JP5550062B2 - Outlet with grounding electrode - Google Patents

Description

The present invention relates to an outlet with a ground electrode. In particular, the present invention relates to an outlet with a grounding electrode that can easily determine whether or not a grounding system in an electric circuit is functioning normally.

Conventionally, the protection of wiring when overcurrent or short-circuit current flows in the circuit, the electric fire in the case where a ground fault occurs due to the deterioration of the insulation of the circuit or the load device, and the insulation of the load device as well As a result of the deterioration of the battery, a potential is generated between the earth and the casing that constitutes the load device, and various electrical accidents such as electric shocks that may occur when the human body touches the load device cause human life and property damage. In order to ensure safety, various power distribution devices have been developed, including wiring breakers and earth leakage breakers.

In particular, in order to prevent electrical accidents caused by the electric shock of the human body, the installation of earth leakage circuit breakers was obligated by the Industrial Safety and Health Regulations in 1969, and the number of deaths due to electric shocks has been decreasing year by year.

In order to distribute power to the load circuit, these various types of power distribution equipment are housed in cabinets, and distribution boards incorporating power distribution equipment inside the cabinets have traditionally been used in factories and homes. It is used.

Well, it is well known that even before the installation of earth leakage circuit breakers became mandatory, protective grounding of equipment was carried out from the viewpoint of preventing electric shock accidents, and results were achieved in preventing electric shock accidents in the human body. It is.

For example, as shown in FIG. 21, even when the insulation of the load equipment installed in the electric circuit is deteriorated and the ground voltage _Vg is generated between the ground and the housing of the load equipment, the ground resistance has no influence on the human body. Is as follows.

The R _B B type grounding resistance, represented the _{R D} D type grounding resistance, the _{V E} as path _{voltage, V g = {R D /} (R B + R D)} V E ··· ( Equation 1) and . Here, assuming that the resistance of the human body is 1 kΩ and the human body passage allowable current is 30 mA, which is limited to several minutes (electric shock current by Mr. Biegelmeier and the physiological response of the human body), the ground voltage is V _g = 30V. It is considered the upper limit of tolerance.

When path voltage _{V E} is 200V, by calculating by substituting _{V g} in Formula _{1, R B = 5.7R D ···} ( Equation 2), and the B type grounding resistance magnitude 10Ω In this case, since R _D ≈1.7Ω, the D-type ground resistance may be set to about 1.7Ω or less.

However, this ground resistance of 1.7Ω or less is a low ground resistance value that is practically difficult to obtain by ordinary grounding work. Even when the ground resistance is obtained using a ground resistance reducing agent that uses, for example, an inorganic high water content crystal, the ground resistance is maintained over time. It is necessary to check whether it has been struck, and it is actually difficult to check the grounding resistance over the years because the surrounding environment often changes from when the grounding work was performed. It was a thing.

In this way, electrical accidents due to electric shock from human bodies have been conventionally prevented by protective grounding of equipment, but in addition to grounding, by installing the above earth leakage breaker in the electrical circuit, If the insulation of the battery deteriorates and a leakage current of a predetermined magnitude occurs in the circuit, the leakage circuit breaker interrupts the circuit, eliminating the risk of electric shock, and can be more effectively prevented. Is. However, even if the earth leakage circuit breaker is installed in the circuit, if the grounding work is not sufficient, the time between the contact of the human body with the load equipment whose insulation has deteriorated and the operation of the earth leakage circuit breaker is interrupted. In this case, the leakage current will flow through the human body, and the possibility of an electric shock accident cannot be completely denied.

Thus, grounding is very important for ensuring the safety of human lives and property from various electrical accidents regardless of the presence or absence of the earth leakage breaker.

In view of the importance of such grounding, the above-described distribution board is also provided with a ground branch line terminal for connecting the wiring of the ground electrode, that is, the ground branch line. For example, “Japan Wiring Equipment Industry Association Standard JWDS 0007 Housing The structure is described in “Distribution panel”.

In addition, as for the distribution board provided with such a ground wire branch terminal, for example, a distribution board provided with a ground relay terminal as shown in Patent Document 1 (FIG. 1) and Patent Document 2 (FIG. 4). It is known.

By the way, when the grounding work is performed, the grounding resistance, that is, the resistance between the ground and the grounding electrode which is an electrical terminal provided on the ground, depends on the kind of grounding work. It is necessary to check whether or not a predetermined resistance value is satisfied.

The grounding work is as described in “Technical Standards for Electrical Equipment”. According to Article 19 of the Interpretation of Technical Standards,
“Grounding work shall be conducted in accordance with Article 13 [Insulation of electrical circuits] No. 6 and No. 7 (a), Article 23 [Grounding of service entrances], Article 28 [Electrical equipment grounding] ] Paragraphs 1, 2 and 4 and Article 42 [Grounding of lightning arresters] When grounded under the provisions of Nos. 2a, 3a, b), and the same high voltage overhead wire as the special high voltage overhead wire Except for the case where grounding work is performed on the parts to be installed on the support, the following four types are listed in the left column, and the grounding resistance value in each grounding work depends on the type of grounding work listed in the left column of the table. According to the type of each grounding work, the grounding resistance value is 10Ω in the case of Class A grounding work, and in the case of Class B grounding work. Is the amperage of the 1-wire ground fault current of the high-voltage side or extra high-voltage side of the transformer (150 When the ground voltage of the low piezoelectric circuit exceeds 150 V due to the contact between the extra high voltage circuit and the low voltage circuit, the operating voltage is less than 35,000 V, and the high voltage circuit is automatically used within 2 seconds. 300 when installing a device that cuts off a special high voltage circuit with a voltage of 35,000 V or less, and 600) when installing a device that automatically cuts off a high voltage circuit within a second or a voltage of 35,000 V or less. In the case of class C grounding work, the number of ohms equal to the divided value is 10 Ω (when installing a device that automatically shuts off the electric circuit within 0.5 seconds when grounding occurs on the electric circuit in a low piezoelectric circuit) 500Ω), and in the case of Class D grounding construction, 100Ω (500Ω when installing a device that automatically cuts off the electric circuit within 0.5 seconds when grounding occurs on the electric circuit in a low piezoelectric circuit) ) And the ground resistance value.

As a method for measuring the ground resistance value, the following method has been proposed conventionally.

First, in addition to the grounding electrode for measuring the desired grounding resistance, two auxiliary electrodes are used, and each electrode is placed in the soil at intervals of several meters so that it becomes the apex of the triangle. This is a so-called Kolash Bridge method in which the target ground resistance is measured by measuring the resistance between vertices.

Second, in addition to the ground electrode that measures the desired ground resistance, two auxiliary electrodes are used, each electrode is placed in a straight line in the soil, and the desired ground resistance is measured at one end. A ground electrode is disposed, one auxiliary electrode is installed at the other end separated by several tens of meters, the other auxiliary electrode is disposed between the ground electrode and the other auxiliary electrode, and the other end is disposed. This is a so-called electrode voltage drop method in which a target ground resistance is measured by passing a current between the auxiliary electrode and the ground electrode and measuring a voltage generated between the other auxiliary electrode and the ground electrode.

Third, without using an auxiliary electrode, several tens of meters of wire is routed on the ground, and the capacitor component formed between the wire and the ground and the inductance component present in the wire are used to achieve the target. By applying a high-frequency signal via a known resistance between the ground electrode for measuring the ground resistance and the electric wire, the capacitor component and the inductance component are canceled by resonating, and the high-frequency voltage at resonance and the terminal This is a method using so-called resonance in which the ground resistance is measured by measuring the voltage.

However, in these measurement methods, it is necessary to drive each auxiliary electrode used for measurement into the soil, and to arrange each electrode on a triangle or a straight line with a certain distance, and therefore, between the electrodes. The distance and the length of the wire used for measurement are several tens of meters. Actually, it is necessary for measurement because the surroundings to be measured are paved with concrete or asphalt, and the neighbors and fences are installed. In many cases, it is difficult to measure the ground resistance.

In addition, it is necessary to drive each auxiliary electrode used in the measurement into the ground, and to place each electrode on a triangle or straight line with a distance of several tens of meters. Was very laborious and labor intensive.

Based on the importance of grounding and the effort of measuring grounding resistance, the technology for adjusting the grounding resistance value to fall within the specified range and the measurement at places where grounding resistance measurement is difficult have been improved. Patent Documents 3 to 5 disclose techniques for improving work efficiency.

FIG. 19 shows an example of a wiring tester in Patent Document 6 (FIG. 7). The idea of Patent Document 6 was made in view of providing a wiring tester capable of quickly and surely performing a wiring confirmation inspection after construction,
A power supply voltage insertion blade that can be connected to the power supply voltage electrode and a power supply voltage insertion blade that can be connected to the power supply voltage electrode, and a grounding connection that can be connected to the grounding electrode. An insertion blade, a power supply grounding insertable blade connectable to the power supply grounding electrode, a first rectifier element having one terminal connected to the power supply voltage insertion blade, and one terminal for the grounding A second rectifying element connected to the insertion blade; a first display circuit connected to the other terminal of the first rectifying element; and the other terminal of the second rectifying element; A second display circuit connected to the power insertion blade and the other terminal of the second rectifying element; and a power supply grounding blade connected to the other terminal of the first rectifying element. Third
An example in which a wiring tester is configured to include the display circuit is disclosed.

FIG. 20 shows a polarity check device for an outlet with a ground electrode in Patent Document 7 (FIG. 1). Patent Document 2 discloses an apparatus for checking whether a grounding electrode is grounded and whether there is a connection error. The device uses a combination of a master unit and a slave unit. The master unit is configured with current detection means that detects the current flowing in the zero phase or the ground wire of the outlet, and the slave unit is connected to the outlet to be checked, and the outlet voltage and ground poles are connected from the slave unit side. Whether the grounding electrode is grounded based on whether or not the current detecting means has detected current according to the pole from which the current is passed from the slave unit on the parent side. An apparatus for checking for connection errors is disclosed.

JP 2000-201202 A Japanese Patent Laid-Open No. 2000-201407 JP 2006-275623 A JP 2007-163139 A JP 2007-127558 A Registered Utility Model No. 3128286 JP 2006-38707 A

However, an apparatus for simply confirming the grounding resistance after the grounding work has been performed is not disclosed, and the work for measuring the grounding resistance requires labor as described above. In addition, even if the grounding work itself is done properly, the grounding system is connected to the electrical terminal provided on the ground where the grounding wire in the above-mentioned electric circuit is connected, and also in the part of the outlet that supplies power to the electrical equipment. Since it functions for the first time when the grounding wire is normally connected, it is important to confirm whether the grounding system is functioning as well as the grounding resistance.

Moreover, the grounding resistance is expected to change depending on the environmental conditions around the grounding system over time. Considering the deterioration of functionality due to aging of various connection parts in the grounding system, It is desirable to be able to easily check whether the grounding system is continuously functioning from time to time.

In addition, the wiring tester as in Patent Document 6 needs to be used by inserting the wiring tester into all outlets in the office as described in paragraph [0037] of Patent Document 6 in use. is there. For this reason, it is necessary to prepare as many outlets as possible before conducting the wiring confirmation inspection. Also, during the inspection, it is necessary to make sure that the tester is inserted into all outlets and turned around so as not to forget to insert the tester. In this way, the configuration of the tester itself is simple and inexpensive, but it requires a lot of confirmation tests, and it is necessary to prepare as many outlets as the number of outlets at the test site. It was not easy to confirm the grounding.

In addition, when using a combination of a master unit and a slave unit as in Patent Document 7, a current detection means is installed on the ground wire connected to the outlet, and after connecting the slave unit to the outlet, It was necessary to check whether the grounding electrode was grounded by passing a current through each of the grounding electrodes. As described above, it was not easy to check the grounding on a daily basis.

In the first place, if no ground wire is connected to the ground terminal, current cannot be detected by the current detection means on the master side even if current is passed from the slave unit to each of the voltage electrode and ground electrode. For users, it is not immediately known whether there is a problem with the outlet or the check device itself, and in order to grasp the cause, it is necessary to remove the outlet from the construction material and check the back side. It took time and effort to investigate the failure point.

In addition, in general, the grounding wire is on the grounding terminal side of the outlet, that is, the side opposite to the part where the plug is inserted into the construction material to which the outlet is attached. It is provided on the surface to be connected. For this reason, when the construction contractor connects the wiring, whether or not the grounding wire is connected can be confirmed by checking the back of the outlet, and in the situation where the display part cannot be seen, the connection is made audibly. Although completion indication can be done, after construction, if you try to check whether the grounding wire is connected to the grounding terminal, you can check the voltage phase by removing the outlet from the construction material and looking at the back. It was necessary to check whether the earth terminal was electrically connected to the ground wire by connecting a neon lamp or the like between the ground and the ground phase, and it was not easy to check the ground on a daily basis. .

In addition, after the completion of construction, it is necessary to check the wiring connection before supplying commercial power. In such a case, it is not possible to check visually from the front side of the outlet. In addition, after attaching the outlet to the construction material, it was impossible to confirm whether or not the grounding wire was connected to the grounding terminal simply by visual inspection.

Therefore, in view of the above-mentioned problems, the invention of the present invention determines whether the grounding system is functioning normally after the grounding work and the electrical wiring work are performed at the position of the outlet for supplying power to the electrical equipment. Check whether it is functioning properly from the side where the plug is inserted, on a daily basis, without bothering and at the position where it can be easily seen from the side where the plug is inserted, without the need for a commercial power supply even during construction. The purpose is to provide an outlet with a grounding electrode that can quickly identify the failure point and isolate the cause when a failure is expected in the grounding system.

In order to achieve the above-mentioned object, according to claim 1 of the present invention, the neutral wire side of the secondary winding of the transformer interposed in the electric circuit is grounded by a first electrical terminal provided on the ground, and A grounding system provided to supply power to the electrical equipment by connecting the grounding system in the load-side electrical circuit of the transformer to the electrical circuit grounded by the second electrical terminal provided on the ground via a centralized grounding terminal. An outlet with a pole, and a grounding terminal to which a grounding wire of an electric circuit is connected is provided on the back side which is the inner side of the construction material of the outlet. In the load-side electric circuit of the transformer, a voltage applying unit that applies a voltage between the voltage line or neutral line in the electric circuit and the grounding system, and a voltage applied by the voltage applying unit, In between A current detection unit for detecting a current to be detected; and when the current detection unit detects a current, it is determined that the grounding system is connected, and when the current is not detected, the grounding system In addition, a judgment part is provided to judge that the connection of the electrical plug is not made, and at least the grounding terminal of the electrical device is connected to the grounding terminal on the surface side into which the blade of the plug of the outlet plug is inserted. And a determination state identification unit that is connected to the determination unit and is arranged so that the determination state is visible from the side into which the plug of the outlet is inserted. It is possible to identify the plug from the side where the plug is inserted, and to provide an outlet with a grounding electrode.

According to such a configuration, the grounding system is connected by detecting the current generated by applying a voltage between the neutral line in the electric circuit and the grounding system at the place where the outlet is installed. Since the judgment status identification unit is arranged so as to be visible from the side where the plug is inserted, the judgment status can be identified from the side where the plug is inserted. Whether or not a grounding wire is connected to the grounding terminal can be checked on a daily and trouble-free basis from the side where the plug is plugged into the outlet, and a problem can be expected in the grounding system. In this case, it is possible to quickly grasp the failure point and isolate the cause.

According to a second aspect of the present invention, an outlet with a grounding electrode measures the voltage between a neutral line in the electric circuit and a grounding system in the load side electric circuit of the transformer, instead of the judging means according to the first aspect. When the voltage measured by the voltage measuring unit and the voltage measuring unit with respect to the line voltage between the neutral wire of the secondary winding of the transformer and the ground wire is approximately zero volts And determining means for determining that the grounding system is connected and, when the measured voltage value is not substantially zero volts, determining that the grounding system is not connected. The outlet with a grounding electrode is provided as a feature.
According to this configuration, it is possible to determine whether or not the grounding system is connected by detecting the voltage between the neutral line and the grounding system in the electric circuit.

According to a third aspect of the present invention, an outlet with a grounding electrode is a voltage for measuring a voltage between a voltage line in the electric circuit and a grounding system in the load-side electric circuit of the transformer, instead of the judging means according to the first aspect. When the voltage is measured by the measuring unit and the voltage measuring unit, the voltage values measured with respect to the line voltage between the neutral line and the voltage line of the secondary winding of the transformer are substantially equal voltage values. A determination unit that determines that the grounding system is connected, and determines that the grounding system is not connected when the measured voltage values are not substantially equal to each other. And providing an outlet with a grounding electrode.
According to this configuration, it is possible to determine whether or not the ground system is connected by detecting the voltage between the voltage line in the electric circuit and the ground system.

Also, outlets of the ground Kiwametsuki of claim 4, in the determination unit, provided the connection state switching unit for selectively switching the connection between the voltage line or neutral line said determining means is connected, according to claim 2 Alternatively , the present invention provides an outlet with a grounding electrode, characterized in that a determination unit for selectively or merging the determination by the determination unit according to claim 3 is provided.
According to this configuration, measurement data of various voltage values or current values necessary for making a determination by the determination unit is transmitted to the connection state switching unit between the voltage line and the ground system or the neutral line and the ground system. It can be obtained simply by selectively switching the connection. In the environment where the grounding system is provided, grounding in various surrounding environments is predicted as described above. Therefore, when checking the connection state of the grounding system, the connection state of the grounding system can be determined by one measurement method. Assuming the case of checking and the case of combining various measurement methods in advance, the ground line branch terminal is equipped with a configuration for performing multiple measurements, so that the connection status of the grounding system can be achieved by one measurement method. Even if it is difficult to check the connection, it is possible to check the connection status appropriately by using other measurement methods.

According to a fifth aspect of the present invention, there is provided an outlet with a ground electrode, wherein the judging means is interposed between the ground terminal and the earth terminal, and the switch means for switching on and off the electrical connection between the earth terminal and the earth terminal. The determination means is provided with a determination unit for selectively or merging the determination by the determination unit according to claim 2 or 3 in each of the on state and the off state. As an outlet with a grounding electrode.
According to this configuration, the switching unit controls the electrical connection between the ground terminal and the earth terminal, thereby creating a ground state and a non-ground state, and comparing the current value or voltage value in each state. By doing so, it is possible to determine whether or not the grounding system is connected more accurately, and it is possible to check the connection state of the grounding system, even though it is a very simple method, and it is possible to anticipate a failure in the grounding system. In this case, it becomes possible to quickly grasp the failure point and isolate the cause.

According to a sixth aspect of the present invention, in the outlet with a grounding electrode, the judgment state identification unit is provided on a mounting frame for fixing the outlet to the construction material so that the judgment state can be identified from the side where the plug is inserted. It is characterized by that.
According to this configuration, even when the determination state identification unit cannot be provided on the outlet itself, the determination can be identified with good visibility by being provided on the mounting frame near the outlet.

The outlet with a grounding electrode according to claim 7 is provided on the plate frame fixed to the mounting frame so that the judgment state identifying unit surrounds the embedding hole provided when the outlet is fixed to the construction material. A receptacle with a grounding electrode is provided, which is characterized in that the judgment state can be identified from the side into which the plug is inserted.
According to this configuration, even when the determination state identification unit cannot be provided in the outlet itself, it is possible to identify the determination with high visibility by providing it in the plate frame near the outlet.

Further, in the outlet with a grounding electrode according to claim 8, the judgment state identification unit is provided on a decorative panel attached to the plate frame on the opposite side to the construction material with respect to the plate frame, and the judgment state identification is inserted. It is characterized in that it can be performed from the plug insertion side.
According to this configuration, even when the determination state identification unit cannot be provided on the outlet itself, it is possible to identify the determination with high visibility by providing it on the decorative frame near the outlet.

Further, the outlet with the grounding electrode according to claim 9 is configured such that when the surface into which the plug of the outlet plug is inserted is the front surface and the surface to which the grounding wire is connected is the rear surface, In the decorative panel, a hole or a translucent part is provided in a front portion of the judgment state identification unit so that the judgment state identification unit is visible from the outside on the side where the plug is inserted. It is.
According to this configuration, even when the determination state identification unit cannot be provided in the outlet itself, the determination can be identified with high visibility by the frame portion near the outlet.

According to a tenth aspect of the present invention, there is provided an outlet with a ground electrode, wherein the ground line connection state determination unit and the determination state identification unit are provided with wireless communication units, respectively, and the ground line connection state determination unit and the determination state identification unit The communication is performed wirelessly, and the determination state identification unit is configured to be visible from the outside on the side where the plug is inserted.
According to this configuration, the ground line connection state determination means and the determination state identification unit can be configured without a wired connection, and the degree of freedom of installation of the determination state identification unit is further increased. Judgment can be identified with good visibility.

According to the present invention, after the grounding work and the electrical wiring work are performed, whether or not the grounding system is functioning normally is determined from the position of the outlet for supplying power to the electrical equipment and from the side where the plug is inserted. Whether or not it is functioning normally can be checked on a daily basis, without any trouble, at a position where it can be easily seen from the side where the plug is inserted into the outlet without the need for a commercial power supply even during construction. When a failure is expected in the system, it is possible to provide an outlet with a grounding electrode that can quickly identify the failure point and isolate the cause. The ground wire connection status judgment means is driven by the insertion force when the ground wire is connected to the outlet as a trigger, so it does not necessarily require a commercial power source to identify the judgment status at the time of construction or after the start of use. It is possible to configure an outlet provided with a ground line connection state determination unit that consumes less energy.

The external view of the outlet socket with a ground electrode and the insertion plug in the first embodiment is shown. The attachment figure to the construction material of the outlet socket with a ground electrode in 1st embodiment, and a schematic block diagram are shown. The figure which shows the 1st example of a judgment means. The figure which shows the 3rd example of a judgment means. The figure which shows the 4th example of a judgment means. The figure which shows the 5th example of a judgment means. The figure which shows the 7th example of a judgment means. The block block diagram of a ground line connection state judgment means is shown. The other block block diagram of a ground line connection state judgment means is shown. The schematic of the electrical storage part in a frame part is shown. The other block block diagram of a ground line connection state judgment means is shown. Display example using liquid crystal. Other display examples using liquid crystal An example in which a mechanical display unit is provided. The block diagram of a mechanical display part. The block diagram of a mechanical display part. The block diagram of a mechanical display part. The block diagram of a mechanical display part. The figure which shows a prior art example. The figure which shows a prior art example. Illustration of ground resistance

Embodiments of the present invention will be described below with reference to the drawings.
In all of the embodiments, the neutral line side of the secondary winding of the transformer interposed in the electric circuit is grounded by the first electric terminal provided on the ground, and the grounding system in the load-side electric circuit of the transformer is This shows an outlet with a grounding electrode that is connected to an electrical circuit grounded by a second electrical terminal provided on the ground via a central grounding terminal and is used to supply power to electrical equipment. .

It is assumed that a distribution board is provided on the load side of the transformer secondary winding, and that grounding is performed from a centralized ground terminal provided on the distribution board. In addition, an outlet with a grounding electrode is provided in the load-side circuit of the branch switch in the distribution board to supply power to various electrical equipment, and the grounding wire connected to the outlet is electrically connected to the centralized grounding terminal. Are connected to form a grounding system.

Also, in this application, as defined in JEAC8001, an extension regulation electrical equipment usage facility edition published by the Japan Electric Association, a neutral wire is a wire connected to the neutral pole of a power source of a multi-wire circuit. A neutral wire or a grounded wire that is grounded according to technical requirements in the low piezoelectric path is called a grounded electric wire. For example, the neutral wire of the secondary winding of the transformer is the ground side electric wire, and in the single-phase three-wire circuit, there are L1 and L2 poles as voltage poles and N poles as neutral poles. . In a single-phase two-wire circuit, there is a grounding side wire that is grounded to the voltage electrode.

In each embodiment described below, the number of plugs that can be plugged into the outlet is exemplified as two. However, the present invention can be applied to various things such as only one or three or more. Also good.

(Embodiment 1)
(Outline of outlet with grounding electrode)
First, an outline of the outlet with a ground electrode according to this embodiment will be described.
The outlet with a grounding electrode is an outlet that is embedded and attached to a construction material 40 that constitutes a wall surface and the like and is inserted by inserting the insertion plug 2 as shown in FIG. The outlet 1 is connected to electrical wiring disposed inside the construction material 40, and is used by inserting the plug 2 from the outside. Moreover, the electrical wiring connected to the outlet inside the construction material 40 is electrically connected to a branch switch provided in the distribution board.

Further, as shown in FIG. 2, the outlet 1 includes the mounting frame for embedding and attaching the outlet to the embedded hole provided in the construction material 40 in advance, and the mounting so as to surround the embedded hole. A plate frame 20 fixed to the frame, and a decorative frame 30 attached to the plate frame 20 on the side where the plug is inserted into the construction material 40 are provided.

The outer wall of the outlet 1 is constructed so as to be compatible with general outlets, and a connecting terminal for connecting electric wires of a voltage electrode, a neutral electrode, and a ground electrode to the inner surface of the construction material in the outlet. And a plug blade holder that is electrically connected to each of the voltage electrode, the neutral electrode, and the ground electrode, and into which the plug with the ground electrode is inserted, on the outer surface of the construction material. And a plug blade insertion hole. A determination state identification unit 100 that can identify a determination state as to whether or not the grounding system is functioning normally is provided on the outer surface of the construction material so as to be visible from the outside. Here, the connection terminal provided on the inner surface of the construction material in the outlet and connected to the ground phase wire is the ground terminal 101, and provided on the outer surface of the construction material in the outlet and the ground terminal 101. A connection terminal that is electrically connected to connect a ground wire of the electric device is the earth terminal 102. The earth terminal is configured with a plug blade holder so that the grounding electrode of the plug can be plugged in. In addition, when the grounding electrode of the plug is constituted by an electric wire, the earth terminal may be constituted by a screw terminal so that the electric wire of the grounding electrode can be connected.

About the connection terminal provided in the surface which becomes the inner side of the construction material in an outlet, the connection part is comprised by the quick connection type terminal generally used with the wiring device. The quick-connection terminal includes a terminal plate that is brought into contact with an electric wire to be connected, a locking spring that presses the electric wire against the terminal plate, and a conductor disposed around the chain spring. Connection with the electric wire is made by inserting the electric wire into the electric wire insertion hole provided in the body of the outlet, and the electric wire is placed between the chain spring arranged inside the electric wire insertion hole and the terminal plate. The wire is pressed against the terminal board by the elasticity of the chain spring and enters a conductive state. The same applies to the connection portion of the ground terminal 101.

Next, determination means for determining whether the grounding state is normal will be described with reference to FIGS.
(First example of judgment means)
FIG. 3 shows a first example of the determination means in the outlet 1 with the ground electrode of the present invention.

In FIG. 3, the neutral wire 5102 of the secondary winding of the transformer 5100 interposed in the electric circuit is grounded to the electric terminal (earth electrode) 5103 provided on the ground 5001 by the grounding wire 5102 a and connected to the load side of the electric circuit. The concentrated ground terminal 5601 provided on the distribution board 5700 is grounded to the electrical terminal 5203 similarly provided on the ground 5001 by the ground line 5202. In addition, an outlet 1 is connected to the load side of the branch switch of the distribution board, and a voltage electrode, a neutral electrode, and a ground wire connected to the centralized ground terminal 5601 are connected to the outlet. The ground wire connected to the outlet 1 is grounded to the ground via a central ground terminal 5601 and connected to the neutral wire of the secondary winding of the transformer 5100 via the ground 5001 to form a grounding system. ing.

The judging means judges whether or not the state of such a grounding system is functioning normally. A voltage is applied between the neutral line N inserted into the outlet 1 and the grounding line E, By detecting the current flowing between the lines, it is determined whether or not it is normal.

Here, the ground line 5102 side of the secondary winding of the transformer 5100 is grounded by the first electrical terminal 5103 is Class B grounding specified in the technical standards for electrical equipment, and the load of the electric circuit On the side, the ground ground 5601 is grounded by the second electrical terminal 5203 through the ground wire 5202 is a D-type ground.

At this time, when the B type grounding and the D type grounding are performed, the concentrated grounding terminal 5601 is the grounding wire 5202, the second electrical terminal 5203, the ground 5001, the first electrical terminal. It is in a state where it is connected to the neutral line 5102 via 5103. That is, if the B type grounding resistance is R _B and the D type grounding resistance is R _D , the combined resistance between the grounding wire of the outlet and the neutral wire 5102 is
R _Total = R _B + R _D (Expression 3)

In this case, the power supply device 5301 is connected to the neutral wire 5102 on the load side of the electric circuit and the ground wire of the outlet through the connecting portion, and a voltage (voltage is set to E) is applied. The power supply device 5301 may use an AC power supply obtained from the electric circuit, or may use a DC power supply after rectification. Moreover, you may use the insulated power source which insulated the primary side and the secondary side as a power supply. Moreover, you may comprise using the capacitor | condenser which is an electrical storage member as DC power supply, for example.

Next, a current measurement unit 5302 measures a current (current is I) flowing between the neutral wire 5102 and the ground wire of the outlet. The current measuring means 5302 may be configured using a current transformer (CT) or a Hall element, or may be configured using other general current sensors. Here, when the B type grounding and the D type grounding are performed, the combined resistance between the grounding wire of the outlet and the neutral wire 5102 is R _Total = R as shown in (Equation 3). _Since it is expressed as _B + _RD , when voltage E is applied,
E / (R _B + R _D ) (Formula 4)
Is detected by the current measuring means 5302.

At this time, when the current I is detected, it is a case where the B-type grounding and the D-type grounding are performed, so that it is determined by the determination unit 5303a that the grounding system is connected. . When the current I is not detected, the ground wire of the outlet is connected to the neutral wire 5102 via the ground wire 5202, the second electrical terminal 5203, the ground 5001, and the first electrical terminal 5103. Since it is not connected, it is determined that the grounding system is not connected. Even if the wires are connected, if the grounding resistance is not appropriate and has increased from the reference value, the detected current will be very small. It may be configured to make a determination based on this threshold value.
The determination unit 5303a may be configured by using a microcomputer or an IC, and may perform the determination by setting a threshold value for the detection current represented by the relationship of (Equation 4), The determination may be made by configuring an electronic circuit using a diode, an operational amplifier or the like and detecting the magnitude of the detection current.

In this way, the connection state of the grounding system is determined by applying a voltage between the neutral wire in the electric circuit and the ground wire of the outlet through the connecting portion, and between the neutral wire and the ground wire of the outlet. Judgment means is provided in the outlet so that it can be confirmed by detecting the flowing current.

(Second example of determination means)
Next, a second example of determination means will be described.
The second example is a modification of the first example, in which a voltage is applied via a connecting portion between the voltage line 5101 side of the secondary winding of the transformer 5100 interposed in the electric circuit and the ground line of the outlet. It is configured to make a judgment by applying.

When the B-type grounding and the D-type grounding are performed, the grounding wire of the outlet is the grounding wire 5202, the second electrical terminal 5203, the ground 5001, the first electrical terminal 5103, the middle It is in a state of being connected to the voltage line 5101 side through the secondary wire of the conductive wire 5102 and the transformer. That is, if the class B ground resistance is R _B , the class D ground resistance is R _D , and the impedance of the secondary winding of the transformer is Z _L (= jωL: L is the inductance of the coil), The combined impedance with the line 5101 is
Z _Total = R _B + R _D + Z _L (Expression 5)

In this case, the power supply device 5301 is connected to the voltage line 5101 on the load side of the electric circuit and the ground line of the outlet, and a voltage (voltage is assumed to be E) is applied.

Next, a current flowing between the voltage line 5101 and the ground line of the outlet (current is I) is measured by a current measuring unit. Here, when the B type grounding and the D type grounding are performed, the combined resistance between the grounding wire of the outlet and the voltage wire 5101 is Z _Total = R _{B as shown in} (Equation 5). Since + R _D + Z _L , when voltage E is applied,
_{E / (R B + R D} + Z L) ··· ( Formula 6)
A current I expressed by the magnitude of is detected.

At this time, when the current I is detected, it is a case where the B-type grounding and the D-type grounding are performed, so that it is determined by the determination unit 5303a that the grounding system is connected. . When the current I is not detected, the grounding wire of the outlet is the grounding wire 5202, the second electrical terminal 5203, the ground 5001, the first electrical terminal 5103, the neutral wire 5102, the transformer. Therefore, it is determined that the grounding system is not connected because it is not connected to the voltage line 5101 side through the secondary winding. Even if the wires are connected, if the grounding resistance is not appropriate and has increased from the reference value, the detected current will be very small. It may be configured to make a determination based on this threshold value.

In this way, the connection state of the grounding system is determined by applying a voltage between the voltage line in the electric circuit and the grounding line of the outlet via the connection portion, and the current flowing between the voltage line and the grounding line of the outlet. Judgment means is provided in the outlet so that it can be confirmed by detecting. In general, the distribution board generally has multiple outlets on the load-side circuit of the branch switch. However, by applying a variable voltage, the current due to the original circuit voltage or the outlet The connection state of the grounding system can be confirmed by whether or not the current can be detected according to the voltage applied in a variable manner regardless of the load connected to the.

(Third example of judgment means)
Next, a third example of determination means will be described. FIG. 4 shows a third example.

In a third example, an electrical terminal 5203 provided on the ground 5001 is connected to a grounding wire of an outlet for grounding a device or the like via a grounding wire 5202 electrically connected to the electrical terminal 5203, By measuring the voltage between the neutral wire 5102 side of the secondary winding of the transformer 5100 interposed in the electric circuit and the ground wire of the outlet, Judgment and confirmation are made.

At this time, when the B type grounding and the D type grounding are performed, the grounding wire of the outlet is the grounding wire 5202, the second electric terminal 5203, the ground 5001, the first electric terminal. It is in a state where it is connected to the neutral line 5102 via 5103. That is, if the class B ground resistance is R _B and the class D ground resistance is R _D , the combined resistance between the ground line of the outlet and the neutral line 102 is
R _Total = R _B + R _D (Expression 3)

In this case, the voltage measuring means 5304 measures the voltage between the neutral wire 5102 on the load side of the electric circuit and the ground wire of the outlet. The voltage measuring means 5304 may be configured by an electronic circuit, or may be configured by using a microcomputer or IC having a voltage measuring function, other voltage sensors, or the like.

Here, when the B type grounding and the D type grounding are performed, the combined resistance between the grounding wire of the outlet and the neutral wire 102 is R _Total = R as shown in (Equation 3). _Since the voltage is expressed as _B + R _D , the voltage between the neutral wire 5102 and the grounding wire of the outlet simply corresponds to the voltage at the open end of the resistance circuit in which the combined resistor is interposed. A measured voltage value of approximately zero volts is detected with respect to the line-to-line voltage.

Further, when the B type grounding and the D type grounding are not performed, an open section exists in the middle of the resistance circuit in which the combined resistance is interposed, and the voltage is not stable. In other words, the measured voltage value is not approximately zero volts with respect to the line voltage between the neutral line and the voltage line.

When a measured voltage value of approximately zero volts is detected with respect to the line voltage between the neutral line and the voltage line, it is the case where the B type grounding and the D type grounding are performed. It is determined by 5303b that the grounding system is connected. Further, when the measured voltage value becomes a measured voltage value which is not substantially zero volts with respect to the line voltage between the neutral wire and the voltage wire, the ground wire of the outlet is the ground wire 5202, the second electric wire. Since it is not connected to the neutral wire 5102 via the target terminal 5203, the ground 5001, and the first electrical terminal 5103, it is determined that the grounding system is not connected.
The determination unit 5303b may be configured using a microcomputer or IC, and may perform the determination by setting a threshold value for the detection voltage, or may be configured as an electronic circuit using a resistor, a diode, an operational amplifier, or the like. The determination may be performed by detecting the magnitude of the detection voltage.

In this way, a judgment means is provided in the outlet so that the connection state of the grounding system can be confirmed by detecting the voltage value between the neutral wire in the electric circuit and the grounding wire of the outlet. ing.

(Fourth example of judging means)
Next, a fourth example of determination means will be described. FIG. 5 shows a fourth example.

In a fourth example, an electrical terminal 5203 provided on the ground 5001 is connected to a grounding wire of an outlet for grounding a device or the like via a grounding wire 5202 electrically connected to the electrical terminal 5203, Is determined by measuring a voltage between the voltage line 5101 side of the secondary winding of the transformer 5100 interposed in the electric circuit and the ground line of the outlet. It is to confirm.

At this time, when the B type grounding and the D type grounding are performed, the grounding wire of the outlet is the grounding wire 5202, the second electric terminal 5203, the ground 5001, the first electric terminal. 5103, Neutral wire 5102, The voltage wire 5101 side is connected via the secondary winding of the transformer. That is, if the class B ground resistance is R _B , the class D ground resistance is R _D , and the impedance of the secondary winding of the transformer is Z _L (= jωL: L is the inductance of the coil), The combined impedance with the line 5101 is
Z _Total = R _B + R _D + Z _L (Expression 5)

In this case, the voltage between the voltage line 5101 on the load side of the electric circuit and the ground line of the outlet is measured via the connection portion. The voltage measuring means 5304 may be configured by an electronic circuit, or may be configured by using a microcomputer or IC having a voltage measuring function, other voltage sensors, or the like.

Here, when the B type grounding and the D type grounding are performed, the combined impedance between the ground line of the outlet and the voltage line 5101 is Z _Total = R _{B as shown in} (Equation 5). + R _D + Z _L , the voltage between the voltage line 5101 and the ground line of the outlet simply corresponds to the voltage at the open end of the resistor-coil series circuit in which the combined impedance is interposed. A measured voltage value approximately equal to the line voltage between the sex line and the voltage line is detected.

When the B type grounding and the D type grounding are not performed, an open section exists in the middle of the resistance circuit in which the combined impedance is present, and the voltage is not stable. That is, a measured voltage value that is not substantially equal to the line voltage between the neutral line and the voltage line is measured.

If a measurement voltage value that is substantially equal to the line voltage between the neutral line and the voltage line is detected, the B-type grounding and the D-type grounding are performed, so the determination unit 5303c Thus, it is determined that the grounding system is connected. When the measured voltage value is not substantially equal to the line voltage between the neutral wire and the voltage wire, the ground wire of the outlet is the ground wire 5202, the second electrical wire. Since the terminal 5203, the ground 5001, the first electrical terminal 5103, the neutral line 5102, and the voltage line 5101 are not connected through the secondary winding of the transformer, the grounding system is connected. Judge that it is not.

The determination unit 5303c may be configured using a microcomputer or an IC, and may perform the determination by setting a threshold value for the detection voltage, or may be configured as an electronic circuit using a resistor, a diode, an operational amplifier, or the like. The determination may be performed by detecting the magnitude of the detection voltage.

In this way, the connection state of the grounding system is determined in the outlet so that the voltage between the voltage line in the electric circuit and the grounding line of the outlet can be measured and the grounding state can be confirmed from the measured voltage value. Is provided.

In the third and fourth examples, a voltage applying unit is provided in the judging means, and the voltage applied is varied by applying a voltage between the electric circuits to which the judging means is connected. It may be configured such that the connection state of the grounding system can be more clearly confirmed by determining whether or not voltage detection or current detection can be performed.

(Fifth example of judgment means)
Next, a fifth example of determination means will be described. FIG. 6 shows a fifth example.
The fifth example is provided with a connection part that is electrically connected to the voltage line, neutral line and grounding system of the circuit,
When the determination unit determines the connection state of the grounding system, the voltage line and the grounding system or the neutral line and the grounding system can be selectively connected among the electric circuit and the grounding system connected by the connecting unit. A connection state switching unit is provided to selectively perform the judgment shown in any one of the first to fourth examples described above or to merge the judgment shown in the first to fourth examples mentioned above. It is done by carrying out.

Reference numeral 5305 denotes a connection state switching unit, which may be configured by using a relay so as to selectively switch the connection between the voltage line and the neutral line, or selects the connection electronically inside the microcomputer or IC. You may comprise with a semiconductor switch.

When the voltage line is selected, the determination unit 5304d performs the determination of the above-described fourth example, and when the neutral line is selected, the determination unit 5304d has a function of determining the above-described third example. It is good to compose them. In addition, in the selected electric circuit, the first example or the second example described above may be determined.

Further, the determination unit 5304d may be configured to combine the determinations of the first to fourth examples described above on the electrical path selected by the connection state switching unit 5305 and to perform the determination in a composite manner.

As a result, the measurement data of various voltage values or current values necessary for making the determination by the determination unit 5303d are connected by the connection state switching unit 5305 to the connection between the voltage line and the ground system or the neutral line and the ground system. Can be obtained simply by selectively switching.

In the environment where the grounding system is provided, grounding in various surrounding environments is predicted as described above. Therefore, when checking the connection state of the grounding system, the connection state of the grounding system can be determined by one measurement method. Assuming the case where confirmation is performed and the case where various measurement methods are combined, the configuration of performing multiple measurements is provided in the outlet so that the connection status of the grounding system can be confirmed by one measurement method. Even if the test cannot be performed successfully, it is possible to check the connection status appropriately by using other measurement methods.

(Sixth example of judgment means)
Next, a sixth example of determination means will be described. FIG. 7 shows a sixth example.

The sixth example is provided with a switch means 5401 that is interposed between a ground terminal and a blade support in the outlet and separates / connects the ground wire 202 connected to the outlet, and is connected to the outlet by the switch means 5401. The grounded state A and the non-grounded state B are created by separating / connecting the connected grounding lines. In each of the grounded state A and the non-grounded state B, the first to fifth examples described above are used. Any one of the judgments shown is performed, and the measurement current value or the measurement voltage value obtained in both the ground state A and the non-ground state B is compared to confirm.

For example, based on the first example described above, a case where the switch means 5401 is interposed between the ground line of the outlet and the ground line 5202 will be described. The switch means 5401 may use a relay circuit or an electronic switch configured using an IC or a microcomputer.

In this case, first, in a state where the switch means 5401 is closed (ground state A), the power supply device 5301 is connected to the neutral wire 5102 on the load side of the electric circuit and the ground wire of the outlet, and the voltage (the voltage is assumed to be E). Apply. A current measuring means 5302 measures the current flowing between the neutral wire 5102 and the ground wire of the outlet (current is I). Here, when the B type grounding and the D type grounding are performed, the combined resistance between the grounding wire of the outlet and the neutral wire 5102 is R _Total = R as shown in (Equation 3). _Since it is expressed as _B + _RD , when voltage E is applied,
E / (R _B + R _D ) (Formula 4)
A current I expressed by the magnitude of is detected.

Subsequently, in a state where the switch means 5401 is opened (non-grounded state B), the power supply device 5301 is connected to the neutral wire 5102 on the load side of the electric circuit and the ground wire of the outlet, and the voltage (voltage is assumed to be E). Apply. Then, a current (meaning I) flowing between the neutral wire 5102 and the ground wire of the outlet is measured by current measuring means. At this time, since the ground line of the outlet and the neutral line 5102 are separated by the switch means 5401, the current I is not detected.

Here, when the judgment unit 5303e compares the current values obtained when the switch unit 5401 is closed (grounding state A) and opened (non-grounding state B), the type B grounding and the D When seed grounding is performed, the detected current value I changes between the ground state A and the non-ground state B, and when the class B grounding and the class D grounding are not performed. Is a state in which the grounding wire of the outlet is not connected to the neutral wire 5102 via the grounding wire 5202, the second electrical terminal 5203, the ground 5001, and the first electrical terminal 5103. The current value I does not change between the ground state A and the non-ground state B.

Therefore, the determination unit 5303e determines that the grounding system is connected when there is a change in the current value as a result of the comparison of the current values. If the current value is not changed as a result of the comparison of the current values, it is determined that the ground system is not connected.

Further, based on the third example described above, a description will be given of a case where the switch means 5401 is interposed between the grounding wire of the outlet and the grounding wire 5202.

In this case, first, the voltage between the neutral wire 5102 on the load side of the electric circuit and the ground wire of the outlet is measured with the switch means 5401 closed (ground state A).

Here, when the B type grounding and the D type grounding are performed, the combined resistance between the grounding wire of the outlet and the neutral wire 102 is R _Total = R as shown in (Equation 3). _Since it is expressed as _B + R _D , the voltage between the neutral wire 102 and the grounding wire of the outlet simply corresponds to the voltage at the open end of the resistance circuit in which the combined resistor is interposed, and the neutral wire and the voltage A measured voltage value of approximately zero volts is detected with respect to the line-to-line voltage.

Subsequently, the voltage between the neutral wire 5102 on the load side of the electric circuit and the ground wire of the outlet is measured with the switch means 401 opened (non-grounded state B).

In this case, since the ground line of the outlet and the voltage line 5101 are separated by the switch means 5401, the voltage is not stable. That is, the measured voltage value is not substantially equal to the line voltage between the neutral line and the voltage line.

Here, when the voltage values obtained when the switch means 5401 is closed (grounding state A) and opened (non-grounding state B) are compared, the B type grounding and the D type grounding are performed. The detected voltage value E changes between the grounding state A and the non-grounding state B, and when the B type grounding or the D type grounding is not performed, A ground line is connected to the voltage line 5101 side via the ground line 5202, the second electrical terminal 5203, the ground 5001, the first electrical terminal 5103, the neutral line 5102, and the secondary winding of the transformer. Therefore, the voltage value E does not change between the ground state A and the non-ground state B.

Therefore, the determination unit 5303e determines that the grounding system is connected when the voltage value is changed as a result of the comparison of the voltage values. Further, if the voltage value does not change as a result of the comparison of the voltage values, it is determined that the ground system is not connected.

Next, a description will be given of a case where the switch means 5401 is interposed between the ground line of the outlet and the ground line 5202 based on the fourth example described above.

In this case, first, the voltage between the voltage line 5101 on the load side of the electric circuit and the ground line of the outlet is measured with the switch means 5401 closed (ground state A).

Here, when the B type grounding and the D type grounding are performed, the combined resistance between the grounding wire of the outlet and the voltage wire 5101 is Z _Total = R _{B as shown in} (Equation 5). + R _D + Z _L , the voltage between the neutral wire 5102 and the ground wire of the outlet simply corresponds to the voltage at the open end of the resistor-coil series circuit in which the combined impedance is interposed, A measured voltage value approximately equal to the line voltage between the neutral line and the voltage line is detected.

Then, the voltage between the voltage line 5101 on the load side of the electric circuit and the ground line of the outlet is measured with the switch means 5401 open (non-grounded state B).

In this case, since the ground line of the outlet and the voltage line 5101 are separated by the switch means 5401, the voltage is not stable. That is, the measured voltage value is not substantially equal to the line voltage between the neutral line and the voltage line.

Here, when the voltage values obtained when the switch means 5401 is closed (grounding state A) and opened (non-grounding state B) are compared, the B type grounding and the D type grounding are performed. The detected voltage value E changes between the grounding state A and the non-grounding state B, and when the B type grounding or the D type grounding is not performed, A ground line is connected to the voltage line 5101 side via the ground line 5202, the second electrical terminal 5203, the ground 5001, the first electrical terminal 5103, the neutral line 5102, and the secondary winding of the transformer. Therefore, the voltage value E does not change between the ground state A and the non-ground state B.

Therefore, the determination unit 5303e determines that the grounding system is connected when the voltage value is changed as a result of the comparison of the voltage values. Further, if the voltage value does not change as a result of the comparison of the voltage values, it is determined that the ground system is not connected.

Similarly, in the case of the second example and the fifth example, by comparing the results obtained when the switch means 5401 is closed (grounded state A) and opened (non-grounded state B). Based on the change, the state of the grounding system is judged.

Note that the judgments shown in the first to fifth examples are combined and the measured current values or measured voltage values obtained in both the ground state A and the non-ground state B are compared. You may comprise so that it may confirm by.

Next, the discrimination state identification unit 100 provided in the outlet 1 with the ground electrode will be described. The determination state identification unit 100 displays the determination result by the above-described determination means so as to be visible from the outside of the outlet 1, and is particularly arranged so that identification can be performed from the side of the outlet 1 into which the plug is inserted. doing.

First, FIG. 8 is a block diagram of the determination unit 5303, the determination state identification unit 100, the switch 302, and the power source 303.

The switch 302 is a switch provided in the vicinity of the ground terminal and driven by receiving the displacement of the ground line when connecting / disconnecting the ground line to / from the ground terminal. Two contact systems are provided so that two states can be detected when the ground wire is inserted into the wire insertion hole and when it is not inserted. When the contact is closed and the ground wire is not connected, the second contact is energized in a certain direction and the second contact is closed. When the ground wire is inserted, the contact is received by the displacement of the rotating lever. It is good to comprise using the microswitch which opens and closes, and the microswitch which opens and closes a contact by being displaced when the ground wire is inserted.

As described above, the structure for detecting the displacement of the grounding wire may be a mechanical structure in which the grounding wire contacts the lever provided on the switch unit when the grounding wire is inserted, and the contact is opened / closed, or a magnet or the like. You may comprise using sensors, such as a proximity sensor using, and a photoelectric sensor which detects the change of illumination intensity.

A battery is used as the power source 303. Since the outlet is generally used for a long time, a secondary battery may be used in addition to the primary battery. Moreover, you may comprise using a capacitor | condenser and an electric double layer with a large electrostatic capacity for electrical storage. When using a power source that can be charged as described above, a charging circuit that performs charging by connecting to the voltage phase and neutral phase connected to the outlet is provided, and commercial power is supplied to the outlet after installation. In this case, the secondary battery may be charged. It should be noted that the battery 303 is shipped in a state where it is stored in advance, so that the discrimination state identification unit is appropriately displayed at the time of wiring work.

The determination state identification unit 100 includes a one-shot circuit 304 and a display unit 400. The one-shot circuit 304 receives the output from the determination unit 5303 and outputs a rectangular wave signal that is ON for a predetermined time. The one-shot circuit may be configured by using a flip-flop circuit, may be configured by a microcomputer having a one-shot function, or may be configured by using various circuits.

In the present embodiment, a self-holding display unit 400 of the judgment state identification unit 100 is used. The display unit 400 includes a permanent magnet and an electromagnet that is driven by receiving an output signal from the one-shot circuit 304 to form a self-holding display unit. The display unit is configured by pivotally supporting an identification unit provided with a permanent magnet between both ends of a yoke formed in a substantially U-shape. By changing the direction of the current flowing through the coil wound around the yoke, the polarity of the magnetic pole generated between both ends of the yoke is changed, and the repulsion / attraction operation is used between the magnetic poles of the permanent magnet and the yoke, The display state of the display unit is changed by rotating the identification unit from one state to another state. The discriminating unit is color-coded so that changes in the display state can be visually recognized.

When the electric wire 3 is inserted into the electric wire insertion hole, the power source 303 is applied to the one-shot circuit 304 and the display unit 400 displays that the electric wire has been inserted.

In order to acquire and store data about whether or not the grounding system is functioning over time, an electronic timer is provided in the determination unit 5303, or a determination unit is configured using a microcomputer to periodically It is configured so that the determination is performed.

In addition, it has a timer measurement function that counts at a predetermined time interval and counts the predetermined timing and date. For example, it is a change of season when the ground resistance is likely to change, or manually. The confirmation may be performed when confirmation is desired. Further, a sensor for measuring a change in weather, temperature, and humidity may be provided, and confirmation may be performed when the temperature or humidity has changed by a predetermined value from a reference value.

Also, when the ground line is pulled out, the switch 302 is driven and a signal is supplied to the one-shot circuit 304. At this time, the determination unit 5303 makes a determination. However, since the ground line is not connected and the grounding system is not functioning, the state of the determination unit facing the determination state confirmation window changes, so that the plug-in is inserted. It can be identified from the side where the plug is inserted that the ground wire is not connected to the ground terminal. It should be noted that the polarity of the output signal output from the one-shot circuit to the judgment state identification unit 400 may be changed depending on whether the ground wire is inserted or pulled out.

In FIG. 9, communication between the determination unit 5303 and the determination state identification unit 400 is performed by wireless communication, the switch 302 that is driven when the electric wire is inserted into the outlet 1, the power source 303 that supplies power to the circuit, and the power source after a certain time The example which provided the timer 305 which stops supply is shown.

The timer circuit 305 stops the power supply time to the one-shot circuit 304 and the wireless communication circuit 306 after a predetermined time from the start of power supply. The timer circuit may be a timer configured using a counter circuit, or a discharge circuit having a predetermined discharge time configured using a capacitor and a resistor.

As a result, when the ground wire 3 is inserted into the wire insertion hole provided in the outlet 1, the switch 302 is driven by the displacement of the ground wire, and the power source 303 is supplied to the determination unit 5303 and the one-shot circuit 304. . The determination unit 5303 performs a predetermined determination operation as described above, and outputs a signal to the one-shot circuit 304 based on the determination result. The one-shot circuit 304 and the wireless communication circuit 306 output an output signal for a predetermined time by the timer 305.

On the wireless communication circuit 402 side, the signal received from the wireless communication circuit 306 is processed by the arithmetic processing unit 4021 to display the display unit 400 and record data in the storage unit.

The display unit 400 that has received the output signal can identify whether the grounding system is normal from the side where the plug is inserted, based on the display state. Since power supply to the one-shot circuit 304 and the wireless communication circuit 306 is stopped after a certain time by the timer circuit 305, power consumption is suppressed as much as possible.

The determination state identification unit 100 configured in this manner is provided on the insertion surface of the plug in the outlet, but in addition to this, the determination state identification unit 100 is provided so as to be visible from the front direction of the mounting frame, the plate frame, and the decorative frame to which the outlet is attached. Can be configured.

Generally, the mounting frame, the plate frame, and the decorative frame to which the outlet is attached are configured separately from the outlet. Therefore, when the judgment state identification unit 100 is provided on the mounting frame, the plate frame, and the decorative frame, As shown in FIG. 10, a power storage unit 3031 is arranged on the construction material side around these frames, and power is supplied from the power storage unit 3031 to the determination state identification unit 100 via the connection unit 403. 1 and 2 in FIGS. 1 and 2 so that the discrimination state identification unit 100 can be viewed from the side where the plug of the outlet 1 is inserted. As shown in FIG. Further, a light transmissive portion may be provided instead of the hole portion. Further, the power storage unit 3031 may be arranged only in a part of the periphery in accordance with the power supply capacity.

1 and 2 are not limited to the illustrated positions, and may be variously arranged, for example, from the left, right, up, down, and from the front to the side of the frame.

An installation frame for embedding and attaching an outlet to an embedding hole provided in the construction material 40, or a plate frame that is fixed to the mounting frame so as to surround the embedding hole. By providing the decorative frame 30 that is attached to the side into which the plug is inserted with respect to the construction material 40, a degree of freedom can be obtained in a place where the display unit is attached, and the display unit 400 can be visually viewed. Can be provided.

In addition, regarding signal communication between the one-shot circuit and the 304 display unit 400, the outlet case and the mounting frame, the mounting frame and the plate frame, and the mounting portion and the fitting portion of the plate frame and the decorative frame are as follows. It is good to do. Since the plate frame and the decorative frame are made of resin, a wiring pattern may be formed inside the resin, and a contact portion may be provided at an attachment portion or a fitting portion between the plate frame and the decorative frame to form an electric circuit. Since the mounting frame is generally made of metal, it is preferable to ensure insulation by providing a coating on the wiring on the mounting frame.

In addition to the wired signal communication, a wireless signal transmission / reception unit may be provided in the one-shot circuit 304 and the display unit 400 to perform signal communication by wireless communication. Since the wireless signal only needs to be transmitted in the immediate vicinity of the outlet, the output may be small, so that power consumption can be suppressed. In addition, as a wireless system, a wireless system with low power consumption may be selected as appropriate.

In addition, the charging of the power storage unit may be either a contact type or a non-contact type.

In the case of the contact type, the charging circuit and the voltage electrode and the neutral electrode inside the housing of the outlet are physically connected, and power is supplied from the charging circuit to the power storage unit. The wiring connection from the voltage electrode and the neutral electrode to the charging circuit, or from the voltage electrode and the neutral electrode to the power storage unit, as in the signal communication between the one-shot circuit 304 and the display unit 400, It is good to carry out via the attachment part and fitting part of a frame and a plate frame, and a plate frame and a decorative frame. Since the plate frame and the decorative frame are made of resin, a wiring pattern may be formed inside the resin, and a contact portion may be provided at an attachment portion or a fitting portion between the plate frame and the decorative frame to form an electric circuit. Since the mounting frame is generally made of metal, it is preferable to ensure insulation by providing a coating on the wiring on the mounting frame.

In the case of the non-contact type, the coil is arranged concentrically inside the casing of the outlet and the frame so that electric power can be transmitted using electromagnetic induction. In addition, the power may be transmitted by radio wave reception, magnetic resonance, or the like.

As a result, when the commercial power is supplied after installing the outlet wiring, charging of the power storage unit is started by the charging circuit, and the necessary power source is continuously secured for the one-shot circuit 304 and the determination means. be able to.

As another example of the display unit 400, display using LEDs or liquid crystal may be performed in addition to the self-holding type.

For example, as shown in FIG. 11, in the determination state identification unit 100, instead of the one-shot circuit 304, a display data generation unit 3041 that generates display data based on the determination result by the determination unit described above, and the display And a display unit for displaying the display data generated by the data generation unit.

The display data generation unit 3041 generates display data to be displayed on the display unit 400 based on the determination result output from the determination unit. Specifically, it may be constituted by a microcomputer or a driver having a character generator function. The display data generates data that can grasp the status of the grounding system, such as the state of the grounding system connection, the measured current value, the measured voltage value, and the grounding resistance value obtained as a result of the judgment unit calculation. It is good to make it output toward 400.

12 and 13 show an example in which the display unit 400 is configured using a liquid crystal display. The liquid crystal display appropriately displays the character display data described above. The display unit 400 may be configured more simply using an organic EL display having a display function visible from the outside, an LED, or the like. FIG. 12 shows an example in which the decorative panel is provided with a liquid crystal display, and FIG. 13 shows an example in which the outlet main body is provided with a liquid crystal display. Here, “0V” displayed as an example indicates the display based on the third embodiment, and the neutral wire 5102 side of the secondary winding of the transformer 5100 and the grounding wire of the outlet. The voltage between and is displayed. For general consumers, the measured value itself may not be necessary, so usually only “Good” is displayed simply, and this value is displayed as needed when the security contractor confirms. Alternatively, a display changeover switch may be provided separately.

In addition, as an example of a simpler case, in FIG. 14, a display distinguished by the display color of the LED 401 is performed, and when it is determined that the ground connection state is good, the green LED is lit, and the ground connection state In the example, the red LED is turned on when it is determined that the light is not good.

Next, as a display means for displaying the state of the grounding system, a description will be given of a configuration that includes a display unit 400 and a device that mechanically displays whether or not the grounding wire is connected to the outlet 1.

In this configuration, the display unit 400 electrically displays whether the function of the grounding system is normal or not, but if the state of the grounding system is not normal, the failure point is identified and the cause of the cause A display unit 400 that can mechanically determine whether or not the ground wire is connected to the outlet 1 is provided on the side where the plug is inserted so that the disconnection can be performed more quickly.

15 to 18 show the case where the ground wire is driven by using the insertion force when inserted into the electric wire insertion hole of the outlet 1 and the ground wire is connected or not. As long as the visual recognition state from the terminal changes and the ground wire is connected to the ground terminal, an example of the display unit that can always visually recognize the discrimination state identification unit 401a from the outside is shown.

First, the display unit shown in FIGS. 15 and 16 is rotated by receiving the insertion force of the ground wire so that the discrimination state identification unit 401a can be visually recognized from the outside. The display part is provided inside the outlet 1 so as to be rotatable, and is provided at one end with an abutting part 402a that is exposed to the insertion path 104 of the electric wire and abuts against the conductor part of the electric wire to obtain rotational force. At the end, a display unit configured to include a discrimination state identification unit 401a that rotates when the electric wire comes into contact with the contact portion 402a and is visible from the discrimination state confirmation window 401 is shown.

The abutting portion 402a is inclined with respect to the insertion direction so as not to disturb the movement of the electric wire insertion when the electric wire abuts, and to obtain a component force in the rotational direction by receiving a force in the insertion direction. The surface which was made to provide is provided.

As a result, when the ground wire 3 is inserted into the electric wire insertion hole 103, the conductor portion of the electric wire passes through the insertion passage 104 and comes into contact with the contact portion 402a, and the display portion 400a rotates clockwise in FIG. It can be seen that 401a is visibly displaced from the discrimination state confirmation window 400, and that the ground wire is connected to the ground terminal from the side into which the plug of the outlet 1 is inserted. When the grounding wire 3 is pulled out, the display unit 400a rotates counterclockwise in the drawing, and the discrimination state identification unit 401a is displaced from the discrimination state confirmation window 400 so that it cannot be visually recognized. From the side where you insert

Next, the display part 400b of FIGS. 17 and 18 receives the insertion force of the ground wire and is pressed in the insertion direction, so that the discrimination state identification part 401b can be visually recognized from the outside. The display portion 400b is formed in the shape of an elongated rod, and the ground wire and the shaft are substantially the same in the wire insertion passage 104, the hollow portion 404b communicating with the insertion passage 104, and the guide portion 405b communicating with the hollow portion. Be placed.

The display unit 400b is provided with an abutting portion 402b that abuts against the conductor of the grounding wire at one end, and a discrimination state identifying unit 401b in a direction opposite to the insertion direction of the grounding wire at a substantially central portion. And a stopper 406b that receives the force of the elastic body and abuts against the inner wall of the hollow portion to regulate the position of the display portion 400b. Further, the periphery of the discrimination state identification unit 401b is formed of an elastic member so as to have flexibility along the guide unit 405b.

As a result, when the ground wire 3 is inserted into the electric wire insertion hole 103, the conductor portion of the electric wire comes into contact with the contact portion 402b facing the insertion passage 104 and resists the force of the elastic body. The determination state identification unit 401b is visibly displaced from the determination state confirmation window 400, and it can be seen from the outside of the outlet 1 that the ground wire is connected to the ground terminal. When the ground wire 3 is pulled out, the display unit 400b is displaced in the direction of the wire insertion hole entrance by the pressing force of the elastic body, and the discrimination state identification unit 401b is not visible from the discrimination state confirmation window 100. It can be seen from the side where the plug of the outlet 1 is inserted that it is displaced and pulled out.

Since the display unit 401 for displaying whether or not the grounding wire is connected is provided on the side where the plug of the outlet 1 is inserted, it is electrically determined whether or not the function of the grounding system is normal. When the status of the grounding system is not normal in combination with the display unit 400 that performs display, first, the failure point and the cause identification such as whether or not the grounding wire is connected to the outlet itself are performed more quickly. Will be able to.

As described above, after the grounding work and electrical wiring work have been done, whether or not the grounding system is functioning normally is normal at the position of the outlet that supplies power to the electrical equipment and from the side where the plug is inserted. It is possible to check whether it is functioning on a daily basis, without being bothersome, without the need for a commercial power supply even during construction, etc., at a position where it can be easily seen from the side where the plug is inserted into the outlet. If a malfunction is anticipated, it is possible to provide an outlet with a grounding electrode that can quickly identify the failure point and isolate the cause.

The present invention may be widely applicable to outlets and multi-tap with a grounding electrode that are generally used for residential and industrial purposes.

DESCRIPTION OF SYMBOLS 1 Outlet 2 Insert plug 3 Grounding wire 20 Plate frame 30 Cosmetic frame 40 Construction material 31 Judgment state confirmation window 100 Judgment state confirmation window 101 Grounding terminal 102 Grounding terminal 103 Electric wire insertion hole 104 Insertion path 200 Grounding wire connection state judgment means 201 Judgment State identification unit 202 Abutting part 203 Elastic body 204 Cavity part 205 Guide part 206 Stopper 300 Ground wire connection state determination means 302 Switch 303 Power supply 304 One-shot circuit 305 Timer 306 Radio signal transmission part 400 Display part 401 Determination state identification part 402 Wireless Communication unit 4021 connection unit

Claims (10)

The neutral side of the secondary winding of the transformer interposed in the electric circuit is grounded by the first electrical terminal provided on the ground,
A grounding system in the load side electric circuit of the transformer is connected to an electric circuit grounded by a second electric terminal provided on the ground through a centralized grounding terminal, and is provided to supply power to an electric device. An outlet with a grounding electrode,
On the back side, which is the inner side of the construction material of the outlet, is equipped with a grounding terminal to which the grounding wire of the circuit is connected
Inside the housing of the outlet,
As a means of determining the grounding state,
A voltage application unit for applying a voltage between a voltage line or a neutral line in the electric circuit and a ground system in the load side electric circuit of the transformer;
A current detection unit for detecting a current flowing between the electric circuit and the ground system by a voltage applied by the voltage application unit;
When the current is detected by the current detector, it is determined that the grounding system is connected,
When the current is not detected, a determination unit for determining that the grounding system is not connected is provided,
On the surface side into which the blade of the plug of the outlet is inserted, at least an earth terminal that is electrically connected to the ground terminal and is connected to the ground wire of the electrical equipment;
A judgment state identification unit that is connected to the judgment unit and is arranged so that the judgment state is visible from the side into which the plug of the outlet is inserted;
An outlet with a grounding electrode, characterized in that the judgment status can be identified from the side where the plug is inserted. Instead of the judging means described in claim 1,
In the load side circuit of the transformer,
A voltage measuring unit for measuring a voltage between a neutral wire and a grounding system in the electric circuit;
When the voltage is measured by the voltage measuring unit and the voltage measured with respect to the line voltage between the neutral wire and the ground wire of the secondary winding of the transformer is approximately zero volts, the ground Judging that the system is connected,
2. A grounding electrode as set forth in claim 1, further comprising: a judgment unit configured to judge that the grounding system is not connected when a voltage value obtained by measuring the voltage is not substantially zero volts. Outlet. Instead of the judging means described in claim 1 ,
In the load side circuit of the transformer,
A voltage measuring unit for measuring a voltage between a voltage line and a grounding system in the electric circuit;
When the voltage is measured by the voltage measuring unit and the voltage value measured with respect to the line voltage between the neutral line and the voltage line of the secondary winding of the transformer is a substantially equal voltage value, Judging that the grounding system is connected,
2. A determination unit comprising a determination unit configured to determine that the ground system is not connected when the voltage values obtained by measuring the voltages are not substantially equal to each other. Outlet with grounding electrode. The determination means includes
A connection state switching unit for selectively switching the connection with the voltage line or the neutral line to which the determination means is connected;
4. The outlet with a grounding electrode according to claim 1, further comprising a determination unit for selectively or merging the determination by the determination unit according to claim 2 or 3. The determination means includes
A switch means interposed between the ground terminal and the ground terminal, and for switching on and off the electrical connection between the ground terminal and the ground terminal;
The judging means is provided with a judging section for selectively or merging judgment by the judging section according to claim 2 or 3 in each of the on state and the off state. Outlet with grounding pole as described. The judgment state identification part is provided on a mounting frame for fixing the outlet to the construction material,
6. The outlet with a grounding electrode according to claim 1, wherein the judgment state can be identified from the side into which the plug is inserted. The determination state identification unit is provided on a plate frame fixed to the mounting frame so as to surround a buried hole provided when the outlet is fixed to the construction material,
6. The outlet with a grounding electrode according to claim 1, wherein the judgment state can be identified from the side into which the plug is inserted. The determination state identification unit is provided on a decorative panel attached to the plate frame on the side opposite to the construction material with respect to the plate frame,
6. The outlet with a grounding electrode according to claim 1, wherein the judgment state can be identified from the side into which the plug is inserted. When the surface into which the plug of the outlet plug is inserted is the front surface and the surface to which the grounding wire is connected is the back surface, the mounting frame, the plate frame, and the decorative panel have a hole in the front portion of the judgment state identification portion. Part or translucent part,
The outlet with grounding electrode according to any one of claims 6 to 8, wherein the judgment state identification unit is configured to be visible from the outside on the side where the insertion plug is inserted. The determination unit and the determination state identification unit are provided with wireless communication units, respectively, and communication between the determination unit and the determination state identification unit is performed wirelessly, and the determination state identification unit is connected to the insertion plug. The outlet with a grounding electrode according to any one of claims 6 to 9, wherein the outlet is configured to be visible from the outside.

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