JP2022110497A - IO unit and end unit - Google Patents

Abstract

To provide an IO unit system capable of appropriately detecting an abnormality in the supply state of IO power supply.SOLUTION: An IO unit (20A) includes: first power input terminals (221) that receive first power from other connected IO units; a power port (211) supplying the first power to a device connected to the power port; power lines (4) connecting the first power terminal and the power port; and a monitoring unit (50) for monitoring whether or not the first power is being supplied to the power line by measuring the voltage of the power line.SELECTED DRAWING: Figure 5

Description

The present invention relates to IO units and end units.

Conventionally, an IO unit system is known that includes a plurality of IO units that perform predetermined input/output control for externally connected devices. Patent Document 1 discloses a PLC device having an end cover with a bus interface, a bus function register, and a bus failure diagnosis register. Patent Literature 2 discloses a remote I/O unit provided with overcurrent detection means for detecting overcurrent in a power line that supplies power to an externally connected device.

JP 2011-070284 A Japanese Patent Application Laid-Open No. 2009-099002

However, the PLC device described in Patent Document 1 is for diagnosing failures of the bus, and is not for monitoring the state of power supply to externally connected devices. In the remote IO unit described in Patent Literature 2, power for internal circuits and power for externally connected devices are supplied from the same external power supply. Therefore, if a voltage drop occurs in the external power supply due to multiple connections of IO units or poor contact between IO units, sufficient power will not be supplied to the internal circuit including the overcurrent detection means, and the detection operation by the overcurrent detection means will be interrupted. may not be able to do That is, the remote IO unit described in Patent Document 2 cannot detect the voltage drop of the IO power supply.

An aspect of the present invention has been made in view of the above problems, and is to provide an IO unit system capable of appropriately detecting an abnormality in the IO power supply state.

To solve the above problems, an IO unit according to an aspect of the present invention provides a first power supply input terminal that receives first power from another connected IO unit, and a device connected to a power supply port. a power port that supplies first power; a power line that connects the first power terminal and the power port; and the first power is supplied to the power line by measuring a voltage of the power line. and a monitoring unit for monitoring whether or not there is.

According to the above configuration, the IO unit can monitor the supply state of the first power by including the monitoring section. Thereby, the monitoring unit can detect an abnormality in the supply state of the first power to the power supply line. Also, the monitoring unit monitors the voltage of the power supply line as the supply state of the first power. Therefore, compared with the case of monitoring the current of the power supply line, it is possible to detect the voltage drop of the first power due to multiple connections or poor contact. Therefore, multiple connections or poor contact can be detected.

Further, the monitoring unit includes a determination unit that determines whether or not the first power is being supplied to the power supply line, and a display that displays the supply state of the first power to a user based on the determination result of the determination unit. and a controller.

According to the above configuration, the display control unit displays the supply state of the first power to the user, so that the user can easily identify the location of the abnormality when there is an abnormality in the supply state of the first power. .

The monitoring unit includes a determination unit that determines whether or not the first power is supplied to the power supply line, and a notification unit that notifies a controller that controls the IO unit of the determination result of the determination unit. , may be provided.

According to the above configuration, it is possible to notify the controller that controls the IO unit of the supply state of the first power. The controller can notify the user of the supply status.

Further, when the value corresponding to the voltage of the power supply line is equal to or greater than a predetermined first threshold, the determination unit determines that the power supply line is in a first state in which the first power is normally supplied. , if the value corresponding to the voltage of the power supply line is equal to or greater than a predetermined second threshold smaller than the first threshold and less than the first threshold, the first power is sufficiently supplied to the power supply line; When it is determined that the voltage drop occurs in a second state, and the value corresponding to the voltage of the power supply line is less than the second threshold value, the first power is not appropriately supplied to the power supply line. It may be determined that there are three states.

According to the above configuration, it is possible to detect the second state in which the first power is sufficiently supplied to the power supply line but the voltage drop occurs. Therefore, the user can improve the abnormal location before a problem occurs.

In addition, the IO unit further includes a power output terminal for outputting the first electric power to a further connected IO unit, and the power line connects the first power input terminal and the power output terminal. You may

Further, the IO unit may further include a second power supply input terminal that receives a second power from the connected other IO unit, and the circuit that constitutes the monitoring section may operate with the second power.

According to the above configuration, the first power supplied to the device via the power port and the second power for operating the circuit forming the monitoring section are supplied from different terminals of the IO unit. Therefore, even if a voltage drop occurs in the first power due to multiple connections or poor contact, the circuit forming the monitoring unit can operate with the second power supplied from a different terminal. Therefore, even if the first power is not properly supplied, an abnormality in the supply state of the first power can be detected.

In order to solve the above problems, an end unit according to one aspect of the present invention is an end unit connected to a terminal side of a plurality of IO units connected to each other, wherein a device connected to the IO units a first power supply input terminal connected to a first power supply line of the IO unit for supplying a first power; a second power supply line connected to the first power supply input terminal; and a voltage of the second power supply line a monitoring unit for monitoring whether power is being supplied to the second power supply line by measuring

According to the above configuration, the end unit can monitor the supply state of the first power by including the monitoring section. Thereby, the monitoring unit can detect an abnormality in the supply state of the first power to the power supply line. Also, the monitoring unit monitors the voltage of the power supply line as the supply state of the first power. Therefore, compared with the case of monitoring the current of the power supply line, it is possible to detect the voltage drop of the first power due to multiple connections or poor contact. Also, the end unit originally connected for the purpose of protecting the terminal side of the IO unit has a monitoring section. That is, the structure can be simplified by providing a new member including the monitoring unit.

The monitoring unit includes a determination unit that determines whether or not the first power is being supplied to the second power supply line, and a display that displays the state of supply of the first power to a user based on the determination result of the determination unit. and a controller.

The monitoring unit includes a determination unit that determines whether or not the first power is supplied to the second power supply line, and a notification unit that notifies a controller that controls the IO unit of the determination result of the determination unit. , may be provided.

When the value corresponding to the voltage of the second power supply line is equal to or greater than a predetermined first threshold, the determination unit determines that the first state in which the first power is normally supplied to the second power supply line. If the value corresponding to the voltage of the second power supply line is equal to or greater than a predetermined second threshold smaller than the first threshold and less than the first threshold, the first power is supplied to the second power supply line. However, if it is determined that the voltage drop occurs in the second state and the value corresponding to the voltage of the second power supply line is less than the second threshold value, the first power is supplied to the second power supply line. may be determined to be in a third state in which is not normally supplied.

The end unit may further include a second power supply input terminal that receives a second power from the termination side of the plurality of IO units, and the circuit that constitutes the monitoring unit may operate with the second power.

According to one aspect of the present invention, there is provided an IO unit system capable of appropriately detecting an abnormality in the IO power supply state.

1 is a schematic diagram showing a schematic configuration of an IO unit system; FIG. FIG. 10A is a front perspective view, a front view, and a rear perspective view of an IO unit; FIG. 10 is a diagram showing an abnormality in the IO power supply state due to poor contact in the IO unit system; FIG. 10 is a diagram showing an abnormality in the IO power supply state due to multiple connections in the IO unit system; FIG. 2 is a block diagram showing an example of the main configuration of an IO unit according to one embodiment of the present invention; FIG. 5 is a diagram showing how the IO unit detects an abnormality in the IO power supply state; FIG. 11 is a block diagram showing an example of a main configuration of an end unit according to another embodiment of the present invention; FIG. 5 is a diagram showing how the end unit detects an abnormality in the IO power supply state;

EMBODIMENT OF THE INVENTION Hereinafter, embodiment (it is also described as "this embodiment" hereafter) which concerns on one aspect of this invention is described based on drawing. However, this embodiment described below is merely an example of the present invention in every respect. It goes without saying that various modifications and variations can be made without departing from the scope of the invention. That is, in implementing the present invention, a specific configuration according to the embodiment may be appropriately adopted.

§1 Application example (Outline configuration of IO unit system 1)
An example of a scene to which the present invention is applied will be described with reference to FIGS. 1 to 4. FIG. FIG. 1 is a schematic diagram showing a schematic configuration of an IO unit system 1. As shown in FIG. As shown in FIG. 1, the IO unit system 1 includes a communication coupler unit 10, a plurality of IO units 20, and an end unit 30. As shown in FIG. The communication coupler unit 10 is connected to a higher-level master device via a network. The IO unit system 1 performs predetermined input/output control for externally connected equipment (devices).

The communication coupler unit 10 receives a start instruction to start power supply from a master device (not shown). Note that the IO unit system 1 may include a PLC (Programmable Logic Controller) unit, which is a master device, instead of the communication coupler unit 10 .

The communication coupler unit 10 includes a communication section (not shown) for exchanging data with a master device, a power supply terminal block 11 and a connector 12 . The power terminal block 11 is provided with an IO power supply terminal 111 connected to the external IO power supply 2 and a unit power supply terminal 112 connected to the external unit power supply 3 . The connector 12 is provided with an IO power output terminal 121, a unit power output terminal 122, and a communication terminal (not shown).

Inside the communication coupler unit 10, the IO power supply terminal 111 is connected to the IO power output terminal 121 by the IO power supply line 4 (first power supply line). Inside the communication coupler unit 10 , the unit power supply terminal 112 is connected to the internal power supply circuit 13 and the unit power supply output terminal 122 via the bus power supply circuit 15 . The internal power supply circuit 13 is connected to the internal circuit 14 of the communication coupler unit 10 . Further, inside the communication coupler unit 10, the communication section is connected to communication terminals of the connector 12 by a communication line (not shown).

Each of the plurality of IO units 20 includes a terminal block 21 , a higher level connector 22 and a lower level connector 23 . The upper side connector 22 and the lower side connector 23 are provided on both side surfaces of the IO unit 20 (see FIG. 2). The terminal block 21 is provided with a plurality of power ports 211 that are connected to externally connected devices. The host connector 22 is provided with an IO power input terminal 221 (first power input terminal), a unit power input terminal 222 (second power input terminal), and a communication terminal (not shown). The lower connector 23 is provided with an IO power output terminal 231 (power output terminal), a unit power output terminal 232, and a communication terminal (not shown).

A plurality of IO units 20 are connected in series to the communication coupler unit 10 . Specifically, the connector 12 of the communication coupler unit 10 and the IO connector 12 are arranged so that the corresponding terminals (IO power output terminal 121 and IO power input terminal 221, unit power output terminal 122 and unit power input terminal 222) are connected to each other. It is connected to the upper connector 22 of the unit 20a. Similarly, the upper connectors 22 of the IO units 20b-20e and the lower connectors 23 of the IO units 20a-20d are connected, respectively. Although FIG. 1 shows an example in which five IO units 20a to 20e are connected in series to the communication coupler unit 10, the number of IO units is not limited to this.

The IO power input terminal 221 receives IO power (first power) from the IO power output terminal 121 of the communication coupler unit 10 or the IO power output terminal 231 of the IO unit 20 connected to the upper side. The unit power input terminal 222 receives unit power (second power) from the unit power output terminal 122 of the communication coupler unit 10 or the unit power output terminal 232 of the IO unit 20 connected to the upper side.

Inside the plurality of IO units 20 , the IO power supply input terminal 221 is connected to the power supply port 211 and the IO power supply output terminal 231 via the IO power supply line 4 . Inside the plurality of IO units 20 , the unit power supply input terminal 222 is connected to the internal power supply circuit 27 and the unit power supply output terminal 232 via the unit power supply line 5 . The internal power supply circuit 27 is connected to the internal circuit 24 of each IO unit 20 by the unit power supply line 5 . Further, inside the plurality of IO units 20, the communication terminals of the upper connector 22 are connected to the communication terminals of the lower connector 23 by communication lines.

Note that the IO power supply 2 and the unit power supply 3 are typically DC24V power supplies. The bus power supply circuit 15 steps down the power voltage supplied from the unit power supply 3 (for example, from DC 24V to DC 5.8V). The bus power supply circuit 15 supplies the reduced power to the internal power supply circuits 13 and 27 . The internal power supply circuits 13 and 27 step down the power voltage supplied from the bus power supply circuit 15 (for example, from DC 5.8V to DC 3.3V or DC 1.2V). The internal power supply circuits 13 and 27 supply stepped-down power to the internal circuits 14 and 24, respectively.

In addition, among the plurality of terminals of each connector (connector 12, upper connector 22, lower connector 23), two are used for IO power supply + and IO power supply -, and two are used for unit power supply + and unit power supply -. , the rest are used for communication lines.

The end unit 30 is connected to the terminal side (IO unit 20e) of the plurality of IO units 20 that are connected to each other. The end unit 30 is a cover member that protects the lower connector 23 of the IO unit 20e.

With the above configuration, the IO power supplied from the IO power supply 2 is supplied to the externally connected device connected to the power supply port 211 via the IO power supply line 4 . Unit power supplied from the unit power supply 3 is supplied to the internal circuits 14 and 24 via the unit power supply line 5 . Also, the communication section of the communication coupler unit 10 exchanges data with each IO unit 20 via a communication line.

(Schematic configuration of IO unit 20)
2 shows a front perspective view (2A in FIG. 2), a front view (2B in FIG. 2), and a rear perspective view (2C in FIG. 2) of the IO unit 20. FIG. As shown in FIG. 2 , the IO unit 20 includes a terminal block 21 , an upper connector 22 , a lower connector 23 , an engaging portion 25 and an engaged portion 26 . Hereinafter, the side of the IO unit 20 where the terminal block 21 is located is defined as the front, the opposite side is defined as the rear, the left is defined as the left, and the right is defined as the right.

The terminal block 21 is provided on the front surface of the IO unit 20 . The terminal block 21 has a plurality of power ports 211 for connecting externally connected devices. In the illustration of FIG. 2, the power port 211 has 16 terminals.

The upper connector 22 is provided on the right side surface of the IO unit 20 . The lower side connector 23 is provided on the left side surface of the IO unit 20 . Each IO unit 20 is electrically connected by an upper connector 22 and a lower connector 23 .

An engaging portion 25 is provided on the right side of the upper and lower ends of the front surface of the IO unit 20 . An engaged portion 26 is provided on the left side of the upper and lower ends of the front surface of the IO unit 20 . The engaging portion 25 and the engaged portion 26 are guides for connecting each IO unit 20 .

FIG. 3 is a diagram showing an abnormality in the IO power supply state due to poor contact in the IO unit system 1. As shown in FIG. FIG. 3 shows an example in which four IO units 20a-20d are connected in series to the communication coupler unit 10. FIG. In the following, for the sake of simplicity, the description will be made with reference to the illustration of FIG.

As shown in FIG. 3, when there is a contact failure in the terminal corresponding to the IO power between the IO unit 20c and the IO unit 20d, the IO power is not normally supplied to the IO unit 20d. Therefore, the externally connected device connected to the IO unit 20d does not operate normally. On the other hand, since there is no contact failure in the terminals corresponding to the unit power, the unit power is supplied to the IO unit 20d. Therefore, the internal circuit 24 of the IO unit 20d is normally driven.

In the conventional IO unit system 1, when the unit power is not supplied to the IO unit 20, the internal circuit 24 does not operate, so it is easy to detect an abnormality in the unit power supply state. On the other hand, the conventional IO unit system 1 does not have the function of detecting whether IO power is supplied to the IO unit 20 or not. Therefore, when there is no contact failure in the terminal corresponding to the unit power but there is contact failure in the terminal corresponding to the IO power as shown in FIG. 3, it is difficult to identify the cause of the externally connected device not operating.

FIG. 4 is a diagram showing an abnormality in the IO power supply state due to multiple connections in the IO unit system. As shown in FIG. 4, contact resistance R exists in each connector connecting portion of each IO unit 20 . Here, let the voltage of the IO power supply 2 be 24 V, and let I be the load current flowing through the IO power supply line 4 to the externally connected device. At this time, the voltage of the IO power supplied from the communication coupler unit 10 to the N-th IO unit 20 is represented by 24-I×R×N. For example, when I=2A and R=0.1Ω, the voltage of the IO power supplied from the communication coupler unit 10 to the sixth IO unit 20 (that is, N=6) is 22.8V. Also, the voltage of the IO power supplied from the communication coupler unit 10 to the twentieth (that is, N=20) IO unit 20 is 20.0V. Here, the power supply voltage specification range of the externally connected device is 20.4V to 26.4V. At this time, since a sufficient IO power supply voltage is not supplied to the 20th IO unit 20, the externally connected device connected to the 20th IO unit 20 does not operate normally. In the conventional IO unit system 1, even when there is a voltage drop in the IO power due to multiple connections of the IO units 20 as described above, it is difficult to identify the cause of the non-operation of the externally connected device.

As shown in FIGS. 3 and 4, the conventional IO unit system 1 cannot easily detect IO power voltage drop due to poor contact or multiple connections. On the other hand, the IO unit system 1 according to the present embodiment can easily detect the voltage drop of the IO power by providing the IO unit or the end unit with the monitoring unit 50, which will be described later.

§2 Configuration example [Embodiment 1]
(Configuration of IO unit 20A)
An IO unit system 1 according to an embodiment of the present invention includes a plurality of IO units 20 including at least one IO unit 20A having a monitoring section 50 (see FIG. 6).

FIG. 5 is a block diagram showing an example of the main configuration of the IO unit 20A according to one embodiment of the invention. As shown in FIG. 5, the IO unit 20A includes a terminal block 21, an upper connector 22, a lower connector 23, an internal power supply circuit 27, and a monitor 50. Note that the circuit forming the monitoring unit 50 is part of the internal circuit 24 in FIG. That is, the circuit forming the monitoring section 50 is driven by power supplied from the unit power supply 3 through the unit power supply line 5 .

The terminal block 21 may have terminals for measurement. A user can directly measure the voltage of the IO power supply line 4 by applying a tester to the measurement terminal.

The monitoring unit 50 includes a step-down circuit 51 , an AD converter 52 , a determination unit 53 , a display control unit 54 and a notification unit 55 . The monitoring unit 50 monitors the IO power supply state in the IO unit 20A. In addition, the monitoring unit 50 displays information indicating the supply state to the user or notifies the controller.

The step-down circuit 51 is connected to the IO power supply input terminal 221 and the IO power supply line 4 . The step-down circuit 51 steps down the voltage of the IO power supply line 4 . The step-down circuit 51 outputs the stepped-down voltage of the IO power supply line 4 to the AD converter 52 .

The AD converter 52 converts the voltage of the IO power supply line 4 as an analog signal input from the step-down circuit 51 into an IO power supply voltage value V1 as a digital signal. The AD converter 52 outputs the IO power supply voltage value V1 to the determination section 53 .

The determination unit 53 determines the IO power supply state based on the IO power supply voltage value V1 acquired from the AD converter 52 . For example, when the IO power supply voltage value V1 is equal to or greater than a predetermined first threshold value, the determination unit 53 determines that the IO power supply line 4 is in the first state in which the IO power is normally supplied. If the IO power supply voltage value V1 is equal to or more than a second threshold value that is smaller than the first threshold value and is less than the first threshold value, the determination unit 53 determines that the IO power is supplied to the IO power supply line 4, but the voltage It is determined that the second state is the descent. When the IO power supply voltage value V1 is less than the second predetermined threshold value, the determination unit 53 determines that the IO power supply line 4 is in the third state in which the IO power is not normally supplied. The predetermined second threshold is set, for example, to the lower limit of the power supply voltage specification range of the externally connected device. The predetermined first threshold and the predetermined second threshold may be arbitrarily set according to the power supply voltage specification range of the externally connected device. The determination unit 53 outputs the determination result of the IO power supply state to the display control unit 54 and the notification unit 55 . The determination unit 53 is, for example, an internal processing circuit (MPU) of the IO unit 20A.

The display control unit 54 performs display control of a display unit (not shown) based on the determination result acquired from the determination unit 53 . For example, the display section is an LED provided in the IO unit 20A, and the display control section 54 is an LED display circuit. In this case, the display control unit 54 turns on the green LED when it obtains from the determination unit 53 the determination result that the IO power is normally supplied to the first state. When the display control unit 54 acquires the determination result from the determination unit 53 that it is in the second state in which the IO power is supplied but the voltage drop occurs, the display control unit 54 blinks the green LED. When the display control unit 54 acquires the determination result from the determination unit 53 that the IO power supply line 4 is in the third state in which the IO power is not normally supplied, the display control unit 54 lights the red LED. With such a configuration, the display control unit 54 can notify the user of the IO power supply state. Note that the display method of the display unit based on the supply state of the IO power supply 2 is not limited to this.

The notification unit 55 notifies the communication unit of the communication coupler unit 10 via the communication line 6 based on the determination result acquired from the determination unit 53 . The communication section of the communication coupler unit 10 notifies the controller of the determination result. The notification unit 55 is, for example, an ASIC (Application Specific Integrated Circuit) for bus communication.

With the above configuration, the IO unit system 1 includes the monitoring unit 50, so that the IO unit 20A can monitor the supply state of the IO power. Thereby, the monitoring unit 50 can detect an abnormality in the supply state of the IO power to the IO power supply line 4 .

In addition, the monitoring unit 50 monitors the voltage of the IO power supply line 4 as the IO power supply state. Therefore, compared with the case of monitoring the current of the IO power supply line 4, it is possible to detect the voltage drop of the IO power due to multiple connections or poor contact.

(Detection by IO unit 20A)
FIG. 6 is a diagram showing how the IO unit 20A detects an abnormality in the supply state of the IO power supply 2. As shown in FIG. FIG. 6 shows an example in which of the five IO units 20, the second IO unit 20Aa from the communication coupler unit 10 and the fifth IO unit 20Ab from the communication coupler unit 10 are provided with the monitoring section 50. . In the following, for simplicity, the description will be made with reference to the illustration of FIG.

As shown in FIG. 6, when the monitoring unit 50 of the IO unit 20Aa determines that there is no abnormality in the IO power supply state, and the monitoring unit 50 of the IO unit 20Ab determines that there is an abnormality in the IO power supply state, It can be seen that there is an abnormality in the IO power supply state between the IO unit 20Aa and the IO unit 20Ab. In addition, the IO unit system 1 includes a plurality of IO units 20A, making it easier to identify the cause of an abnormality in the IO power supply state, compared to a configuration in which an end unit includes a monitoring unit 50, which will be described later. .

Alternatively, only some of the IO units 20 may include the monitoring section 50 . With a configuration in which only some IO units include the monitoring unit 50, it is possible to detect an abnormality in the IO power supply state without incurring costs.

[Embodiment 2]
Other embodiments of the invention are described below. For convenience of description, members having the same functions as those of the members described in the above embodiments are denoted by the same reference numerals, and description thereof will not be repeated.

(Configuration of end unit 30A)
FIG. 7 is a block diagram showing an example of the main configuration of an end unit 30A according to another embodiment of the invention. As shown in FIG. 7, the end unit 30A includes a connector 32, an internal power supply circuit 33, and a monitoring section 50. As shown in FIG. The connector 32 is provided with an IO power input terminal 321, a unit power input terminal 322, and a communication terminal (not shown). The end unit 30 is connected via a connector 32 to terminal sides of a plurality of IO units that are connected to each other. Specifically, the lower connector 23 of the IO unit 20 and the end unit are connected so that the corresponding terminals (IO power output terminal 231 and IO power input terminal 321, unit power output terminal 232 and unit power input terminal 322) are connected. 30 and a connector 32 are connected.

The internal power supply circuit 33 is connected to the unit power supply input terminal 322 by the unit power supply line 8 . Also, the internal power supply circuit 33 is connected to the monitoring section 50 by the unit power supply line 8 . With such a configuration, the monitoring section 50 is driven by the unit power supplied to the end unit 30A.

The configuration of the monitoring section 50 of the end unit 30A is the same as that of the monitoring section 50 of the IO unit 20A according to the first embodiment. The step-down circuit 51 is connected to the IO power supply input terminal 321 and the IO power supply line 7 (second power supply line). The step-down circuit 51 acquires the voltage of the IO power supply line 7 and steps down the voltage.

(Detection by end unit 30A)
FIG. 8 is a diagram showing how the end unit 30A detects an abnormality in the IO power supply state. FIG. 8 shows an example in which an end unit 30A is connected to the end sides of four IO units 20. As shown in FIG. In the following, for simplicity, the description will be made with reference to the illustration of FIG.

As shown in FIG. 8, when there is an abnormality in the IO power supply state in any one of the plurality of IO units 20, the monitoring unit 50 can detect the abnormality in the IO power supply state.

[Example of realization by software]
The control blocks of the monitoring unit 50 (especially the determination unit 53, the display control unit 54, and the notification unit 55) may be realized by a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like, or may be implemented by software. may be realized by

In the latter case, the monitoring unit 50 is provided with a computer that executes instructions of a program, which is software that implements each function. This computer includes, for example, one or more processors, and a computer-readable recording medium storing the above program. In the computer, the processor reads the program from the recording medium and executes it, thereby achieving the object of the present invention. As the processor, for example, a CPU (Central Processing Unit) can be used. As the recording medium, a "non-temporary tangible medium" such as a ROM (Read Only Memory), a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like can be used. In addition, a RAM (Random Access Memory) for developing the above program may be further provided. Also, the program may be supplied to the computer via any transmission medium (communication network, broadcast wave, etc.) capable of transmitting the program. Note that one aspect of the present invention can also be implemented in the form of a data signal embedded in a carrier wave in which the program is embodied by electronic transmission.

The present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. is also included in the technical scope of the present invention.

1 IO unit system 2 IO power supply 3 Unit power supply 4 IO power supply line (first power supply line)
7 IO power supply line (second power supply line)
10 Communication coupler unit 20A IO unit 30A End unit 50 Monitoring unit 53 Judging unit 54 Display control unit 55 Notification unit 211 Power supply ports 221, 321 IO power supply input terminal (first power supply input terminal)
222, 322 Unit power supply input terminal (second power supply input terminal)
231 IO power output terminal (power output terminal)

Claims (11)

an IO unit,
a first power input terminal for receiving first power from other connected IO units;
the power port providing the first power to a device connected to the power port;
a power line connecting the first power input terminal and the power port;
an IO unit that monitors whether or not the first power is being supplied to the power line by measuring the voltage of the power line. The monitoring unit includes a determination unit that determines whether or not the first power is being supplied to the power supply line, and a display control unit that displays the supply state of the first power to a user based on the determination result of the determination unit. The IO unit of claim 1, comprising: The monitoring unit includes a determination unit that determines whether or not the first power is supplied to the power supply line, and a notification unit that notifies a controller that controls the IO unit of the determination result of the determination unit. The IO unit of claim 1, comprising: The determination unit is
determining that a first state in which the first power is normally supplied to the power supply line is in a first state when the value corresponding to the voltage of the power supply line is equal to or greater than a predetermined first threshold;
When the value corresponding to the voltage of the power supply line is equal to or greater than a predetermined second threshold smaller than the first threshold and less than the first threshold, the first power is supplied to the power supply line, but a voltage drop occurs. Determining that it is the second state that has occurred,
4. The apparatus according to claim 2, wherein when the value corresponding to the voltage of the power supply line is less than the second threshold, it is determined that the power supply line is in a third state in which the first power is not normally supplied to the power supply line. IO unit. further comprising a power supply output terminal for outputting the first power to a further connected IO unit;
5. The IO unit according to claim 1, wherein said power line connects said first power input terminal and said power output terminal. further comprising a second power input terminal for receiving a second power from the other connected IO unit;
6. The IO unit according to any one of claims 1 to 5, wherein a circuit forming said monitoring unit operates with said second power. An end unit connected to a terminal side of a plurality of IO units connected to each other,
a first power input terminal connected to a first power supply line of the IO unit for supplying a first power to a device connected to the IO unit;
a second power line connected to the first power input terminal;
an end unit that monitors whether power is being supplied to the second power line by measuring the voltage of the second power line. The monitoring unit includes a determination unit that determines whether or not the first power is being supplied to the second power supply line, and a display that displays the state of supply of the first power to a user based on the determination result of the determination unit. 8. The end unit of claim 7, comprising a controller. The monitoring unit includes a determination unit that determines whether or not the first power is supplied to the second power supply line, and a notification unit that notifies a controller that controls the IO unit of the determination result of the determination unit. 8. The end unit of claim 7, comprising: The determination unit is
determining that a first state in which the first power is normally supplied to the second power line is in a first state when a value corresponding to the voltage of the second power line is equal to or greater than a predetermined first threshold;
When the value corresponding to the voltage of the second power supply line is equal to or greater than a predetermined second threshold smaller than the first threshold and less than the first threshold, the first power is supplied to the second power supply line. , is determined to be the second state in which a voltage drop occurs,
9. When the value corresponding to the voltage of the second power supply line is less than the second threshold, it is determined that the first power is not normally supplied to the second power supply line in a third state. Or the end unit according to 9. further comprising a second power supply input terminal that receives a second power from the termination side of the plurality of IO units;
11. The end unit according to any one of claims 7 to 10, wherein a circuit forming said monitoring section operates with said second power.

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