JPH04111630A - Data transmission system - Google Patents

Abstract

PURPOSE:To ensure the changeover from a system with a fault caused therein to a standby system by disconnecting a data transmitter through an input/output optical fiber cable in a prescribed time after a power supply is interrupted. CONSTITUTION:When a power supply 13 of an active system is interrupted, a voltage detection circuit 14 sends an earthing signal to a timer relay 15 and it is operative after a prescribed time. When the relay 15 is active, its contact 18 is opened after it is closed, an optical switch 11 is disconnected from a battery 17 and power supply is terminated. A fault such as out of synchronism caused in a transmission line for the prescribed time is detected by other data transmitter of the active system and the changeover to the standby system is implemented. Then the system changeover at interruption of power supply is ensured by selecting a time constant of the timer relay to be a time or over when other data transmitter of one system detects a fault such as out of synchronism caused in the transmission line after the power supply of one system is interrupted and the changeover to the other system is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data transmission system that is inserted into and connected to an optical loop type transmission line.

[Prior Art] Conventionally, a system has been developed in which multiple data transmission systems, which are duplexed in a working system and a standby system, are connected in a loop using a duplexed optical fiber cable, and the data transmission systems of the working system are connected in a loop. data transmission.

When the active system fails, the standby data transmission system is configured to perform data transmission using a system connected in a loop, and when a power failure occurs in each data transmission system.

By controlling the optical switch to disconnect the data transmission equipment in each data transmission system from the destination fiber cable and connect the optical fiber cables.

A transmission system that prevents a loop-shaped transmission line from being cut is known.

FIG. 2 shows an example of the configuration of a conventional data transmission system.

In FIG. 2, 10 is a current data transmission system, and 20 is a backup data transmission system. Data transmission system 10 (or 2
0), when the output (main DC power) of the 1 main power supply 13 (or 23) is cut off, the optical switch 11 (or 21
) is also disconnected at the same time, and as a result, the optical switch 11 (or 21) or the data transmission device 1
2 (or 22) input and output ends as input and output optical fibers!・Separate from the cable and connect directly between the input and output optical fiber cables.

[Problem to be solved by the invention] In the conventional transmission system described above, when the power to one data transmission system of one piece system is cut off, the power supplied to the data transmission device is cut off, and the optical switch is interrupted. Since the supplied power is also cut off at the same time, the optical switch disconnects the data transmission equipment and the power supply before the other data transmission systems can detect abnormalities such as loss of synchronization that occur in the transmission line due to the power cut. To be able to do it.

There is a drawback that one system becomes normal and switching to the other system is not performed, and terminals connected to the data transmission device whose power has been cut off are unable to communicate.

An object of the present invention is to provide a data transmission system in which a data transmission device is disconnected from an input/output optical fiber cable after a predetermined period of time after power is turned off.

[Means for Solving the Problems] According to the present invention, a main power source that generates main DC power, a backup power source that generates backup DC power, and a main power source that is connected to the main power source and receives the main DC power. The data transmission device is connected to the backup power source and is in an operational state during the period of time, and the input end and the output end of the data transmission device are connected to the input side and output side optical fiber cables while the data transmission device is connected to the backup power source and receiving the backup DC power. However, when the bank-up DC power is not being received, the input end and the output end of the data transmission device are disconnected from the input side and the output side optical fiber cables, and the input side and the output side optical fiber cables are connected to each other. and an optical switch that connects directly between the main power source and the main power source.

a detection means for detecting that the supply of the main DC power has been stopped and outputting earth air; - A relay element that changes from a non-operating state to an active state by pump DC power is connected between the backup power source and the optical switch, and when the relay element is in the non-operating state, the relay element changes from a non-operating state to an active state by the pump DC power, and when the relay element is in the non-operating state, There is obtained a data transmission system characterized in that it has a contact point that disconnects the backup power source and the first switch when the relay element is in the operating state.

[Example] Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, in a data transmission system 2 according to an embodiment of the present invention, for example, a working system 10, an output line of a power supply 13 is branched into two lines, one of which is connected to a data transmission device 12. . The other wire is further branched into two wires, one of which is connected to a timer relay 15 via a voltage detection circuit 14.
The other side is connected to a backup battery 17 via a backflow prevention diode 16.

This battery 17 is charged by the main power of the main power source 13 via the reverse current prevention diode 16, so the battery 17 generates the same DC voltage value as the main power source 13. This battery 17 is connected to the optical switch 11 via a contact 18 of a timer relay 15.

Note that the standby system also has the same configuration as the optical switch 21. Pig transmission device 22. Main power supply 23. Voltage detection circuit 24, reverse current prevention diode 26. It has a timer relay 27 and its contacts 28.

For example, when the current power supply 13 is turned off, the voltage detection circuit 14 sends earth air to the timer relay 15, and the timer relay 15 becomes operational with a predetermined time constant (that is, after a predetermined time).

When the timer relay 15 is activated, its contact 18
changes from the on state shown in the figure to the off state, and the optical switch 11
is disconnected from battery 17.

Power supply by the battery 17 ends. During the second predetermined period of time, another data transmission device in the active system detects an abnormality such as loss of synchronization occurring in the transmission path.

Switching to the standby system is performed.

Here, the time constant of the timer relay is set to detect abnormalities such as loss of synchronization that occur in the transmission path after the power of one system is cut off, and to detect abnormalities such as loss of synchronization that occur in the transmission path and transmit the time constant to the other data transmission device. By selecting a time that is longer than the time required to complete switching, system switching can be reliably performed when the power is turned off.

As described above, according to this embodiment, when the power of one system is turned off, the optical switch is backed up by a battery, and an abnormality such as an out-of-synchronization that occurs in the transmission path can be detected by the data transmission of other systems in the same system. Since the system reliably detects the error, the system in which the abnormality has occurred can be switched to the standby system without fail.

[Effects of the Invention] As described above, according to the present invention, a data transmission system is obtained in which a data transmission device is disconnected from an input/output optical fiber cable after a predetermined period of time after power is cut off.

[Brief explanation of the drawing]

Figure i1 is a block diagram of an embodiment of the present invention, and Figure 2 is a block diagram of a conventional embodiment. 10... Current data transmission system 20... Backup pig transmission system, 11 and 21... Optical switch, 12 and 22...
・Data transmission equipment, 13 and 23...main power supply. U4 and 24...voltage detection circuit, 15 and 25 river timer relay, 16 and 26...backflow prevention diode,
17 and 27... battery, 18 and 28... timer relay contact. U Figure 1

Claims (1)

[Claims] 1. A main power source that generates main DC power, a backup power source that generates backup DC power, and is connected to the main power source and becomes operational while receiving the main DC power. While the data transmission device is connected to the backup power source and receives the backup DC power, the input and output ends of the data transmission device are connected to the input and output optical fiber cables, and the backup DC power is supplied to the data transmission device. an optical switch that disconnects the input end and the output end of the data transmission device from the input side and the output side optical fiber cable when the data transmission device is not receiving data, and directly connects the input side and the output side optical fiber cable; a detection means that is connected to the main power source and outputs earth air upon detecting that the supply of the main DC power has been stopped; and a detection means that is connected to the detection means and the backup power source and receives the earth air; A relay element is connected between the backup power source and the optical switch, and when the relay element is in the non-operating state, the relay element changes from the non-operating state to the operating state by the backup DC power, A data transmission system comprising: a contact that connects a power source and the optical switch and disconnects the backup power source and the optical switch when the relay element enters the operating state. . 2. The main power source generates the product of a predetermined voltage value and a predetermined current value as the main DC power, and the backup power source also generates the product of the predetermined voltage value and the predetermined current value. The detection means outputs the main DC power as it is to the relay element when receiving the main DC power, and for the predetermined period of time, the detection means outputs the main DC power as it is to the relay element. 2. The data transmission system according to claim 1, wherein the data transmission system is determined by a time constant of a time constant circuit provided in the element.