JPH047877B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transmission method between a master station and a group of slave stations each having a different function, and particularly to a transmission method that can increase the transmission speed.

[Conventional technology]

In general, as shown in FIG. 5, a master station 40 and a plurality of slave station groups having terminal devices with control and controlled functions are considered to be one slave station group, and the plurality of slave stations are connected to a common transmission path. 50 is called a multipoint or multidrop network method.

In such a network system, the master station selects a slave station by adding the slave station address to the transmission request signal, or polling signal, or reception request signal, or selecting signal, or data sent from the master station. Communication with each slave station is carried out sequentially for each address using means such as transmitting data. An outline of this polling/selecting method is shown in FIG.

FIG. 6a shows polling in which the master station requests transmission in order to collect data from each slave station. First, a transmission request signal (polling signal) is transmitted from the master station to the slave station. In response, the slave station sends back the data if it has data, and a transmission end signal if there is no data, and the master station also sends a transmission confirmation signal.

FIG. 6b shows selecting in which the master station requests each slave station to receive data. First, the master station transmits a reception request signal (selecting signal) to the slave stations. In response, the slave station replies with a receivable signal, which causes the master station to transmit data, and furthermore, the slave station replies with a transmission confirmation signal.

[Problem that the invention seeks to solve]

As described above, communication data in this method is transmitted while transmission confirmation is performed, and therefore, there is an advantage that the reliability of the communicated data is high. but,
On the other hand, it has the disadvantage of poor transmission efficiency, and as the number of slave stations connected to the master station 40 via the common transmission path 50 increases, the time it takes to complete communication with all slave stations, that is, one scan becomes longer, and thus the transmission time becomes longer. Therefore, it was not suitable for a remote monitoring and control system with a large number of control units.

The present invention has been made in view of the problems of the conventional method, and aims to significantly shorten data transmission time.

[Means for solving problems]

In order to achieve this object, the remote monitoring and control system of the present invention includes a first slave station group consisting of a plurality of slave stations each having a terminal device equipped with control data input/output and monitoring data input functions; a second slave station group consisting of a plurality of slave stations each having a terminal device having input and monitoring data output functions, and a third slave station group consisting of a plurality of slave stations having terminal devices mainly having a monitoring data output function. In a remote monitoring and control system comprising a group of slave stations, each slave station group and the master station are connected through a transmission path, and transmission is performed between the master station and each slave station group using a polling/selecting method. , a transmission line connecting the master station and each slave station group is arranged independently for each slave station group, the same address is given to the corresponding slave stations in each slave station group, and each slave station is It is characterized by transmitting monitoring and control data by simultaneously polling or selecting a group of slave stations.

[Effect]

FIG. 1 shows a connection system of a transmission system according to the present invention. In this system, each slave station group 1, 2, 3 having terminal equipment with different functions uses an independent transmission line 10, 20, 30 for each slave station group.
The slave stations (1-1, 2-1, 3-1) of each slave station group 1, 2, and 3 have the same address and correspond to each other. The same applies to other corresponding slave stations.

FIG. 2 shows an overview of the polling and selecting method according to the present invention. Figure 2a shows polling in which the master station makes a transmission request to collect data from each slave station. First, the master station sends a [transmission request signal + data] to the slave stations as a polling signal. Send. In response, the slave station replies with [transmission end signal + data]. Second
FIG. b shows selecting in which the master station requests each slave station to receive data. First, the master station transmits [reception request signal + data] to the slave stations as a selecting signal. In response, the slave station replies with [transmission confirmation signal + data].

The above polling/selecting method is simpler than the commonly used polling/selecting method, but if there is always a reply to polling or selecting, the The reliability of communication data is not impaired in any way. If there is no reply,
It is sufficient to perform polling or selection again.

FIG. 3 shows a timing chart of simultaneous polling or selection from a master station to slave stations having the same address in each corresponding slave station group.

In Figure 3, the master station sends [transmission request signal + data] as transmission data to the slave stations 1-1, 2-1, and 3-1 having the same address in each slave station group in the case of polling. transmit at the same time, slave station 1
-1, 2-1, and 3-1 simultaneously return [transmission end signal + data] as reply data.

In the case of selecting, [reception request signal + data] is simultaneously transmitted as transmission data, and slave station 1-
1, 2-1, 3-1 are [transmission confirmation signal + data]
are sent as reply data at the same time. Note that the reply data from the slave station 2-1 is not normally used, but is used especially when control is desired.

FIG. 4 shows the transmission format for communication between the master station and slave station groups 1, 2, and 3. Even though the transmission formats sent from the master station to slave station group 1 and slave station groups 2 and 3 and the reply formats sent back to the master station from slave station group 1 and slave station groups 2 and 3 are different, the master station By making the transmission paths (1, 2, 3) that connect the slave station groups 1, 2, and 3 independent, simultaneous transmission from the master station to the slave stations with the same address in the slave station groups 1, 2, and 3 Polling or selecting can be performed.

〔Example〕

Hereinafter, the present invention will be explained in detail based on specific examples.

In Figure 1, slave station group 1 is positioned as the motor control center side that can be directly operated and controlled, slave station group 2 as the monitoring panel side that mainly monitors, and slave station group 3 as the field operation panel side that can be remotely operated and controlled. The operation of one slave station at this time will be explained as follows based on the transmission format shown in FIG.

(a) [Transmission when performing direct operation control from the control center side (slave station group 1)] The master station transmits to each slave station of slave station groups 1, 2, and 3,
Polling or selecting is performed simultaneously via transmission lines 10, 20, and 30 in FIG. At this time, the polling or selecting transmission data is in the respective transmission format, and the reply data is in the respective reply format. However, the transmission format at the time of polling is to transmit all the monitoring or control data parts as 0, and the transmission format at the time of selecting is to transmit only the monitoring or control data part as data when there is a change. At this time, the analog data transmitted by each slave station in the slave station groups 2 and 3 is transmitted as analog data in the transmission format, regardless of polling or selection.

In the above, control data input by operating a terminal device on the side of slave station group 1, such as a push button switch, is input to the data transmission control section of the slave station of slave station group 1. At this time, since the master station is performing normal polling, the data in the polling transmission format created by the data transmission control unit is sent from each communication unit to each slave station in slave station groups 1, 2, and 3. , slave station group 1, 2, 3
simultaneously to each corresponding slave station.

After the transmitted transmission data is input to the reception section of the slave station of each slave station group, it is collated and verified in the data transmission control section, and each slave station of slave station groups 2 and 3 receives the analog data before this polling. Only the output signal is output to a terminal device such as an ammeter. The slave stations of slave station group 1 do not output to terminal devices such as electromagnetic switches. In addition, the reply data for polling is data in the reply format created by the data transmission control unit of the slave station of each slave station group.
Reply simultaneously by the transmitter of the slave station of each slave station group,
The master station inputs reply data from each slave station to each slave station through a receiving section.

The input reply data from the slave stations of slave station groups 1 and 3 is collated and verified by the data transmission control unit and then stored. Since the slave station group 2 mainly performs only monitoring, the reply data from the slave stations of the slave station group 20 is not taken into the data transmission control unit of the master station in the case of monitoring.

(a-1) When the reply data from the slave stations of slave station groups 1 and 3 stored in the data transmission control unit of the master station is the reply data of the slave stations of slave station group 1. The control data from the push button switch is stored as control data A in the reply format, and the analog data is stored as analog data at the time of polling.

(a-2) In the case of reply data from the slave stations of slave station group 3 Since direct operation control is performed from the control center side, there is no change in the control data, and the control data B- in the reply format
1 and B-2 are stored as unchanged data.

The above is the communication situation for the first scan polling performed between the master station and the corresponding slave stations of each slave station group. Note that the control data C is dummy data to improve transmission reliability and is not directly involved in control. Furthermore, the control data D is dummy data other than the reset data sent from the master station when a power outage or control error occurs, and the control data D is dummy data.
has the same effect.

Next, the master station uses the changed control data A already stored in the data transmission control unit to
The scan starts the selection process.

The master station transmits the data in the transmission format created by the data transmission control unit at the time of selection from the transmission unit to each slave station in the slave station groups 1, 2, and 3 to the corresponding one of the slave station groups 1, 2, and 3. Send to each slave station simultaneously.

In this transmission, (a-3) In the case of transmission to the slave stations of slave station group 1, the already stored control data A is changed in the data transmission control section to change the control data A on the selecting transmission format. This transmission data is transmitted from the transmitter to the slave stations of slave station group 1.

The transmitted data is input to the data transmission control section from the reception section of the slave station of the slave station group 1, and after verification and verification, is output to a terminal device, such as an electromagnetic switch, to execute control. At this time,
Electromagnetic switches, etc. operate electric motors or control indicators, etc.

In addition, as an answer back signal, a contact signal such as an electromagnetic switch and a current value of the motor are input to the data transmission control section of the slave stations of slave station group 1,
Create reply data by changing the monitoring data and analog data on the reply format,
The transmitter sends a reply to the master station. Here, the reply data sent back to the master station is input from the receiving section to the data transmission control section, and is stored after verification and verification.

(a-4) In the case of transmission to each slave station in slave station groups 2 and 3, the data transmission control unit of the master station transmits the unchanged previous data to the monitoring data on the selecting transmission format. Regarding the analog data, analog data at the polling time of the first scan is created, and is transmitted from the transmitter to each slave station in the slave station groups 2 and 3 as transmission data.

The transmitted transmission data is input to the data transmission control unit from the reception unit of each slave station in slave station groups 2 and 3, and after verification and verification, it is output to terminal devices such as displays and ammeters for control. .

Furthermore, the reply data resulting from the selection is returned from the transmitting section of each slave station to the master station as reply data in a reply format created by the data transmission control section of each slave station.
The reply data at this time is similar to the reply data to the polling for the first scan, the control data B-1 and B-2 are returned as unchanged data, and the master station is sent back to the slave station groups 2 and 3.
The return data from the slave stations of the slave station group 3 is input to the data transmission control unit and stored therein.

Note that the reply data from the slave stations of the slave station group 2 at this time is not taken into the data transmission control section of the master station because the slave station group 2 mainly performs only monitoring.

The above is the selection communication situation in the second scan.

However, during the selection of the second scan, the returned answer back signal monitoring and analog data are not sent to slave station groups 2 and 3 and remain stored in the data transmission control unit of the master station. It's summery.

Therefore, by transmitting the monitoring and analog data to each of the slave stations of the slave station groups 2 and 3, control and monitoring communication for the corresponding slave station of each slave station group is completed. Therefore,
In order to monitor the answer back signal and send analog data to each slave station in slave station groups 2 and 3,
The third scan is the start of selection again.

The master station transmits data in the transmission format at the time of selection created by the data transmission control unit as transmission data to each of the slave stations in the slave station groups 1, 2, and 3.
3 slave stations at the same time.

In the above transmission, (a-5) In the case of transmission to a slave station of slave station group 1, the data transmission control unit converts the control data A already stored in the data transmission control unit of the master station into a selecting transmission format. Create the transmission data as the control data A above, and send it from the transmitter to the slave stations of slave station group 1, and the slave stations should reply with the same reply data as the reply data returned in the second scan. This means that the control and monitoring communication has ended.

(a-6) For transmission to each slave station in slave station groups 2 and 3 The data transmission control unit selects the answer back signal monitoring and analog data already stored in the data transmission control unit of the master station. monitoring and analog data on the transmission format of the transmitter, and transmits it as transmission data from each transmitter to each slave station in slave station groups 2 and 3, and by transmitting it to the slave stations in slave station group 2, This means that the monitoring communication has ended.
Furthermore, the control and monitoring communication is completed by the reply data that is the same as the reply data returned in the second scan from the slave stations of the slave station group 3.

The control and monitoring communication described so far is only for one slave station corresponding to slave station groups 1, 2, and 3, and all of the corresponding slave stations of slave station groups 1, 2, and 3 This means that control and monitoring communications can be repeated for all slave stations.

(b) [Transmission when performing remote operation control from the field operation panel side (slave station group 3)] Control data input by operating the push button switch, which is a terminal device on the slave station group 3 side, is transmitted to the slave station group 3
The data is input to the data transmission control unit of the slave station.
At this time, the master station is performing normal polling, so the data in the polling transmission format created by the data transmission control section is
Each transmitter for each of the child stations in child station groups 1, 2, and 3 simultaneously transmits to each corresponding child station in child station groups 1, 2, and 3.

After the transmitted transmission data is input to the reception section of the slave station of each slave station group, it is collated and verified in the data transmission control section, and each slave station of slave station groups 2 and 3 receives the analog data before this polling. output only to a terminal device such as an ammeter.

The slave stations of slave station group 1 do not output to terminal devices such as electromagnetic switches.

Further, as reply data to polling, data in a reply format created by the data transmission control section of each slave station is inputted from a receiving section corresponding to each slave station.

The input reply data from the slave stations of slave station groups 1 and 3 is collated and verified by the data transmission control unit and then stored. Furthermore, since the slave station group 2 mainly performs only monitoring, the reply data from the slave stations of the slave station group 2 is not taken into the data transmission control unit of the master station.

(b-1) When the reply data from the slave stations of slave station groups 1 and 3 stored in the data transmission control unit of the master station is the reply data of the slave stations of slave station group 1: Far from the field operation panel side Since operation control is being performed, the control data does not change, and the monitoring and control data A in the reply format is stored as unchanged data, and the analog data is stored as analog data at the time of polling.

(b-2) In the case of reply data from a slave station in slave station group 3 The control data from the push button switch that has already been input is treated as control data B-1 on the reply format, and B-2 is changed. Each is stored as data that has not been updated.

The above is the communication status for the first scan polling performed between the master station and the corresponding slave stations of each slave station group.

Note that the control data C is dummy data to improve transmission reliability and is not directly involved in control. Further, the control data D is dummy data other than the reset data sent from the master station when a power outage or control error occurs, and has the same effect as the control data C described above.

Next, the master station starts selecting in the second scan using the changed control data B-1 already stored in the data transmission control section. The master station transmits data in the transmission format created at the time of selection to each slave station in slave station groups 1, 2, and 3 by the data transmission control unit. Send to each slave station simultaneously.

In the above transmission, (b-3) In the case of transmission to a slave station of slave station group 1: Control data B-1 that is already stored
In the data transmission control section, control data B- on the selecting transmission format is transmitted.
Transmission data is created by changing 1, and this transmission data is transmitted from the transmitter to the slave stations of slave station group 1.

The transmitted transmission data is input to the data transmission control unit from the receiving unit of the slave station of slave station group 1,
After verification and verification, it is output to a terminal device such as an electromagnetic switch to execute control. At this time, the electromagnetic switch or the like operates the electric motor or controls the display or the like. In addition, as an answer back signal, a contact signal such as an electromagnetic switch and a current value of a motor are input to the data transmission control section of the slave stations of slave station group 1, and a reply is sent that changes the monitoring data and analog data on the reply format. Create data and send it back to the master station from the transmitter.

Here, the reply data sent back to the master station is
The data is input from the receiving section to the data transmission control section, and is stored after verification and verification.

(b-4) In the case of transmission to each slave station in slave station groups 2 and 3, the data transmission control unit of the master station transmits the unchanged previous data to the monitoring data on the selecting transmission format. Regarding the analog data, the analog data at the time of polling of the first scan is created, and sent from the transmitter to the slave station group 2, as reply data.
The data is sent to each of the 3 slave stations.

The transmitted transmission data is input to the data transmission control unit from the reception unit of each slave station in the slave station groups 2 and 3, and after verification and verification, is output to a terminal device such as a display or an ammeter for control. Furthermore, the reply data resulting from the selection is sent back from the transmission section of each slave station to the master station using the data in the reply format created by the data transmission control section of each slave station as the reply data. The reply data at this time is similar to the reply data for the first scan polling, control data B-1 is returned as changed data, control data B-2 is returned as unchanged data, and the master station Data is input from the receiving section for each slave station in slave station groups 2 and 3, and reply data from the slave stations in slave station group 3 is input and stored in the data transmission control section. Note that the reply data from the slave stations of the slave station group 2 at this time is not taken into the data transmission control section of the master station because the slave station group 2 mainly performs only monitoring.

The above is the selection communication situation in the second scan.

However, during the selection of the second scan, the returned answer back signal monitoring and analog data are not sent to slave station groups 2 and 3 and remain stored in the data transmission control unit of the master station. It's summery. Therefore, by transmitting the monitoring and analog data to each of the slave stations of the slave station groups 2 and 3, control and monitoring communication for the corresponding slave station of each slave station group is completed. Therefore, in order to monitor the answer back signal and transmit analog data to each slave station in the slave station groups 2 and 3, the third scan is the start of selection again. The data transmission control section of the master station transmits data in the transmission format created at the time of selecting as transmission data to each of the slave stations of slave station groups 1, 2, and 3. Send to each slave station simultaneously.

In the above transmission, (b-5) In the case of transmission to a slave station of slave station group 1, the data transmission controller selects the control data B-1 already stored in the data transmission controller of the master station. Create transmission data as control data B-1 in the transmission format, and send it from the transmitting unit to the slave stations of slave station group 1, and the slave stations send reply data that is the same as the reply data returned in the second scan. A reply means that the control and monitoring communication has been completed.

(b-6) In the case of transmission to each slave station in slave station groups 2 and 3 The data transmission control unit selects the answer back signal monitoring and analog data already stored in the data transmission control unit of the master station. monitoring and analog data on the transmission format of the transmission, and is sent as transmission data from each receiving unit to each slave station in slave station groups 2 and 3, and sent back from the slave station in slave station group 3 in the second scan. By sending back the same reply data as the received reply data, the control and monitoring communication is completed.

The control and monitoring communication described so far is only for one slave station corresponding to slave station groups 1, 2, and 3, and all the corresponding slave stations of slave station groups 1, 2, and 3 This means that communication for station control and monitoring can be repeated for all the slave stations.

〔Effect of the invention〕

As described above, in the present invention, in the polling/selecting method, groups of corresponding slave stations with different functions are connected through independent transmission paths, so it is not possible to assign the same address to a group of corresponding slave stations. can. In addition, even though the transmission formats used for communication between the master station and each slave station group are different, polling or selection performed from the master station to each slave station group is performed by the same address of each slave station group. This can be done simultaneously for all stations.

If transmission is to be carried out between a master station and each corresponding slave station group with different functions using polling and selection in the conventional multi-network system, each slave station in each slave station group will have a different address. However, the present invention assigns the same address and transmits simultaneously, and the transmission procedure is simplified, so for example, for three slave station groups, the transmission speed is more than three times that of the conventional method. can be realized. Furthermore, compared to the conventional remote monitoring and control system using polling and selection using a multi-network system, the transmission speed is faster, so more monitoring and control equipment can be configured. Furthermore, since the slave stations in each slave station group have a mixture of digital and analog data functions, an economical system configuration can be achieved.

[Brief explanation of drawings]

FIG. 1 is a connection diagram of the network system according to the present invention, FIG. 2 is an explanatory diagram of communication data for polling and selecting of the present invention, and FIG. 3 is an explanation of polling or selecting for each slave station group of the present invention. 4 is an explanatory diagram of the transmission format of the present invention, and FIG. 5 is a connection diagram of the conventional network system.
FIG. 6 is an explanatory diagram of conventional polling and selecting. 1, 2, 3: slave station group, 10, 20, 30: transmission path, 40: master station.

Claims (1)

[Claims] 1. A first slave station group consisting of a plurality of slave stations each having a terminal device having control data input/output and monitoring data input functions, and a plurality of slave stations having terminal devices having control data input and monitoring data output functions. a second slave station group consisting of a plurality of slave stations, and a third slave station group consisting of a plurality of slave stations mainly having a terminal device equipped with a monitoring data output function, and each slave station group and the master station are connected to each other. The polling and
In a remote monitoring and control system that performs transmission between a master station and each slave station group using a selecting method, a transmission path connecting the master station and each slave station group is arranged independently for each slave station group. The remote control system is characterized in that the same address is given to corresponding slave stations in each slave station group, and polling or selection is performed from the master station to each slave station group simultaneously to transmit monitoring and control data. Transmission method in supervisory control system.