JP7796633B2 - Plant monitoring and control system - Google Patents

Description

This application relates to a plant monitoring and control system.

Conventional plant monitoring and control systems use PLC (Programmable Logic Controller) devices to monitor and control logging data obtained from plant equipment, achieving factory automation (FA).

In such cases, prior art has proposed a technique for achieving data logging using a PLC device by providing the PLC device with a dedicated logging data transmission device, such as a data logger unit, and transmitting the logging data to an external storage device at the PLC device's control cycle (see, for example, Patent Document 1 below).

Patent No. 6160781

However, with the prior art described in Patent Document 1, transmitting logging data at control cycles is not achieved based on a program executed by the PLC device, but rather requires the PLC device to be equipped with a dedicated logging data transmission device, which increases system costs.

This application has been made to solve the above-mentioned problems, and aims to provide a plant monitoring and control system that reduces system costs by enabling logging data to be transmitted to an external storage device at control cycles without the need to install a dedicated logging data transmission device in the PLC device.

The plant monitoring and control system disclosed in the present application includes a PLC device for plant control and an engineering tool device for logging setting and monitoring, the engineering tool device including a logging setting function unit that sets logging conditions for acquiring logging data for the PLC device , a program generation function unit that generates a data transmission program that conforms to the logging conditions and transmits the program to the PLC device, an external storage device that stores the logging data transmitted from the PLC device based on the logging conditions, and a logging monitoring function unit that monitors the logging data stored in the external storage device, the PLC device transmitting the logging data to the external storage device at intervals based on a control period based on the data transmission program , the external storage device sequentially storing the logging data, and the logging monitoring function unit monitoring the logging data stored in the external storage device.

The plant monitoring and control system disclosed in this application eliminates the need to install a dedicated logging data transmission device in the PLC device, thereby reducing system costs.

1 is a functional block diagram showing a configuration of a plant monitoring and control system according to a first embodiment. 2 is a diagram illustrating details of a logging setting function unit and a logging monitoring function unit in FIG. 1. FIG. 4 is a flowchart showing a logging setting operation according to the first embodiment. 4 is a flowchart showing a logging monitoring operation according to the first embodiment; FIG. 10 is a functional block diagram showing the configuration of a plant monitoring and control system according to a second embodiment. 6 is a diagram illustrating details of a logging setting function unit and a logging monitoring function unit in FIG. 5. FIG. FIG. 10 is an explanatory diagram showing a transmission data format of logging data according to the second embodiment. FIG. 10 is an explanatory diagram showing an example of a data transmission program for logging data according to the second embodiment; FIG. 11 is a functional block diagram showing the configuration of a plant monitoring and control system according to a third embodiment. 10 is a diagram illustrating details of a logging setting function unit and a logging monitoring function unit in FIG. 9. FIG. FIG. 10 is a functional block diagram showing the configuration of a plant monitoring and control system according to a fourth embodiment. 12 is a diagram illustrating details of a logging setting function unit and a logging monitoring function unit in FIG. 11. FIG. FIG. 10 is an explanatory diagram showing a transmission data format of logging data according to the fourth embodiment. FIG. 10 is an explanatory diagram showing an example of a data transmission program for logging data according to the fourth embodiment; FIG. 10 is an explanatory diagram showing the relationship between the control period, collected logging data, and data transmission timing of the PLC device according to the fourth embodiment. FIG. 10 is a functional block diagram showing the configuration of a plant monitoring and control system according to a fifth embodiment. 17 is a diagram illustrating details of a logging setting function unit and a logging monitoring function unit in FIG. 16. FIG. FIG. 13 is an explanatory diagram showing a transmission data format of logging data according to the fifth embodiment. FIG. 13 is an explanatory diagram showing an example of a data transmission program for logging data according to the fifth embodiment. FIG. 10 is an explanatory diagram showing the relationship between each control period, collected data, storage destination, and data transmission timing of a PLC according to a fifth embodiment.

Embodiment 1.
FIG. 1 is a functional block diagram showing the configuration of a plant monitoring and control system according to a first embodiment of the present invention, and FIG. 2 is a diagram showing details of a logging setting function unit and a logging monitoring function unit shown in FIG.

The plant monitoring and control system of this first embodiment includes a PLC device 1 that controls the plant, an input/output device 3 that is connected to the PLC device 1 and exchanges data for plant control, an engineering tool device 4 that performs engineering such as editing programs to be written to the PLC device 1, setting logging, and monitoring, and a LAN network 8 that provides communication between the PLC device 1 and the engineering tool device 4.

The PLC device 1 has a CPU unit 2, which is composed of a program execution unit 21 that performs calculations such as programs for plant control, a communication processing unit 22 that communicates with external communication devices via the LAN network 8, an input/output processing unit 23 that performs input and output processing of analog/digital signal data between the input/output device 3, and a device memory 24 that stores data such as input signals and output signals from the input/output processing unit 23 as a result of program calculations.

The input/output device 3 is connected to various devices that make up the plant, such as sensors, valves, and actuators (not shown), and exchanges analog and digital signal data between the various devices and the PLC device 1.

The engineering tool device 4 has a logging control unit 5 that controls the transmission, storage, and monitoring of logging data to the PLC device 1, and an external storage device 7 that stores logging data obtained from the PLC device 1 based on logging conditions set by the logging setting function unit 51 described below.

The logging control unit 5 includes a logging setting function unit 51 that sets logging conditions for acquiring logging data for the PLC device 1, a PLC support unit 53 that serves as a program generation function unit that generates a data transmission program 6 to be executed by the PLC device 1 based on the information set by the logging setting function unit 51 and transfers it to the PLC device 1, and a logging monitoring function unit 52 that displays the logging data accumulated in the external storage device 7 on an operator's monitoring screen and monitors the logging data.

3 is a flowchart showing the logging setting operation according to this embodiment 1. In the following, the symbol S denotes a processing step.
When setting conditions for acquiring logging data from the PLC device 1 , the operator uses the logging setting function unit 51 of the engineering tool device 4 .

3, the operator activates the logging setting function unit 51 (step S0010), and in response, the logging setting function unit 51 displays on the screen information about the PLC device 1 for which logging settings are to be made (step S0020).
Next, the operator sets common items for logging settings (for example, maximum number of analog collection points, maximum number of digital collection points, and logging data storage period) on the screen of the logging setting function unit 51 (step S0030).
Also, labels (identification names for identifying the signals) are set for the analog and digital signals at the collection points where logging data is monitored (step S0040).
Based on the set label information, the logging setting function unit 51 automatically acquires the label name of the label registered as engineering data and the target device memory 24, and displays them on the screen (step S0050).
Then, the operator presses the save button on the screen of the logging setting function unit 51 to save the setting data (step S0060).

The PLC support unit 53 generates a data transmission program 6 based on the common setting items and collection target point setting items set by the logging setting function unit 51 (step S0070). This data transmission program 6 is a program that collects values from the device memory 24 of the PLC device 1 that is the target of the label set by the logging setting function unit 51 and transmits the data to the external storage device 7.

By pressing the transfer button on the logging setting function unit 51 screen (step S0080), the PLC support unit 53 transfers the data transmission program 6 to the CPU unit 2 of the PLC device 1 via the LAN network 8 (step S0090). After completing the operation, the operator terminates the operation of the logging setting function unit 51 (step S0100).

The PLC device 1 executes the transferred data transmission program 6 every control period (e.g., every 5 ms), and transmits the values in the device memory 24 to be collected from the communication processing unit 22 to the external storage device 7 via the LAN network 8.

FIG. 4 is a flowchart showing the logging monitoring operation according to the first embodiment.
When monitoring the logging data, the operator uses the logging monitoring function unit 52 of the engineering tool device 4 .

The operator activates the logging monitoring function unit 52 (step S1010). In response to this, the logging monitoring function unit 52 displays a monitoring screen based on the setting information of the logging setting function unit 51 (step S1020), references the logging data transmitted from the PLC device 1 and stored in the external storage device 7, and displays graphs and current values of each label on the screen (step S1030).
The logging monitoring function unit 52 waits for a fixed time (for example, every second), and periodically references the logging data to draw a graph on the screen and update and display the current values (step S1040), enabling real-time monitoring. After completing the operation, the operator terminates the operation of the logging monitoring function unit 52 (step S1050).

As described above, this first embodiment includes a logging setting function unit 51 that sets the conditions for acquiring logging data for the PLC device 1; a PLC support unit 53 that serves as a program generation function unit that generates a data transmission program 6 to be executed by the PLC device 1 based on the information set by the logging setting function unit 51 and transfers it to the PLC device 1; and a logging monitoring function unit 52 that displays logging data accumulated in the external storage device 7 from the CPU unit 2 of the PLC device 1 for each control cycle on an operator's monitoring screen and monitors the logging data. This eliminates the need to attach a dedicated logging data transmission device to the PLC device 1, as was previously required. This makes it possible to accumulate logging data in real time and monitor it historically without increasing system costs.

Embodiment 2.
In the above-described first embodiment, a case has been described in which a single PLC device 1 exists within a system, but depending on the plant monitoring and control system, a plurality of different models of PLC devices may coexist within the same system.

In this second embodiment, the data format of the logging data handled by the logging control unit 5 is standardized, and a data transmission program is generated for each PLC device. This allows the same effects as in the first embodiment to be achieved, regardless of the model of the PLC device, even when multiple different models of PLC devices are mixed within the same system.

FIG. 5 is a functional block diagram showing the configuration of a plant monitoring and control system according to the second embodiment, and FIG. 6 is a diagram showing details of the logging setting function unit and the logging monitoring function unit shown in FIG.
In this second embodiment, as an example, two PLC devices, 1A of company A and 1B of company B, exist in the same system, and the devices 1A and 1B are different models. That is, the PLC device 1A of company A has a CPU unit 2A and an input/output device 3A. The PLC device 1B of company B has a CPU unit 2B and an input/output device 3B. The PLC device 1A of company A and the PLC device 1B of company B are each connected to the engineering tool device 4 via the same LAN network 8.

In addition, the PLC support unit 53 provided in the logging control unit 5 of the engineering tool device 4 generates data transmission programs 6A and 6B for communicating with each model of PLC device 1 and generating transmission data having a transmission data format corresponding to the program format supported by each model of PLC device 1A and 1B.

Therefore, the PLC support unit 53, which functions as a program generation function, generates data transmission programs 6A and 6B specific to each model of PLC device 1A, 1B, such as data transmission program 6A for company A and data transmission program 6B for company B, and transfers these programs to each PLC device 1A, 1B, transmitting, storing, and monitoring the logging data.

Figure 7 is an explanatory diagram showing the transmission data format of logging data in this embodiment 2.

The transmission data format is composed of a magic number (identifier) to identify it as logging data, the transmission data length, a transmission counter (incremented by the PLC device each time it is transmitted), transmission time (transmission time of the PLC device), information about the sending PLC device (such as the model name (controller name) of Company A's PLC device 1A and Company B's PLC device 1B), maximum number of points to collect (digital/analog), and collected data (collected logging data), and uses a common transmission data format that is independent of the PLC device model.

Figure 8 is an explanatory diagram showing an example of a data transmission program for logging data according to this second embodiment. Note that this shows a program written in ladder programming language, which is generally supported by PLC devices.

The data transmission program is a program tailored to the model of each PLC device 1A, 1B, and is composed of a transmission data format header information generation unit P0010, a collected data generation unit P0020, and a data transmission unit P0050. For data where the number of points to be collected in the logging setting function unit 51 is less than the maximum number of points to be collected, the analog value is generated as NaN (Not a Number) and the digital value is generated as 0 (P0030 "Analog collected data (NaN) (x+1 to mth point)" and P0040 "Digital collected data (0) (y+1 to nth point)" in Figure 8).

Note that while the programming format in ladder language has been described, this is merely one example, and the programming language does not have to depend on ladder language. It is possible to support this by providing the PLC support unit 53 with the ability to generate programming languages supported by each PLC device, such as ST (Structured Text) language, C language, or languages unique to the PLC device manufacturer.

As described above, in this second embodiment, when multiple PLC devices 1A, 1B of different models are mixed within the same system, the PLC support unit 53 of the logging control unit 5 generates data transmission programs 6A, 6B appropriate for the models of the PLC devices 1A, 1B. This eliminates the need to prepare an engineering tool device 4 that performs logging settings and monitoring for each PLC device 1A, 1B, and enables the transmission, storage, and monitoring of logging data without incurring additional costs.

Embodiment 3.
In the above first and second embodiments, the case where logging data setting and monitoring are performed using a CPU unit built into a PLC device has been described, but some PLC devices do not have an Ethernet communication function built into the CPU unit, and therefore, in order to connect to a LAN network, there are models in which an Ethernet unit must be provided separately from the CPU unit. Note that Ethernet is a registered trademark.

In this third embodiment, the logging setting function unit 51 of the logging control unit 5 selects the connection method for the PLC device 1C and generates a data transmission program 6C that corresponds to the connection method, thereby achieving the same effects as those of the first and second embodiments.

Figure 9 is a functional block diagram showing the configuration of a plant monitoring and control system according to embodiment 3, and Figure 10 is a diagram showing details of the logging setting function unit and logging monitoring function unit shown in Figure 9.

In this third embodiment, an Ethernet unit 2D is provided in addition to the CPU unit 2C in the PLC device 1C. That is, for example, the PLC device 1C manufactured by Company C has a CPU unit 2C, an Ethernet unit 2D, and an input/output device 3C, and the Ethernet unit 2D is connected to the engineering tool device 4 via the LAN network 8.

The logging setting function unit 51 of the engineering tool device 4 is also provided with a connection method setting function unit 510 that sets the connection method, allowing the operator to select the connection method for the PLC device 1C. The PLC support unit 53, which serves as a program generation function unit, generates a program in which the data transmission unit (P0050 in Figure 8 described above) is modified in the data transmission program 6C according to the connection method of the Ethernet unit 2D set by the connection method setting function unit 510. This allows the logging control unit 5 to set and monitor logging data.

As described above, in this third embodiment, by generating a data transmission program 6C according to the connection method of the PLC device 1C, even in models that require a separate Ethernet unit 2D to be installed in relation to the CPU unit 2C of the PLC device 1C, it is possible to transmit, store, and monitor logging data using the separately installed Ethernet unit 2D.

Embodiment 4.
In the above first to third embodiments, the case where logging data is transmitted at each control cycle of the PLC device has been described, but generally, control cycles are short, such as 5 ms, used in plant control. Therefore, if many PLC devices exist in the same system, if all the PLC devices transmit logging data to the LAN network at each control cycle, the communication load on the LAN network may become chronically high.

In this fourth embodiment, the data transmission program 6 executed by the PLC device 1 collects data every control period, but the timing of transmitting logging data varies for each PLC device 1 (however, the period is an integer multiple of the control period), thereby distributing the communication load on the LAN network 8. Below, we will explain, using Figures 11 to 15, how to arbitrarily set the timing of transmitting logging data from the PLC device 1.

FIG. 11 is a block diagram showing the configuration of a plant monitoring and control system according to the fourth embodiment, and FIG. 12 is a diagram showing details of the logging setting function unit and the logging monitoring function unit shown in FIG.
In the plant monitoring and control system of this fourth embodiment, it is assumed that a large number of PLC devices (not shown) are connected to the LAN network 8, and each will be referred to as a PLC device 1 in the following description.

In this fourth embodiment, the logging setting function unit 51 includes a transmission timing setting function unit 511 that sets the timing for transmitting logging data.

The transmission timing of the logging data set by the transmission timing setting function unit 511 can be arbitrarily set at a period (= n·f) that is an integer multiple n (n = 1, 2, ...) of the control period f so that it differs for each PLC device 1. When the operator specifies the transmission timing of the logging data to the transmission timing setting function unit 511 from the logging setting screen, the PLC support unit 53 as a program generation function unit generates a data transmission program 6 that conforms to the transmission timing set by the transmission timing setting function unit 511.
The period (=n·f) where n is an integer multiple of the control period f (n=1, 2, . . . ) that determines the timing of transmitting logging data will be referred to as the transmission timing period hereinafter.

FIG. 13 shows an example of a transmission data format in this fourth embodiment.
The header information of the transmission data format includes an item for determining the number of accumulated pieces of logging data obtained per control cycle (hereinafter referred to as the accumulated number). Here, this accumulated number is set to the same value as the integer value n that determines the transmission timing cycle. Therefore, the device memory 24 of the PLC device 1 stores the accumulated number of pieces of collected data (collected logging data) for each control cycle. In addition, a collection counter is provided, and the count value is incremented each time the PLC device 1 collects data in the device memory 24 per control cycle. This allows the logging monitoring function unit 52 to recognize how many control cycles the accumulated transmission data has covered and where the most recent collected data is stored, thereby enabling monitoring of the logging data.

FIG. 14 is an explanatory diagram showing an example of the data transmission program 6 for logging data according to the fourth embodiment.
The PLC device 1 executes the data transmission program 6 for each control cycle. Meanwhile, the collected data generation unit P1020 sets a collection counter to collect logging data for each control cycle. In addition, the transmission timing calculation unit P1060 calculates the transmission timing accordingly, and when the transmission timing is established (the count value of the collection counter matches the accumulated number), the transmission data format header information generation unit P1010 and the data transmission unit P1050 are executed to transmit the logging data via the LAN network 8. In this case, as described above, the collection counter increments for each control cycle, and when the accumulated number set by the transmission timing setting function unit 511 of the logging setting function unit 51 matches the count value of the collection counter, the transmission timing condition is established.

Figure 15 is an explanatory diagram showing the relationship between the control period, collected data (collected logging data), and data transmission timing of the PLC device 1.

The PLC device 1 collects logging data every control period, while transmitting the logging data every transmission timing period. The collected data section of the transmission data format is in a ring buffer format, and when the transmission timing arrives, the logging data is once again cycled from the beginning of the collected data, storing it sequentially in the device memory 24.

For example, if the control period for a given PLC device 1 is 5 ms and the transmission timing period is 50 ms (10 times the control period), a program is executed every 5 ms of the control period to collect data, while logging data is sent to the external storage device 7 of the engineering tool device 4 every 50 ms of the transmission timing period.

As described above, in this fourth embodiment, when multiple PLC devices 1 exist within the same system, the transmission timing setting function unit 511 provided in the logging setting function unit 51 changes the transmission timing period of the logging data for each PLC device 1, and the PLC support unit 53, which serves as a program generation function unit, generates a data transmission program 6 that matches the transmission timing of the logging data changed by the transmission timing setting function unit 511. This distributes the communication load on the network, enabling smooth transmission, storage, and monitoring of logging data.

Embodiment 5.
In the above-described first to fourth embodiments, the PLC device transmits the latest logging data obtained at each control cycle or transmission timing cycle to the engineering tool device, but there is a risk that transmission of the logging data may be interrupted due to communication load on the LAN network or a temporary communication abnormality. If transmission of the logging data is interrupted, the data for that cycle is not acquired and is treated as missing, resulting in the problem that the logging data cannot be monitored.

In this fifth embodiment, a data format for storing logging data obtained in past control cycles is generated as the transmission data format for logging data, and data is transmitted using this format. This prevents data loss even in the event of a temporary communication abnormality on the network, and enables the accumulation and monitoring of logging data. Below, we will explain the case where PLC device 1 transmits logging data obtained in past control cycles using Figures 16 to 20.

FIG. 16 is a functional block diagram showing the configuration of a plant monitoring and control system according to this fifth embodiment, and FIG. 17 is a diagram showing details of the logging setting function unit and the logging monitoring function unit of FIG.
In this fifth embodiment, a past value count setting function unit 512 that sets the past value count is provided inside the logging setting function unit 51. The other configurations are basically the same as those of the above-described embodiments.

The past value count set by the past value count setting function unit 512 is a value that determines the maximum number of times that previously obtained logging data is to be transmitted from the PLC device 1 to the external storage device 7, going back in time. The operator can set the past value count as desired on the logging setting screen, and the PLC support unit 53, which serves as a program generation function unit, generates a data transmission program 6 in accordance with the setting of the past value count setting function unit 512.

Figure 18 shows the transmission data format for this embodiment. The header information of the transmission data format includes items for setting the number of past values and the storage destination, thereby creating a storage block in the device memory 24 of the PLC device 1 for collecting past logging data.

The number of storage blocks prepared is equal to the number of past values + 1 (1 indicates the most recent value), and the number of collected data items prepared is equal to the number of storage items x (number of past values + 1). For example, if the control period is 5 ms, the number of storage items is 5 (the transmission timing period is 25 ms, or 5 times the control period), and the number of past values is 2, the number of storage blocks will be 3, and the number of collected data items will be 15 (= 5 x 3).

The storage location also stores a value indicating the location where the most recently collected data is stored (a value indicating which storage block contains the most recently collected data).

This allows the logging monitoring function unit 52 to recognize whether the transmitted data includes past data, or whether the collected data is the most recent periodic data. If there is missing data that could not be collected due to a temporary communication error, the logging monitoring function unit 52 will reference the past data from the collected data and fill in the missing data the next time it receives transmitted data from the PLC device 1.

FIG. 19 shows an example of the data transmission program 6 in this embodiment.
The PLC device 1 executes the data transmission program 6 for each control cycle, and the collected data generation unit P2020 sets a collection counter to collect logging data for each control cycle. In addition, the transmission timing calculation unit P2060 calculates the transmission timing accordingly, and when the transmission timing is established, the transmission data format header information generation unit P2010 sets the number of past values and the storage destination, executes the data transmission unit P2050, and transmits data via the LAN network 8.

FIG. 20 shows the relationship between each control period of the PLC device 1, collected data, storage destination, and data transmission timing.
The PLC device 1 collects logging data for each control cycle, updates the storage location indicating the location where the latest data is stored, and transmits the data at the transmission timing.

Collected data is stored in a ring buffer format, and when the number of accumulated data reaches "accumulation count x number of accumulated blocks (number of past values + 1)", the logging data is cycled from the beginning of the collected data to be stored sequentially in the device memory 24.

For example, if the control period is 5 ms, the transmission timing period is 25 ms (5 times the control period), and the number of past values is 2, the PLC device 1 will execute the program every 5 ms of the control period to collect data for each period, update the storage block where the data is stored every 5 periods, and store a total of 15 periods' worth of logging data.

As described above, in this fifth embodiment, the timing for transmitting previously obtained logging data can be set arbitrarily, and a data transmission program 6 is generated according to the setting and transmitted to the PLC device 1. The PLC device 1 then transmits previously obtained logging data accordingly, preventing data loss even in the event of a temporary communication abnormality on the network, and enabling the transmission, storage, and monitoring of logging data.

While various exemplary embodiments are described in this application, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations.

Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in this application. For example, this includes cases in which at least one component is modified, added, or omitted, or even cases in which at least one component is extracted and combined with components of another embodiment.

The various aspects of this disclosure are summarized below as appendices.

(Appendix 1)
The system is equipped with a PLC device for plant control and an engineering tool device for logging settings and monitoring,
The engineering tool device includes:
a logging setting function unit that sets logging conditions for acquiring logging data for the PLC device;
a program generation function unit that generates a data transmission program that conforms to the logging conditions set by the logging setting function unit and transmits the program to the PLC device;
an external storage device that stores the logging data transmitted from the PLC device based on the logging conditions set by the logging setting function unit;
a logging monitoring function unit that monitors the logging data stored in the external storage device;
Including,
The PLC device
transmitting the logging data to the external storage device for each control period based on the data transmission program;
the external storage device sequentially accumulates the logging data transmitted from the PLC device at control cycles;
the logging monitoring function unit monitors the logging data stored in the external storage device.
Plant monitoring and control system.
(Appendix 2)
A plant monitoring and control system as described in Appendix 1, wherein, when multiple models of PLC devices exist in the same system, the program generation function unit generates a data transmission program according to the model of each of the PLC devices.
(Appendix 3)
3. A plant monitoring and control system as described in claim 1 or 2, wherein the PLC device is provided with a separate Ethernet unit, the logging setting function unit is provided with a connection method setting function unit that sets a connection method, and the program generation function unit generates a data transmission program according to the connection method of the Ethernet unit that is set by the connection method setting function unit.
(Appendix 4)
A plant monitoring and control system as described in any one of Supplementary Note 1 to Supplementary Note 3, wherein, when a plurality of PLC devices exist in the same system, the logging setting function unit is provided with a transmission timing setting function unit that sets the transmission timing of logging data for each of the PLC devices, and the program generation function unit generates the data transmission program that is compatible with the transmission timing set by the transmission timing setting function unit.
(Appendix 5)
5. A plant monitoring and control system according to any one of claims 1 to 4, wherein the logging setting function unit is provided with a past value count setting function unit that sets a transmission timing for logging data obtained in the past, a data transmission program is generated in accordance with the transmission timing set by the past value count setting function unit, and the PLC device transmits the logging data obtained in the past based on the data transmission program.

1, 1A, 1B PLC device, 2, 2A, 2B, 2C CPU unit,
21 program execution unit, 22 communication processing unit, 23 input/output processing unit,
24 Device memory, 2D Ethernet unit,
3, 3A, 3B, 3C Input/output device, 4 Engineering tool device,
5 Logging control unit, 51 Logging setting function unit, 510 Connection method setting function unit,
511 Transmission timing setting function unit, 512 Past value count setting function unit,
52 logging monitoring function unit, 53 PLC support unit (program generation function unit),
7 external storage device, 6, 6A, 6B, 6C data transmission program,
8 LAN network.

Claims (5)

The system is equipped with a PLC device for plant control and an engineering tool device for logging settings and monitoring,
The engineering tool device includes:
a logging setting function unit that sets logging conditions for acquiring logging data for the PLC device;
a program generation function unit that generates a data transmission program that conforms to the logging conditions and transmits the program to the PLC device;
an external storage device that stores the logging data transmitted from the PLC device based on the logging conditions;
a logging monitoring function unit that monitors the logging data stored in the external storage device;
Including,
The PLC device transmits the logging data to the external storage device at each cycle based on the control cycle based on the data transmission program, the external storage device sequentially accumulates the logging data, and the logging monitoring function unit monitors the logging data stored in the external storage device.
Plant monitoring and control system. The plant monitoring and control system of claim 1, wherein when multiple models of PLC devices exist in the same system, the program generation function unit generates a data transmission program appropriate for each model of the PLC device. A plant monitoring and control system as described in claim 1 or 2, wherein the PLC device is provided with a separate Ethernet (registered trademark) unit, the logging setting function unit is provided with a connection method setting function unit that sets the connection method, and the program generation function unit generates a data transmission program according to the connection method of the Ethernet unit set by the connection method setting function unit. 3. The plant monitoring and control system according to claim 1, wherein, when a plurality of PLC devices exist in the same system, the logging setting function unit is provided with a transmission timing setting function unit that sets the transmission timing of the logging data at a period that is an integer multiple of the control period so that the transmission timing differs for each of the PLC devices , and the program generation function unit generates the data transmission program that is compatible with the transmission timing set by the transmission timing setting function unit. The plant monitoring and control system of claim 1 or 2, wherein the logging setting function unit includes a past value count setting function unit that sets the transmission timing of previously obtained logging data, a data transmission program is generated according to the transmission timing set by the past value count setting function unit, and the PLC device transmits previously obtained logging data based on the data transmission program.