JPH03212099A - Wired-line data collection system - Google Patents

Abstract

PURPOSE:To improve redundancy and reliability by providing a bypass line to each transmission terminal station equipment when the transmission terminal station equipment arranged to plural points and a reception terminal station equipment arranged to other point are connected in cascade with one transmission line. CONSTITUTION:When a data signal processing circuit 7 is inactive, a switching command signal by modulation of a power supply current is inputted to a command signal reception circuit 12 through a signal line 13 with a command from a reception terminal station equipment 3, a switching control circuit 10 is driven and a bypass switching signal is outputted to signal lines 11a, 11b. When bypass changeover switches 61, 62 are operated, main data signal lines 141, 142 are switched into a bypass signal line 9, a repeater circuit 5 and a receiver circuit 8 are connected directly to bypass the data signal processing circuit 7 being the inactivated circuit and the data sent from a preceding point is outputted from a driver circuit 8. Thus, the interruption of the data at the preceding transmission terminal equipment is avoided even by the inactivated data processing unit.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a collection system for various measurement data, and in particular, it converts measurement data obtained at multiple points into digital signals and continuously transmits them via a transmission line. Regarding the system of collection.

(Prior Art) The configuration of a conventional wired data collection system and the block configuration of a transmitting terminal device are shown in FIGS. 2 and 3, respectively. In Figure 2, 11 to 13 are rL-ff7'
L is a transmitting end station device, and 3 is a receiving end station device. In FIG. 3, 5 is a repeater circuit, 7 is a data signal processing circuit, and 8 is a repeater circuit.
is the driver circuit.

As a conventional technique, a plurality of transmitting terminal devices 11 to 13
and one receiving terminal device 3 are connected to one transmission line 21 to 24.
A cascaded configuration was adopted. Further, the transmitting terminal equipment [11-13] includes a repeater circuit 5 that receives and reproduces a signal sent via the transmission path 4 from the location where it is placed;
It is composed of a data signal processing circuit 7 for measuring information in the natural world, converting it into a signal, and performing multiplexing processing, and a driver circuit 8 for transmitting the processed signal.
was.

(Problems to be Solved by the Invention) In the conventional data collection system described above, when the data processing circuit in one transmitting terminal station device becomes inoperable, data is disconnected from all preceding transmitting terminal station devices. andQ
) There are 5 drawbacks.

An object of the present invention is to provide a bypass path for each transmitting terminal station when cascading a transmission line between a transmitting terminal station installed at a plurality of points and a receiving terminal station installed at other points. To provide a wired data acquisition system which overcomes the above disadvantages by providing a wired data acquisition system configured so that data will not be cut off at the transmitting terminal station provided even if the data processing device is inoperable. It is in.

(Means for Solving the Problems) The wired data collection system according to the present invention includes a plurality of transmitting end station devices and one receiving end station device, and connects the transmitting end station devices and the receiving end device to one line. They are configured by cascade-connecting them through transmission lines.

In the above configuration, each transmitting terminal device includes a data signal processing circuit, a repeater circuit, a driver circuit, a pair of bypass changeover switches, and a changeover control circuit.

The data signal processing circuit is a circuit that measures information, converts it into a signal, and multiplexes it.

The repeater circuit is for receiving and reproducing signals that are input from a pre-installed station via a transmission line.

The driver circuit is for transmitting the regenerated signal.

The bypass changeover switch -n is for switching to a bypass signal line that directly connects the repeater circuit and the driver circuit when the data signal processing circuit malfunctions and becomes inoperable.

The switching control circuit is for controlling the pair of bypass switching switches.

(Example) Next, the invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a transmitting terminal device in a wired data collection system according to the invention.

In FIG. 1, 5 is a repeater circuit, 61° 62) is a bypass changeover switch, 7 is a data signal processing circuit, 8 is a driver circuit, 10 is a switching control circuit, and 12 is a command signal receiving circuit.

In FIG. 1, when the data signal processing circuit 7 becomes inoperable for some reason, a switching command signal by modulating the power supply current is sent from the old Iwao 13 to the command signal receiving circuit 12 in response to a command from the receiving terminal device 3. It takes human power. By kneading 9
) When the switching weight control circuit 10 is driven, a bypass switching signal is output on the signals 11i111a and llb. When the bypass changeover switches 61 and 62 are activated by the bypass changeover signal, the main data signals @141 and 142 are switched to the bypass signal line 9.The repeater circuit 5 and receiver circuit 8 are directly connected, and the data signal processing circuit in the inactive part The data sent from the preceding point, bypassing 7, is output from the driver circuit 8.

(Effects of the Invention) As explained above, the present invention provides a method for cascading transmission terminal equipment located at multiple locations and receiving equipment located at other locations using a single transmission line. Providing a bypass path to the transmitting terminal device has the effect of improving redundancy and reliability in a supplementary manner.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a transmitting terminal device in a wired data collection system according to the present invention. FIG. 2 is a block diagram showing a wired data collection system in which a plurality of transmitting terminal devices and one receiving terminal device are connected in cascade through one transmission line. FIG. 3 is a block diagram showing an example of a transmitting terminal device according to the prior art. 11-13... Transmission terminal equipment 21-24... Transmission line 3... Receiving station cover 5-- Repeater circuit 61.62-- Bypass changeover switch 7... Data signal processing circuit 8-.-Driver circuit 10...Switching control circuit 12...Command signal receiving circuit 4.9. lla, llb, 13, 15, 141.142
···Signal line

Claims (1)

[Claims] Equipped with multiple transmitting end station devices and one receiving end station device,
A wired data collection system configured by cascading the transmitting end station device and the previous receiving end station device through a single transmission line, wherein each transmitting end station device measures information, converts it into a signal, and multiplexes the information. a data signal processing circuit for receiving and reproducing a signal sent from a predetermined point via the transmission path, and a driver circuit for transmitting the reproduced signal. a pair of bypass changeover switches for switching to a bypass signal line that directly connects the repeater circuit and the driver circuit when the data signal processing circuit malfunctions or becomes inoperable; and a pair of bypass changeover switches for controlling the pair of bypass changeover switches. What is claimed is: 1. A wired data collection system comprising a switching control circuit for