JPH02281301A - Trouble diagnostic device - Google Patents

Abstract

PURPOSE:To make an accurate and quick diagnosis by using a cycle diagram to independently start individual cycles by a start relay and comparing turning- on/off states of the output, the original end, and the arrival end of the cycle with each reference time. CONSTITUTION:Data related to the cycle number, the original end, the arrival end, the output element, and respective reference times to turning-on of the output, turning-off of the original end, and turning-off of the arrival end of each cycle constituting a sequence is preliminarily stored in a cycle diagram table 7 by a keyboard 5 with a CRT. The number of the relay which starts a cycle as the diagnosis object and data related to turning-on/off for start are stored in a start relay table 8. The signal of a timer 9 which counts each reference time and the state signal of a relay 2 which is inputted through an interface circuit 6 are compared with data in the table 8. With respect to the start cycle where both of them coincide with each other, trouble elements are diagnosed based on state signals of the original end, the arrival end, and the output element of the start cycle and time counting of each reference time of the timer 9.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a fault diagnosis device that diagnoses a fault in a controlled device controlled by a programmable controller based on a sequence program stored in a memory.

<Prior art> Conventionally, as this type of failure diagnosis device, for example,
There is one described in Japanese Patent No.-148178. This fault diagnosis device is attached to a programmable controller that controls a controlled device equipped with a human and an output element based on a sequence program stored in memory, and a cycle counter that counts cycle numbers according to the operation steps of the controlled device. The computer detects an abnormality by monitoring the cycle number of the cycle counter, and diagnoses the cause by searching the sequence program. Then, this computer uses its software to find the cause of the failure from the signal states of the output element and reaching end element of the operation step corresponding to the cycle number at the time of the abnormality occurrence, and selects a program corresponding to this failure cause from among the above sequence programs. At the same time, the found program is simulated to find the operation switching failure condition of the output element, and this failure condition is output to the alarm display section.

<Problems to be Solved by the Invention> However, in the conventional fault diagnosis device described above, a computer searches for a program corresponding to a cause of a fault from among a sequence program described in detail at the level of a ladder diagram (expanded connection diagram). Since it sequentially simulates the found program to find the operation switching failure condition,
The drawback is that the amount of software needed for this is enormous and that diagnosis takes a long time. In addition, if the sequence program, ie, the ladder diagram, which is stored in the memory of the programmable controller is made incorrectly, an accurate search for the cause of the failure cannot be made, and a correct failure diagnosis cannot be made.

Furthermore, since the above-mentioned conventional failure diagnosis devices are designed for the purpose of automatically diagnosing failures during actual operation of completed controlled equipment, abnormality diagnosis for each individual cycle when installed as equipment is not considered at all. It has not been. That is,
Although there is a manual button on the operation panel of the controlled device to start each cycle, the failure diagnosis device does not have a means for specifying only the cycle to be diagnosed, so it is virtually impossible to diagnose the failure for each cycle. In addition, the reference time set for each cycle for time monitoring is short because it only covers actual operation, and installations that require a long time to complete the cycle may be difficult to install even if the cycle is operating normally. There is a problem in that it is diagnosed as abnormal when the time is over.

On the other hand, as another fault diagnosis method, there is a learning method that stores the normal control state in memory and compares it with the current state to detect abnormalities. This is true only for the first time, and is of no use in diagnosing failures of individual cycles during equipment installation.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to use a diagnostic method based on a cycle diagram that is simpler than a ladder diagram, and to provide means for specifying and storing the starting relay of each cycle to be diagnosed along with its status, and the storage contents. It is an object of the present invention to provide a failure diagnosis device that can accurately and quickly diagnose failures in individual cycles at the time of installation, etc., with a small amount of software, by providing a means for comparing the actual state of a starting relay.

Means for Solving the Problems> In order to achieve the above object, a fault diagnosis device of the present invention diagnoses a fault in a controlled device controlled by a programmable controller based on a sequence program stored in a memory. a cycle diagram table storing data regarding the cycle number of each cycle constituting the sequence, the origin element, the destination element, the output element, each reference time from output on, origin off, and destination end on;
a starting relay table that stores data regarding the number and status of the starting relay that starts each cycle to be diagnosed;
An input section for inputting data into both of the above tables, a timer for measuring each reference time of each cycle stored in the above cycle diagram table, and a status signal of each starting relay inputted via the above programmable controller. is compared with the data in the starting relay table above, and for starting cycles in which both match, the original end of that starting cycle is inputted via the programmable controller.

It is equipped with an arithmetic device that diagnoses the cause of failure and failure element based on the status signals of the reaching end and the output element and the measurement of each reference time by the above-mentioned timer.

The cycle diagram table includes the cycle number of each cycle that makes up the control sequence input from the input section, the source end, the destination end, the output element, and the criteria for output on, source off, and destination end on. Data relating to time is stored, and the starting relay table stores data relating to the number and state of the starting relay that starts the cycle to be diagnosed that is input from the input section. When the start relays on the controlled equipment side are turned on and sequence control for a specific cycle begins, the calculation means compares the status signal of each start relay input via the programmable controller with the data in the start relay table. , for a startup cycle in which both coincide, the state signals of the output, source end, and arrival end elements of that cycle input via the programmable controller are determined based on the timing of a timer that sequentially measures each of the reference times of that cycle. For example, if the output is not turned on, there is an error in the ladder diagram, if the source end is not turned off, there is a problem with the source end, etc., and if the destination end is not turned on, it is determined whether the output is turned on, off, or not. After diagnosing the failure of the reaching end, etc., the cause of the failure, and the failure elements, wait for the next activation relay to be turned on.

<Example> Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

FIG. 1 is a block diagram showing one embodiment of the failure diagnosis device of the present invention. are the origin of the limit switch 1a, etc., the reaching end element, and the coil! A controlled device having output elements such as b and operating in sequence, 2 is activated by a push button switch on an operation panel (not shown), and is a plurality of activation devices that individually start each cycle of the controlled device i during installation, etc. relay, 3
4 is a programmable controller that controls the controlled device 1 and the starting relay 2 based on a sequence program stored in a memory (not shown); 4 is a failure diagnosis device that is connected to the programmable controller 3 and that diagnoses a failure of the controlled device 1; It is.

The failure diagnosis device 4 includes a programmable controller 3
and an interface circuit 6 for transmitting and receiving data to and from the CRT.
The cycle number of each cycle constituting the sequence inputted from the attached keyboard 5, the origin element, the destination element, the output element, each reference time T until the output is turned on, the origin is turned off, and the destination is turned on.1. A cycle diagram table 7 storing data regarding T t and T 3 (see FIG. 2), and a CRT
A starting relay table 8 stores data related to the number and status of the starting relay 2 that starts the cycle to be diagnosed, which is entered from the attached keyboard 5, and each reference time of each cycle stored in the cycle diagram table 7 is clocked. The state signal of each starting relay 2 inputted via the timer 9 and the interface circuit 6 is compared with the data of the starting relay table 8, and for starting cycles in which both match, the state signal is manually inputted via the interface circuit 6. The computer is comprised of a CPU as an arithmetic unit that diagnoses the cause of a failure or a failure element based on the status signals of the origin, arrival end, and output elements of the startup cycle and the measurement of each reference time by the timer 9.

FIG. 2 shows l constituting the sequence of the above-mentioned controlled equipment l.
The normal operation of the cycle is schematically shown. When this cycle is started by the starting relay 2 with the corresponding number, the output element 11 is turned on by the reference time T1 (see Fig. 2(a)). ), the workpiece W moves to the right and the origin 12 is turned off by the reference time T after the output element is turned on (see Fig. 2 (b)), and the origin is turned off. to the reference time T3, the workpiece W reaches the reaching end 13.
, and the reaching end turns on (see FIG. 2(e)).

The operation of the failure diagnosis device 4 having the above configuration will be described below with reference to FIG.

The operator uses the CRT keyboard 5 to input the cycle number, source end, destination end, output element, output on,
Each reference time T r , T from origin off to arrival end on
t and T 3 are stored, and the starting relay table 8 stores data regarding the number of the starting relay that starts the cycle to be diagnosed and the on/off state at the time of starting. Next, the activation relay 2 of the cycle to be diagnosed in the controlled device I during installation or the like is turned on by turning on the push button switch on the operation panel. Then, the programmable controller 3 operates the cycle, while the CPU 10 of the fault diagnosis device 4 reads the status signal of each starting relay 2 via the programmable controller 3 in step Sl, and the status signal read out in step S2 is used as the starting relay. It is determined whether or not they match the data in table 8, and if it is determined to be yes, the process proceeds to step S3, where each reference time T, , T, , T, of the matched cycle is read out from cycle diagram table 7.

Next, a reference time T1 until the output is turned on is set in the timer 7, and it is determined in step S4 whether the output element 2 is turned on before the timer 7 finishes timing T1 in step S5. And time T.

If the output element 11 is turned on within this time, it is determined to be normal and the process proceeds to step S6, where the timer 7 sets the reference time T until the origin is turned off.
, is newly set. On the other hand, when the time measurement of T is completed while the output element 11 is off, it is diagnosed that an abnormality has occurred in the output due to an error in the ladder diagram, etc., and this is displayed and output in step S7, and then step S! Return to Furthermore, the CPU 1 controls the origin 1 by the time the timer 7 finishes timing Tt in step S9.
2 is turned off or not is determined in step S8. If the origin 12 turns off within the time T, it is determined to be normal and the process proceeds to step 810, where the timer 7 is newly set with a reference time T until the arrival end is turned on. On the other hand, if the timing T is completed while the source end 12 is on, it is diagnosed that the source end 12 or the output element 11 is malfunctioning or there is a wiring error, and step Sl
After displaying and outputting this at l, return to step St.

Finally, in step S13, the CPU 1 sets the timer 7 to T,
It is determined in step S12 whether or not the reaching end I3 is turned on by the time the time measurement is completed. If the reaching end 13 is turned on within time T, it is determined to be normal and the diagnosis for that cycle is ended.

On the other hand, when the time measurement of T3 ends with the reaching end 13 being off, a failure or wiring error in the machine or reaching end 13 of that cycle is diagnosed, and this is displayed and output in step S14, and then the process returns to step Sl.

In this way, when the cycle started by turning on the pushbutton switch on the operation panel ends, the sequence is automatically stopped by the programmable controller 3, and if there is a failure in that cycle, the contents are displayed on the CRT keyboard 5 as described above. Since the information is displayed, the operator can immediately repair the malfunctioning part. Thereafter, when a new cycle is started by turning on the push button switch, the same fault diagnosis as described above is performed for that cycle.

In this way, in the present invention including the above-mentioned embodiments, a cycle diagram that is simpler than a ladder diagram is used to cause each cycle to perform a single operation using a starting relay, and the output, source end, and final end of the cycle are turned on and off. Since the status of each cycle is monitored based on each reference time and the causes and failure elements of each cycle are diagnosed, it is possible to accurately and accurately detect individual cycle failures during installation, etc. with less software than before. Can be diagnosed quickly.

It goes without saying that the present invention is not limited to the illustrated embodiment.

<Effects of the Invention> As is clear from the above explanation, the fault diagnosis device for controlled equipment controlled by the programmable controller of the present invention has the cycle number, original end, and destination end of each cycle in the cycle diagram table. , output element, output on, primitive off,
Stores data regarding each reference time until the reaching end is turned on,
In addition to storing data regarding the number and status of the starting relay that starts the cycle to be diagnosed in the driving relay table, the data for the cycle in which the actual status signal of the starting relay and the data in the starting relay table match is stored.

The arithmetic unit monitors the time based on the actual status signals of the reaching end and output elements and the measurement of each of the reference times mentioned above using a timer, and diagnoses the cause of failure and failure element, so less software is required than before. As a result, failures in individual cycles can be diagnosed accurately and quickly at the time of installation, etc.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the fault diagnosis device of the present invention, Fig. 2 is a schematic diagram showing the normal operation of the cycle configuring the sequence of the controlled equipment, and Fig. 3 is a schematic diagram showing the normal operation of the above-mentioned fault diagnosis device. It is a flowchart which shows the flow of processing. l...Controlled equipment, 2...Start relay 3...Programmable controller, 4...Fault diagnosis device, 5...
・・Keyboard with CRT・Cycle diagram table, 8・Drive relay table, 9・Timer, 10・
・・CPU0 Do, Patent applicant: Sharp Corporation, 1 representative patent attorney: Aohaku Ao, and 1 other person 61

Claims (1)

[Claims] (1) A failure diagnosis device that diagnoses failures in controlled equipment controlled by a programmable controller based on a sequence program stored in a memory, which includes the cycle number, origin element, and destination element of each cycle that constitutes the sequence. , a cycle diagram table that stores data regarding each reference time from output element, output on, source end off, and arrival end on, and a start table that stores data regarding the number and status of the starting relay that starts each cycle to be diagnosed. a relay table, an input section for inputting data into both of the above tables, a timer for measuring each reference time of each cycle stored in the above cycle diagram table, and each activation inputted via the above programmable controller. The relay status signal is compared with the data in the starting relay table, and for starting cycles in which both match, the status signals of the starting end, reaching end, and output element of the starting cycle input via the programmable controller and the above timer are A failure diagnosis device equipped with an arithmetic device that diagnoses the cause of failure and failure elements based on measurement of each reference time.