JPH01277098A - Supervisory control system - Google Patents

Abstract

PURPOSE:To decide the state of a station to be supervised based on the presence/absence of a response signal by providing a folding switch in the station to be supervised, and returning a call signal only when a supervisory item is normal at the time of detecting the call signal with a regular frequency. CONSTITUTION:When a logic circuit 11 for a supervisory station indicates the station to be supervised to a regular frequency oscillation circuit 12, the circuit 12 sends the call signal with the regular frequency to an up transmission channel 3. When a regular frequency detection circuit 21 detects a frequency allocated to its own station, the output of the circuit 21 goes to 1, and it is supplied to one side of an AND gate 23. At this time, when no abnormality exists in the supervisory item, 1 is also supplied to the other side of the gate 23. and the output of the gate 23 goes to 1, then, the folding switch 2 is set at an ON state. In such a way, a detected signal with the regular frequency is returned to a supervisory station side via a down transmission channel 4. A regular frequency detection circuit 13 detects a folded signal, and recognizes the normality of the supervisory item of the station to be supervised.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a monitoring control system suitable for remote monitoring using, for example, a wireless line. The present invention relates to a monitoring control method in which a station sends back a response signal and monitors the status of a monitored station according to the returned information.

[Prior Art] Conventionally, in a remote monitoring system using a wireless line, a monitored station receives an FSX-modulated paging signal from the monitoring station, demodulates it, and then converts the demodulated paging signal into a self-transformer. It checks whether the call signal is addressed to itself, and if it is addressed to itself, it multiplexes and encodes multiple monitoring items to generate a response signal, which is FSX-modulated and sent back to the monitoring station. was.

[Problems to be Solved by the Invention] However, in such a conventional supervisory control system, the monitored station is equipped with a communication circuit such as an FSX demodulation circuit, a calling signal detection circuit, a multiplexing/encoding circuit, and an FSK modulation circuit. A large number of circuits are required.

Therefore, there was a problem in that the amount of power consumed by the monitored station also increased. In particular, when a monitored station is installed at each of a large number of monitoring points, the conventional system has a problem in that the power consumption of the entire system becomes extremely large.

The present invention has been made in view of such problems, and includes:
The purpose of this invention is to provide a supervisory control method that can significantly reduce the power consumption of a monitored station.

[Means for Solving the Problems] The supervisory control system according to the present invention includes a supervisory station supervisory control device provided in a monitoring station and a monitored station supervisory control device provided in a monitored station as follows. It is characterized by its composition.

A monitoring control device for a monitoring station includes a means for transmitting a calling signal of a specified frequency assigned to the monitored station to be monitored to the monitored station via a communication line, and a means for transmitting the calling signal from the monitored station as a response signal. and means for determining the state of the monitored station depending on the presence or absence of this detection.

Further, the monitoring control device for a monitored station includes a means for outputting a monitoring item signal indicating the presence or absence of an abnormality in the monitoring item, a means for detecting a calling signal of the specified frequency received via a communication line, and a means for detecting a calling signal of the specified frequency received via a communication line. The apparatus includes a return switch that sends the detected calling signal back to the monitoring station via a communication line when the calling signal is detected and the monitoring item signal indicates that there is no abnormality.

[Function] According to the present invention, when a calling signal of a specified frequency from a monitoring station is detected, and if the monitored item is normal, a return switch is operated and the calling signal is sent back to the monitoring station as a response signal at the same frequency. , If an abnormality occurs in a monitored item, there is no response. .

Therefore, the monitoring station can determine the state of the monitored station based on the presence or absence of the response signal. According to the present invention, the monitored station only has to perform the operation of sending back a paging signal depending on the status of the monitored item. Compared to this, the configuration is much simpler and the power consumption can be reduced.

[Example] Next, an example of the present invention will be specifically described with reference to the attached drawings.

FIG. 1 is a diagram showing the configuration of a supervisory control system according to an embodiment of the present invention. A monitoring station monitoring control device 1 provided in a monitoring station and a monitored station monitoring control device 2 provided in each of a plurality of monitored stations can transmit and receive data in both directions via an uplink transmission channel 3 and a downlink transmission channel 4. is combined with

The monitoring station monitoring control device 1 includes a monitoring station logic circuit 11, a specified frequency oscillation circuit 12, and a specified frequency detection circuit 13. The monitoring station logic circuit 11 provides a signal specifying the specified frequency assigned to the monitored station to be monitored to the specified frequency oscillation circuit 12, and also provides the specified frequency detection circuit 1
The state of the monitored station is determined by introducing the detection result of step 3. The specified frequency oscillation circuit 12 generates a calling signal of the specified frequency specified by the monitoring station logic circuit 11 and sends it to the uplink transmission channel 3. The specified frequency detection circuit 13 detects a response signal of the specified frequency sent back from the monitored station monitoring and control device 2 via the downlink transmission channel 4.

The monitored station monitoring control device 2 also includes a specified frequency detection circuit 21, a monitoring item signal generation circuit 22, and an AND gate 23.
and a return switch 24. The specified frequency detection circuit 21 detects a calling signal of a specified frequency assigned to its own station. The monitoring item signal generation circuit 22 is a signal that indicates the presence or absence of an abnormality in the monitoring item.If the monitoring item is normal, it displays "i", and if the monitoring item has an abnormality, it displays "0". If the frequency is detected and there is no abnormality in the monitored items, outputs "1",
In other cases, "0" is output.Return switch...l
When the output of the AND gate 23 becomes "'1", the circuit 24 turns on and returns the paging signal of the specified frequency detected on the upstream transmission channel 3 to the downstream transmission channel 4.

Next, the operation of the supervisory control system configured as described above will be explained.

Different specified frequencies are assigned to the plurality of monitored stations. When checking the status of one of them, the monitoring station logic circuit 11 first instructs the specified frequency oscillation circuit 12 about the monitored station or its specified frequency. In response to this instruction, the specified frequency oscillation circuit 12 sends out a paging signal of the specified frequency to the uplink transmission channel 3.

When the specified frequency detection circuit 21 of the monitored station monitoring and control device 2 detects the specified frequency assigned to its own station, the output of the detection circuit 21 becomes "1" and is applied to one side of the AND gate 23. At this time, if there is no abnormality in the monitored item, "1"' is also applied to the other input of the AND gate 23. Therefore, the output of the AND gate 23 also becomes 111 I+, and the folding switch 24 is driven and turned on.

Thereby, the detected signal of the specified frequency is sent back to the monitoring station side via the downlink transmission channel 4. In the monitoring station monitoring control device 1, the specified frequency detection circuit 13 detects the signal of the specified frequency (response signal) sent back, and recognizes that the monitoring items of the monitored station are normal. However, if that frequency is not returned within a certain period of time, it is recognized that an abnormality has occurred in the monitored station.

As described above, according to the system of the present embodiment, a return switch 24 is provided in each monitored station monitoring and control device 2, and a method is adopted in which only the detected calling signal of the specified frequency is sent back, so that a large amount of power is required. It is easy to configure and does not require

Note that the present invention can utilize either a wired or wireless communication system. In these systems,
The two channels, uplink and downlink, may be secured physically or by time division. For example, in a wireless system, it is possible to secure two channels by delaying the response signal to the calling system. In this case, a delay line may be used as a line connecting the input terminal of the specified frequency detection circuit 21 and the input terminal of the return switch 24.

[Effects of the Invention] As explained above, the present invention provides a return switch in the monitored station, and when a calling signal of a specified frequency is detected,
Since the system simply sends back the call signal only when the monitored item is normal, it does not require a large amount of power and has the advantage of being simple in configuration.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a supervisory control system according to an embodiment of the present invention. 1; Monitoring control device for monitoring station, 2; Monitoring control device for monitored station, 3; Uplink transmission channel, 4: Downlink transmission channel, 1
1; Monitoring station logic circuit, 12; Specified frequency oscillation circuit, 1
3,21. Specified frequency detection circuit, 22: Monitored item signal generation circuit, 23; AND gate, 24; Return switch

Claims (1)

[Claims] (1) The monitoring station monitoring and controlling device is composed of a monitoring and controlling device for a monitoring station provided in a monitoring station, a monitoring and controlling device for a monitored station provided in a monitored station, and a communication line connecting these. means for transmitting a paging signal of a specified frequency assigned to the monitored station to be monitored to the monitored station via the communication line, and the paging signal sent by this means is a response signal from the monitored station. and means for determining the state of the monitored station based on whether or not the response signal is detected by the means, the monitored station monitoring and control device comprising: means for outputting a monitoring item signal indicating the presence or absence of an abnormality in the monitoring item; means for detecting a calling signal of a prescribed frequency assigned to itself received via a communication line; A supervisory control system comprising: a return switch that returns the detected call signal to a communication line as a response signal when the monitored item signal indicates that there is no abnormality in the monitored item.