JP7362590B2 - Telemeter and supervisory control system - Google Patents

Description

The present invention relates to telemeters and supervisory control systems.

Traditionally, there has been a monitoring and control system that imports data from a monitored object into a communication terminal installed at the site, transmits and displays the status of the monitored object to a remote location via communication, and sends commands to equipment at the site for remote control. Are known. For example, supervisory control systems are used in water supply and sewage systems, water distribution equipment, industrial production equipment, and the like (see, for example, Patent Document 1).

In such supervisory control systems, analog dedicated lines have been used as communication lines. Currently, the use of always-on networks such as broadband lines is increasing. However, due to the high communication costs of broadband lines and the fact that the service is often not provided at stations such as mountainous areas where construction of communication line facilities is required, there is still strong demand for dedicated lines.

A well-known water distribution method is to store tap water in tanks installed on high ground and distribute it to areas of demand using gravity-driven natural flow. Water treatment plants that produce tap water are located on flat land where it is easy to construct treatment facilities, so tanks and water treatment plants are often located in remote locations.

Therefore, it is necessary to use a pump to transport water from the water treatment plant to the tank. In such a pump, water level data of the tank is input into a control circuit, and control is performed such that the pump is stopped when the water level of the tank exceeds a specified value, and is started when the water level falls below the specified value.

In recent years, many dedicated line telemeters are of the form of a PLC (Programmable Logic Controller) with an additional transmission module compatible with the dedicated line. Input/output using contact signals is often used as a telemeter interface, and signals are often subjected to sequence processing before being output from the telemeter to the pump control circuit. Therefore, using PLC as a base, which is good at these processes, has advantages in terms of product development and actual operation.

JP 2016-1414 Publication

A dedicated line telemeter allows you to make voice calls while transmitting data by connecting telephones to the modems of the master and slave stations. There is no need to prepare a separate line for voice calls; data transmission and voice calls can be made on a single dedicated line, and water and sewage monitoring equipment is often located in remote areas where mobile phone signals cannot reach. , there is strong demand for voice calls over dedicated lines.

However, when using a modem with a transmission speed of 2400 bps or more, voice calls cannot be used due to the bandwidth used for data transmission.

SUMMARY OF THE INVENTION An object of the present invention is to provide a telemeter that allows data transmission and voice communication with a single transmission module even when using a modem with a high transmission speed.

A telemeter according to one aspect of the present invention is a telemeter that is connected to a dedicated line and has at least a transmission module, and the transmission module includes a calculation unit that creates a communication message, and a first modem having a first communication speed. a first port provided corresponding to the modem, and a second port provided corresponding to the second modem having a second communication speed slower than the first communication speed, The arithmetic unit may switch between first communication using the first modem and second communication using the second modem by switching between the first port and the second port.

A supervisory control system according to one aspect of the present invention is a supervisory control system in which a transmitting telemeter and a receiving telemeter are connected via a dedicated line, the transmitting telemeter having a first transmission module, The receiving side telemeter has a second transmission module, and the first transmission module corresponds to a first calculation unit that creates a communication message and a first modem having a first communication speed. a second port provided corresponding to a second modem having a second communication speed lower than the first communication speed; The arithmetic unit switches the first communication by the first modem and the second communication by the second modem by switching the first port and the second port, and the calculation unit switches the first communication by the first modem and the second communication by the second modem, and is a second calculation unit, a third port provided corresponding to the third modem having the first communication speed, and a third port corresponding to the fourth modem having the second communication speed. and a fourth port provided, and the second calculation unit switches between the third port and the fourth port to communicate between the first communication by the third modem and the fourth port. The present invention is characterized in that the second communication using the fourth modem is switched.

According to one aspect of the present invention, it is possible to provide a telemeter that allows data transmission and voice communication with one transmission module even when a modem with a high transmission speed is used.

FIG. 1 is a configuration diagram of a monitoring and reporting system in related technology. It is a figure which shows the processing content using a high-speed modem in related technology. It is a figure which shows the processing content using a low-speed modem in related technology. 1 is a configuration diagram of a monitoring and reporting system in Example 1. FIG. FIG. 3 is a diagram showing processing contents using a high-speed modem in Example 1. FIG. FIG. 3 is a diagram showing processing details using a low-speed modem in Example 1. FIG. FIG. 2 is a configuration diagram of a monitoring and reporting system according to a second embodiment.

First, with reference to FIG. 1, the configuration of a related technology monitoring and reporting system will be described.
A CPU module 410, a transmission module 420, a transmission module 430, and an I/O module 411 are installed on the PLC unit 400. The CPU module 410 executes telemeter software S4 that is created according to the transmission content, such as a ladder program, for example.

The transmission module 420 and the transmission module 430 are computers that can execute software on their own. The transmission module 420 and the transmission module 430 include a calculation unit 421 such as a microcomputer that executes software, a calculation unit 431, a base IF 422 and a base IF 432 for communicating with the CPU module 410, and a port 423 such as RS232C for communicating with a modem. It has a port 433, a communication speed setting switch 425, and a setting switch 435.

The communication speed setting switch 425 and the setting switch 435 are configured by, for example, a DIP switch, and are set by the user when constructing the dedicated line telemeter according to the communication speed of the modem connected to the ports 423 and 433. .

The CPU module 410 inputs and outputs signals to the I/O module 411, sends and receives data to the transmission module 420 and the transmission module 430, and sends and receives data to and from either the transmission module 420 or the transmission module 430 through the processing of the telemeter software S4. or switch.

The transmission module 420 and the transmission module 430 convert the data received from the CPU module 410 into a communication message for the dedicated line modem using software executed by the calculation unit 421 and the calculation unit 431, and convert the data received from the CPU module 410 into a communication message for the dedicated line modem 440 and the dedicated line. The communication message received from the modem 450 is converted into PLC data. At this time, the transmission module 420 and the transmission module 430 set the communication speed of the modem connected to the port 423 and the port 433 by setting the communication speed setting switch 425 and the setting switch 435 when converting between the communication message and the PLC data. , and performs conversion according to the communication speed.

A high speed modem 440 is connected to the port 423 of the transmission module 420, and a low speed modem 450 is connected to the port 433 of the transmission module 430. A telephone 460 is connected to the low-speed modem 450. High speed modem 440 and low speed modem 450 are connected to dedicated line 600 via relay 470.

An input terminal of a relay 470, a call switch 480, and a call reset switch 490 are connected to the I/O module 411. The states of the call switch 480 and the call reset switch 490 are transmitted to the dedicated line telemeter on the opposite side as a call identifier for the voice call.
The dedicated line telemeter on the opposite side is configured similarly.

FIG. 2 is a diagram showing processing details using a high-speed modem 440 in related technology.
Normally, when low-speed modem 450 is not used to make a call, relay 470 is switched to high-speed modem 440 side. The CPU module 410 on the sending side outputs data to the transmission module 420 connected to the high-speed modem 440 through the processing of the telemeter software S4.

The calculation unit 421 of the transmission module 420 converts the data acquired from the CPU module 410 into a communication message. Arithmetic unit 421 outputs the communication message from port 423 to high-speed modem 440 . High-speed modem 440 modulates the communication message output from transmission module 420 and outputs it to dedicated line 600 via relay 470.

On the receiving side, relay 570 is normally switched to high-speed modem 540 side. The signal output to dedicated line 600 is input to high-speed modem 540 via relay 570. High-speed modem 540 demodulates the communication message and outputs a signal to port 523 of transmission module 520. The calculation unit 521 of the transmission module 520 converts the communication message into PLC data and outputs it to the CPU module 510.

FIG. 3 is a diagram showing processing details using a low-speed modem 450 in related technology.
When starting a voice call, when the calling side presses the calling switch 480, a calling signal is input to the CPU module 410 via the I/O module 411. CPU module 410 outputs data including a call identifier to transmission module 420 to which high-speed modem 440 is connected. Transmission module 420 outputs the communication message from port 423 to high-speed modem 440 . High-speed modem 440 modulates the communication message output from transmission module 420 and outputs it to dedicated line 600 via relay 470.

On the receiving side, relay 570 is switched to high speed modem 540. The signal output to dedicated line 600 is input to high-speed modem 540 via relay 570. High speed modem 540 demodulates the communication message. The calculation unit 521 of the transmission module 520 converts the communication message into PLC data and outputs it to the CPU module 510.

Since the data call identifier is ON, the CPU module 510 outputs a switching signal to the low-speed modem side to the relay 570 via the I/O module 511. Further, the CPU module 510 changes the data output destination to the transmission module 530 through the processing of the telemeter software S5.

On the calling side, the CPU module 410 outputs a switching signal to the low-speed modem side to the relay 470 via the I/O module 411 after a specified period of time after turning on the calling identifier through the processing of the telemeter software S4. , changes the data output destination to the transmission module 430.

To end the voice call, when the caller presses the call reset switch 490, a call reset signal is input to the CPU module 410 via the I/O module 411. The CPU module 410 turns off the call identifier through the processing of the telemeter software S4. CPU module 410 outputs data to transmission module 430 to which low-speed modem 450 is connected. Transmission module 430 outputs the communication message from port 433 to high-speed modem 450. High-speed modem 450 modulates the communication message output from transmission module 430 and outputs it to dedicated line 600 via relay 470.

On the receiving side, relay 570 is switched to low speed modem 550. The signal output to the dedicated line 600 is input to the low-speed modem 550 via the relay 570. Low speed modem 550 demodulates the communication message. Since the call identifier is OFF, the CPU module 510 outputs a switching signal to the high-speed modem side to the relay 570 via the I/O module 230. Further, the CPU module 510 changes the data output destination to the transmission module 520 through the processing of the telemeter software S5.

On the calling side, the CPU module 410 outputs a switching signal to the low-speed modem side to the relay 170 via the I/O module 411 after a specified period of time after turning off the calling identifier through the processing of the telemeter software S4. , changes the data output destination to the transmission module 420.

In the above-mentioned related technology, when you want to perform transmission at speeds of 2400 bps or more and voice calls on one dedicated line, you can use a transmission module with a modem of 2400 bps or more connected to the PLC, and a transmission module with a modem of less than 2400 bps connected on the PLC. Use a telemeter that has both. Normally, high-speed transmission is performed using a modem and transmission module of 2400 bps or more, and when a voice call is desired, the transmission path is switched to a modem and transmission module of less than 2400 bps for communication.

As described above, in the above-mentioned related technology, it is necessary to use two transmission modules to switch between high-speed communication using a high-speed modem and low-speed communication using a low-speed modem, which complicates the processing.

In the present invention, communication using a high-speed modem and communication using a low-speed modem are switched using one transmission module.
Examples will be described below with reference to the drawings.

With reference to FIG. 4, the configuration of the monitoring and reporting system in Example 1 will be described.
A CPU module 110, a transmission module 120, and an I/O module 130 are installed on the PLC 100. In the CPU module 110, for example, telemeter software S1 such as a ladder program is executed.

The transmission module 120 is a computer that can execute software on its own. The transmission module 120 includes a calculation unit 121 such as a microcomputer that executes software, a base IF 122 for communicating with the CPU module 110, a port 123 such as RS232C for communicating with a high-speed modem, and a port 124 such as RS232C for communicating with a low-speed modem. and a communication speed setting switch 125.

The communication speed setting switch 125 is constituted by, for example, a DIP switch, and is set by the user when constructing the dedicated line telemeter in accordance with the communication speed of the modem connected to the port 123 and the port 124.

The CPU module 110 inputs/outputs signals to/from the I/O module 130 and transmits/receives data to/from the transmission module 120 through the processing of the telemeter software S1.

The transmission module 120 uses software executed by the calculation unit 121 to convert the data received from the CPU module 110 into communication messages for the dedicated line modem, and to convert the communication messages received from the dedicated line modems 140 and 150 into PLC data. Perform the conversion to

At this time, when converting between the communication message and the PLC data, the transmission module 120 determines the communication speed of the modem connected to the ports 123 and 124 based on the setting of the communication speed setting switch 125, and adjusts the communication speed to the communication speed. Perform the conversion. In addition, the transmission module 120 switches the port used for transmission and reception through processing to be described later, and adds a speed identifier to the communication message according to the communication speed set for the port.

A high speed modem 140 is connected to the port 123 of the transmission module 120, and a low speed modem 150 is connected to the port 124. A telephone 160 is connected to the low-speed modem 150. High speed modem 140 and low speed modem 150 are connected to dedicated line 300 via relay 170.

An input terminal of a relay 170, a call switch 180, and a call reset switch 190 are connected to the I/O module 130.
The dedicated line telemeter on the opposite side is configured similarly.

FIG. 5 is a diagram showing processing details using the high-speed modem 140 in the first embodiment.
Normally, when low-speed modem 150 is not used to make a call, relay 170 is switched to high-speed modem 140 side. The calculation unit 121 of the transmission module 120 on the sending side converts the data acquired from the CPU module 110 into a communication message.

The calculation unit 121 adds a speed identifier for the high-speed modem to the converted communication message. Further, the calculation unit 121 turns off the call identifier of the communication message. Arithmetic unit 121 outputs the communication message from port 123 to high-speed modem 140 . High-speed modem 140 modulates the communication message output from transmission module 120 and outputs it to dedicated line 300 via relay 170.

On the receiving side, relay 270 is normally switched to high-speed modem 240 side. The signal output to the dedicated line 300 is input to the high-speed modem 240 via the relay 270. The high-speed modem 240 demodulates the communication message and outputs a signal to the port 223 of the transmission module 220. The calculation unit 221 of the transmission module 220 converts the communication message into PLC data and outputs it to the CPU module 210.

FIG. 6 is a diagram showing processing details using the low-speed modem 150 in the first embodiment.
When starting a voice call, when the calling side presses the calling switch 180, a calling signal is input to the calculation unit 121 of the transmission module 120 via the I/O module 130 and the CPU module 110. The calculation unit 121 turns on the call identifier of the communication message. Arithmetic unit 121 outputs the communication message from port 123 to high-speed modem 140 . High-speed modem 140 modulates the communication message output from transmission module 120 and outputs it to dedicated line 300 via relay 170.

On the receiving side, the relay 270 is switched to the high speed modem 240 side. The signal output to the dedicated line 300 is input to the high-speed modem 240 via the relay 270. High speed modem 240 demodulates the communication message. Since the call identifier of the communication message is ON, the calculation unit 221 outputs a switching signal to the low-speed modem side to the relay 270 via the CPU module 210 and the I/O module 230. Furthermore, the calculation unit 221 changes the speed identifier of the communication message to one for a low-speed modem, and changes the output destination to the port 224.

On the calling side, if the speed identifier of the received data from the called side becomes undeterminable within a specified time after the calling identifier is turned ON, the calculation unit 121 determines that the called side has completed the call preparation, and the CPU A switching signal to the low-speed modem side is output to the relay 170 via the module 110 and the I/O module 130. Further, the calculation unit 121 changes the speed identifier of the communication message to one for a low-speed modem, and changes the output destination to the port 124.

To end the voice call, when the calling side presses the call reset switch 190, a call reset signal is input to the calculation unit 121 of the transmission module 120 via the I/O module 130 and the CPU module 110. Ru. The calculation unit 121 turns off the call identifier of the communication message.

The calculation unit 121 outputs the communication message from the port 124 to the low-speed modem 150. Low-speed modem 150 modulates the communication message output from transmission module 120 and outputs it to dedicated line 300 via relay 170.

On the receiving side, the relay 270 is switched to the low speed modem 250 side. The signal output to the dedicated line 300 is input to the low-speed modem 250 via the relay 270. The low speed modem 250 demodulates the communication message. Since the call identifier of the communication message is OFF, the calculation unit 221 outputs a switching signal to the high-speed modem side to the relay 270 via the CPU module 210 and the I/O module 230. Furthermore, the calculation unit 221 changes the speed identifier of the communication message to one for a high-speed modem, and changes the output destination to the port 223.

On the calling side, arithmetic unit 121 outputs a switching signal to the high-speed modem side to relay 170 via CPU module 110 and I/O module 130 after a predetermined time after turning off the calling identifier. Further, the calculation unit 121 changes the speed identifier of the communication message to one for a high-speed modem, and changes the output destination to the port 123.

With reference to FIG. 7, the configuration of the monitoring and reporting system in Example 2 will be described.
In the first embodiment shown in FIG. 4, the input terminal of the relay 170, the call switch 180, and the call reset switch 190 are connected to the I/O module 130. On the other hand, in the second embodiment, as shown in FIG. 7, it is arranged inside the transmission module 120, and input/output to the calculation unit 121 is performed without going through the CPU module 110. The rest of the configuration is the same as the configuration of the monitoring and reporting system in Example 1 shown in FIG. 4, so a description thereof will be omitted.

In the above embodiment, the transmission module is provided with two ports: a calculation section for creating a communication message with the PCL, and a port used for connecting the calculation section to the modem. A modem with a transmission speed of 2400 bps or more (hereinafter referred to as a high-speed modem) and a low-speed modem with a transmission speed of less than 2400 bps capable of voice notification are connected to each port. A switch, such as a relay, is installed at the end of the modem.

When the transmission module performs a transmission operation, the arithmetic unit creates a communication message to which a speed identifier for a high-speed modem and a speed identifier for a low-speed modem are added, and outputs it to each port. When a transmission module used for a communication message performs a receiving operation, the calculation unit determines whether the transmission is being performed by a high-speed modem or a low-speed modem, based on the speed identifier added to the communication message. Further, the arithmetic unit adds a call identifier for a voice call to the communication message.

In the above embodiment, in a supervisory control system consisting of a dedicated line and a telemeter, the arithmetic section in the transmission module is equipped with two ports for modem connection, and communication using a high-speed modem, communication using a low-speed modem, and voice calls are handled by one unit. This can be done by switching using the transmission module.

In addition, the calculation unit of the transmission module assigns a speed identifier for a high-speed modem or a speed identifier for a low-speed modem at the time of transmission, and upon reception, determines the communication speed of the modem from the assigned speed identifier, and selects the corresponding communication speed. Transmission is performed by

According to the above embodiment, on a PLC-based dedicated line telemeter, one transmission module can perform communication using a high-speed modem of the dedicated line and voice communication using a low-speed modem.

100 PLC
110 CPU module S111 Telemeter software 120 Transmission module 121 Arithmetic unit 122 Base IF
123 Port 124 Port 125 Communication speed setting switch 130 I/O module 140 High speed modem 150 Low speed modem 160 Telephone 170 Relay 180 Call switch 190 Call reset switch S1 Telemeter software 200 PLC
210 CPU module S211 Telemeter software 220 Transmission module 221 Arithmetic unit 222 Base IF
223 Port 224 Port 225 Communication speed setting switch 230 I/O module 240 High speed modem 250 Low speed modem 260 Telephone 270 Relay 280 Call switch 290 Call reset switch S2 Telemeter software 300 Dedicated line

Claims (11)

A telemeter connected to a dedicated line and having at least a transmission module,
The transmission module includes:
a calculation unit that creates a communication message;
a first port provided corresponding to a first modem having a first communication speed;
a second port provided corresponding to a second modem having a second communication speed lower than the first communication speed;
The arithmetic unit is
A telemeter characterized in that by switching the first port and the second port, first communication by the first modem and second communication by the second modem are switched. The arithmetic unit is
When sending,
When performing the first communication, assigning a first speed identifier for the first modem to the communication message and outputting it to the first port;
2. When performing the second communication, a second speed identifier for the second modem is added to the communication message and output to the second port. Telemeter. The arithmetic unit is
Upon receiving,
Determining whether the communication speed is the first communication speed or the second communication speed based on the first speed identifier or the second speed identifier given to the communication message,
If the result of the determination is the first communication speed, performing the first communication via the first port provided corresponding to the first modem;
2. If the result of the determination is the second communication speed, the second communication is performed through the second port provided corresponding to the second modem. Telemeter described in. The second modem is
having the second communication speed that allows voice calls;
The arithmetic unit is
2. The telemeter according to claim 1, wherein a call identifier of the voice call is added to the communication message. The transmission module includes:
The telemeter according to claim 1, further comprising a setting switch for setting the first communication speed and the second communication speed. The transmission module includes:
The telemeter according to claim 1, further comprising a built-in call switch and a call reset switch. A monitoring control system in which a transmitting telemeter and a receiving telemeter are connected via a dedicated line,
The transmitter telemeter is
a first transmission module;
The receiving telemeter is
a second transmission module;
The first transmission module includes:
a first calculation unit that creates a communication message;
a first port provided corresponding to a first modem having a first communication speed;
a second port provided corresponding to a second modem having a second communication speed lower than the first communication speed;
The first calculation unit is
Switching between the first communication by the first modem and the second communication by the second modem by switching the first port and the second port,
The second transmission module includes:
a second calculation unit;
a third port provided corresponding to a third modem having the first communication speed;
a fourth port provided corresponding to the fourth modem having the second communication speed;
The second calculation unit is
A supervisory control system characterized in that the first communication by the third modem and the second communication by the fourth modem are switched by switching the third port and the fourth port. The first arithmetic unit of the transmitter telemeter includes:
A first speed identifier for the first modem or a second speed identifier for the second modem is attached to the communication message, and the dedicated communication message is transmitted through the first port or the second port. output to the line,
The second arithmetic unit of the receiving telemeter includes:
Determining whether the communication speed is the first communication speed or the second communication speed based on the first speed identifier or the second speed identifier given to the communication message sent from the dedicated line. ,
If the result of the determination is the first communication speed, the first communication is performed via the third port provided corresponding to the third modem;
7. If the result of the determination is the second communication speed, the second communication is performed via the fourth port provided corresponding to the fourth modem. The supervisory control system described in . The second modem and the fourth modem are
having the second communication speed that allows voice calls;
The first arithmetic unit and the second arithmetic unit are
8. The supervisory control system according to claim 7, wherein the voice call is enabled using a call identifier given to the communication message. The first transmission module and the second transmission module are
8. The supervisory control system according to claim 7, further comprising setting switches for setting the first communication speed and the second communication speed. The first transmission module and the second transmission module are
8. The supervisory control system according to claim 7, further comprising a built-in call switch and a call reset switch.

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