrated program (S mode) and that individually sequence control each controlled object. an individual control unit having an individual program (C mode); a flag unit that sets a flag in a flag pit corresponding to each individual control unit when the overall program (S mode) is started; a flag reset unit that resets a flag corresponding to the individual control unit that ended at the end of execution of each of the individual programs (C mode); and a flag of the flag set unit after the end of execution of the individual control program (C mode) has elapsed. and a display section that displays an abnormality based on the output of the flag determining section when a flag remains in the flag setting section.

[Effect]

According to the configuration of the present invention described above, a flag pit corresponding to each individual control section is set when the general program is started, and the flag is reset when the program execution of each individual control section is completed.

After the execution of each individual control program is completed, the remaining flags are checked, and if there are any remaining flags, it is assumed that the individual control program is running incorrectly and an abnormality is displayed.

In this way, runaway in one individual control program can be detected independently without interfering with the respective control functions of integrated control and individual control, and the reliability of the sequence controller and control safety can be ensured. .

〔Example〕

Next, embodiments according to the present invention will be described based on the drawings.

FIG. 1 shows the main parts of a sequence controller and the configuration of an abnormality detection device according to the present invention.

In FIG. 1, a sequence controller 1 includes a processor for S mode control (hereinafter referred to as S mode processor) 2 and a processor for C mode control (hereinafter referred to as C mode processor) 3. The S-mode processor 2 activates the S-mode program at a predetermined activation cycle based on the clock signal from the clock signal oscillator 4. This clock signal is sent to the C-mode clock transmitter 22 of the C-mode processor 3 through the S-mode clock transmitter 5. Therefore, the C-mode program in the C-mode processor 3 operates in synchronization with the S-mode program in the S-mode processor 2. The C mode processor 3 has a plurality of C mode programs C1""Cn
, and each is controlled independently. The relationship between the above S mode processor 2 and C mode processor 3 is shown in FIG.

As shown in FIG. 2, the S-mode processor 2 executes the S-mode program every cycle T. Then, at each start-up (startup) of the S mode program, C
Each C mode program Cl"" of mode processor 3
Start Cn. Therefore, the S mode processor 2 has the initiative in controlling the entire sequence controller 1. The operating time of each mode program C1 to C11 is set in advance to be shorter than the operating time SON of the S mode program. Therefore, if any of the C mode programs C1-CD is operating for longer than the S mode operating time SON, it is an abnormality and can be considered as a runaway of the C mode program.

Next, the abnormality detection device in the sequence controller 1 described above will be explained. In FIG. 1, the abnormality detection device is
It is composed of a flag pit setting section 6, a flag pit resetting section 7, and a flag pit determining section 8. The flag pit setting section 6 has flag pits that correspond one-to-one to each of the C mode programs Cl"C,
Each time an S-mode program is started, the S-mode processor 2 uniformly sets flag 1'1'' in all flag pits. On the other hand, the flag pit reset unit 7 sets one-to-one flags for each of the C-mode programs Cn''-Cn. It has a corresponding flag pit, and outputs a reset signal for the corresponding flag pit at the end of execution of each C mode program CI-Cn, and supplies it to the flag pit reset section 7. Therefore, the entire C mode program C1-Cn
At the time when execution is completed, all flag pits in the flag pit reset section 7 should be uO''.The flag pit determination section 8 determines whether there is a remaining flag in any of the flag pits in the flag pit set section 6. Determine whether

Under normal conditions, all flags are "0", and no alarm is output in this case. If C mode program C1
-C, is activated even after the original C mode operation time has elapsed, the corresponding flag of the flag pit setting section 6 is still "1", and therefore the flag pit determination section 8 issues an alarm. Outputs a signal (eg, logic "1"). This alarm signal is sent to the alarm display section (
The program is given to the W-return pump 11 and the C:RT 12) 10, and it is displayed that one of the C mode programs C1''Cn is out of control and is abnormal.

On the other hand, a clock signal timeout detection section 9 is connected to the sequence controller 1. This clock signal timeout detection section 9 detects that the clock signal oscillated from the clock signal oscillation section 4 is sent to the S mode clock transmission section 5,
By taking in the clock signal via the mode clock transmission section 6 and monitoring the length and ON/OFF state of the clock signal, it is possible to detect whether the operation of the S mode processor 2 and the C mode processor 3 is normal or abnormal. The detection signal is output to the display section 10, and an abnormality display is also performed in the same manner.

Next, an example will be described in which the above-described abnormality detection device is used to control the opening and closing of (gates) such as water intake amount of a dam in a hydroelectric power plant. An example thereof is shown in FIG.

In FIG. 3, automatic gate opening and closing commands (C mode operation) are output from the calculation processing bag flf13.

The gate open/close manual command is output by pressing the gate open/close switch 14. This command is used by sequencer 1
It passes through the manual/automatic switching section 15, the gate open/close protection section 16, and the contact point of the output auxiliary relay 17, which connects the gate machine side panel 1.
Command 8 to open and close the gate. The state of the gate machine side panel 18 at that time is monitored by the gate abnormality detection section 19 in the sequencer, and if an abnormality is detected, it is transmitted to the gate open/close protection section 16 and the open/close command is locked. On the other hand, the opening degree of the gate is measured by a gate opening degree meter 20.

In the sequencer 1, the gate opening reading is received and monitored by the opening error code detection unit 21, and if there is an abnormality in the opening, an error code is detected and transmitted to the gate open/close protection unit 16 to issue an open/close command. Lock signal.

Under such control, the abnormality detection bag according to the present invention!
i! By equipping 100, the gate opens.

If there is an abnormality in the automatic closing command sequence, the abnormality is detected by the detection operation described above, an alarm is output to the display unit 10, and the breaker 21 is opened to stop the control.

〔Effect of the invention〕

As described above, according to the present invention, a sequence controller has an S mode that has control initiative and a C mode that is subordinate to the S mode.

It is possible to reliably detect runaway of a C mode program and improve reliability and safety of a sequence controller.

[Brief Description of the Drawings] Fig. 1 is a block diagram showing an embodiment of the present invention, and Fig. 2 is a block diagram showing an embodiment of the present invention.
Time charts 1 and 3 showing the operation timings of mode and C mode are block diagrams showing an example of application to water gate control. DESCRIPTION OF SYMBOLS 1... Sequence controller, 2... S mode processor, 3... C mode processor, 6... Flag pit set part, 7... Flag pit reset part,
8... Flag determination section, 10... Display section.

Claims (1)

[Scope of Claims] 1. An integrated control unit having an integrated program that performs integrated sequence control of controlled objects, and a plurality of integrated control units that individually sequence-control each controlled object activated by a startup command of the integrated program. an individual control unit having an individual program; a flag setting unit that sets a flag in a flag pit corresponding to each of the individual control units when the overall program is started; a flag reset unit that resets a flag corresponding to the terminated individual control unit; a flag determination unit that determines the state of the flag in the flag set unit after the execution end time of the individual control program has passed; A runaway detection device for a sequence controller, comprising: a display unit that displays an abnormality based on the output of the flag determination unit when the flag remains.