JP2013207474A - Monitoring system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To get information to bypass by control of a neighboring monitoring device.SOLUTION: A monitoring system comprises: a plurality of monitoring devices 100 connected in a daisy chain; and a control device 300 which transmits control information to the plurality of monitoring devices 100 and also receives monitoring information obtained by each of the plurality of monitoring devices. A monitoring device 100 includes: a first communication unit 112 for communicating with an upstream monitoring device 100; a second communication unit 114 for communicating with a downstream monitoring device 100, and also comprises: a relay unit 110 for relaying the control information and the monitoring information communicated between the upstream monitoring device 100 and the downstream monitoring device 100 via the first communication unit 112 and the second communication unit 114; and a bypass unit 120 which gets the control information to bypass to the downstream monitoring device 100 and gets the monitoring information to bypass to the upstream monitoring device 100 by the control of the upstream monitoring device 100.

Description

  The present invention relates to a monitoring system including a plurality of monitoring devices and a control device that controls the monitoring devices.

  There has been proposed a surveillance system that monitors the state of an elongated area such as a station platform by using a plurality of surveillance cameras connected in a daisy chain. For example, a plurality of monitoring cameras are installed along a platform of a station, and monitoring information acquired by each monitoring camera is transmitted to a server via a plurality of monitoring cameras connected in a daisy chain (for example, patent documents) 1).

  In addition, a plurality of sensors that monitor road conditions along a plurality of street lights arranged on a sidewalk are provided, and an optical sensor that transmits monitoring information acquired by the sensors to a gateway by performing optical communication between the plurality of sensors. A network system is also disclosed. In this system, a group of sensors connected in a daisy chain are provided in two rows of street lamps arranged on both sides of the road, and when one sensor fails, it is monitored by another row of sensors. Information is bypassed (see, for example, Patent Document 2).

JP 2012-11989 JP 2005-124123 A

  When one of a plurality of monitoring cameras connected in a daisy chain fails, monitoring information cannot be transmitted, and it is necessary to promptly repair or replace the failed monitoring camera. However, it is difficult to quickly replace or repair surveillance cameras installed in public places such as station platforms, roads or tunnels. Therefore, even if one of the monitoring cameras breaks down, it is required to transmit the monitoring information acquired by another monitoring camera.

  As in the conventional configuration, by providing two sensor rows to make a detour when a failure occurs, the monitoring information can be transmitted without going through the failed sensor. However, in order to bypass the failed sensor, it is necessary to switch the direction of the optical communication unit of the sensor on both sides of the failed sensor. In addition, there is a problem that the cost increases when two rows of sensor groups are provided.

  Accordingly, the present invention has been made in view of these points, and provides a monitoring system that can quickly bypass a failed monitoring device among a plurality of monitoring devices connected in a daisy chain and transmit monitoring information. Objective.

  In the present invention, a monitoring system comprising: a plurality of monitoring devices connected in a daisy chain; and a control device that transmits control information to the plurality of monitoring devices and receives monitoring information acquired by each of the plurality of monitoring devices. provide. Each of the monitoring devices in the monitoring system includes a first communication unit that communicates with an upstream monitoring device located upstream of the daisy chain connection with respect to the monitoring device, and a downstream that is located downstream of the daisy chain connection with respect to the monitoring device. A relay unit that relays control information and monitoring information communicated between the upstream monitoring device and the downstream monitoring device via the first communication unit and the second communication unit. Have.

  Each of the monitoring devices includes a detour unit that bypasses the control information to the downstream monitoring device and detours the monitoring information to the upstream monitoring device by the control of the control device via the upstream monitoring device or the downstream monitoring device, and a relay unit. And a signal generation unit that generates a detour signal for controlling the detour unit of the downstream monitoring device in accordance with the control information received from the control device.

  The monitoring device may further include an external power supply unit that supplies power to the downstream monitoring device and starts supplying power to the downstream monitoring device in synchronization with a change in the detour signal generated by the signal generation unit. Good. The monitoring device may further include a selection unit that selects whether to output the detour signal generated by the signal generation unit or the detour signal generated by the upstream monitoring device to the downstream monitoring device. .

  The detour unit of the monitoring device detours the control information and the monitoring information according to the change in the logical value of the detour signal generated by the upstream monitoring device, and the selection unit sets the logical value of the detour signal generated by the upstream monitoring device. A bypass signal generated by the upstream monitoring device may be selected according to the change.

  The monitoring apparatus further includes an internal power supply unit that generates power for operating the relay unit, and a power supply switching unit that switches whether to supply the power generated by the internal power supply unit to the relay unit according to a detour signal You may have.

  If the control device does not receive response information to the control information transmitted to the downstream monitoring device within a predetermined time, the control device retransmits the control information to the downstream monitoring device after setting the detour unit of the monitoring device to the detour state, If the response information for the received control information is received within a predetermined time, it is determined that the monitoring device has failed. If the response information for the retransmitted control information is not received within the predetermined time, it is determined that the downstream monitoring device has failed. May be.

  According to the present invention, there is an effect that monitoring information can be transmitted by quickly bypassing a failed monitoring device among a plurality of monitoring devices connected in a daisy chain.

1 shows a configuration of a monitoring system according to a first embodiment. The monitoring system of 1st Embodiment shows an example of a usage condition. The structure of the monitoring apparatus of 1st Embodiment is shown. The communication sequence in the monitoring system of 1st Embodiment is shown. The structure of the monitoring apparatus of 2nd Embodiment is shown. The structure of the monitoring apparatus of 3rd Embodiment is shown. The operation timing of the selection part in 3rd Embodiment is shown. The operation | movement flow of the control apparatus which detects the failure of the monitoring apparatus of 4th Embodiment is shown. The communication sequence in the monitoring system of 4th Embodiment is shown. The structure of the monitoring apparatus of 5th Embodiment is shown. The structure of the detour signal selection part of 5th Embodiment and the relationship between a detour signal selection part and a detour part are shown. The structure of the monitoring apparatus of 6th Embodiment is shown. The operation | movement flowchart of the control apparatus in 6th Embodiment is shown. The structure of the monitoring apparatus of 7th Embodiment is shown. The communication sequence in the monitoring system of 7th Embodiment is shown. The communication sequence in case the some adjacent monitoring apparatus has failed is shown. The communication sequence in case the some adjacent monitoring apparatus has failed is shown. The structure of the monitoring apparatus of 8th Embodiment is shown. The structure of the monitoring system of 9th Embodiment is shown.

<First Embodiment>
[Basic configuration of the monitoring system]
FIG. 1 shows a configuration of a monitoring system 10 according to the first embodiment. FIG. 2 shows an example of how the monitoring system 10 according to the first embodiment is used. The monitoring system 10 includes a plurality of monitoring devices 100 (monitoring device 100-1, monitoring device 100-2, ..., monitoring device 100-n, where n is a natural number of 3 or more) connected in a daisy chain, The control apparatus 300 connected with the monitoring apparatus 100 is provided. A plurality of monitoring devices 100 are connected by a communication line 50. The communication line 50 is an 8-core cable for LAN (local area network), for example.

  The monitoring system 10 may include a hub 400 between the control device 300 and the monitoring device 100-1. The monitoring system 10 may include a plurality of groups of monitoring devices 100 connected to the hub 400. The monitoring system 10 may include a monitor 500 that displays the monitoring information acquired from the monitoring device 100 by the control device 300. Here, the monitoring information is image information or video information of the peripheral area around the place where the monitoring apparatus 100 is installed, or information indicating the state of the peripheral area of the monitoring apparatus 100.

  Each of the plurality of monitoring devices 100 acquires monitoring information and transmits it to the control device 300. The control device 300 transmits control information to the plurality of monitoring devices 100 and receives monitoring information acquired by each of the plurality of monitoring devices 100. For example, the monitoring device 100 includes a camera that acquires an image or video of the peripheral region of the monitoring device 100 or a sensor that detects the state of the peripheral region of the monitoring device 100. The monitoring device 100 may generate a file in which the acquired monitoring information is compressed and transmit the file to the control device 300.

  As an example, the monitoring system 10 is installed in a tunnel, and the plurality of monitoring devices 100 transmit an image or video of a vehicle passing through the tunnel to the control device 300 as monitoring information. The plurality of monitoring devices 100 may be installed on a platform of a station, and may transmit an image or video obtained by photographing a train or a passenger to the control device 300 as monitoring information. The plurality of monitoring devices 100 may include sensors, and may transmit monitoring information indicating the status of the place where the monitoring device 100 is installed, such as temperature, flame, and brightness, to the control device 300. The monitoring device 100 may transmit image information, video information, character information, or numerical information to the control device 300.

  Each of the plurality of monitoring devices 100 is connected to two adjacent monitoring devices 100. Specifically, the monitoring device 100-1 is connected to the control device 300 via the hub 400 and is connected to the monitoring device 100-2. The monitoring device 100-2 is connected to the monitoring device 100-1 and the monitoring device 100-3. Each monitoring device 100 is installed 10 m apart, for example. The plurality of monitoring devices 100 may be operated by receiving power from an AC power supply, or may be operated by a built-in battery.

  Each monitoring device 100 amplifies or shapes the signal received from the adjacent monitoring device 100 and transmits the amplified signal to the monitoring device 100 adjacent to the opposite side of the monitoring device 100 that has received the signal. Therefore, in the monitoring system 10, by increasing the number of monitoring devices 100 to be connected, signals are transmitted over a section of an arbitrary length between the monitoring device 100 and the control device 300 without deteriorating the signals. Can do.

  The control device 300 transmits control information including identification information corresponding to at least one monitoring device 100 among the plurality of monitoring devices 100. When receiving the control information including the identification information of the own device, the monitoring device 100 transmits the monitoring information to the control device 300 according to the received control information. When the monitoring apparatus 100 receives control information that does not include the identification information of the own apparatus, the monitoring apparatus 100 transmits the received control information to the adjacent monitoring apparatus 100.

  In the present specification, the first side centering on one monitoring device 100 among the plurality of monitoring devices 100 connected in a daisy chain is referred to as upstream, and the second side opposite to the first side is referred to as upstream. Called downstream. A monitoring device 100 adjacent to one monitoring device 100 among the plurality of monitoring devices 100 is referred to as an upstream monitoring device 100 and a downstream monitoring device 100.

  For example, the upstream monitoring device 100 is the monitoring device 100-1 adjacent to the control device 300 side in the daisy chain connection with respect to the monitoring device 100-2. The downstream monitoring device 100 is a monitoring device 100-3 adjacent to the monitoring device 100 on the side opposite to the upstream monitoring device 100 with respect to the monitoring device 100-2. The upstream monitoring device 100 may be the monitoring device 100-3, and the downstream monitoring device 100 may be the monitoring device 100-1.

[Basic configuration of monitoring apparatus 100]
FIG. 3 shows a configuration of the monitoring apparatus 100 according to the first embodiment. The monitoring apparatus 100 includes a relay unit 110, a bypass unit 120, a monitoring unit 130, a control unit 140, a connection unit 150, a connection unit 152, and a signal generation unit 160.

  The connection unit 150 is a connector connected to the upstream monitoring device 100. The connection unit 152 is a connector connected to the downstream monitoring device 100. The connection unit 150 and the connection unit 152 are, for example, 8-core modular connectors for LAN (local area network).

  Between the connection unit 150 and the upstream monitoring device 100, two transmission lines for transmitting control information, two transmission lines for transmitting monitoring information, and one control line for transmitting a detour signal for controlling the detour unit 120 And a cable including a power supply line and a ground line for supplying power for operating the bypass unit 120.

  The monitoring unit 130 is a camera or a sensor, for example. The control unit 140 operates the monitoring unit 130 based on the control information received from the control device 300 via the upstream monitoring device 100, and acquires monitoring data including image data or detection data generated by the monitoring unit 130. The monitoring information including the monitoring data is generated and transmitted to the control device 300. The control unit 140 may generate an Ethernet (registered trademark) data packet including monitoring information and transmit the data packet to the control device 300 via the upstream monitoring device 100.

  The relay unit 110 communicates with the upstream monitoring device 100 positioned upstream of the daisy chain connection with respect to the monitoring device 100, and the downstream monitoring device positioned downstream of the daisy chain connection with respect to the monitoring device 100. And a second communication unit 114 that communicates with 100. The relay unit 110 may include three or more communication units. The relay unit 110 relays control information and monitoring information communicated between the upstream monitoring device 100 and the downstream monitoring device 100 via the first communication unit 112 and the second communication unit 114. The relay unit 110 has a hub for Ethernet (registered trademark), for example.

  The relay unit 110 includes identification information of the monitoring device 100, identification information of the plurality of monitoring devices 100 or the control devices 300 installed upstream of the monitoring device 100, and a plurality of monitoring devices installed downstream of the monitoring device 100. The identification information of the device 100 is stored. The relay unit 110 stores identification information of a plurality of monitoring devices 100 installed upstream of the monitoring device 100 in association with the first communication unit 112, and a plurality of monitoring devices installed downstream of the monitoring device 100. 100 pieces of identification information may be stored in association with the second communication unit 114. The identification information is, for example, a MAC address or an IP address.

  The relay unit 110 determines how to process the control information according to the identification information included in the received control information. For example, when the control information includes the identification information of the monitoring device 100, the relay unit 110 inputs the received control information to the control unit 140 of the monitoring device 100. When the received control information includes the identification information of the monitoring device 100 installed downstream, the relay unit 110 transmits the control information to the downstream monitoring device 100 via the second communication unit 114. When the monitoring information received from the downstream monitoring device 100 includes the identification information of the control device 300, the relay unit 110 transmits the monitoring information to the upstream monitoring device 100 via the first communication unit 112.

  The bypass unit 120 causes the downstream monitoring device 100 to bypass and receive the control information received from the upstream monitoring device 100 under the control of the control device 300 via the upstream monitoring device 100 or the downstream monitoring device 100. The monitored information is detoured to the upstream monitoring device 100. For example, the upstream monitoring device 100 controls the bypass unit 120 based on the control information received from the control device 300. The downstream monitoring device 100 may control the bypass unit 120 based on the control information received from the control device 300.

  The bypass unit 120 is, for example, a relay that is controlled by a bypass signal output from the upstream monitoring device 100. The bypass unit 120 is preferably a mechanical relay whose electrical characteristics are difficult to change even when it is not used for a long period of time. As an example, the bypass unit 120 is driven by power supplied from the power supply of the upstream monitoring device 100.

  In a normal use state, the bypass unit 120 connects the connection unit 150 and the first communication unit 112, and connects the connection unit 152 and the second communication unit 114. The detour unit 120 is connected between the connection unit 150 and the first communication unit 112 and the connection between the connection unit 152 and the second communication unit 114 in accordance with a change in the detour signal from the upstream monitoring device 100. Is disconnected, and the connecting portion 150 and the connecting portion 152 are connected. In this bypass state, the control information transmitted by the control device 300 is transmitted to the downstream monitoring device 100 via the upstream monitoring device 100, the connection unit 150, the bypass unit 120, and the connection unit 152. The monitoring information transmitted by the downstream monitoring device 100 is transmitted to the control device 300 via the connection unit 152, the bypass unit 120, the connection unit 150, and the upstream monitoring device 100.

  The signal generation unit 160 generates a bypass signal (u1 signal in FIG. 3) for controlling the bypass unit 120 of the downstream monitoring device 100 in accordance with the control information received from the control device 300 via the relay unit 110. The detour unit 120 diverts the control information according to the detour signal (u2 signal in FIG. 3) generated by the signal generation unit 160 of the upstream monitoring apparatus 100. The monitoring device 100 may control the detour unit 120 of the upstream monitoring device 100 based on the detour signal generated by the signal generation unit 160. The bypass unit 120 may bypass the control information according to the bypass signal generated by the signal generation unit 160 of the downstream monitoring device 100.

  As an example, the signal generation unit 160 generates a bypass signal based on an instruction from the control unit 140 that has received control information from the control device 300. Specifically, when the control device 300 detects that the downstream monitoring device 100 is out of order, the control device 300 generates control information including an instruction to bypass the downstream monitoring device 100 with respect to the monitoring device 100. When the control unit 140 detects that the received control information includes an instruction to bypass the downstream monitoring device 100, the control unit 140 sets a logical value that causes the bypass unit 120 of the downstream monitoring device 100 to bypass the signal generation unit 160. Generate a detour signal.

  When detecting a failure of the downstream monitoring device 100, the control unit 140 may cause the signal generation unit 160 to generate a bypass signal without receiving control information from the control device 300. The control unit 140 may cause the signal generation unit 160 to generate a bypass signal in response to a user operation of the monitoring device 100.

  FIG. 4 shows a communication sequence among the control device 300, the upstream monitoring device 100, the monitoring device 100, and the downstream monitoring device 100 in the monitoring system 10 of the first embodiment. When the monitoring device 100 is out of order, the control device 300 cannot receive the monitoring information corresponding to the control information transmitted to the downstream monitoring device 100. In such a case, the control device 300 transmits control information including an instruction to place the monitoring device 100 in a detour state to the upstream monitoring device 100.

  When the upstream monitoring device 100 changes the logical value of the bypass signal in accordance with the control information received from the control device 300, the monitoring device 100 enters a bypass state. When the control device 300 transmits control information to the downstream monitoring device 100 after the monitoring device 100 enters a detour state, the monitoring information from the downstream monitoring device 100 bypasses the monitoring device 100 and passes through the upstream monitoring device 100. To reach the control device 300.

[Effect of the first embodiment]
As described above, according to the monitoring system 10 of this embodiment, when any one of the plurality of monitoring devices 100 fails, the upstream monitoring device 100 does not depend on the failed monitoring device 100. Control information and monitoring information can be bypassed by control. Therefore, even if the monitoring device 100 is out of order, the control device 300 has an effect that the control information can be transmitted to the downstream monitoring device 100 reliably and quickly and the monitoring information can be received.

<Second Embodiment>
[Having an external power supply unit 170 that supplies power to the downstream monitoring device 100]
FIG. 5 shows a configuration of the monitoring apparatus 100 according to the second embodiment. The monitoring apparatus 100 shown in the figure is different from the monitoring apparatus 100 shown in FIG. 3 in that it further includes an external power supply unit 170. Further, the detour unit 120 shown in the figure is driven by the power supply voltage Va input from the upstream monitoring device 100 via the connection unit 150.

  The external power supply unit 170 is an AC / DC converter that generates a DC voltage from an AC voltage supplied to the monitoring device 100, or a DC that generates a DC voltage of a different voltage based on the DC voltage generated by the AC / DC converter. / DC converter. The external power supply unit 170 may be an isolated power source in which an input and an output are insulated.

  The external power supply unit 170 supplies power to the downstream monitoring device 100. For example, the external power supply unit 170 supplies power for driving the bypass unit 120 of the downstream monitoring device 100. The external power supply unit 170 may start supplying power to the downstream monitoring device 100 in synchronization with a change in the detour signal from the upstream monitoring device 100.

  As an example, the signal generation unit 160 outputs a power supply control signal that switches whether to cause the external power supply unit 170 to output a voltage in accordance with an instruction from the control unit 140. The external power supply unit 170 switches whether to start power supply to the downstream monitoring device 100 according to the power supply control signal from the signal generation unit 160.

  When changing the logic value of the bypass signal and causing the bypass unit 120 of the downstream monitoring device 100 to bypass the control information, the signal generation unit 160 changes the power control signal and causes the external power supply unit 170 to start supplying power. . For example, the signal generation unit 160 changes the power control signal simultaneously with the bypass signal. The signal generator 160 may change the power control signal after changing the bypass signal, or may change the bypass signal after changing the power control signal.

[Effects of Second Embodiment]
As described above, according to the second embodiment, the external power supply unit 170 supplies power for operating the bypass unit 120 of the downstream monitoring device 100, so that the downstream monitoring device 100 is operating normally. In addition, the downstream monitoring device 100 is driven by driving the relay of the bypass unit 120 of the downstream monitoring device 100 without depending on the external power supply unit 170 of the monitoring device 100 when the downstream monitoring device 100 breaks down. 100 can bypass control information.

  In addition, when the bypass unit 120 of the monitoring device 100 is driven by the external power supply unit 170 of the upstream monitoring device 100 so that the bypass unit 120 enters a bypass state, the relay unit 110, the control unit 140, and the monitoring unit 130 The upstream monitoring device 100 can be insulated. As a result, there is an effect that the relay unit 110, the monitoring unit 130, and the control unit 140 can be exchanged even when the current flows through the bypass unit 120.

<Third Embodiment>
[Enable to bypass the two monitoring devices 100]
FIG. 6 shows a configuration of the monitoring apparatus 100 according to the third embodiment. The monitoring apparatus 100 shown in the figure is different from the monitoring apparatus 100 shown in FIG. 3 in that it further includes a selection unit 180, and is otherwise the same.

  The selection unit 180 selects whether to output the detour signal generated by the signal generation unit 160 of the monitoring device 100 or the detour signal generated by the upstream monitoring device 100 to the downstream monitoring device 100. The selection unit 180 selects the detour signal generated by the upstream monitoring device 100 when both the monitoring device 100 and the downstream monitoring device 100 are out of order. In other cases, the signal generation unit 160 of the monitoring device 100 selects the detour signal. Select the generated detour signal.

  When the bypass unit 120 in the monitoring device 100 is in a bypass state, the control unit 140 receives control information including an instruction to bypass the downstream monitoring device 100 from the control device 300 even if the downstream monitoring device 100 fails. I can't. Therefore, the control device 300 controls the selection unit 180 via the upstream monitoring device 100 to input a detour signal that makes the detour unit 120 of the monitoring device 100 a detour state also to the detour unit 120 of the downstream monitoring device 100. As a result, the bypass unit 120 of the downstream monitoring device 100 can be set to the bypass state. For example, the upstream monitoring device 100 inputs a selection signal for controlling the selection unit 180 to the selection unit 180 based on the control information received from the control device 300.

  The bypass unit 120 changes the connection state according to a change in the logical value of the bypass signal input from the upstream monitoring device 100 to bypass the control information and the monitoring information, and sets the logical value of the bypass signal after the change of the connection state. Regardless, the connection state after the change may be maintained. The bypass unit 120 includes, for example, a latching relay. The detour unit 120 may change the connection state according to a detour signal pulse input from the upstream monitoring device 100.

  The selection unit 180 includes a selection signal generation unit 182 and a signal selection unit 184. The selection unit 180 selects the bypass signal according to a change in the logical value of the bypass signal generated by the upstream monitoring apparatus 100. Specifically, the selection signal generation unit 182 bypasses the downstream monitoring device 100 generated by the signal generation unit 160 of the monitoring device 100 in accordance with a change in the logical value of the bypass signal generated by the upstream monitoring device 100. A selection signal that causes the signal selection unit 184 to select whether to output a signal or to output a bypass signal generated by the signal generation unit 160 of the upstream monitoring device 100 is generated.

  For example, the selection signal generation unit 182 generates the selection signal by delaying the bypass signal. Specifically, the selection signal generation unit 182 generates a selection signal whose logical value changes after a time longer than the pulse width of the bypass signal after the logical value of the bypass signal generated by the upstream monitoring apparatus 100 changes. To do. The signal selection unit 184 selects one from a plurality of bypass signals according to the selection signal generated by the selection signal generation unit 182 and outputs the selected one to the downstream monitoring device 100.

  Similarly, the selection unit 180 supplies power to the bypass unit 120 of the downstream monitoring device 100 from the external power supply unit 170 of the monitoring device 100 according to the logical value of the bypass signal generated by the upstream monitoring device 100. Alternatively, whether to supply power from the external power supply unit 170 of the upstream monitoring device 100 may be selected. When the selection unit 180 selects a power source that supplies power to the downstream monitoring device 100, power can be supplied from the normal upstream monitoring device 100 when the monitoring device 100 is out of order.

  FIG. 7 shows the operation timing of the selection unit 180 in the third embodiment. The signal generation unit 160 of the upstream monitoring device 100 changes the logical value of the bypass signal when the bypass unit 120 of the monitoring device 100 is set to the bypass state. In FIG. 7, the signal generation unit 160 of the upstream monitoring apparatus 100 changes the bypass signal from the positive logic value to the negative logic value, and then changes the negative logic value to the positive logic value.

  The detour unit 120 switches the connection at the timing (T1 in FIG. 7) when the detour signal changes from the positive logic value to the negative logic value, changes to the detour state, and maintains the changed state. The selection signal generation unit 182 changes the selection signal from the positive logic value to the negative logic value at a timing (T3) after the timing (T2) when the bypass signal changes from the negative logic value to the positive logic value. The signal selection unit 184 outputs a bypass signal from the upstream monitoring device 100 to the downstream monitoring device 100 in a state where the selection signal indicates a positive logic value (for example, T4). In this state, the bypass signal from the upstream monitoring device 100 indicates a positive logic value, so the downstream monitoring device 100 is not in the bypass state and operates normally.

  Here, when the control device 300 detects a failure of the downstream monitoring device 100, the control device 300 transmits control information including an instruction to place the downstream monitoring device 100 in a detour state to the upstream monitoring device 100. The signal generation unit 160 of the upstream monitoring device 100 changes the bypass signal from a positive logic value to a negative logic value (T5). The detour unit 120 of the downstream monitoring device 100 changes the detour unit 120 to the detour state according to the change of the detour signal input from the upstream monitoring device 100 from the positive logic value to the negative logic value, and maintains that state.

[Effect of the third embodiment]
As described above, according to the third embodiment, even when the monitoring device 100 downstream of the monitoring device 100 in the detour state has failed, the control device 300 performs control via the upstream monitoring device 100. By doing so, the monitoring apparatus 100 and the downstream monitoring apparatus 100 can be put into a detour state. Further, according to the configuration of the present embodiment, the monitoring device 100 and the downstream monitoring are performed using the detour signal generated by the upstream monitoring device 100 without increasing the number of signal lines between the monitoring device 100 and the upstream monitoring device 100. The effect that the apparatus 100 can be made into a detour state is also show | played.

<Fourth Embodiment>
[Failure detection using bypass unit 120]
FIG. 8 shows an operation flow of the control device 300 when a failure of the monitoring device 100 according to the fourth embodiment is detected. If the second communication unit 114 fails despite the first communication unit 112 in the monitoring device 100 operating normally, the control device 300 communicates control information with the control unit 140 of the monitoring device 100. Although the monitoring information can be transmitted and received, the control information may not reach the downstream monitoring device 100. Therefore, if the control device 300 cannot receive the monitoring information from the downstream monitoring device 100 according to the control information transmitted from the control device 300 to the downstream monitoring device 100, the possibility that the downstream monitoring device 100 has failed, and The second communication unit 114 of the monitoring apparatus 100 may be out of order.

  When the control device 300 cannot receive the monitoring information corresponding to the control information transmitted to the downstream monitoring device 100, the second communication unit 114 of the monitoring device 100 has failed or the downstream monitoring device 100 has failed. Can be determined by the following procedure.

  First, the control device 300 transmits control information to the downstream monitoring device 100 via the relay unit 110 (S102). When the monitoring information is normally received within a predetermined time according to the transmitted control information (S104), the control device 300 determines that the monitoring device 100 and the downstream monitoring device 100 are normal (S106).

  When the monitoring information corresponding to the transmitted control information is not received within a predetermined time (S104), the control device 300 causes the bypass unit 120 of the monitoring device 100 to be in a bypass state (S108). Subsequently, the control device 300 retransmits the control information for the downstream monitoring device 100 (S110). When receiving the monitoring information corresponding to the retransmitted control information within a predetermined time (S112), the control device 300 determines that the downstream monitoring device 100 is normal and the monitoring device 100 has failed (S114). ). When the monitoring information corresponding to the retransmitted control information is received within a predetermined time (S112), the control device 300 determines that the downstream monitoring device 100 is out of order (S116).

  FIG. 9 shows a communication sequence among the control device 300, the upstream monitoring device 100, the monitoring device 100, and the downstream monitoring device 100 in the monitoring system 10 according to the fourth embodiment. Since the control device 300 cannot receive the monitoring information corresponding to the control information transmitted to the downstream monitoring device 100, the control device 300 transmits control information including an instruction to place the monitoring device 100 in a detour state to the upstream monitoring device 100. The upstream monitoring device 100 changes the logical value of the bypass signal to place the bypass unit 120 of the monitoring device 100 in a bypass state.

  The control device 300 retransmits the control information for the downstream monitoring device 100 after setting the monitoring device 100 in a detour state. The control device 300 determines that the downstream monitoring device 100 is out of order if no monitoring information is received from the downstream monitoring device 100 even though the monitoring device 100 is in a detour state.

  When the control device 300 determines that the downstream monitoring device 100 has failed, the control device 300 transmits a control signal including an instruction to release the detour state of the monitoring device 100 to the upstream monitoring device 100. The monitoring device 100 releases the detour state in response to the detour signal from the upstream monitoring device 100. Subsequently, the control device 300 transmits a control signal including an instruction to place the downstream monitoring device 100 in a detour state to the monitoring device 100. The downstream monitoring device 100 enters a detour state according to the detour signal received from the monitoring device 100.

[Effect of the fourth embodiment]
As described above, by using the operation procedure of the fourth embodiment, the control device 300 controls the bypass unit 120 and retransmits the control information, so that the monitoring device 100 has failed or the downstream monitoring device 100 has It is possible to easily determine whether a failure has occurred.

<Fifth Embodiment>
[Bypass control by control of control unit 140]
FIG. 10 shows a configuration of the monitoring apparatus 100 according to the fifth embodiment. The monitoring apparatus 100 shown in the figure has a bypass signal selection unit 190 and differs from the monitoring apparatus 100 shown in FIG. 3 in that the control unit 140 generates a bypass signal that causes the bypass unit 120 to enter a bypass state. Are equivalent. The bypass signal selection unit 190 selects which of the bypass signal from the upstream monitoring device 100 and the bypass signal generated by the control unit 140 is input to the bypass unit 120.

  FIG. 11 shows the configuration of the detour signal selection unit 190 of the fifth embodiment and the relationship between the detour signal selection unit 190 and the detour unit 120. In FIG. 11, Va is a power supply voltage supplied from the external power supply unit 170 of the upstream monitoring device 100, and Vb is an internal power supply voltage of the monitoring device 100. The bypass signal selection unit 190 includes a photocoupler 192 and a photocoupler 194. The photocoupler 192 generates a signal that is electrically insulated from the bypass signal from the upstream monitoring device 100. The control unit 140 may monitor the state of the bypass unit 120 by acquiring the signal.

  The photocoupler 194 generates a signal that is electrically insulated from the bypass signal generated by the control unit 140. The signal is connected to a bypass signal from the upstream monitoring device 100 and an open drain connection or an open collector connection, and drives a relay included in the bypass unit 120. For example, in FIG. 11, when either the bypass signal from the upstream monitoring device 100 or the bypass signal from the control unit 140 changes to a negative logic value, the relay included in the bypass unit 120 operates to enter a bypass state.

[Effect of Fifth Embodiment]
As described above, according to the fifth embodiment, there is an abnormality in the communication line between the monitoring device 100 and the upstream monitoring device 100, and the monitoring device 100 cannot receive control information from the upstream monitoring device 100. Even in this case, the monitoring device 100 can place the downstream monitoring device 100 in a detour state.

<Sixth Embodiment>
[Monitoring Device 100 has Switching Unit 210]
FIG. 12 shows a configuration of the monitoring apparatus 100 according to the sixth embodiment. The monitoring apparatus 100 shown in the figure is different from the monitoring apparatus 100 shown in FIG. 3 in that a switching unit 210 is provided instead of the bypass unit 120, and is the same in other points. The switching unit 210 switches whether the control information is input to the first communication unit 112 or the second communication unit 114 under the control of the control device 300 via the upstream monitoring device 100 or the downstream monitoring device 100.

  Specifically, the switching unit 210 connects the first communication unit 112 to the upstream monitoring device 100 via the signal generation unit 160 in the first mode. In addition, the switching unit 210 connects the second communication unit 114 to the downstream monitoring device 100 via the connection unit 150. In this state, the first communication unit 112 can receive control information from the control device 300 via the upstream monitoring device 100, and the second communication unit 114 can receive monitoring information from the downstream monitoring device 100.

  In the second mode, the switching unit 210 disconnects the connection between the first communication unit 112 and the upstream monitoring device 100 and the connection between the second communication unit 114 and the downstream monitoring device 100, and the second communication unit 114. Is connected to the upstream monitoring apparatus 100. In this state, the second communication unit 114 can receive control information from the control device 300 via the upstream monitoring device 100.

  The signal generation unit 160 generates a switching signal (k1 in FIG. 12) for controlling the switching unit 210 included in the downstream monitoring device 100 according to the control information received from the control device via the relay unit 110. The switching unit 210 receives the control information received from the control device 300 via the upstream monitoring device 100 in accordance with the switching signal (k2 signal in FIG. 12) generated by the signal generation unit 160 of the upstream monitoring device 100. Whether to input to 112 or to the second communication unit 114 is switched. The monitoring device 100 may control the switching unit 210 of the upstream monitoring device 100 by a switching signal generated by the signal generation unit 160. The switching unit 210 may switch the input destination of the control information in accordance with the switching signal generated by the signal generation unit 160 of the downstream monitoring device 100.

  As an example, the signal generation unit 160 generates a switching signal based on an instruction from the control unit 140 that has received control information from the control device 300. Specifically, when the control device 300 needs to confirm whether or not the second communication unit 114 of the downstream monitoring device 100 is out of order, the control device 300 transmits the second communication of the downstream monitoring device 100 to the monitoring device 100. Control information including an instruction to switch the unit 114 to the second mode for connecting to the second communication unit 114 of the monitoring device 100 is generated. When the control unit 140 detects that the received control information includes an instruction to switch the switching unit 210 of the downstream monitoring device 100 to the second mode, the control unit 140 notifies the signal generation unit 160 of the switching unit 210 of the downstream monitoring device 100. A logical value switching signal is generated to switch the connection to the second mode.

[Determination Method for Switching Mode of Switching Unit 210]
FIG. 13 shows an operation flowchart of the control device 300 in the sixth embodiment. The control device 300 switches the switching unit 210 to transmit confirmation information for confirming the state of the monitoring device 100 to the monitoring device 100 via each of the first communication unit 112 and the second communication unit 114. Here, the confirmation information is control information used for confirming whether the monitoring apparatus 100 is operating normally.

  The control unit 140 generates response information to the control device according to the confirmation information received via the upstream monitoring device 100. The control device 300 determines that the monitoring device 100 has failed when the response information is not received from the first communication unit 112 or the second communication unit 114 within a predetermined time after transmitting the confirmation information.

  As an example, the control device 300 detects a failure by switching the mode of the switching unit 210 of the monitoring device 100 when the monitoring information is not received from the monitoring device 100 within a predetermined time after transmitting the control information to the monitoring device 100. To do. The control device 300 may detect a failure of the monitoring device 100 before a situation occurs in which the monitoring information cannot be received by periodically switching the mode of the switching unit 210 and transmitting the confirmation information. In order to prevent the load on the control unit 140 of the monitoring device 100 from becoming excessive, the control device 300 switches the mode of the switching unit 210 of the monitoring device 100 that has not transmitted the monitoring information and transmits the confirmation information, thereby It may be detected.

  Hereinafter, the operation of the control device 300 will be described with reference to FIG. First, the control device 300 transmits control information to the upstream monitoring device 100 to set the switching unit 210 to the first mode (S202). The control device 300 transmits the confirmation information to the monitoring device 100 with the switching unit 210 in the first mode (S204). The control device 300 determines that the first communication unit 112 is out of order when the response information is not received from the first communication unit 112 within a predetermined time after the confirmation information is transmitted to the monitoring device 100 (S206). (S208). For example, the control device 300 transmits the confirmation information in a state where the switching unit 210 is in the first mode, and then performs the first communication until the time corresponding to the distance between the control device 300 and the monitoring device 100 elapses. When the response information is not received via the unit 112, it is determined that the first communication unit 112 has failed.

  When receiving the response information within the predetermined time in S206, the control device 300 transmits the control information to the upstream monitoring device 100 and switches the switching unit 210 to the second mode (S210). The control device 300 transmits confirmation information to the monitoring device 100 with the switching unit 210 in the second mode (S212). When the confirmation information is not received from the second communication unit 114 within a predetermined time after the confirmation information is transmitted to the monitoring device 100 (S214), the control device 300 determines that the second communication unit 114 is out of order (S216). . When the control device 300 receives the confirmation information from the second communication unit 114 within a predetermined time after transmitting the confirmation information to the monitoring device 100 (S214), the control device 300 determines that the second communication unit 114 is normal (S218).

[Effect of the sixth embodiment]
As described above, according to the sixth embodiment, when the monitoring device 100 includes the switching unit 210, the control device 300 causes the first communication unit 112 and the second communication unit 114 included in the relay unit 110 of the monitoring device 100. There is an effect that it is possible to reliably detect which one of the two has failed.

<Seventh Embodiment>
[Monitoring apparatus 100 includes switching unit 210 and bypass unit 120]
FIG. 14 shows a configuration of the monitoring apparatus 100 according to the seventh embodiment. The monitoring apparatus 100 shown in the figure is different from the monitoring apparatus 100 shown in FIG. 12 in that it further includes a bypass unit 120 and an external power supply unit 170. The monitoring apparatus 100 may further include the selection unit 180 described with reference to FIG. 6 and the bypass signal selection unit 190 described with reference to FIG.

  The detour unit 120 causes the downstream monitoring device 100 to detour in response to a detour signal from the upstream monitoring device 100. The bypass unit 120 may cause the upstream monitoring device 100 to bypass the control information under the control of the downstream monitoring device 100.

  The external power supply unit 170 supplies power for driving the bypass unit 120 of the downstream monitoring device 100. The external power supply unit 170 may start supplying power to the downstream monitoring device 100 in synchronization with a change in the detour signal from the upstream monitoring device 100.

  The signal generation unit 160 generates a bypass signal that controls the bypass unit 120 included in the downstream monitoring device 100 in accordance with the control information received from the control device 300 via the relay unit 110. When the control device 300 does not receive the response information within a predetermined time after transmitting the confirmation information to the monitoring device 100, the control device 300 controls the monitoring device 100 via the upstream monitoring device 100 or the downstream monitoring device 100. The control information is bypassed by the bypass unit. The detour unit 120 of the monitoring device 100 detours the control information according to the detour signal generated by the signal generation unit 160 of the upstream monitoring device 100.

  The control device 300 receives the response information from one of the first communication unit 112 and the second communication unit 114 within a predetermined time after the confirmation information is transmitted to the monitoring device 100, and the first communication unit 112 and the second communication. The first communication unit 112 of the downstream monitoring device 100 and the first communication unit 112 within the predetermined time after the control device 300 transmits the confirmation information to the downstream monitoring device 100 in the case where the response information is not received from the other of the units 114 When the response information is not received from one of the second communication units 114, the control device 300 transmits the response information to the downstream monitoring device 100 via the first communication unit 112 or the second communication unit 114 of the monitoring device 100. After transmitting control information including an instruction to be bypassed by the detour unit to the monitoring apparatus 100, control information including an instruction to be bypassed by the detour unit of the monitoring apparatus 100 is transmitted to the upstream monitoring apparatus 100.Hereinafter, the operation of the monitoring system 10 will be specifically described with reference to a communication sequence diagram.

  FIG. 15 shows a communication sequence in the monitoring system 10 of the seventh embodiment. First, the control device 300 confirms whether the upstream monitoring device 100 is operating normally according to the following procedure. The control device 300 transmits confirmation information to the upstream monitoring device 100 in a state where the switching unit 210 of the upstream monitoring device 100 is in the first mode, and receives response information from the upstream monitoring device 100. Next, the control device 300 changes the logical value of the switching signal that controls the switching unit 210 of the upstream monitoring device 100 to switch the switching unit 210 of the upstream monitoring device 100 to the second mode.

  The control device 300 transmits confirmation information to the upstream monitoring device 100 and receives response information from the upstream monitoring device 100 while the switching unit 210 of the upstream monitoring device 100 is in the second mode. When receiving the response information, the control device 300 determines that the first communication unit 112 and the second communication unit 114 of the upstream monitoring device 100 are operating normally, and sets the switching unit 210 of the upstream monitoring device 100 to the first. Switch to the mode.

  Next, the control device 300 confirms whether the monitoring device 100 is operating normally according to the following procedure. The control device 300 transmits confirmation information to the monitoring device 100 and receives response information from the monitoring device 100 with the switching unit 210 of the monitoring device 100 in the first mode. Next, the control device 300 transmits control information including an instruction to switch the switching unit 210 of the monitoring device 100 to the second mode to the upstream monitoring device 100. The upstream monitoring device 100 changes the logical value of the switching signal according to the control information, and switches the switching unit 210 of the monitoring device 100 to the second mode.

  The control device 300 transmits confirmation information to the monitoring device 100 in a state where the switching unit 210 of the monitoring device 100 is in the second mode. Here, in FIG. 15, the control device 300 cannot receive response information from the monitoring device 100. Therefore, the control device 300 determines that the second communication unit 114 of the monitoring device 100 has failed.

  When one of the first communication unit 112 and the second communication unit 114 has failed, the control device 300 determines that the non-failed side of the first communication unit 112 and the second communication unit 114 is from the control device 300. The switching unit 210 is switched to a mode in which control information can be received. In FIG. 15, since the second communication unit 114 of the monitoring device 100 has failed, the control device 300 switches the switching unit 210 to the first mode in which the first communication unit 112 that has not failed can receive control information. Switch.

  Subsequently, the control device 300 transmits control information including an instruction for causing the detour unit 120 of the monitoring device 100 to be in a detour state to the upstream monitoring device 100. The upstream monitoring device 100 changes the logical value of the bypass signal in accordance with the control information, and causes the bypass unit 120 of the monitoring device 100 to enter a bypass state.

  The control device 300 confirms whether or not the downstream monitoring device 100 is operating normally after setting the failed monitoring device 100 to a detour state. Specifically, the switching unit 210 of the downstream monitoring device 100 is sequentially switched between the first mode and the second mode, and the confirmation information is transmitted. The control device 300 can detect the presence / absence of a failure of all the monitoring devices 100 according to the same procedure.

[When a plurality of adjacent monitoring devices 100 are out of order]
FIG. 16A and FIG. 16B show a communication sequence when a plurality of adjacent monitoring devices 100 are out of order. Specifically, FIGS. 16A and 16B show a communication sequence when the first communication unit 112 of the monitoring device 100 and the second communication unit 114 of the downstream monitoring device 100 are out of order.

  The control device 300 transmits confirmation information in a state where the switching unit 210 of the monitoring device 100 is in the first mode. Since the first communication unit 112 of the monitoring device 100 has failed and the control device 300 cannot receive the response information, it is determined that the first communication unit 112 of the monitoring device 100 has failed.

  Subsequently, the control device 300 transmits control information including an instruction to switch the switching unit 210 of the monitoring device 100 to the second mode to the upstream monitoring device 100. The upstream monitoring device 100 changes the logical value of the switching signal to switch the switching unit 210 of the monitoring device 100 to the second mode.

  The control device 300 transmits confirmation information in a state where the switching unit 210 of the monitoring device 100 is in the second mode. Since the second communication unit 114 of the monitoring device 100 has not failed, the control device 300 receives the response information within a predetermined time after transmitting the confirmation information. Through the above procedure, the control device 300 determines that the first communication unit 112 of the monitoring device 100 fails and the second communication unit 114 operates normally. The control device 300 may include a storage unit that stores which side of the first communication unit 112 and the second communication unit 114 is out of order.

  Next, the control device 300 transmits control information including an instruction to set the detour unit 120 of the monitoring device 100 to the detour state to the upstream monitoring device 100. The upstream monitoring device 100 changes the logical value of the detour signal to place the detour unit 120 of the monitoring device 100 in a detour state. The control device 300 transmits confirmation information to the downstream monitoring device 100 in which the switching unit 210 is set to the first mode after the detour unit 120 of the monitoring device 100 enters the detour state.

  Since the first communication unit 112 of the downstream monitoring device 100 is operating normally, the control device 300 receives the response information from the downstream monitoring device 100 within a predetermined time after transmitting the confirmation information. Subsequently, the control device 300 transmits control information including an instruction to set the switching unit 210 of the downstream monitoring device 100 to the second mode to the monitoring device 100. The monitoring device 100 changes the logical value of the switching signal according to the control information, and changes the switching unit 210 of the downstream monitoring device 100 to the second mode.

  The control device 300 transmits a confirmation signal to the downstream monitoring device 100 in a state where the switching unit 210 of the downstream monitoring device 100 is in the second mode. Since the second communication unit 114 of the downstream monitoring device 100 has failed, the control device 300 cannot receive a response signal from the downstream monitoring device 100. With the above procedure, the control device 300 determines that the first communication unit 112 of the downstream monitoring device 100 operates normally and the second communication unit 114 is out of order.

  When the control device 300 determines that the first communication unit 112 of the monitoring device 100 and the second communication unit 114 of the downstream monitoring device 100 are out of order, the control device 300 puts the bypass unit 120 of the monitoring device 100 and the downstream monitoring device 100 into a bypass state. Execute the procedure. Specifically, the control device 300 places the downstream monitoring device 100 in a bypass state after setting the downstream monitoring device 100 in a bypass state among the plurality of faulty monitoring devices 100. By controlling the control device 300 to change to the detour state in this procedure, when a plurality of adjacent monitoring devices 100 are out of order, the plurality of monitoring devices 100 can be set to the detour state.

  As illustrated in FIG. 16B, the control device 300 transmits control information including an instruction to release the detour state of the monitoring device 100 to the upstream monitoring device 100. The upstream monitoring device 100 changes the logical value of the bypass signal in accordance with the control information, and cancels the bypass state of the monitoring device 100.

  After the detour state of the monitoring device 100 is released, the control device 300 switches to a mode in which the control information can be transmitted to the non-failing side of the first communication unit 112 and the second communication unit 114 of the monitoring device 100. The control information including the instruction to switch is transmitted to the upstream monitoring device 100. In the present embodiment, since the first communication unit 112 of the monitoring device 100 has failed, the control device 300 switches the switching unit 210 of the monitoring device 100 to the second mode.

  The control device 300 transmits control information including an instruction to set the bypass unit 120 of the downstream monitoring device 100 to the bypass state to the monitoring device 100 in a state where the switching unit 210 of the monitoring device 100 is in the second mode. The control unit 140 of the monitoring device 100 changes the logical value of the bypass signal in accordance with the control information received via the second communication unit 114, and puts the bypass unit 120 of the downstream monitoring device 100 in a bypass state.

  After the detour unit 120 of the downstream monitoring device 100 enters the detour state, the control device 300 transmits control information including an instruction for causing the detour unit 120 of the monitoring device 100 to enter the detour state to the upstream monitoring device 100. The upstream monitoring device 100 changes the logical value of the bypass signal according to the control information, and puts the bypass unit 120 of the monitoring device 100 in a bypass state. By the above procedure, the monitoring device 100 and the detour unit 120 of the downstream monitoring device 100 enter a detour state, and the control device 300 can transmit control information to the monitoring device 100 further downstream of the downstream monitoring device 100.

[Effect of the seventh embodiment]
As described above, according to the seventh embodiment, even if any one of the first communication unit 112 and the second communication unit 114 fails in the plurality of adjacent monitoring devices 100, the plurality of adjacent monitoring devices 100 are adjacent to each other. The monitoring apparatus 100 can be put into a detour state. As a result, even when a plurality of monitoring devices 100 are out of order, the control device 300 transmits and receives control information and monitoring information to and from the monitoring devices 100 downstream of the plurality of monitoring devices 100 that are out of order. The effect of being able to do.

<Eighth Embodiment>
[Enables repair of the monitoring device 100 with the bypass unit 120 operated]
FIG. 17 shows a configuration of the monitoring apparatus 100 according to the eighth embodiment. The monitoring apparatus 100 shown in the figure is different from the monitoring apparatus 100 shown in the above embodiment in that it includes a terminal block 220, an internal power supply unit 230, a power supply switching unit 240, and a connector 250. The monitoring device 100 may further include a switching unit 210.

  The monitoring device 100 is supplied with power from an AC power source or a DC power source via the terminal block 220. For example, an AC voltage of 100V is input to the terminal block 220. The terminal block 220 may be connected to the terminal block 220 of the upstream monitoring device 100 and the downstream monitoring device 100.

  The internal power supply unit 230 generates power for operating the internal circuit 105 including the relay unit 110. The internal circuit 105 includes a circuit that is not connected to the connection unit 150 or the connection unit 152. Specifically, the internal circuit 105 includes a relay unit 110, a monitoring unit 130, a control unit 140, and a signal generation unit 160. As an example, the internal circuit 105 is mounted on a substrate or unit that is separated from other parts of the monitoring apparatus 100.

  As an example, the internal power supply unit 230 is an AC / DC converter that converts an AC voltage received via the terminal block 220 into a DC voltage that causes the internal circuit 105 to operate. The internal power supply unit 230 applies the converted DC voltage to the internal circuit 105 via the power supply switching unit 240 and the connector 250.

  The power supply switching unit 240 switches whether to apply the power generated by the internal power supply unit 230 to the internal circuit 105 according to a detour signal input from the upstream monitoring device 100 or the downstream monitoring device 100. The power supply switching unit 240 is a relay, for example. The power supply switching unit 240 may be driven by a voltage generated by the internal power supply unit 230 or may be driven by a voltage supplied from the upstream monitoring device 100.

  In the monitoring device 100, the power supply switching unit 240, the detour unit 120, and the selection unit 180 are switched according to the detour signal input from the upstream monitoring device 100 or the downstream monitoring device 100. As a result, the internal circuit 105 is disconnected from the internal power supply unit 230, the connection unit 150, the connection unit 152, and the selection unit 180. In this state, the internal circuit 105 is not electrically coupled to the internal power supply unit 230, the connection unit 150, the connection unit 152, and the selection unit 180, so that the internal circuit 105 can be disconnected from the connector 250.

[Effect of Eighth Embodiment]
As described above, according to the eighth embodiment, when the bypass unit 120 enters the bypass state, the internal circuit 105 can be removed while the control information and the monitoring information are bypassed by the bypass unit 120. Therefore, there is an effect that the internal circuit 105 of the failed monitoring device 100 can be repaired or replaced without stopping the operation of the monitoring system 10.

<Ninth Embodiment>
[Monitoring system in which a plurality of monitoring devices 100 are connected in a loop]
FIG. 18 shows the configuration of the monitoring system 10 of the ninth embodiment. The monitoring system 10 shown in the figure is different from the monitoring system 10 shown in FIG. 1 in that it includes a plurality of monitoring devices 100 connected in a loop.

  Specifically, the monitoring device 100-1 is connected to the control device 300, and sequentially connected to the adjacent monitoring devices 100. The terminal monitoring device 100-n is connected to the control device 300. The control device 300 can transmit the control information in either the direction from the monitoring device 100-1 to the monitoring device 100-n or the direction from the monitoring device 100-n to the monitoring device 100-1. In the monitoring system 10 of this embodiment, the monitoring devices 100-n,..., The monitoring device 100-2, and the monitoring device 100-1 are rotated clockwise, the monitoring device 100-1, the monitoring device 100-2,. ..., the direction of the monitoring device 100-n is referred to as counterclockwise.

  The monitoring system 10 according to the present embodiment can switch whether the control information and the monitoring information are transmitted clockwise or counterclockwise based on an instruction from the control device 300. For example, when the control device 300 detects the monitoring device 100 that has failed, the control device 300 switches the transmission direction of the control information and the monitoring information.

  The relay unit 110 of each monitoring device 100 identifies the control device 300 and the plurality of monitoring devices 100 that are stored in association with the first communication unit 112 and the second communication unit 114 in response to an instruction from the control device 300. By changing the control information, it is possible to switch whether the control information or the monitoring information including the identification information of each monitoring device 100 as a destination is to be transmitted from the first communication unit 112 or the second communication unit 114.

  For example, the relay unit 110 of the monitoring device 100-2 stores the identification information of the control device 300 in association with the first communication unit 112 when the monitoring device 100-1 has not failed, and the monitoring device 100-2. Transmits the monitoring information to be transmitted to the control device 300 from the first communication unit 112. The relay unit 110 of the monitoring device 100-2 stores the identification information of the control device 300 in association with the second communication unit 114 and transmits the information to the control device 300 when the monitoring device 100-1 has failed. Information is transmitted from the second communication unit 114.

  In the present embodiment, since the transmission direction of the control information can be switched, the control device 300 changes the monitoring device 100 to a plurality of adjacent ones based on the state of the plurality of monitoring devices 100 adjacent to the monitoring device 100. It may be selected which of the monitoring devices 100 controls whether the bypass unit 120 and the switching unit 210 are controlled. Specifically, the monitoring device 100 switches between the bypass unit 120 and the switching unit 210 under the control of the monitoring device 100 that receives control information.

  For example, the control device 300 includes control information including an instruction to cause the monitoring device 100-3 to control the bypass unit 120 or the switching unit 210 of the monitoring device 100-2 when the monitoring device 100-1 is out of order. Send. When the monitoring device 100-3 is out of order, the control device 300 sends control information including an instruction to cause the monitoring device 100-1 to control the bypass unit 120 or the switching unit 210 of the monitoring device 10-2. Send.

[Effects of Ninth Embodiment]
As described above, according to the ninth embodiment, the control device 300 can switch the direction in which the control information and the monitoring information are transmitted. Therefore, the control device 300 and the plurality of monitoring devices 100 can transmit the control information and the monitoring information without using the failed monitoring device 100 when the failed monitoring device 100 exists. .

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Monitoring system, 50 ... Communication line, 100 ... Monitoring apparatus, 105 ... Internal circuit, 110 ... Relay part, 112 ... 1st communication part, 114 ... 2nd Communication unit 120 ... Detour unit 130 ... Monitoring unit 140 ... Control unit 150 ... Connection unit 152 ... Connection unit 160 ... Signal generation unit 170 ... Power supply unit, 180 ... selection unit, 182 ... selection signal generation unit, 184 ... signal selection unit, 190 ... detour signal selection unit, 192 ... photocoupler, 194 ... photocoupler, 210 ... Switching unit, 220 ... Terminal block, 230 ... Internal power supply unit, 240 ... Power supply switching unit, 250 ... Connector, 300 ... Control device, 400 ... Hub, 500 ···monitor

Claims (6)

A monitoring system comprising: a plurality of monitoring devices connected in a daisy chain; and a control device that transmits control information to the plurality of monitoring devices and receives monitoring information acquired by each of the plurality of monitoring devices,
The monitoring device
A first communication unit communicating with an upstream monitoring device located upstream of the daisy chain connection with respect to the monitoring device; and a second communication unit communicating with a downstream monitoring device located downstream of the daisy chain connection with respect to the monitoring device. A relay unit that relays the control information and the monitoring information communicated between the upstream monitoring device and the downstream monitoring device via the first communication unit and the second communication unit,
A detour unit for detouring the control information to the downstream monitoring device and detouring the monitoring information to the upstream monitoring device by the control of the control device via the upstream monitoring device or the downstream monitoring device;
A monitoring system comprising: a signal generation unit that generates a bypass signal that controls the bypass unit of the downstream monitoring device according to the control information received from the control device via the relay unit.   The monitoring device further includes an external power supply unit that supplies power to the downstream monitoring device and starts supplying the power to the downstream monitoring device in synchronization with a change in the bypass signal generated by the signal generation unit. The monitoring system according to claim 1.   The monitoring device further includes a selection unit that selects whether to output the bypass signal generated by the signal generation unit or the bypass signal generated by the upstream monitoring device to the downstream monitoring device. The monitoring system according to 1 or 2. The bypass unit of the monitoring device bypasses the control information and the monitoring information according to a change in the logical value of the bypass signal generated by the upstream monitoring device,
The monitoring system according to claim 3, wherein the selection unit selects the bypass signal generated by the upstream monitoring device according to a change in a logical value of the bypass signal generated by the upstream monitoring device. The monitoring device
An internal power supply that generates power to operate the relay unit;
The monitoring system according to any one of claims 1 to 4, further comprising: a power supply switching unit that switches whether to supply the power generated by the internal power supply unit to the relay unit according to the bypass signal. The controller is
When the response information for the control information transmitted to the downstream monitoring device is not received within a predetermined time, the control information is retransmitted to the downstream monitoring device after the detour unit of the monitoring device is in a detour state, and
When the response information for the retransmitted control information is received within a predetermined time, it is determined that the monitoring device has failed,
The monitoring system according to claim 1, wherein if the response information for the retransmitted control information is not received within a predetermined time, it is determined that the downstream monitoring device has failed.

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