JP2962387B2 - Programmable controller and method for resetting specific other station in distributed control system using same, method for detecting cause of reset of other station, method for monitoring abnormal station, method for synchronously starting and method for synchronously stopping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a programmable controller having a data link function in a distributed control system for distributed control of a plurality of programmable controllers, a method for resetting a specific other station in a distributed control system using the same, and a method for resetting another station. The present invention relates to a reset factor detection method, an abnormal station monitoring method, a synchronous activation method, and a synchronous stop method.

[0002]

2. Description of the Related Art FIG. 14 shows a conventional programmable controller of this type. In FIG. 14, reference numeral 10 denotes a power supply unit, which includes a constant voltage circuit 11 and an abnormality detection circuit 12. 13 is a constant voltage circuit 11
A voltage of, for example, 5 V is output from the abnormality detecting circuit 12.

[0003] 100 is a CP for executing sequence processing and the like.
A U control unit 101 includes a CPU in the CPU control unit 100, a ROM 102 that stores an operating system programmer, a RAM 103 that temporarily stores data and the like, and a user program 104 that executes a sequence control. User memory stored, 1
05 is a data RAM for storing device information used in the user program, 106 is a reset switch for resetting the programmable controller system, 1
07 is an abnormality detection unit, 108 is a reset circuit unit, 109 is a buffer such as a data bus, and 110 and 111 are OR elements.

Reference numeral 200 denotes a data link control unit, 201 denotes a CPU, and 202 denotes a data link control unit.
0, a ROM storing an operating system program for controlling 0, a work RAM 203 for temporarily storing data and the like, a data link interface (data link I / F unit) 204, a reset circuit unit 205,
Reference numeral 207 denotes a two-port RAM for communicating with the CPU control unit 100. Reference numeral 300 denotes an I / O unit controlled by the CPU controller 100.

FIG. 15 is an explanatory diagram showing a system configuration in which a plurality of programmable controllers are connected using an optical cable or the like to execute distributed control. In the figure, reference numerals 30 (M master station) and 35 (L1 local Station), 4
0 (L2 local station) and 45 (L3 local station) are programmable controllers, 31, 36, 41,
46 is an optical cable, for example. Also, the following FIG.
6 to 19 are flowcharts for explaining the operation of the programmable controller configured as described above.

Next, the operation will be described. In FIG. 14 , a power supply unit 10 connected to an AC power supply (not shown)
Generates a voltage 13 of 5 V by an internal constant voltage circuit 11. The power supply unit 10 is connected as a power supply for driving the programmable controller. The user program created by the programming device (not shown)
User memory 10 via peripheral device I / F (not shown)
Therefore, when the power supply unit 10 is set to the ON state, the operating system program stored in the ROM 102 starts operating and executes the processing of the user program stored in the user memory 104. I do. That is, after executing an output refresh process described later (S50), ON / O of a limit switch (not shown) or the like connected to the I / O unit 300 is performed.
The FF information is read as input information, and the content is stored in the data RAM 105 as input image information (S51: input refresh processing).

[0007] Next, the user program stored in the user memory 104 is sequentially processed by the CPU 101 based on the input image information stored in the data RAM 105 (S52). The calculated result is
The information is sequentially stored in the RAM 105 as output image information. When the arithmetic processing of the user program is completed, a count-up for a device such as a timer (not shown) or a counter (not shown) is executed as an END processing (S53).

Next, a data link process (S54) is executed. For example, as shown in FIG. 15, communication data between the M master station 30 and the L1 local station 35, the L2 local station 40, and the L3 local station 45 is transmitted by an optical cable. 31,36,4
1 and 46. Details of the data link processing in step S54 will be described later. When the data link processing in step S54 ends, the data RA
The output image information stored in M105
01 is read, written to the I / O unit 300 via the buffer 109, and the output refresh processing is executed (S50). That is, the motor or solenoid (not shown) connected to the I / O unit 300 is turned ON / OFF.
It is turned off, and the control target (not shown) is controlled.

Next, the operation of the data link process in step S54 will be described with reference to FIG. M master station 3
0, the local stations 35 and 4 in the output image information calculated by the calculation processing in step S52.
The device information that needs to be transmitted to CPU
1 writes into the two-port RAM 207, and executes the output refresh processing (S55). Further, the CPU unit 101
Converts the received data from the local stations 35, 40, 45 into 2
The data is read from the port RAM 207, and the input refresh processing of the link data is completed (S56). At this time, as for the data received from the local stations 35, 40, and 45, it is assumed that the data received by the data link control unit 200 is written in the two-port RAM 207. The device information that needs to be transmitted to the local stations 35, 40, and 45 is transmitted to the local stations 35, 40, and 45 by the data link control unit 200.

Next, the operation of the data link control unit 200 will be described with reference to FIG. When the power supply unit 10 is turned on in the same manner as the CPU control unit 100, the operating system program stored in the ROM 202 starts operating, and the device information transmitted from the local stations 35, 40, and 45 is transmitted to the data link I / F. It is received via the unit 204 (S57). The received device information from the other station is written into the 2-port RAM 207 by the CPU unit 201 and becomes input image information of the other station that can be used by the CPU control unit 100 (S58: input refresh processing). Similarly, the output image information written into the two-port RAM 207 by the CPU control unit 100 is
The data is read out by the PU unit 201 (S59: output refresh processing) and transmitted via the data link I / F unit 204 as device information of the own station (S60).

Although the operation of the programmable controller has been described with the M master station 30 as its own station, the same operation is performed when the own station is, for example, the L1 local station 35, so that distributed control can be performed comprehensively. Configuration.

The abnormality detection signal 14 output from the power supply unit 10 and the forced reset signal 118 output from the reset switch 106 are transmitted to the CPU control unit 100.
And data link control unit 200, I / O unit unit 300
Is reset, and similarly, the WDT signal 11 output from the abnormality detection unit 107 which detects an arithmetic abnormality
Numeral 7 is configured to reset the I / O unit 300.

FIG. 19 is a flowchart for explaining the operation of monitoring the operation state of another station. For example, data is received by the data link I / F unit 204 of the M master station 30 (S61), and the CPU 201 determines whether the received data has an error (S62). Here, when it is determined that there is an error in the received data, it is determined whether or not to execute a retry process (S63). For example, the preset number a is compared with the error number n, and when it is determined that the error number n is smaller than the preset number a, a retry process is executed (S64), and conversely, If it is determined that the number of errors n is greater than the preset number a, it is determined that the other station is abnormal, and error processing corresponding thereto is performed (S65).

[0014]

Since the conventional programmable controller is configured as described above, in a distributed control system in which a plurality of programmable controllers are connected by an optical cable or the like, for example, one of the local stations has some kind of abnormality. In the event of a downtime, it is necessary to go to the location where the relevant local station is installed and perform a reset operation or the like to restore the local station, which is troublesome to restore and reduces the work efficiency. there were.

When a plurality of distributed stations start up with different power supplies, for example, when the power supply of one local station is turned on later than the power supply of the master station, the local station is determined to be abnormal and the system operates normally. Despite being
In the distributed control system (see FIG. 15) in which the distributed system does not start normally and the loop is continued, even if one of the stations becomes an abnormal station, the entire system goes down, and the operating efficiency of the system decreases. there were.

The present invention has been made in view of the above, and enables recovery work without going to a place where a local station that has gone down due to an abnormality is installed, thereby improving work efficiency, and improving a plurality of distributed stations. Even if the station starts up with another power source, the distributed system is started normally, and furthermore, in the distributed control system in which the loop is continued, 1
Programmable controller capable of preventing the whole system from going down due to a station becoming an abnormal station and improving system operation efficiency, and a method for resetting a specific other station in a distributed control system using the same, resetting another station It is an object to obtain a factor detection method, an abnormal station monitoring method, a synchronous activation method, and a synchronous stop method.

[0017]

To achieve the above object, according to the Invention The programmable controller according to the present invention,
Power supply unit, CPU control means, data link control means, I /
In a programmable controller constituted by O control means, the power supply section has an abnormality detection means for detecting an abnormality of the power supply and outputting a power supply reset signal;
The control means has reset switch means for outputting a forced reset signal for forcibly resetting the device, the data link control means resets a data link interface for communicating with another station, and resets the CPU control means and the I / O control means. Reset means for resetting the data link control means, wherein the reset means of the data link control means includes a power reset signal output from abnormality detection means of the power supply unit and the CPU
The reset signal is output based on the forced reset signal output from the reset switch means of the control means.

In the distributed control system according to the next invention,
That resetting of a particular other station, in the distributed control system for executing the distributed control by connecting a plurality of the programmable controller, specifies the other Tsubonepu Rogura <br/> Ma logic controllers that require resetting, said other Tsubonepu the reset command log llama logic controllers and data transmission, the remote station
Oite to receive the reset command, to generate a reset signal based on the reset command, by the reset signal, at least a CPU control unit of the other stations and I /
This is for resetting the O control means.

A programmable controller according to the next invention
Over La, a power supply, CPU control unit, the data link control unit, in a programmable controller configured by the I / O control unit, the power supply unit detects a power failure, the abnormality detecting means for outputting a power reset signal Have
The CPU control means includes reset switch means for outputting a forced reset signal for forcibly resetting the device and an abnormal reset signal output due to an abnormality such as a calculation traffic zone. A data link interface for communicating with a station, reset means for resetting the data link control means, wherein the reset means of the data link control means performs control based on an I / O reset signal for resetting the I / O control means And
It outputs a reset signal.

A programmable controller according to the next invention
Over La, a power supply, CPU control unit, the data link control unit, in a programmable controller configured by the I / O control unit, the power supply unit detects a power failure, the abnormality detecting means for outputting a power reset signal Have
The CPU control means includes reset switch means for outputting a forced reset signal for forcibly resetting the device and an abnormal reset signal output due to an abnormality such as a calculation traffic zone. A data link interface for communicating with a station, reset signal generating means for resetting the CPU control means and I / O control means,
Resetting means for resetting the data link control means, reset factor status information storing means for storing a factor for activating the resetting section, reading means for reading a reset factor from the reset factor status information storing means, The reset means of the link control means is an I / O for resetting the I / O control means.
A reset signal is input, and an interrupt signal to the control means and a reset signal are output.

In the distributed control system according to the next invention,
That the reset factor detection method other station, in the distributed control system for performing a connection to a distributed control a plurality of programmable controllers, a reset signal generated by such anomalies in other Tsubonepu log llama logic controllers, said reset signal the other Tsubonepu resets at least CPU control unit and I / O control unit of the log llama Bull the controller to generate an interrupt signal to the data link control means in said other Tsubonepu log llamas logic controllers by the reset signal by, wherein the interrupt signal other Tsubonepu stores factor of said reset signal in the log Lama Bull the controller, and the data link control means for a predetermined time reset after storing the reset factor, the data link in the other Tsubonepu log llama logic controllers transmits an abnormal signal in via the interface, the other Tsubone以Of at self Tsubonepu log llama logic controllers, receives the abnormal signal of the other station, the rear abnormal signal reception, the other Tsubonepu reset factor request signal for requesting reset source log llama Bull the controller via the data link interface send Te, receiving said reset source request signal, sends a reset factor are stored, via the data link interface of the self Tsubonepu <br/> log Lama Bull within the controller at the other Tsubonepu log Lama Bull the controller Receives the reset factor.

A programmable controller according to the next invention
Over La, a power supply, CPU control unit, the data link control unit, in a programmable controller configured by the I / O control unit, the power supply unit detects a power failure, the abnormality detecting means for outputting a power off signal a, the data link control means comprises a data link interface to communicate with another station, the reset signal generating means for resetting the CPU control unit and I / O control unit, a power supply switching means for switching to backup power supply, the data The power switching means of the link control means switches from the power supplied from the power supply part to the backup power supply by a power supply cutoff signal from the abnormality detection means of the power supply part, and at the same time, the data link control means by the power supply cutoff signal At least the data link interface can be operated by the backup power supply It is intended to.

A programmable controller according to the next invention
Over La, a power supply, CPU control unit, the data link control unit, in a programmable controller configured by the I / O control unit, the power supply unit detects a power failure, the abnormality detecting means for outputting a power off signal A data link interface having specific data detection means for detecting reception of specific data communicating with another station; reset signal generation means for resetting the CPU control means and I / O control means; Reset means for resetting the data link control means, reset factor status information storing means for storing a factor for activating the reset means, reading means for reading a reset factor from the reset factor status information storing means, power supply switching to a backup power source Control the entire means and data link control means Control means, a storage means for storing a program for executing the control processing by the control means, a storage means for storing results and data executed by the control means, and a power supply for the data link control means. The switching unit is configured to switch from the power supply supplied from the power supply unit to the backup power supply in response to a power supply cutoff signal from the abnormality detection unit of the power supply unit, and at least the control unit in the data link control unit by the power supply cutoff signal. , storage means, and the standby state memory means by said backup power supply, and operable at least data link interface in the data link control unit, the data link interface, wherein the specific data detection unit that will receive specific data By doing so, at least the control means, the storage means, and the storage It is to the operating state of the stage from the standby state.

In the distributed control system according to the next invention,
That faulty station monitoring method, Oh the distributed control system for executing the distributed control by connecting a plurality of programmable controllers
The power supply of the AC power supply is detected, the power supply supplied from the AC power supply and the backup voltage are switched by the detected power supply cutoff signal, and communication with another station programmable controller is performed by the backup voltage switched by the switching. Means for controlling at least the entire data link control means of the data link control means at the same time as enabling the data link interface to operate, storage means for storing a program for causing the control means to execute control processing, and the control means The storage means for storing the result and data executed by the in the standby state, receiving specific data from the other station programmable controller, by receiving the specific data at least control means in the data link control means, storage means, From storage to standby It is intended to be operable by the serial backup voltage.

A programmable controller according to the next invention
The controller is a programmable controller including a power supply unit, a CPU control unit, a data link control unit, and an I / O control unit. The system includes a start permission flag section, system activation means for activating a distributed control system constituted by a plurality of programmable controllers, and system stop permission means for giving a system stop permission command to the distributed control system.

In the distributed control system according to the next invention,
That the synchronization startup method, there the distributed control system for executing the distributed control by connecting a plurality of programmable controllers
The sequence processing is started by the synchronization start permission flag, and after the synchronization start permission flag is permitted, the synchronization start processing of the programmable controller that executes a predetermined sequence processing and the synchronization start of the distributed control system are started. Monitoring the standby state of the other station programmable controller, and after the other station programmable controller is in standby,
A system start command is transmitted, the system start processing of the system start command station programmable controller in the distributed control system in which the synchronous start permission flag of the own station is set to the enable state, and the system start command is received from the system start designated station programmable controller. In the distributed control system in which the synchronization start permission flag of the own station is set to the enable state, the system start processing of the receiving station programmable controller is executed.

In the distributed control system according to the next invention,
That fractured method, there the distributed control system for executing the distributed control by connecting a plurality of programmable controllers
Te, allow the system stop, the other station programmable controller determines whether or not the normal operation, when the other station programmable controller is in normal operation, sends a system stop permission command, synchronous start permission flag of the local station To a non-permitted state, and after setting the synchronous start permission flag to a non-permitted state, turning off the power of the own station to stop the system of the designated station programmable controller, and receiving the system stop permission command from the designated station programmable controller. Then, after receiving the system stop permission command, the synchronous start permission flag of the own station is set to the non-permitted state, and after the synchronous start permission flag is set to the non-permitted state, the power supply of the own station is turned off. And a stop process.

[0028]

In the programmable controller according to the present invention, the reset means of the data link control means includes a power reset signal output from the abnormality detection means of the power supply unit and a reset signal.
It becomes active by the forced reset signal output from the reset switch means of the PU control means.

In the distributed control system according to the present invention, the method of resetting a specific other station includes specifying a different station (n station) programmable controller which needs resetting,
The other station (n station) transmits the reset command of the programmable controller by data, the other station (n station) receives the reset command, generates a reset signal based on the reset command, and outputs the reset signal to the other station (n station). ) Reset at least the CPU control means and the I / O control means.

Further, in the programmable controller according to the present invention, the reset means of the data link control means may include:
It is activated by an I / O reset signal for resetting the I / O control means, and outputs a one-shot pulse as a reset signal.

Further, in the programmable controller according to the present invention, the reset means of the data link control means may include:
An I / O reset signal for resetting the I / O control means is input, and an interrupt signal to the control means and a one-shot pulse are output as a reset signal after a lapse of a certain time.

Further, the method for detecting a reset factor of another station in the distributed control system according to the present invention is a method for executing distributed control by connecting a plurality of programmable controllers. A reset signal is generated due to an abnormality or the like, and at least the CPU control means and the I / O control means in the other station (n station) programmable controller are reset by the reset signal, and the other station (n station) is reset by the reset signal.
An interrupt signal is generated in the data link control means in the programmable controller, the cause of the reset signal is stored in another station (n station) programmable controller by the interrupt signal, and the data link control means is reset for a predetermined time after storing the reset cause. An abnormal signal is transmitted via the data link interface in the other station (n station) programmable controller, and an abnormal signal of the other station (n station) is received by the own station (a station) programmable controller other than the n station. Then, after receiving the abnormal signal, a reset factor request signal for requesting a reset factor in the other station (n station) programmable controller is transmitted via the data link interface.
(Station) The reset cause request signal is received in the programmable controller, the stored reset cause is transmitted, and the reset cause is received via the data link interface in the own station (a station) programmable controller.

Further, in the programmable controller according to the present invention, the power supply switching means of the data link control means may include:
At the same time as switching from the power supplied from the power supply unit to the backup power supply according to the power supply cutoff signal from the abnormality detection means of the power supply unit, at least the data link interface in the data link control means can be operated by the backup power supply with the power supply cutoff signal .

Further, in the programmable controller according to the present invention, the power supply switching means of the data link control means may include:
The power supply is switched from the power supplied from the power supply unit to the backup power supply according to the power supply cutoff signal from the power supply abnormality detection means, and at least the control means, storage means, and storage means in the data link control means are switched to the backup power supply by the power supply cutoff signal. To a standby state, and at least a data link interface in the data link control unit is made operable. When the specific data detection unit receives the specific data, at least the control unit, the storage unit, and the storage unit are in a standby state. Change from state to operating state.

Further, according to a method of monitoring an abnormal station in a distributed control system according to the present invention, in a distributed control system in which a plurality of programmable controllers are connected to execute a distributed control, a power cut of an AC power supply is detected, and the detected power failure is detected. The power supply cutoff signal switches between the power supply supplied from the AC power supply and the backup voltage, and the backup voltage switched by the switching enables the data link interface communicating with the other-station programmable controller and at the same time at least stores data in the data link control means. A control unit for controlling the entire link control unit, a storage unit in which a program for executing the control process by the control unit is stored, and a storage unit for storing a result and data executed by the control unit in a standby state; Other station programmable controller It receives a specific data from the rollers, at least the control means in a data link control means by the reception of the specific data, storage means, and operable by a backup voltage storage means from the standby state.

Further, in the programmable controller according to the present invention, the data link control means is activated by synchronizing with the programmable controller of another station by the synchronous start permission flag, and the distributed control constituted by the plurality of programmable controllers by the system activation means. The system is started, and a system stop permission command is given to the distributed control system by the system stop permission means.

According to a synchronous start method in a distributed control system according to the present invention, in a distributed control system for executing distributed control by connecting a plurality of programmable controllers, a sequence start is started by a synchronous start permission flag, and the synchronous start is started. After the permission flag is enabled, a synchronous start process of the programmable controller that executes a predetermined sequence process,
Starts the distributed control system synchronously, monitors the standby state of the programmable controller of another station, sends a system start command after the programmable controller of another station becomes standby, and sets the synchronous start permission flag of the local station to the enabled state. System start command system in control system System start method for programmable controller, system start receiving station programmable in distributed control system receiving system start command from system start designated station programmable controller and setting synchronous start enable flag of own station to enable state Execute the system startup processing of the controller.

Further, according to the method for stopping synchronization in a distributed control system according to the present invention, in a distributed control system in which a plurality of programmable controllers are connected to execute distributed control, system stop is permitted, and the other-station programmable controller is operating normally. After determining whether or not the other-station programmable controller is operating normally, transmitting a system stop permission command, setting the synchronization start permission flag of the own station to the non-permission state, and setting the synchronization start permission flag to the non-permission state. The system stop processing of the designated station programmable controller that turns off the power of the own station, the system stop permission command from the designated station programmable controller is received, and after the system stop permission command is received, the synchronization start permission flag of the own station is disabled. And set the synchronization start permission flag to the non-permission state. Executes the system stop processing of non-designated stations programmable controller to turn OFF the own station power.

[0039]

[Embodiment 1] FIG. 1 is a block diagram showing a schematic configuration (embodiment 1) of a programmable controller according to the present invention. It has the same function as the function described above, and a description thereof will be omitted. The structure of this embodiment, in which the reset signal generating circuit 206 to the data link control unit 200 are added to the programmable controller in prior art shown in FIG. 14. Further, the basic operation is the same as that of the conventional example, and the description thereof is omitted.

As shown in FIG. 15, when the M master station 30 and the local stations (L1 to L3) 35, 40, and 45 are connected to execute distributed control, for example, the CPU control unit of the L1 local station 35 100 is WDT due to some abnormality
When the signal 117 becomes active, the I / O reset signal 114 becomes active via the OR element 110 and becomes
The O unit 300 enters a reset state. At this time,
The CPU control unit 100 is in an abnormal state .

The abnormality of the CPU control unit 100 is caused by the 2-port R
In order not to execute the RD / WR processing of the AM 207 (the data link processing shown in FIG. 17), the data link control unit 200 is configured to interrupt the data link control processing shown in FIG. Further, the interruption of the data link control processing of the L1 local station 35 may be, for example,
The M master station 30 detects that the L1 local station 35 is abnormal. In this state, the M master station uses a personal computer (not shown).
It is usually possible to connect the information to the maintenance person or the like. In this state, conventionally, it is necessary to go to another factory or the like where the L1 local station 35 is installed and reset and restore the L1 local station 35. In this embodiment, As described above, the recovery operation can be performed at the place where the M master station 30 is installed.

That is, an abnormal station is designated on a personal computer connected to the M master station 30. Next, a reset command for the designated abnormal station (for example, the L1 local station 35) is instructed on the personal computer. That is, a reset command of the L1 local station 35 is transmitted from the M master station 30 via the optical cable 31 by a maintenance person or the like.

The reset command transmitted from the M master station 30 is transmitted to the data link I / F section 204 of the L1 local station 35.
And the CPU 2 of the data link control unit 200
01, it is determined that the own station (the L1 local station 35 in this case) is the own station reset command. Next, the CPU 201
The reset signal generation circuit 206 is activated, and the local station reset signal 116 is output. Own station reset signal 11
6 is connected to the CPU control unit reset signal 119 via the OR element 113, and as a result, the reset unit 108 in the CPU control unit 100 becomes active. That is, the active state of the reset unit 108 is
The CPU 101 is reset, and the abnormal state is released.

As described above, according to this embodiment, it becomes possible to return a programmable controller installed in another factory or the like to a normal state in a centralized control room such as an office, so that downtime can be reduced and loss cost can be reduced. It can contribute to minimization.

[Embodiment 2] FIG. 2 is a block diagram showing a schematic configuration (embodiment 2) of a programmable controller according to the present invention. For example, when the CPU control unit 100 becomes abnormal as shown in FIG. 1 and when the data link control unit 200 receives a control power supply from the power supply unit 10, the CPU control unit 100 A case where the relationship with the link control unit 200 is close will be described.

When the CPU control unit 100 goes out of control, the data link control unit 200 may also run out in the same manner. That is, the CPU control unit 100 becomes abnormal and L1
When the local station 35 becomes an abnormal station, the M master station 30 detects an abnormality of the L1 local station 35 and transmits a reset command to the L1 local station 35 as in the first embodiment. However, since the CPU 201 of the data link control unit 200 of the L1 local station 35 is also abnormal due to runaway, the reset command cannot be received. This problem is solved as follows.

That is, a reset circuit section 205a for resetting the data link control section 200 by the I / O reset signal 114 is provided, and the reset signal output from the reset circuit section 205a is a one-shot pulse.

Next, the operation will be described. When the CPU control unit 100 becomes abnormal and the WDT signal 117 becomes active, the I / O reset signal 11
4 resets the I / O unit 300, and the CPU controller 100 also resets.
At this time, the CPU 201 of the data link control unit 200 is also in an abnormal state. However, the I / O reset signal 1
Since 14 is input to the reset circuit unit 205a, the abnormal state of the CPU 201 is set to the reset state.

At this time, since the reset circuit unit 205a is configured to output a one-shot pulse as a reset signal, the reset state of the CPU 201 is released. That is, the data link control unit 200 enters an abnormal state due to noise or the like, but is forcibly set to a reset state, and returns to a normal state after a lapse of a certain time (after a lapse of a one-shot pulse). Therefore, M
The reset command from the master station 30 is set in a receivable state. Other operations are the same as those in the first embodiment.
Description is omitted. At this time, the CPU control unit 100
Normally, the I / O unit 300 is controlled so that it is not automatically restored (since data and the like are connected to the I / O unit 300, the I / O unit 300 is normally released by the maintenance person's will). Is done).

Third Embodiment FIG. 3 is a block diagram showing a schematic configuration (third embodiment) of a programmable controller according to the present invention. In this embodiment, when an abnormality or the like occurs in the programmable controller and the I / O unit unit 300 is reset, the cause is determined by the M master station 30.
And a programmable controller capable of transmitting the information to other stations.

A status information reading unit 209 is added to the configuration of the programmable controller shown in FIG.
To the input, for example, a local station reset signal 116, a WDT signal 117, and a forced reset signal 118 are connected as reset factors. The reset circuit unit 205b of the data link control unit 200 outputs an INT signal 210 that operates as an interrupt signal to the CPU 201 and a data link control unit reset signal 211 that resets the data link control unit 200, as outputs. . The basic operation is the same as that of the conventional example or the other embodiments described above, and thus the description is omitted.

Next, the operation will be described. When the CPU control unit 100 becomes abnormal and, for example, the WDT signal 117 becomes active, as in the case shown in FIG.
The reset signal 114 becomes active, and sets the I / O unit 300 to a reset state. At this time, the I / O reset signal 114 is simultaneously output to the data link control unit 20.
0 is input to the reset circuit unit 205b,
The NT signal 210 becomes active.

Since the reset circuit section 205b includes a delay circuit 401 and a one-shot circuit 402 as shown in FIG. 4, the reset circuit section 205b is determined in advance by the delay circuit 401 after the INT signal 210 becomes active. After a lapse of time, a one-shot signal is output by the one-shot circuit 402 and becomes a reset signal 211 of the data link control unit 200.

Next, the INT signal 210 is sent to the CPU 201.
Is connected as an interrupt input to the
When “0” becomes active, the CPU 201 executes a predetermined interrupt process. That is, in order to execute the INT process shown in FIG. 5, the interrupt process first reads the status information from the status information reading unit 209 (RD) to detect a reset factor (S10). In this case, since the WDT signal 117 is active, the abnormality detection unit 1 of the CPU control unit 100
07 can be determined to be active. Next, the reset factor read from the status information reading unit 209 is stored in the work RAM 203 (S11), and the interrupt processing is completed. At this time, the delay circuit 401 is set in the reset circuit unit 205b so that the reset signal 211 of the data link control unit 200 does not become active until the interrupt processing is completed.
The data is reliably stored in the work RAM 203.

Next, the data link control unit 200 is reset by the reset signal 211 of the data link control unit 200, and transmits an abnormal signal to the M master station 30. That is, the above-mentioned reset state means that data transmission / reception via the data link I / F unit 204 is interrupted, and consequently, to the M master station 30, for example, the fact that the L1 local station 35 is abnormal is transmitted. Become.
This down state is reported to the maintainer by some means, and a reset factor request signal (not shown) is transmitted from the M master station 30.

At this time, since the reset signal 211 of the data link control unit 200 is a one-shot pulse, the reset is released from the data link control unit 200 of the L1 local station 35, and the data link I / F unit 204 receives the signal. It is possible. Therefore, the CPU 201 that has decoded the reset factor request signal
3, the reset factor (in this case, the WDT signal 117)
And a reset cause is transmitted from the data link I / F unit 204. The M master station 30 that has requested the reset factor obtains the reset factor (WDT signal 117) by the same receiving method as the normal data.
The maintainer will know that the abnormality detection unit 107 of the L1 local station 35 has been activated.

With the above-described configuration, in the central control room in the office or the like, the abnormality of the programmable controller left in another factory can be easily determined, and the time required to return to the normal state can be reduced. Can be expected.

[Embodiment 4] In the above embodiment, I
Although the operation has been described using the NT signal 210 as an interrupt signal of the CPU 201, as another embodiment, the NT signal 210 is input to the status information reading unit 209 instead of the interrupt signal of the CPU 201,
A similar effect can be expected from a hardware latch signal (storage trigger by flip-flop). In this case, the only difference is whether the data is stored in the work RAM 203 by software or stored in a flip-flop by hardware at the reset factor storing stage (in this embodiment, the status information reading unit 209 is connected to the flip-flop). Etc.).

[Embodiment 5] FIG. 6 is a block diagram showing a schematic configuration (embodiment 5) of a programmable controller according to the present invention. This embodiment relates to an improvement of the programmable controller shown in FIG. That is, in the system shown in FIG. 3, for example, when the power of the L1 local station 35 goes down due to a power failure or the like, the data link I / F unit 204 does not operate at all, and it is not possible to detect the cause of the abnormality. Have difficulty. Further, the data link system shown in FIG. 15 goes down. This embodiment solves this problem, and the power supply switching circuit 2
12 and the power supply switching circuit 212
To work.

That is, the power supply unit 10 generates a DC voltage 13 (usually 5 V DC) from the AC power supply (not shown) by the constant voltage circuit 11, and this generates a driving power supply for the CPU control unit 100 and the data link control unit 200. Becomes Further, the abnormality detection circuit 12 detects the value of the DC voltage and, for example,
If the voltage drops to 80% or less, it is considered that the power is off, and the power-off signal 1
5 is set to be active. For example, the abnormality detection signal 14 which operates as a reset signal when it becomes 70% or less is set to be active.

The power-off signal 15 is supplied to the power-supply switching circuit 21
2, when this signal becomes active (power failure), the power supply switching circuit 212 causes the data link I / F
The unit 204 or the entire data link control unit 200 is configured to switch to a backup power source of a battery (not shown).

Next, the operation will be described. When the AC power supply (not shown) is normal, the power-off signal 15 is in an inactive state, and the power supply switching circuit 212 supplies the DC voltage 13 generated by the AC power supply. Next, when the AC power is interrupted, the power cutoff signal 15 becomes active, and the power supply switching circuit 212 supplies a backup voltage such as a battery. At this time, the power supply switching circuit 21
2 is connected to the data link I / F unit 204 (not shown). That is, when the AC power supply is interrupted, only the data link I / F unit 204 is in an operable state, so data is received from the M master station 30 and the received data is transmitted to the L2 local station 40.

Therefore, in the conventional system, in the data link system shown in FIG.
For example, when the L1 local station 35 stops due to a power outage, the data link system itself is down. According to the present embodiment, the operation of the data link system shown in FIG. Adverse effects are minimized.

Embodiment 6 Embodiment 6 will be described with reference to FIG. With the battery backup of the data link I / F unit 204, it is possible to prevent the entire data link system shown in FIG. 17 from going down. However, the station (for example, L
The information of one local station 35) cannot be obtained by the M master station 30. In the present embodiment, in order to solve this problem, the CPU 201 of the data link control unit 200 includes:
The ROM 202, the work RAM 203, and the data link I / F unit 204 are backed up by a battery.

Next, the operation will be described. When the AC power of the L1 local station 35 is cut off, the power-off signal 1
5 is output from the abnormality detection circuit 12 and the power-off switching circuit 2
12 is in the battery backup mode. That is, before the power failure, the CPU 201 and the ROM 202
, The RAM 203, and the data link I / F unit 204 are operated by the DC voltage 13 generated from the AC power supply, but are driven by a backup voltage (not shown) such as a battery during a power failure. You. At this time, since the CPU 201, the ROM 202, and the RAM 203 are configured to be in the low power consumption mode (standby mode), it is considered that the battery consumption is minimized (the CPU and the like are operated with low power consumption). Various methods for setting the mode, such as lowering the operating clock of the CPU, are known, and description thereof is omitted here.)

The data link I / F section 204 is always operable by the backup voltage, and the data link system shown in FIG. 17 does not go down for the same reason as described above. Omitted. Next, when a request such as a reset factor request signal is transmitted from the M master station 30, the L1 local station 35 performs the following operation on the assumption that the specific data has been received. That is, the data link I / F unit 204 determines the specific data by hardware, and a specific data determination signal (not shown) determined as the specific data is transmitted to the CPU 201 and the RO.
The M202 and the RAM 203 are brought into a normal operable state from the standby mode.

When the specific data discrimination signal becomes active and enters a normal operation state, the same operation as that shown in FIG. 3 is performed, and a detailed description is omitted. However, in the case shown in FIG. 3, the reset operation due to the power failure cannot be detected, but in this embodiment, the reset operation at the time of the power failure can also be detected as a factor. The operation will be described below.

When the AC power supply of the L1 local station 35 is out of power, the abnormality detection signal 14 becomes active after the power cutoff signal 15 becomes active as described above. The abnormality detection signal 14 is sent to the reset circuit unit 10 of the CPU control unit 100 via the OR element 111 and the OR element 113.
8 to make the CPU 101 in a reset state (to eliminate unstable operation due to a drop in DC voltage), and at the same time, the I / O reset signal 114 becomes active via the OR element 110, and the I / O unit 300 is reset. State. At the same time, since the I / O reset signal 114 is input to the reset circuit unit 205b of the data link control unit 200, the INT signal 210 becomes active.

CPU 201, ROM 202, RAM
Since the standby mode 203 is set in the standby mode after a predetermined time, the normal operation is possible when the INT signal 210 becomes active, so that the interrupt process described with reference to FIG. Complete. That is, the reset factor (in this case, a power failure or a momentary power failure) is stored in the RAM 203. Thereafter, the data link control unit 200 is reset by the reset signal 211 and enters the standby mode. Hereinafter, the operation described above is performed. Further, it is also possible to change from the normal operation state to the standby state by making the specific data link determination signal inactive.

[Embodiment 7] FIG. 7 is a block diagram showing a schematic configuration (embodiment 7) of a programmable controller according to the present invention. In the distributed control system as shown in FIG. 15, the M master station 30 and the L1 local station 35
Normally, the power supply is operated by a separate power supply. Conventionally, for example, there is no power supply restriction in the distributed control system such as starting up the M master station 30 and then starting up the L1 local station 35 which is a local station. there were.

In this embodiment, in order to solve the above problem, a synchronous start permission flag section 260, a system starting means 262, and a system stop permission means 264 are provided. The basic operation of the programmable controller shown in FIG. 7 has already been described, and will not be described here.

First, the synchronization start permission flag section 260 shown in FIG. 7 will be described. The synchronous start permission flag section 260 is an E ² PROM or a flash ROM.
Since the power is stored by a battery or the like, it is assumed that the state is stored even at the time of power failure. And
When the synchronization start permission flag is, for example, "1", the distributed control system shown in FIG. 15 starts the operation of each programmable controller in synchronization, and for example, "0".
At this time, each programmable controller is configured to operate asynchronously.

Next, the operation will be described with reference to FIG. When the power is turned on, the CP of the CPU control unit 100
U101 checks the state of the synchronization start permission flag.
That is, the CPU 101 outputs a synchronous start permission flag read request to the CPU 201 of the data link control unit 200 via the two-port RAM 207. The CPU 201 reads out the synchronization start permission flag stored in the synchronization start permission flag section 260 and transfers it via the two-port RAM 207.

If the received information is “1”, the CPU 1
01 outputs the synchronous start permission flag read request again without executing the sequence processing, and executes the same operation.
A state of waiting for synchronization with another station is entered (S12). When the received information changes to "0", output refresh processing (S13), input refresh processing (S14), arithmetic processing (S15), END processing (S16), and data link processing (S17) are executed, respectively. A sequence process similar to that of the related art is started (see A in FIG. 13).

When the distributed control system is operating, the synchronization start permission flag is normally in the "0" state. Therefore, for example, when the power supply of the L1 local station 35 returns from the disconnected state due to a momentary power failure or the like, the CPU 101 executes the operation shown in FIG. However, at this time, since the synchronization start permission flag is “0”, the sequence processing is immediately executed without entering the “synchronization waiting” state. Also,
The termination of the sequence processing is performed irrespective of the synchronization start permission flag. For example, the sequence processing ends when the power of the L1 local station 35 is turned off (see the part B in FIG. 13).

Next, the operation of changing the synchronization start permission flag from "1" to "0" will be described. For example, the programmable controller of the M master station 30 has a system start-up means 262, and it is possible to set the necessity of the synchronous start of the distributed control system shown in FIG. 15 (in this case, the M master station 30 Start-up designated station programmable controller). That is, the M master station 30
Is turned on, the data link control unit 200 of the M master station 30 becomes operable, and the CPU 201
The processing operation shown in FIG. 9 is executed. That is, it is determined whether the system activation unit 262 is ON / OFF (S18). If the system activation unit 262 is set to require synchronization start, it is determined that the system activation unit 262 is in the ON state, and the process of the next step is executed.

Next, another station (for example, L1 local station 35)
(S1) operation (standby) status is checked (S1).
9). That is, for example, when the power of the L1 local station 35 is still in the OFF state, the distributed control system illustrated in FIG. 15 enters a standby state instead of a standby state and continuously monitors another station.

Next, when the power of the L1 local station 35 is turned on and the distributed control system is in the standby state, the processing of the next step is executed. That is, a system start command is transmitted from the M master station 30 to another station (S2).
0), after the transmission process is completed, “0” is set in the synchronization start permission flag section 260 of the own station (M master station 30) (S).
21). Hereinafter, the processing operation after step S12 shown in FIG.
0 starts the sequence processing.

Next, the operation of another station (for example, L1 local station 35) that has received the system start command transmitted from the M master station 30 will be described. L1 local station 35
When the power is turned on, the data link I / F unit 204 of the data link control unit 200 can transmit and receive.
The other station (for example, M
Inform the master station 30).

Next, the system is in a state of waiting for reception of a system start command, and determines whether a system start command has been received as shown in FIG. 10 (S22). As a result, when the system start command is received, the process of the next step is executed. That is, similarly to the M master station 30, "0" is set to the synchronization start permission flag section 260 of another station (for example, the L1 local station 35) (S23). Hereinafter, the M master station 30
And the sequence processing of the L1 local station 35 is started.

Next, the operation of the distributed control system shown in FIG. 15 for stopping the system will be described. The system stop permission means 264 shown in FIG. 7 is constituted by, for example, a key switch (not shown).
A case in which the maintainer stops the system using the programmable controller of the L1 local station 35 will be described.

When the maintenance person turns on the key switch, the system stop permission means 264 becomes active. The CPU 201 of the data link control unit 200 detects the state and determines the ON / OFF state (S24). ON
If it is determined to be in the state, the operation of the next step is executed. That is, the other station (in this case, the M master station 30, L2
The operation status of the local station 40 and the L3 local station 45 is checked (S25), and if it is determined that the other station is operating normally, a system stop permission command is transmitted from the L1 local station 35 to the other station (S26). . Next, after the transmission of the system stop permission command is completed, the synchronization start permission flag of the own station (in this case, the L1 local station 35) is set to “1” and the synchronization start permission flag unit 260 is reset (S27). ). This state corresponds to the portion D in FIG. If it is determined in step S25 that the other station is operating abnormally, error processing is executed (S2).
8).

Since a series of these operations are performed instantaneously, the maintainer turns on the key switch and then turns off the power of the L1 local station 35, so that the L1 local station 35 in the state of part B in FIG. Is interrupted, and it can be brought into a stopped state (the synchronous start permission flag is in the state of "1").

Next, the operation of the other station will be described. Since the basic operations are all the same, for example, the L2 local station 4
0 will be described. The system stop permission signal transmitted from the L1 local station 35 is transmitted to the data link I / F unit 2
04, and is received by the L2 local station 40. It is determined whether the received data is a system stop permission signal (S2).
9) If the received data is determined to be a system stop permission signal, the synchronous start permission flag is set to "1" and reset processing is executed (S30).

That is, similarly to the L1 local station 35,
Synchronization start permission flag section 260 of L2 local station 40
Is in a reset state, and is in a state of a portion D in FIG.
Thereafter, by turning off the power, the L2 local station 40 can be brought into the state of section B in FIG. Here, L2
The local station 40 receives the system stop permission signal and executes the above-described processing (steps S29 and S30), and at the same time, the data link I / F unit 204 transmits the system stop permission signal to the next station (in this case, the L3 local station 45). ), The L3 local station 45 operates at the same time. That is, each of the programmable controllers constructing the distributed system shown in FIG. 15 can be stopped in the state of part B in FIG.

Here, even when the power of the programmable controller is turned off, the synchronous start permission flag section 260 is stored and held in the flash ROM or the like. Therefore, when the power is turned on again to start up the system, FIG. The same operation as that of the section A is repeated also in the section E of FIG. 13, and as a result, each programmable controller of the system can start in synchronization.

Next, application examples of the above embodiments will be described.
First, the reset signal generation circuit 206
1 has been described as being activated by software (see FIG. 1).
Decodes the specific data (reset command) received by the data link I / F unit 204 by hardware, and
The same effect can be obtained even if the configuration is such that the local station reset signal 116 is directly output without passing through the PU 201.

Secondly, the description has been made by connecting only the reset factor as the input signal of the status information reading unit 209.
The same effect can be obtained even if other abnormal information or normal information is added as an input signal.

Third, the INT signal 210 is sent to the CPU 20
The operation applied as an interrupt signal of 1 has been described.
The same effect can be obtained by using the T signal 210 as a latch signal of the status information reading unit 209.

Fourth, the same effect can be obtained by reversing "1" and "0" in the synchronous start permission flag.

Fifth, the distributed control system has been described with the loop connection. However, the same effect can be obtained even if the distributed control system is connected by a bus connection or the like.

Sixth, the system stop permission means 264
Although the description has been given with the key switch, a similar effect can be obtained by a hardware configuration in which the switch is turned on after a certain period of time after the synchronization is started. Has the same effect.

[0093]

As described above, in the programmable controller according to the present invention and the distributed control system using the same, a method of resetting a specific other station, a method of detecting a reset factor of another station, a method of monitoring an abnormal station, a method of synchronously starting and a method of synchronizing stop. According to the method, first, in a centralized control room in an office or the like, a programmable controller installed in another factory or a distant place can be returned to normal. Second, the reset factor (abnormal factor) of the abnormal programmable controller can be transmitted to the normal programmable controller (for example, the M master station). Third
Furthermore, even if the abnormal programmable controller is in a power-off state such as a power failure, the cause can be detected (transmitted). Fourth, even if one programmable controller goes down,
Avoid downtime of the entire distributed control system. Fifth, it enables a synchronous start of the distributed control system.

To summarize the above effects, it is possible to perform a recovery work without going to the place where the local station which is down due to the abnormality is installed, to improve the work efficiency, and to use a plurality of distributed stations with separate power supplies. Even if it starts up, the distributed system is started normally, and further, in the distributed control system in which the loop is continued, it is possible to prevent the entire system from going down due to the fact that one station becomes an abnormal station, thereby improving the operating efficiency of the system. Can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration (Example 1) of a programmable controller according to the present invention.

FIG. 2 is a block diagram showing a schematic configuration (Example 2) of a programmable controller according to the present invention.

FIG. 3 is a block diagram showing a schematic configuration (Example 3) of a programmable controller according to the present invention.

FIG. 4 is a block diagram showing a schematic configuration of a reset circuit section of the programmable controller according to the present invention.

FIG. 5 is a flowchart showing an operation of an INT process.

FIG. 6 is a block diagram showing a schematic configuration (Embodiment 5) of a programmable controller according to the present invention.

FIG. 7 is a block diagram showing a schematic configuration (Embodiment 7) of a programmable controller according to the present invention.

8 is a flowchart showing an operation of the programmable controller shown in FIG.

FIG. 9 is a flowchart showing an operation of the programmable controller shown in FIG. 7;

FIG. 10 is a flowchart showing an operation of the programmable controller shown in FIG. 7;

11 is a flowchart showing an operation of the programmable controller shown in FIG.

FIG. 12 is a flowchart showing an operation of the programmable controller shown in FIG. 7;

FIG. 13 is a timing chart showing the timing of each section of the programmable controller according to the present invention.

FIG. 14 is a block diagram showing a schematic configuration of a conventional programmable controller.

FIG. 15 is an explanatory diagram schematically showing a distributed control system.

16 is a flowchart showing an operation of the programmable controller shown in FIG.

17 is a flowchart showing a data link process of the programmable controller shown in FIG.

FIG. 18 is a flowchart showing an operation of the programmable controller shown in FIG.

FIG. 19 is a flowchart showing an operation of the programmable controller shown in FIG.

[Explanation of symbols]

 Reference Signs List 10 power supply unit 11 constant voltage circuit 12 abnormality detection circuit 100 CPU control unit 106 reset switch 107 abnormality detection unit 108 reset circuit unit 200 data link control unit 202 ROM 203 work RAM 204 data link I / F unit 205, 205a, 205b reset circuit Unit 206 Reset signal generation circuit 209 Status information reading unit 212 Power supply switching circuit 260 Synchronous start permission flag unit 262 System start unit 264 System stop permission unit 300 I / O unit unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G05B 19/04-19/05

Claims (11)

(57) [Claims] 1. A power supply unit, CPU control unit, the data link control unit, in a programmable controller configured with I / O controller, before Symbol power unit anomaly detection detects an abnormality of the power source, and outputs a power reset signal and means, prior SL CPU control means includes a reset switch means for outputting a forced reset signal for forcibly resetting the device, before Symbol data link control means data link interface to communicate with another station, the CPU control reset signal generating means for resetting the means and I / O control means includes a reset means for resetting the data link control unit, resetting means before Symbol data link control means is output from the abnormality detecting means of the power supply unit Power reset signal and forced reset output from reset switch means of the CPU control means. And outputting a reset signal based on the reset signal. 2. The programmable controller according to claim 1,
There the rollers to a distributed control system for performing multiple connection to distributed control, to specify the other Tsubonepu Roguramabu <br/> Le controllers that require a reset, data transmission reset command of the other Tsubonepu log llama logic controllers The other station receives the reset command, generates a reset signal based on the reset command, and uses the reset signal to control at least CPU control means of the other station and I / O control. A method for resetting a specific other station in a distributed control system, characterized by resetting means. 3. A power supply unit, CPU control unit, the data link control unit, in a programmable controller configured with I / O controller, before Symbol power unit anomaly detection detects an abnormality of the power source, and outputs a power reset signal and means, prior SL CPU control unit includes a forced reset signal is forcibly reset the device, the reset switch means for outputting an abnormality reset signal output by the abnormality such as operation astringent band, before serial data link control means data link interface to communicate with other stations, has a resetting means for resetting the data link control unit, resetting means before Symbol data link control means, the I /
A programmable controller which is controlled based on an I / O reset signal for resetting an O control means and outputs a reset signal. 4. A power supply unit, CPU control unit, the data link control unit, in a programmable controller configured with I / O controller, before Symbol power unit anomaly detection detects an abnormality of the power source, and outputs a power reset signal and means, prior SL CPU control unit includes a forced reset signal is forcibly reset the device, the reset switch means for outputting an abnormality reset signal output by the abnormality such as operation astringent band, before The data link control means is a data link interface for communicating with another station, a reset signal generating means for resetting the CPU control means and the I / O control means, a reset means for resetting the data link control means, and the reset means section is active. Reset factor status information storage means for storing the factor to be set, and the reset factor status Has a reading means for reading the reset factor from the information storing means, resetting means before Symbol Data Link Control means, the I /
A programmable controller, which receives an I / O reset signal for resetting the O control means, and outputs an interrupt signal to the control means and a reset signal. 5. A distributed control system for executing distributed control by connecting a plurality of programmable controllers,
The reset signal generated by such anomalies in other Tsubonepu log llama logic controllers, the other by the reset signal
Tsubonepu resets at least CPU control unit and I / O control unit of the log llama Bull the controller to generate an interrupt signal to the data link control means in said other Tsubonepu log llamas logic controllers by the reset signal, the interrupt signal by storing the cause of the reset signal to the other Tsubonepu log Lama Bull the controller, the reset factor to the data link control means for a predetermined time reset after storage, the abnormal by the data link interface via in said other station programmable controller It transmits a signal at the own Tsubonepu log Lama logic controllers other than the other stations, to receive different <br/> normal signal of the other station, after the abnormality signal receiving, the other Tsubonepu log <br/> Lama A reset factor request signal for requesting a reset factor in the The other Tsubonepu receives the reset factor demand signal at log Lama Bull the controller sends a reset factor are stored, receives the reset factor in the data link interface via in said self Tsubonepu log llama logic controllers A method for detecting a reset factor of another station in a distributed control system. 6. A power supply unit, CPU control unit, the data link control unit, in a programmable controller configured with I / O controller, before Symbol power unit anomaly detection detects an abnormality of the power source, and outputs a power off signal and means, before Symbol data link control means comprises a data link interface to communicate with another station, the reset signal generating means for resetting the CPU control unit and I / O control unit, a power supply switching means for switching to backup power supply , power switching means before Symbol data link control means, at the same time is switched to the backup power supply from the power supplied from the power supply unit by power-off signal from the abnormality detecting means of the power supply unit, said by the power-off signal Operate at least the data link interface in the data link control means by the backup power supply A programmable controller characterized by enabling. 7. A power supply unit, CPU control unit, the data link control unit, in a programmable controller configured with I / O controller, before Symbol power unit anomaly detection detects an abnormality of the power source, and outputs a power off signal and means, before Symbol data link control means, data link interface having a specific data detection means for detecting the reception of the specific data to communicate with other stations, a reset signal for resetting the CPU control unit and I / O control unit generating means, resetting means for resetting the data link control unit, the reset source status information storage means for storing the factors that said reset means active, the reset factor status information storage means reading hand <br/> for reading reset factor from Power switching means to switch to backup power supply, all data link control means Control means for controlling a storage means in which a program for the control unit executes the control process is stored, a storage means for storing the results was performed and the data by the control unit, before Symbol Data Link Control The power switching means of the means is switched from the power supplied from the power supply section to the backup power supply by a power supply cutoff signal from the abnormality detection means of the power supply section, and at the same time, the data link control means At least the control means, the storage means, the storage means in the standby state by the backup power supply,
And operable at least data link interface in the data link control unit, the data link interface, by the specific data detection unit that will receive specific data, at least the control means, storage means, the standby storage means A programmable controller characterized by changing from a state to an operating state. 8. In the distributed control system by connecting a plurality of programmable controllers perform distributed control,
A data link for detecting power interruption of an AC power supply, switching between a power supply supplied from the AC power supply and a backup voltage according to the detected power supply interruption signal, and communicating with another station programmable controller by the backup voltage switched by the switching. Control means for controlling at least the entire data link control means of the data link control means at the same time as enabling the interface; storage means for storing a program for executing the control processing by the control means; executed by the control means The storage means for storing the results and data obtained in the standby state, receiving specific data from the other station programmable controller,
A method of monitoring an abnormal station in a distributed control system, wherein at least the control unit, the storage unit, and the storage unit in the data link control unit are made operable from a standby state by the backup voltage by receiving the specific data. 9. The power supply unit, CPU control unit, the data link control unit, in a programmable controller configured with I / O controller, before Symbol data link control means for starting synchronously with other stations programmable controller a synchronization start permission flag of, by comprising a system activation means for activating the distributed control system configured by a programmable controller of multiple, and a system stop permitting means for providing a system stop permission command before Symbol distributed control Shitesumu A programmable controller. There the distributed control system for executing the distributed control 10. by connecting a plurality of programmable controllers
The sequence processing is started by the synchronization start permission flag, and after the synchronization start permission flag is permitted, the synchronization start processing of the programmable controller that executes a predetermined sequence processing and the synchronization start of the distributed control system are started. Monitoring the standby state of the other station programmable controller, and after the other station programmable controller is in standby,
A system start command is transmitted, the system start processing of the system start command station programmable controller in the distributed control system in which the synchronous start permission flag of the own station is set to the enable state, and the system start command is received from the system start designated station programmable controller. A system start-up method in a distributed control system in which a synchronous start permission flag of its own station is set to a permission state. A 11. A distributed control system by connecting a plurality of programmable controllers perform distributed control
Te, allow the system stop, the other station programmable controller determines whether or not the normal operation, when the other station programmable controller is in normal operation, sends a system stop permission command, synchronous start permission flag of the local station To a non-permitted state, and after setting the synchronous start permission flag to a non-permitted state, turning off the power of the own station to stop the system of the designated station programmable controller, and receiving the system stop permission command from the designated station programmable controller. Then, after receiving the system stop permission command, the synchronous start permission flag of the own station is set to the non-permitted state, and after the synchronous start permission flag is set to the non-permitted state, the power supply of the own station is turned off. In a decentralized control system characterized by executing a stop process Period stopping method.