JP2023046556A - Erroneous connection prevention device, and erroneous connection prevention method - Google Patents

Abstract

To provide a device and method that can simply prevent an erroneous connection even for a DC power source output terminal.SOLUTION: An erroneous connection prevention device of an electronic device comprises, for preventing an erroneous connection with respect to an external power source output circuit,: an external power source output interface to which a peripheral circuit is supposed to be connected, in which the peripheral circuit receives a power supply from the external power source output circuit connected to a power source line extending from the external power output circuit; an erroneous connection notification unit that, when an external power source is unintentionally connected to the external power source output interface connected to the power source line, gives notification indicative of the erroneous connection; a first opening/closing unit that is in an opening state when the power supply is not given to the electronic device provided in a route of the power source line, and is switched from the opening state to a closed state when the power supply is given thereto; and a second opening/closing unit that is in the closed state when the power supply is not given to the electronic device inserted and provided to/in the route linking between the power source line and the erroneous connection notification unit, gets switched to the opening state from the closed state when the power source is given thereto, and disengages the erroneous notification unit from the power source line.SELECTED DRAWING: Figure 1

Description

The present invention relates to an erroneous connection prevention device and an erroneous connection prevention method for reducing damage to equipment due to erroneous connection in connection with installation work of electronic equipment.

In general, a monitoring device or the like that monitors an external device such as a sensor device has an interface to which the external device is connected (hereinafter referred to as an external device interface) and an interface to which an external power supply is connected (hereinafter referred to as (referred to as an external power supply input interface). In such a monitoring device, if an external power source is accidentally connected to the external device interface to which the external device is to be connected, a voltage is applied to the internal circuit of the monitoring device, possibly damaging the internal circuit. Therefore, a technology has been proposed that can prevent damage to internal circuits by detecting erroneous connections.

Patent Document 1 discloses a technique for preventing damage to an external unit by turning on the external power supply switch of the external unit only when it is confirmed that the external unit is properly connected to a predetermined slot. .

The technique described in Patent Document 1 prevents damage to the external unit by associating the pre-registered identification number of the external unit with the identification number of the external unit connected to the slot. However, the technique described in Patent Document 1 may not be able to prevent damage to the external unit when using an external unit that does not have an identification number registered or an external unit that does not hold an identification number. be.

In contrast to such prior art, Patent Literature 2 discloses an erroneous connection prevention device having a function of effectively preventing damage to internal circuits of an electronic device due to erroneous connection.

The erroneous connection prevention device disclosed in Patent Document 2 includes an external device interface, an external power supply input interface, an erroneous connection annunciator connected to a signal line extending from the external device interface, and an external device interface. and an opening/closing portion provided in a path serving as a signal line connecting the internal circuit. The erroneous connection detection prevention unit outputs a signal indicating erroneous connection when an external power supply is erroneously connected to the external device interface. The opening/closing part is in an open state when the external power supply is not connected to the external device interface, and is switched from the open state to the closed state when the external power supply is connected to the external power input interface. The erroneous connection detection prevention unit includes an erroneous connection annunciator that notifies an erroneous connection.

In the erroneous connection prevention device disclosed in Patent Document 2, even if the external power source is erroneously connected to the external device interface, the opening/closing portion may be broken by connecting the external power source to the external power input interface in that state. It switches to the closed state. In other words, erroneous connection of the external power source to the external device interface and connection of the external power source to the external power input interface while ignoring the erroneous connection state may damage the internal circuitry of the electronic device. there were.

On the other hand, Patent Document 3 discloses an erroneous connection prevention device that solves this problem. The erroneous connection prevention device disclosed in Patent Document 3 has the same configuration as that of Patent Document 2, except that the operation of the opening/closing portion is different as described later. Specifically, the opening/closing portion is in an open state when the external power supply is not connected to the external power supply input interface, and switches from the open state to the closed state when the external power supply is connected to the external power supply input interface. , the open state is maintained even if the external power supply is connected to the external power supply input interface when receiving the signal indicating the incorrect connection.

JP-A-3-211630 Japanese Patent No. 6021208 Japanese Patent No. 6452174

The erroneous connection prevention device disclosed in Patent Document 2 outputs a signal indicating erroneous connection when the external power supply is erroneously connected to the external device interface, and when the external power supply is correctly connected to the external power input interface. , to switch the opening/closing part from the open state to the closed state. The erroneous connection prevention device that operates in this manner can prevent damage to the internal circuits of the electronic device even if an external power supply is erroneously connected to the external device interface.

In addition, the incorrect connection prevention device disclosed in Patent Document 3 prevents the external device interface even if the external power source is correctly connected to the external power source input interface and power is supplied to the internal circuit of the electronic device through the power line. While the external power supply is connected to the , the connection between the signal line connected to the internal circuit of the electronic device and the external device interface is cut off. The erroneous connection prevention device that operates in this manner can prevent damage to the internal circuits of the electronic device even if the external power source is erroneously connected to the external device interface and the external power source is properly connected.

The erroneous connection prevention devices disclosed in Patent Document 2 and Patent Document 3 prevent an external power supply from being erroneously connected to an input/output signal terminal that is an interface for an external device when an electronic device is installed or reinstalled (that is, "work error"). However, as a connection abnormality related to misconnection that can occur during similar construction work, electronic devices with external power output (external power (including the device) may be connected to an external power supply system.

If this erroneous connection is made, there is a possibility that the internal circuit of the electronic device or the erroneously connected electronic device that outputs an external power supply will be damaged.

For example, electronic devices such as security devices are frequently replaced due to location change, circuit change, or replacement. There are various types of electronic devices, some having terminals for outputting 24 V or the like for supplying power to external peripheral devices, and others having no terminals. Among them, there are devices that have similar appearance but different output voltages and devices that do not have silk printing. In addition, some electronic devices change the voltage to be output externally by setting.

If the DC power supply output terminal of an external device is mistakenly connected to the output terminal of an electronic device such as 24V during replacement, etc., current will flow from the higher potential to the lower potential, damaging the device through which the current flowed. There is

As a circuit for preventing damage to the device itself, there is a protection circuit that incorporates a diode in series with the output line (power supply line) of the device for blocking reverse source current. However, diodes have a power loss of V _F (forward voltage)×I _F (forward current) due to their forward voltage characteristics. For this reason, heat generation and power consumption of the diode are disadvantages as an electronic device.

There are various methods for connecting terminals of this type of electronic device, such as connecting various sensor devices with wired cables, connecting to terminals of other electronic devices, and connecting terminals of the same type of electronic devices in a daisy chain. . Electronic devices often perform one or a combination of the following to prevent erroneous connections to terminals. It should be noted that there are cases where the prevention of incorrect connection is not intended only by the instructions in the circuit design drawing.

・Indicate the name of the connection destination on the label or silk on the board
・Physically separate the terminal block for the power supply section and the sensor section
・Notation in the installation manual

However, in spite of these notations and warnings, damage may occur to electronic devices when incorrect wiring is performed during installation work. When replacing an electronic device, it is often the case that the external power source of the electronic device is connected to the output power source of another device, which tends to cause failures and malfunctions.

Therefore, for example, as disclosed in Patent Documents 2 and 3, it is conceivable to connect the erroneous connection detection prevention unit (erroneous connection reporting unit) connected to the signal line to the power supply line as well. However, if a misconnection detection prevention unit (misconnection alarm unit) is connected to the power supply line, the power switch can be turned on in a state where there is no misconnection to the power supply output terminal and the external power supply is normally connected to the external power supply interface. The problem is that the erroneous connection detection preventing unit (erroneous connection reporting unit) operates even when it is turned on.

SUMMARY OF THE INVENTION An object of the present invention is to provide an erroneous connection prevention device and method that can prevent erroneous connection to a DC power supply output terminal without problems.

An erroneous connection prevention device according to one embodiment of the present invention is an erroneous connection prevention device for preventing erroneous connection to an external power output circuit provided in an electronic device, and is connected to a power line extending from the external power output circuit. an external power output interface to which a peripheral circuit receiving power supply from the external power output circuit is to be connected; and an incorrect connection notification unit connected to the power supply line. , the erroneous connection annunciator that notifies an erroneous connection when an unintended external power source is connected to the first interface; the first opening/closing unit, the power supply line, and the erroneous connection reporting unit, which are in an open state when the electronic device is not supplied with power and are switched from the open state to the closed state when the power is supplied; a second opening/closing portion inserted into a second path connecting between the electronic devices, which is closed when power is not supplied to the electronic device, and changes from the closed state to the open state when power is supplied; and the second opening/closing unit that switches to disconnect the incorrect connection reporting unit from the power supply line.

An erroneous connection prevention method according to one embodiment of the present invention is a erroneous connection prevention method for preventing erroneous connection to an external power supply output circuit provided in an electronic device, and includes a power supply line extending from the external power supply output circuit. A misconnection notifying unit notifies misconnection when an unintended external power supply is connected to an external power supply output interface to which a peripheral circuit receiving power supply from the external power supply output circuit is connected. Simultaneously with switching the first opening/closing part provided on the first path serving as the line to the open state when the electronic device is not supplied with power and switching from the open state to the closed state when the power is supplied. a second opening/closing unit inserted into a second path connecting the power supply line and the misconnection notifying unit so as to be closed when power is not supplied to the electronic device; By switching from the closed state to the open state when there is power supply, the misconnection reporting unit is disconnected from the power supply line.

According to the present invention, it is possible to provide an erroneous connection prevention device and method that can prevent erroneous connection to a DC power supply output terminal without any problem.

1 is a block diagram showing the configuration of an erroneous connection prevention device according to a first embodiment; FIG. 1 is a block diagram showing the configuration of a monitoring device according to a first embodiment; FIG. FIG. 3 is a circuit diagram showing a specific configuration example of an incorrect connection reporting unit 13, a first opening/closing unit 14, and a second opening/closing unit 15 according to the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, in order to avoid complication due to repeated description, the same or corresponding parts in each figure are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.
[First Embodiment]

An erroneous connection prevention device 10 according to the first embodiment of the present invention will be described. FIG. 1 is a block diagram showing the configuration of the erroneous connection prevention device 10. As shown in FIG.

As shown in FIG. 1 , the erroneous connection prevention device 10 includes an external power supply output interface 11 , an erroneous connection reporting section 13 , a first opening/closing section 14 , and a second opening/closing section 15 . In addition, the erroneous connection prevention device 10 may include an external power supply input interface 12 as described later.

The external power supply output interface 11 is an interface that connects with an internal circuit (not shown), and is, for example, an external power supply connector. A device connected to the external power supply output interface 11 is not particularly limited, but is, for example, a sensor device.

On the other hand, the external power supply input interface 12 is an interface for connecting with an external power supply (not shown), and is, for example, an external power supply connector or a terminal block. The external power supply is not particularly limited, but is, for example, a power supply that outputs a DC voltage such as DC 12 V, DC 24 V, and DC 48 V, and has a higher voltage than the electrical signal given to the external power output interface 11. . The external power output interface 11 and the external power input interface 12 may have the same shape.

The incorrect connection notification unit 13 is connected to the external power supply output interface 11 via the second opening/closing unit 15, and when the external power supply is connected to the external power supply output interface 11, the power supply to the electronic device is interrupted. While there is no, it detects that it is a wrong connection. Specifically, the erroneous connection notification unit 13 notifies the erroneous connection by rectifying the output voltage of the external power supply erroneously connected to the external power supply output interface 11 and supplying it to the notification circuit (lamp or buzzer). Execute notification. The incorrect connection notification unit 13 operates because the second opening/closing unit 15 is closed while power is not supplied to the electronic device, but does not operate when the second opening/closing unit 15 is opened. As will be described later, such an incorrect connection notification unit 13 can be composed of, for example, a rectifier circuit such as a diode bridge and a notification circuit.

The first opening/closing unit 14 is provided in series with the power supply line between the external power supply output interface 11 and the internal circuit (external power supply output circuit) of the electronic device in which the incorrect connection prevention device 10 is mounted. It is connected to the power supply output interface 11 . The first opening/closing unit 14 is open when no power is supplied to the electronic device. It is closed by a control signal that governs opening and closing when supplied. As a method of discriminating whether or not power is supplied to the electric device (especially the external power output circuit), for example, the power switch of the electronic device may be interlocked, or the input of the external power output circuit may be monitored. You may make it discriminate|determine.

Since the first opening/closing part 14 is in an open state in the initial state when the power is not turned on, the external power supply output interface 11 and the internal circuit of the electronic device equipped with the erroneous connection prevention device 10 are electrically connected. separated. Further, when an external power supply is connected to the external power supply input interface 12, the first opening/closing part 14 is operated by the power of the external power supply, and switches from the open state to the closed state.

When the first opening/closing unit 14 is in the closed state, the external power output interface 11 and the external power output circuit of the electronic device in which the erroneous connection prevention device 10 is mounted are electrically connected. Then, when the external power source is removed from the external power input interface 12 and power is not supplied to the electronic device, the first opening/closing portion 14 switches from the closed state to the initial open state. Such a first opening/closing unit 14 can be composed of, for example, a relay, a field effect transistor, or the like.

The second opening/closing portion 15 is provided in parallel with the power supply line between the first opening/closing portion 14 and the external power output interface 11, and connects the erroneous detection detection portion 13 to the power supply line. The second opening/closing unit 15 is closed when no power is supplied to the electronic equipment. It will be in an open state by the control signal which controls opening and closing when supplied. As a method for discriminating whether or not power is supplied to the electric device (especially the external power output circuit), for example, the power switch of the electronic device may be interlocked, or the input of the external power output circuit may be monitored. You may make it discriminate|determine. The timing of switching the open/closed state of the second opening/closing portion 15 is interlocked with that of the first opening/closing portion 14 .

Since the second opening/closing unit 15 is closed in the initial state when no power is supplied to the electronic device, the external power output interface 11 and the incorrect connection notification unit 13 are kept electrically connected. . Further, when an external power supply is connected to the external power supply input interface 12, the second opening/closing part 15 is operated by the power of the external power supply and switches the state from the closed state to the open state. In other words, the conductive state/non-conductive state of the second opening/closing portion 15 and the first opening/closing portion 14 are alternately related. The second opening/closing unit 15 is closed when power is not supplied to the electronic device, and connects the erroneous connection notification unit 13 to the power supply line, and is open when power is supplied. The notification unit 13 is disconnected from the power supply line. Such a second opening/closing unit 15 can be configured by, for example, a relay, a field effect transistor, or the like.

The erroneous connection prevention device 10 includes a notification circuit that, when an external power supply is erroneously connected to the external power supply output interface 11, notifies the user or the like that the connection is erroneous. Although such a notification circuit is not particularly limited, it is preferable to configure it by combining, for example, an LED (Light Emitting Diode), an internal buzzer, an external signal output, or the like. A user or the like can easily notice that the connection to the external power supply output interface 11 is incorrect by activating the notification circuit at the time of incorrect connection.

FIG. 2 is a block diagram showing the configuration of the monitoring device 1. As shown in FIG. The monitoring device 1 includes the erroneous connection prevention device 10 shown in FIG. 1 and an internal circuit 20 including an external power supply output circuit.

The monitoring device 1 is an example of an electronic device in which the erroneous connection prevention device 10 is installed, and is a device that monitors a connected external device or the like. In this case, the internal circuit 20 is a circuit including, for example, a sensor interface. The internal circuit 20 also includes an external power output circuit for supplying power to an external device via the external power output interface 13 .

It should be noted that the description will be made assuming the monitoring device 1 having a signal terminal as the electronic device on which the incorrect connection prevention device 10 is mounted, but this is an example and does not limit the present invention. The erroneous connection prevention device 10 can be installed not only in the monitoring device 1 but also in various electronic devices.

As shown in FIG. 2, the external device 30 is connected to the external power output interface 11 in a normal connection. Also, in a normal connection, the external power supply 40 is connected to the external power supply input interface 12 . This connection is a normal connection, and power is supplied to the external device 30 using the power supplied from the external power supply 40 .

In the monitoring device 1 , an external power supply 40 connected to the external power supply input interface 12 supplies power for opening/closing the first opening/closing section 14 . In this case, the first opening/closing unit 14 operates by receiving drive power from the external power supply 40 and switches from the open state to the closed state. Further, the second opening/closing portion 15 operates by receiving drive power for opening/closing from the external power source 40, and switches the state from the closed state to the open state.

When the first opening/closing portion 14 is in the open state, the external device 30 connected to the external power output interface 11 and the internal circuit 20 are electrically separated. At this time, the second opening/closing unit 14 is closed, and the incorrect connection notification unit 13 is electrically connected to the external power supply output interface 11 .

By switching the state of the first opening/closing unit 14 to the closed state, the external device 30 connected via the external power output interface 11 and the internal circuit 20 are electrically connected, and the external device 30 is powered. supply is made. The state of the second opening/closing portion 14 at this time is the open state, and the incorrect connection reporting portion 13 is electrically disconnected from the external power output interface 11 (power output line).

On the other hand, if some external power supply is erroneously connected to the external power supply output interface 11, this external power supply supplies power to the incorrect connection notification section 13 if the second opening/closing section 15 is closed. In this case, the incorrect connection notification unit 13 operates by receiving power from the incorrectly connected external power source, and notifies the operator of the incorrect connection.

At this time, when the external power supply is not connected to the external power supply input interface 12 (when the internal circuit is not supplied with power), the first opening/closing part 14 is in the open state (non-conducting state) of the contact portion. state).

In this manner, the illustrated erroneous connection prevention device 10 notifies the operator by sound or light when the external power source 40 is erroneously connected to the external power output interface 11 . On the other hand, when the operator supplies power to the internal circuit 20 in the absence of notification (that is, the external power output interface 11 is not supplied with power), the false detection unit 13 is disconnected from the power output line, so the external power supply The external power output is performed normally without the notification being executed by the power from the output circuit.

Therefore, the operator can connect the external power source to the external power source input interface 12 while the external power source is erroneously connected to the external power source output interface 11 of the erroneous connection prevention device 10 (state of being notified). It is possible to prevent connecting the power supply.

FIG. 3 is a circuit diagram showing an example of the configuration of the monitoring device 1. As shown in FIG. A specific configuration of the monitoring device 1 will be described below with reference to FIG.

The external power output interface 11 has a + terminal 111 and a GND terminal 112 . A + terminal 111 is a terminal connected to a + input terminal (signal +) of an external device. The GND terminal 112 is a terminal connected to the -input terminal (signal-, GND terminal) of the external device.

The external power input interface 12 has an input terminal 121 and a GND terminal 122 . The input terminal 121 is a terminal connected to an output terminal of an external power supply. A GND terminal 122 is a terminal connected to a GND terminal of an external power supply.

The configuration of the external power supply output interface 11 and the external power supply input interface 12 shown in FIG. 3 is an example, and the number of terminals is not limited. A designer or the like may freely change the number of terminals of the external power supply output interface 11 and the external power supply input interface 12 according to the design.

The illustrated incorrect connection notification unit 13 includes a diode bridge 133 and a notification circuit 134 .

The diode bridge 133 is a rectifier circuit that rectifies the output voltage of the external power supply and supplies it to the notification circuit 134 when the external power supply is erroneously connected to the external power supply output interface 11 .

Specifically, the diode bridge 133 rectifies the output voltage of the external power supply when the + output terminal of the external power supply is connected to the + terminal 111 and the GND terminal of the external power supply is connected to the GND terminal 112 . The diode bridge 133 rectifies the output voltage of the external power supply even when the GND terminal 112 is connected to the +output terminal of the external power supply and the +terminal 111 is connected to the GND terminal of the external power supply.

When the external power supply is erroneously connected to the external power supply output interface 11, the notification circuit 134 notifies the operator or the like of the erroneous connection by means of a buzzer and an LED. It should be noted that the incorrect connection notification unit 13 (notification circuit 134) may be configured by appropriately combining an element for current limitation and an element for voltage adjustment together with an element for notification. Further, for example, when a change is made such as not providing the notification LED, fine adjustment of the circuit configuration may be made as appropriate, such as short-circuiting the notification LED portion. Further, a configuration may be adopted in which a signal indicating an incorrect connection is transmitted to the outside of the incorrect connection notification section 13 in parallel with the notification to the operator.

That is, if the external power supply is erroneously connected to the external power supply output interface 11 while the internal circuit 20 is not supplied with power, the illustrated misconnection notification unit 13 rectifies the output voltage of the external power supply to notify the circuit. 134 is activated to notify the operator of the erroneous connection.

It should be noted that the circuit structure of the incorrect connection reporting unit 13 shown in FIG. 3 does not limit the present invention to this structure. A designer or the like can appropriately change the configuration of the incorrect connection notification unit 13 according to the number of signal lines of the external power supply output interface 11, the connection pattern of the external power supply, the power supply voltage that may be connected, and the like. .

The first switching unit 14 is composed of an a-contact relay, and a movable contact is provided in series between the external power output interface 11 and the internal circuit 20 (external power output circuit 211) of the monitoring device 1 . The first opening/closing part 14 is interlocked with power supply to the internal circuit 20 and is in an open state when the external power supply is not connected to the external power supply input interface 12 . On the other hand, the first opening/closing portion 14 is closed when the external power supply is connected to the external power supply input interface 12 and the switch SW is turned on. That is, the opening/closing control of the first opening/closing portion 14 is linked to the power supply to the internal circuit 20 .

The second opening/closing unit 15 is composed of a b-contact relay, and the internal circuit 20 (external power output circuit 211) of the monitoring device 1 is provided with the external power output interface 11 and a movable contact in parallel. The second opening/closing part 15 is interlocked with power supply to the internal circuit 20 and is closed when the external power supply is not connected to the external power supply input interface 12 . On the other hand, the second opening/closing unit 15 is opened when the external power supply is connected to the external power supply input interface 12 and the switch SW is turned on. In other words, the opening/closing control of the second opening/closing portion 15 is also interlocked with the power supply to the internal circuit 20 , and is interchangeable with the opening/closing state of the first opening/closing portion 14 .

Note that the circuit configuration using the voltage conversion unit 123 and the switch SW in FIG. 3 is an example, and the position of the switch SW and the presence/absence of the voltage conversion unit 123 may be appropriately changed according to the design policy. For example, the circuit shown in FIG. 3 assumes an external DC power supply, but in order to use a commercial power supply, an AC-DC conversion circuit may be adopted, or a circuit configuration using an AC adapter may be adopted. The circuit configuration may be adapted to both the current and the DC.

In the circuit of FIG. 3, when the external power supply is normally connected to the external power supply input interface 12 and the switch SW is turned on, the first opening/closing section 14 and the second opening/closing section 15 are opened and closed, respectively. is switched. At this time, if the external power supply is erroneously connected to the external power supply output interface 11, since the notification circuit 134 is in operation, the operator or the like will not switch or make new connections. will not be supplied.

In FIG. 3, the first opening/closing portion 14 and the second opening/closing portion 15 are shown using relays, but the relays are examples for facilitating the explanation, and the circuits of the relays are transistors or the like. It is also possible to configure by combining switching elements.

The voltage converter 123 steps up/down the output voltage of the external power supply normally connected to the external power supply input interface 12 . Such a voltage converter 123 can be configured by, for example, a DC-DC converter, a chopper circuit, or the like. When the external power supply is normally connected to the external power supply input interface 12, the first opening/closing part 14 and the second opening/closing part 15 connected to the voltage conversion unit 123 switch the state as described above and output the external power supply. The interface 11 and the external power supply output circuit 211 are electrically connected.

With the circuit configuration described above, the notification circuit 13, the first opening/closing unit 14, and the second opening/closing unit 15 can prevent the internal circuit 20 of the monitoring device 1 from being connected to the internal circuit 20 even if the first external interface 11 is erroneously connected to the external power supply. It is configured to notify a worker or the like of an erroneous connection to the DC power supply output terminal even when power is not being supplied.

In other words, this circuit configuration extracts power from the diode bridge, drives the LED and buzzer, and informs the operator of the abnormal state without supplying power from the electronic device when there is an erroneous connection to the external power output interface 11. Equipped with a configuration for immediate notification. On the other hand, the opening/closing control of the first opening/closing portion 14 and the second opening/closing portion 15 that are interlocked with the power supply state of the internal power supply 20 is realized only by hardware. That is, it is possible to more firmly prevent damage to the circuit of the electronic device due to incorrect connection of the DC power supply output terminal.

When the external power supply that may be connected to the external power supply output interface 11 (+terminal 111, GND terminal 112) is defined as a 24V power supply, the circuit element required for notification is a resistor R1 (5 [KΩ]) , Zener diode D2 (Vz=6 [V]). For the Zener diode D1, a Zener diode having a value matching the required voltage of the buzzer may be selected. Similar values are used when including a 36V power supply for an external power supply that may be misconnected. If a higher voltage is assumed, the resistance value of R1 may be set higher, each element with a high withstand voltage may be used, or a resistor for voltage division may be inserted as appropriate.

In addition, by mounting the above-mentioned erroneous connection prevention device on each other of the electronic devices to be connected, that is, by forming an erroneous connection prevention system, the erroneous connection prevention device can mutually prevent troubles due to erroneous connection of the external output power supply by the operator. Can be configured. This is because when an electronic device on either side can supply power to an interface that is erroneously connected, even if power is not being supplied to the internal circuit of the counterpart device, the counterpart electronic device detects the erroneous connection. This is because an erroneous connection is notified at this time. Also, at this time, none of the electronic devices break down, and the connections can be reconnected.

REFERENCE SIGNS LIST 1 monitoring device 10 erroneous connection prevention device 11 external power output interface 12 external power input interface 13 erroneous connection reporting unit 14 first opening/closing unit 15 Second opening/closing unit 20 Internal circuit 111 + terminal 112 GND terminal 121 Input terminal 122 GND terminal 123 Voltage converter 133 Diode Bridge 134 ... notification circuit

Claims (4)

An erroneous connection prevention device for preventing erroneous connection to an external power supply output circuit provided in an electronic device,
an external power output interface connected to a power line extending from the external power output circuit, the external power output interface to be connected to a peripheral circuit receiving power supply from the external power output circuit;
an erroneous connection notifying unit connected to the power supply line, the erroneous connection notifying unit for notifying an erroneous connection when an unintended external power supply is connected to the external power supply output interface;
A first opening/closing part provided on the first path serving as the power supply line, which is in an open state when the electronic device is not supplied with power, and is switched from the open state to the closed state when the power is supplied. the first opening/closing part;
A second opening/closing unit inserted into a second path connecting the power supply line and the misconnection reporting unit, the second opening/closing unit being in a closed state when power is not supplied to the electronic device, and a power source. a second opening/closing unit that switches from a closed state to an open state when there is a power supply to disconnect the incorrect connection reporting unit from the power supply line;
misconnection prevention device. 2. The erroneous connection prevention device according to claim 1, wherein the erroneous connection reporting section uses a buzzer and/or a lamp to report the erroneous connection. An erroneous connection prevention method for preventing erroneous connection to an external power supply output circuit provided in an electronic device,
An erroneous connection reporting unit connected to a power supply line extending from the external power supply output circuit detects that an unintended external power supply is connected to an external power supply output interface to which a peripheral circuit receiving power supply from the external power supply output circuit is to be connected. When the
At the same time, the first opening/closing portion provided on the first path serving as the power supply line is in an open state when power is not supplied to the electronic device, and is switched from an open state to a closed state when power is supplied. in parallel,
A second opening/closing part inserted into a second path connecting the power supply line and the misconnection notifying part is closed when power is not supplied to the electronic device, and the power is not supplied. disconnecting the misconnection notification unit from the power supply line by switching from the closed state to the open state when there is
Misconnection prevention method. 4. The erroneous connection prevention method according to claim 3, wherein the erroneous connection reporting section uses a buzzer and/or a lamp to report the erroneous connection.

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