JPH0444770B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a diagnostic method for early detection of whether a control device is operating normally or has stopped due to an abnormality or the like.

Conventional technology Conventionally, a sequencer registers multiple operation patterns of on/off states of input/output contacts using a random access memory storage area for diagnosis of a control device, and detects operations other than the registered patterns during operation. to detect abnormalities. There is also a dedicated pattern monitor for writing patterns into memory, reading out patterns to confirm whether the writing was done correctly, and pattern monitoring to display the pattern number when a predetermined pattern occurs. It has a program. Such prior art is clearly complex in construction and operation.

Purpose An object of the present invention is to provide a method for diagnosing a sequencer with a simple configuration.

Configuration The present invention provides a sequencer that has a plurality of input contacts Detects the combination pattern of the logical states of input contact This is a sequencer diagnostic method characterized by the following.

Embodiment FIG. 1 is a block diagram that is the premise of the present invention. The sequencer includes an input device 1 that receives signals from external devices, an output device 2 that derives signals to the external devices, a control device 3 realized by a microcomputer, etc., and a display device that displays diagnostic results. 4 is provided. The input device 1 has input contacts, the output device 2 has output contacts, and the control device 3 includes internal relays implemented by a memory, such as a random access memory.

FIG. 2 is a flowchart showing the operation of the sequencer. Move from step n1 to step n2,
Performs operations such as initializing the system, cutting off output contacts, and cutting off internal relays. At step n3,
It performs so-called programmer processing such as processing input keys and executing programmer functions. In step n4, it is determined whether or not a sequence program is being executed. If it is being executed, the process moves to step n5, and the contact information of the input device 1 is stored in the store area of the control device 3.

FIG. 3 shows a memory map of the random access memory included in the control device 3. The logic state of input contact X and the logic state of internal relay CR are:
They are written to their corresponding store areas.
In step n5, the input contacts X are written into the store areas corresponding to each input contact, as shown in FIG.

At step n6, execute the sequence command,
The effect is written to the store area of output contact Y and internal relay CR. In step n7, the output is read out to the output device 2 from the output area corresponding to the output contact Y. With conventional sequencers,
After this step n7, return to n3. According to the present invention, after step n7, a pattern check processing operation consisting of steps n8 and n9 is performed. internal relay
A portion of CR and output contact Y is also used as a pattern check relay. A pattern check relay is a pattern check relay that, when a combination of logic states such as input contact It gets turned on as it gets older. In step n8, it is diagnosed whether the pattern check relay is ON or OFF. When the pattern check relay is ON, the process moves to step n9, and the display device 4 displays the number of the pattern corresponding to the pattern check relay that is ON. When the pattern check relay is OFF and after the pattern number is displayed, the process returns to step n3.

For example, assume that internal relay CR7 and output contact Y7 are used as a pattern check relay as shown in FIG. At this time, input contact X0 turns ON, output contact Y0 turns OFF, and output contact
If Y2 is ON, internal relay CR7 as a pattern check relay will be ON. As a result, the pattern number corresponding to internal relay CR7 as a pattern check relay is displayed on display 4.
Displayed by. In addition, output contact Y7 as a pattern check relay turns ON when input contact X1 is OFF and input contact X2 is ON.
Output contact as this pattern check relay
The pattern number corresponding to Y7 is displayed on the display device 4.

In the above configuration, since the internal relay CR and the output contact Y are used as the pattern check relay, there is no special reference to the storage area of the random access memory for storing patterns. As a result, memory capacity can be reduced.

Alternatively, the pattern check relay may use another storage area of the memory, such as a random access memory included in the control device 3.

In the above configuration, the pattern check relay in the ON state is monitored and the pattern number is displayed. However, in one embodiment of the present invention, the pattern check relay changes from OFF to ON a predetermined number of times. When the pattern check relay is selected, the pattern number corresponding to that pattern check relay is displayed. For this reason, in this embodiment, instead of the configuration of step n8 in FIG. When the number of operations has reached a predetermined number, the process moves to step n9, where the number of the pattern corresponding to the pattern check relay is displayed, and the number of operations is determined. If the number of times is less than the predetermined number, step
Configure to go back to n3. The other configurations are the same as those shown in FIGS. 1 to 4 described above. In this way, the pattern check relay
When the operation from OFF to ON occurs a predetermined number of times, the number of the pattern corresponding to that pattern check relay is displayed.
It is possible to easily detect patterns according to the purpose of use of the sequencer, which expands the range of applications.
Moreover, even if a plurality of pattern check relays are set, by displaying the number of the pattern in which the above-described operation has occurred a predetermined number of times, it is possible to easily distinguish it from other patterns.

Effects As described above, according to the present invention, the output contact Y or a part of the internal relay CR is operated as a check relay, and the combination pattern of the logic states of the input contact X, the output contact Y, and the internal relay CR in the store area is determined. Detection requires no special program or configuration for pattern diagnosis. Furthermore, memory capacity can be reduced. Similar to conventional sequencers, patterns can be registered by inputting a program using, for example, ladder symbols, which simplifies the configuration and facilitates operation.

Further, according to the present invention, since the display is performed when a predetermined pattern is detected a predetermined number of times,
It is easy to detect patterns according to the intended use of the sequencer. Furthermore, when a check relay operation is performed, a corresponding number is displayed, so even if a plurality of patterns are set, it is easy to distinguish the pattern in which the condition has been realized.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic configuration of the present invention, FIG. 2 is a flowchart for explaining its operation, and FIG. 3 is a diagram showing a random access memory and a memory map included in the control device 3. FIG. 4 is a program diagram showing the operation of the pattern check relay. 1... Input device, 2... Output device, 3... Control device, 4... Display device.

Claims (1)

[Claims] 1. Input contact X, output contact Y, and internal relay
In a sequencer that has multiple CRs and a store area where these logical states are written, output contact Y or a part of the internal relay CR operates as a check relay, and input contact A method for diagnosing a sequencer, characterized in that a combination pattern of logical states of a relay CR is detected, and when a predetermined pattern is detected a predetermined number of times, a number corresponding to the detected pattern is displayed.