JP2009188824A - Programmable controller and monitoring device employed therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a programmable controller and a monitoring device employed therefor which permit a user to easily check the state of automatic operation by obtaining information with respect to the output of a control signal to an on-site apparatus which is the control object of automatic operation and the execution of the on-site apparatus in accordance with the control signal to notify the obtained information to the user. <P>SOLUTION: The output of a control signal from an input and output unit 800 to the on-site apparatus 900 such as a pump or the like and the execution of the control signal inputted by the on-site apparatus 900 through the input and output unit 800 are informed to the user of the on-site apparatus from a communication unit 600 through a network 400 by a personal computer 100 or a mobile phone 200, for example. Accordingly, the user can easily check these outputs of the control signal and execution in the on-site apparatus. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention instructs a communication unit that performs communication via a network, an input / output unit that inputs / outputs signals to / from a field device, and an output of a control signal for the field device to the input / output unit. The present invention relates to a programmable controller including a control unit and a monitoring device used therefor.

  Conventionally, a programmable controller (hereinafter referred to as “PLC”) has been used as a controller for automating a machine based on a given dedicated user program in order to perform operation control of on-site equipment. There is known a control system for operating a device only for an arbitrary time by describing the start time and stop time of the device operation in a module in the user program. This method is hereinafter referred to as automatic driving.

  In the conventional control system described above, in many cases, set values such as a start time and a stop time are directly written in the user program. In addition, from the viewpoint of security, user programs are often prevented from being rewritten remotely. Therefore, in order to change the setting value, it is necessary to write the user program in which the new setting value is written directly to the PLC using a dedicated input tool.

  For example, a water supply / distribution facility for water and sewage is usually provided with a plurality of pumps for pumping water, and the operation time is determined and controlled for each pump. In order to reduce the electricity charge, nighttime electricity is used. In addition, when an emergency pump facility is provided, an operation test is regularly performed. Thus, in the PLC applied to the pump equipment, the control unit outputs a control signal of operation start and operation stop at a predetermined time, and operates a plurality of pumps only for a fixed time, The starting and stopping of each pump is an important confirmation for the user.

  Many PLCs have a communication function for exchanging data with software on PCs and other PLCs, but the user can directly check the operation status of the data and programs imported into the PLC. Does not have an interface function. For this reason, in order for the user to confirm whether or not the on-site equipment has been operated by automatic control, prepare a personal computer running dedicated software, record the data in the PLC's internal memory, and check the acquired data. There is a need to. For this reason, it has been difficult for the user to determine at the time of the control what kind of influence the field device has as a result of the automatic control.

The operating time at the time of equipment installation is registered in advance by initial setting, the equipment operating time and the elapsed time are counted, and when the count value reaches a threshold that is a preset maintenance cycle, a message is displayed. There has been proposed a water and sewage monitoring device that prevents maintenance from being forgotten or delayed in advance by performing a maintenance report by means of a voice display or the like, and aims for a stable supply of safe water (Patent Document 1). The monitoring device is connected to the network via the host device and has an input / output unit for inputting / outputting signals to / from the controlled device and an operation information notification function, and after the control change command to the controlled device It has been proposed to detect whether the operating state is abnormal and notify the host device (Patent Document 2). Furthermore, there has been proposed a monitoring device that compares a control signal of an operating state after a preset time with a reference value and transmits the comparison result (Patent Document 3).
Japanese Patent Laid-Open No. 11-361237 JP 2004-129280 A (paragraphs 0046, 0050, 0057) JP 06-242155 A (paragraphs 0022, 0023)

The above conventional problems are summarized as follows.
(1) It is difficult to confirm whether a control signal has been output.
In general, the PLC used for automatic control does not have a data display function. Therefore, in order to check whether the control signal is output to the control target as intended as a result of automatic operation, a dedicated software is required. It is necessary to install an installed personal computer, record operation signals of field devices and measurement data of other measurement devices, and confirm the recorded data by the user.
(2) It is difficult to confirm the result of the control.
As a result of outputting the control signal, to check whether the on-site equipment was operating as intended, and confirming whether the on-site situation was as expected as a result of operating the equipment, It is necessary for the user to check the recorded field device data and make a judgment.

Therefore, regarding automatic operation of field equipment, whether or not the control signal is output to the control target as intended and whether the field equipment operates as intended is not limited by time or place. There is a problem to be solved in that it can be easily confirmed by the user.
The object of the present invention is to acquire information on the output of a control signal to a field device to be controlled and the execution according to the control signal of the field device regarding the automatic operation of the field device, and It is to provide a programmable controller having a monitoring function that allows a user to easily check the state of automatic driving and a monitoring device used therefor.

Based on the above problems, the present invention attempts to respond as follows.
(1) Control by control program Not a PLC user program but another control program or a monitoring device having a communication function controls the control signal. Since a control program is incorporated in the PLC or the monitoring device in advance, the user can perform the same operation as the conventional automatic control only by setting conditions for controlling the start / end time and the like in the control program.
(2) Collection and notification of field device (machine field) data The PLC or monitoring device incorporates digital signals such as operation and failure of field devices and analog signals such as measurement values of measurement devices. When executing the control, the PLC or the monitoring device can notify the user of the execution of the control using an electronic mail. In addition, it is possible to perform notification by attaching the data of these field devices to the control execution notification mail.
(3) Determination of control success using field device (machine field) data A range of values that can be taken when control is successful is set in advance for machine field data that changes after control. It is determined whether the machine field data acquired after control is within the set range, and the determination result is described in the notification mail.

  A programmable controller according to the present invention or a monitoring device provided therein includes a communication unit that performs communication via a network, an input / output unit that performs input / output of a signal to / from a field device, and an output of a control signal for the field device. A programmable controller including a control unit that instructs the input / output unit, or a monitoring device included therein, wherein the control unit outputs the control signal to the field device and the field signal of the control signal. The execution of is notified to the user of the field device via the network from the communication unit.

  In the programmable controller according to the present invention or the monitoring device provided therein, the communication unit indicates that the control signal is output from the input / output unit to the field device and that the field device executes the control signal input through the input / output unit. Therefore, the user can easily confirm the output of these control signals and the execution thereof in the field device.

(1) Sending the control result Since the execution of the control is notified via the network, if the user can connect to the network without preparing a personal computer on which data collection software is installed, the control result will be displayed. Can be confirmed. Furthermore, if there is an environment in which an e-mail can be received, the e-mail can also be received by a mobile phone, so that the control result can be easily confirmed even when away from home.
(2) Transmission of field device data Since it is possible to transmit the control execution notification by attaching machine field data such as measurement data of the field device after the control, the influence of the control execution can be determined instantaneously.
(3) Automatic determination of control results After the control is executed, whether or not the user has executed the control in order to determine whether the data value of the field device is set in advance and within the range, and to automatically notify the determination result As a result of executing the control, it is possible to instantly confirm whether or not the field device has operated as expected.

  Hereinafter, an embodiment of a monitoring device according to the present invention will be described with reference to the drawings. FIG. 1 shows the overall configuration of a control system according to the present invention. The personal computer 100 can be connected to a programmable controller (hereinafter abbreviated as “PLC”) 500 via a communication line 400 such as the Internet. The PLC 500 controls the communication unit 600 that transmits data via the communication line 400 and the control signal to the input / output unit 800 in accordance with the set schedule or by looking at the input signal from the input / output unit 800. A control unit 700 that determines success / failure of the device, and an input / output unit 800 that outputs a control signal to the connected field device 900 that is a control target or inputs a signal from the field device 900. The user's mobile phone 200 can be connected to the communication line 400 via the mobile phone communication network 300.

  The user uses the personal computer 100 to set setting values such as control start / end times and a reference value for success determination of the control result in the PLC 500 via the communication line 400. In PLC 500, the setting value received by communication unit 600 is set in a control program in control unit 700.

  At the set time, the control unit 700 outputs the control signal of the field device 900 to the input / output unit 800, and the input / output unit 800 receiving the instruction outputs the control signal to the field device 900. When the control signal is output, the control unit 700 instructs the communication unit 600 to transmit a notification mail, and the communication unit 600 transmits a control execution notification mail via the communication line 400 and the mobile phone communication network 300. It is transmitted to the telephone 200. Further, the machine field data transmitted from the field device 900 is also input to the input / output unit 800, and the machine field data is sent to the control unit 700. The machine field data sent to the control unit 700 is used to determine whether control is successful. The communication unit 600 transmits the determination result of the success or failure of the control to the user by attaching it to the notification mail together with the machine data itself.

  FIG. 2 shows the timing of notification. When the field device (900 shown in FIG. 1) starts or stops operation in response to the control signal 1000 from the PLC (500 shown in FIG. 1), transmission from the field device to the PLC requires Some response signals (digital) 1100, such as ON / OFF operations, are transmitted, and some response signals (analog) 1200, such as measurement data of physical quantities such as flow rate and temperature that indicate the degree of operation of field equipment. . In general, the response signal (digital) 1100 of the field device has a relatively short delay (time lag) with respect to the output of the control signal 1000 from the PLC, but the response speed of the physical quantity is slow. There is a time lag longer than the response signal (digital) 1100 to change and saturate (stable to a constant output).

  When notifying the operation status of the field device to the user, not only the on / off of the field device but also the change in the subsequent operation state, the information represented by the response signal (analog) 1200 You will be notified. In such a case, the user can confirm whether or not the field device has responded correctly in response to the output of the control signal, that is, the changing response signal is not only in its transition state but also in a sufficiently saturated state, that is, has finished changing. There is a need to know the signal to the state.

  Therefore, first, at a time set by the user, it is assumed that the PLC outputs a control signal 1000 for operation control of the field device to be controlled, and the field device starts operation accordingly. A response signal (digital) 1100 is input to the PLC from the field device. However, there is a relatively short time lag from when the control signal 1000 is output until the response signal (digital) 1100 starts to be output, and the change of the response signal (analog) 1200 is gradual. Has a relatively long time lag. Therefore, the notification about the start of operation of the on-site equipment from the PLC to the user is performed at a timing at which the change of the response signal (analog) 1200 seems to have been sufficiently settled. In the notification of the end of operation of the on-site equipment, as in the case of the start of operation, the response signal (digital) 1100 passes after a relatively short time lag after the operation end control signal is output, and the response signal (analog ) Since each signal becomes stable after a relatively long time lag with respect to 1200, as a result, the PLC notifies the user of the end after a certain time when the change of the response signal (analog) 1200 has settled down. Send.

  Since the time from the start of control until the response signal (digital) 1100 or the response signal (analog) 1200 changes depends on the type and characteristics of the field device or system, the timing of notification is determined by the user. It can set appropriately in PLC based on a test result etc.

  For the output and execution of the control signal, the user not only signals that the operation has been started / stopped, such as ON / OFF of the on-site equipment, but also how the operating state changes according to ON / OFF. It can be confirmed by e-mail via a communication network such as a mobile phone communication network without being constrained by the place, although there is a condition that the communication state can be secured such as daytime or nighttime. .

FIG. 3 shows a detailed comparison of the device configuration between the conventional automatic control and the method according to the present invention.
A conventional control system is shown in FIG. The PLC 1400 used in the conventional control system has a configuration in which a CPU module 1500 that controls the PLC 1400 and an input / output module 1700 that inputs and outputs digital signals and analog signals are installed on the base module 1600. In the case of automatic control, the user program is stored in the PLC control unit 1600 in the CPU module 1500 and executed. In order to write the user program to the PLC, the user needs to write the personal computer 1300 directly to the CPU module 1500 on site. When the time specified by the user program is reached, the control unit 1600 instructs the input / output unit 1800 in the input / output module 1700 to output a control signal via the base module 1900, and the control signal is sent from the input / output module 1700 to the field device 2400. Is output.

  The automatic control of the scheme according to the invention is shown in FIG. In the system according to the present invention, in addition to the CPU module 1500 and the input / output module 1700, the monitoring device 2100 is also installed on the base module 1900 as a PLC module, and communicates with the CPU module 1500 via the base module 1900. The monitoring device 2100 is connected to the communication line 2000 using the communication unit 2200. Therefore, the user connects the personal computer 1300 to the monitoring device 2100 from a remote location via the communication line 2000, and sets the control start time and control end time in the monitoring device control unit 2300 of the monitoring device 2100. When the set time comes, the monitoring device control unit 2300 instructs the PLC control unit 1600 in the CPU module 1500 to output a control signal for control start or control end. Upon receiving the instruction, the PLC control unit 1600 instructs the input / output unit 1800 in the input / output module 1700 to output a control signal, whereby the control signal is output from the input / output module 1700 to the field device 2400.

  The monitoring device control unit 2300 collects input signals to the input / output module 1700 via the PLC control unit 1600. The collected data is used when the monitoring device control unit 2300 determines a control result. When the control signal is output, the monitoring device control unit 2300 instructs the communication unit 2200 to transmit a notification mail, and the communication unit 2200 transmits a control execution notification mail to the user via the communication line 2000. .

  As a programmable controller according to the present invention or a monitoring device therefor, a water supply / distribution system for water and sewage systems has been described as an example. However, the present invention is not limited to this, and FA is an industrial automated production facility. (Factory automation), PA (process automation), sales data collection equipment, or HA (home automation), etc., can be applied to various fields to be automated. The response signal (digital) is typically an ON / OFF signal of each device that is automated, and the response signal (analog) is measurement data of various physical quantities acquired for the automation.

The system diagram which shows an example schematic structure of the whole control system. The time chart which shows an example of the timing which performs notification. Explanatory drawing of the control system by this invention. Explanatory drawing of the conventional control system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 PC 200 Cellular phone 300 Cellular phone network 400 Communication line 500 Programmable controller 600 Communication unit 700 Control unit 800 Input / output unit 900 Field device 1000 Control signal 1100 Response signal (digital)
1200 Response signal (analog) 1300 PC 1400 PLC 1500 CPU module 1600 PLC controller 1600 1700 I / O module 1800 I / O unit 1900 Base module 2000 Communication line 2100 Monitoring device 2200 Communication unit 2300 Monitoring device control unit 2400 Field device

Claims (6)

A communication unit that communicates via a network, an input / output unit that inputs and outputs signals to and from the field device, and a control unit that instructs the input / output unit to output a control signal for the field device A programmable controller comprising:
The control unit is configured to notify the user of the field device from the communication unit via the network of the output of the control signal to the field device and the execution of the control signal in the field device via the network. controller. The programmable controller according to claim 1,
The said communication part performs the notification to the said user via the said network with an email, The programmable controller characterized by the above-mentioned. The programmable controller according to claim 1 or 2,
The said control part records the driving | running state of the said field device acquired through the said input / output part at the time of the output of the said control signal, and includes the said driving | running state in the notification to the said user. The programmable controller according to any one of claims 1 to 3,
The control unit determines success or failure of execution of the control signal according to whether or not an operation state of the field device acquired after execution of the control signal in the field device matches a preset content. The programmable controller characterized by including the said determination content in the notification to. In the programmable controller of any one of Claims 1-4,
The said control part issues the notification to the said user at the timing which considered the time lag which arises when the said field device outputs a response signal with respect to execution of the said control signal. A communication unit that communicates via a network, an input / output unit that inputs and outputs signals to and from the field device, and a control unit that instructs the input / output unit to output a control signal for the field device A monitoring device used in a programmable controller comprising:
The control unit detects the output of the control signal from the input / output unit to the field device, and the execution of the control signal input through the input / output unit in the field device, and outputs and executes the control signal. To the user of the field device via the network from the communication unit.

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