Three-phase, three-wire electric shock prevention terminal block having leakage current recovery function

Abstract

According to one aspect of the present invention, provided is a three-phase, three-wire electric shock prevention terminal block which is connected to the secondary side of a three-phase, three-wire transformer without a neutral line and intermediately connects a wire to supply power to a load, the terminal block comprising: a terminal block body; a plurality of connection terminals which is provided in the terminal block body and to which cables, including a three-phase, three-wire cable and electrical component cables for supplying power to electrical components, are respectively connected; a leakage current-guiding member provided in the terminal block body and configured to guide a leakage current generated in the terminal block; and a circuit module provided in the terminal block body and configured to recover the leakage current guided by the leakage current-guiding member.

Description

3-phase, 3-wire, electric shock prevention terminal block with leakage current recovery function

[0001] The present invention relates to an electric shock prevention terminal block, and more particularly, to a three-phase, three-wire electric shock prevention terminal block having a leakage current recovery function that prevents electric shock accidents by recovering leakage current flowing through the terminal block to the power supply side in a case where there is no neutral wire on the secondary side of a three-phase, three-wire transformer, and that allows the terminal block to operate normally even when submerged.

[0002]

[0003] Electric shock is a phenomenon in which the human body reacts when the leakage current flowing from the power source through the human body to the ground exceeds a certain level.

[0004] Typically, a leakage current of 15 mA or more causes convulsions, and a current of 50 mA or more can lead to death. The most common cause of death is cardiac arrest, which occurs when the heart stops functioning due to the current flowing through the heart damaging nerves.

[0005] The risk of electric shock is related to the body's resistance when the current is applied, which is largely dependent on the condition of the skin.

[0006] Meanwhile, a power terminal block is an electrical component that connects wires to supply power to a load through a circuit breaker in a current transformer, low-voltage distribution board, or motor control panel.

[0007] The terminal block is composed of a terminal block body having a terminal groove where a plurality of terminals are connected, a protective cover that covers the upper part of the terminal block body, and a fastening member that allows the terminal block body and the protective cover to be detachably connected to each other.

[0008] When electrical equipment including these terminal blocks is submerged in water and a human body comes into contact with the water or the conductive parts that are energized through the water, current flows from the exposed conductors of the equipment through the water and the human body to the ground, which is the ground plane.

[0009] At this time, the human body becomes very dangerous because its skin is easily wet with water and in that case, the contact resistance is extremely low.

[0010] A short circuit between power lines is a problem that occurs when the insulation between the two lines decreases, increasing electrical conductivity, causing a sudden flow of current, which can cause fire or short circuit damage to electrical equipment.

[0011] In general, the insulating properties of air are very high, so electrical insulation is maintained between two wires through air.

[0012] However, if a highly conductive fluid fills the space between the two lines due to flooding or other reasons, the current between the phases increases rapidly, causing a short circuit.

[0013] As a related technology, a prior art having a leakage current limiting device is described with reference to Fig. 1. Fig. 1 is a schematic diagram of a three-phase, four-wire interphase current and leakage current limiting device of an electrical facility according to the prior art.

[0014] As illustrated in FIG. 1, Korean Patent Publication No. 10-2023-0061805 discloses a three-phase, four-wire interphase current and leakage current limiting device for a submerged electrical facility, which is connected to a distribution line of the electrical facility and prevents electric shock in the event of submergence of the electrical facility or other electrical facilities located nearby by being electrically connected to the electrical facility, wherein one end is provided with a three-phase line terminal (12a, 12b, 12c) electrically connected to the three-phase lines (2a, 2b, 2c) of the distribution line, and the other end is provided with a phase line portion (22a, 22b, 22c) that is not surrounded by an insulator and is electrically connected to the electrical facility (200). One end is provided with a neutral line terminal (14a, 14b, 14c) electrically connected to the neutral line (4) of the distribution line, and the other end is provided with an internal neutral line (34a, 34b, 34c) electrically connected to an electrical facility (200) and a tubular line (26a, 26b, 26c) made of a conductive material that surrounds the phase line section (22a, 22b, 22c); One end is provided with a grounding line terminal (16a, 16b, 16c) electrically connected to a grounding line (6) of a distribution line, and the other end is electrically connected to an electrical facility (200), and is formed of an insulator and has a housing ground (28a, 28b, 28c) with a ground wire provided on the inner surface of the housing that surrounds the cylindrical line (26a, 26b, 26c) and an internal grounding line (36a, 36b, 36c) electrically connected to each other; A three-phase, four-wire interphase current and leakage current limiting device for a submerged electrical facility is disclosed, which can limit a sudden current increase of the electrical facility to prevent electric shock, and which includes an insulating tube (24a, 24b, 24c) which is respectively placed between the internal phase lines (32a, 32b, 32c) and the tubular lines (26a, 26b, 26c) and surrounds the internal phase lines (32a, 32b, 32c).

[0015] In this technology, the leakage current is limited by allowing the current flowing through the cylindrical line (26a, 26b, 26c) to flow to the ground via the internal ground line (36a, 36b, 36c) through the housing ground (28a, 28b, 28c) by combining the limited phase current and the current flowing from the electric load to the internal neutral line (34a, 34b, 34c).

[0016] However, since the housing ground is grounded to the ground of the third type, there is a resistance of approximately 100 ohms between the ground and the housing ground. Therefore, if a pedestrian touches a streetlight pole that has been grounded to the housing during flooding, there is a risk of electric shock.

[0017] Meanwhile, in the past, when there was no neutral wire on the secondary side of the transformer, only the third-class grounding work was performed on the load electrical equipment. Therefore, even if leakage current flows in the electrical equipment when touching the electrical equipment in normal times, the leakage current flows to the ground, so there is no risk of electric shock. However, when touching the electrical equipment during flooding, there is a problem that the leakage current that should flow to the ground flows to the human body, exposing one to the risk of electric shock.

[0018]

[0019] Accordingly, the purpose of the present invention to solve the above-mentioned conventional problems is to provide a three-phase, three-wire electric shock prevention terminal block having a leakage current recovery function that can recover leakage current flowing to a terminal block by providing a leakage current recovery unit between the secondary side of a transformer and a terminal block when there is no neutral wire of a three-phase, three-wire type on the secondary side of a transformer, and that allows the terminal block to operate normally even when submerged.

[0020] The problems solved by the present invention are not limited to those mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the description below.

[0021]

[0022] According to one aspect of the present invention for achieving the above objects and other features of the present invention, a terminal block for preventing electric shock is provided, which is connected to the secondary side of a three-phase, three-wire transformer without a neutral wire and connects an intermediate wire to supply electric power to a load, comprising: a terminal block body; a plurality of connection terminals provided in the terminal block body, each of which is connected to a cable including a three-phase, three-wire cable and an electric component cable for supplying electric power to an electric component; a leakage current induction member provided in the terminal block body and configured to induce a leakage current generated in the terminal block; and a circuit module provided in the terminal block body and configured to recover a leakage current induced by the leakage current induction member.

[0023]

[0024] According to the three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention, a leakage current recovery unit is arranged between the secondary side of a transformer and the electric equipment, so that the leakage current flowing in the electric equipment can be recovered to the power side of the secondary side of the transformer, and in the event that the terminal block not connected to the neutral line of the three-phase, three-wire system is submerged, even if a person touches the terminal block, the leakage current does not flow to the human body, so that not only does an electric shock accident not occur, but also the electric equipment can operate normally even during submersion.

[0025] The effects of the present invention are not limited to those mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the description below.

[0026]

[0027] Figure 1 is a schematic diagram of a three-phase, four-wire interphase current and leakage current limiting device of an electrical facility according to the prior art.

[0028] Figure 2 is a perspective view showing a three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention.

[0029] Figure 3 is an exploded perspective view showing a three-phase, three-wire electric shock prevention terminal block having a leakage current recovery function according to the present invention.

[0030] Figure 4 is a perspective view of a terminal block body included in a three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention, viewed from the upper side.

[0031] FIG. 5 is a perspective view of a terminal block body included in a three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention, viewed from the lower side.

[0032] Fig. 6 is a perspective view showing a leakage current induction member included in a three-phase, three-wire electric shock prevention terminal block having a leakage current recovery function according to the present invention.

[0033] FIG. 7 is a circuit diagram of a three-phase, three-line leakage current recovery circuit according to one embodiment of a leakage current recovery unit of a circuit module included in a three-phase, three-line electric shock prevention terminal block having a leakage current recovery function according to the present invention.

[0034] FIG. 8 is a circuit diagram of a three-phase, three-line leakage current recovery circuit according to another embodiment of the present invention, which is a leakage current recovery unit of a circuit module included in a three-phase, three-line electric shock prevention terminal block having a leakage current recovery function.

[0035]

[0036] Additional objects, features and advantages of the present invention can be more clearly understood from the following detailed description and accompanying drawings.

[0037] Before going into a detailed description of the present invention, it should be understood that the present invention can be modified in various ways and can have various embodiments, and that the examples described below and illustrated in the drawings are not intended to limit the present invention to specific embodiments, but include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

[0038] In addition, when describing with reference to the attached drawings, identical components will be assigned the same reference numerals regardless of the drawing numbers, and redundant descriptions thereof will be omitted. When describing the present invention, if a detailed description of a related known technology is judged to unnecessarily obscure the gist of the present invention, such detailed description will be omitted.

[0039] Hereinafter, a three-phase, three-wire electric shock prevention terminal block having a leakage current recovery function according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 2 to 8.

[0040] In the description below, electrical products or loads refer to electrical appliances or electrical devices that utilize three-phase power, and may be, for example, a three-phase motor.

[0041] FIG. 2 is a perspective view showing a three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention, FIG. 3 is an exploded perspective view showing a three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention in an exploded form, FIG. 4 is a perspective view of a terminal block body included in a three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention as viewed from the upper side, and FIG. 5 is a perspective view of a terminal block body included in a three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention as viewed from the lower side. FIG. 6 is a perspective view showing a leakage current induction member included in a three-phase, three-line electric shock prevention terminal block having a leakage current recovery function according to the present invention, FIG. 7 is a three-phase, three-line leakage current recovery circuit diagram of one embodiment of a leakage current recovery unit of a circuit module included in a three-phase, three-line electric shock prevention terminal block having a leakage current recovery function according to the present invention, and FIG. 8 is a three-phase, three-line leakage current recovery circuit diagram of another embodiment of a leakage current recovery unit of a circuit module included in a three-phase, three-line electric shock prevention terminal block having a leakage current recovery function according to the present invention.

[0042] The three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention is an electrical component that connects wires in the middle to supply power to an electrical product (load), and as shown in FIGS. 2 to 8, largely includes a terminal block body (100), a connection terminal (200), a leakage current induction member (300), and a circuit module (400).

[0043] Specifically, a three-phase, three-wire electric shock prevention terminal block having a leakage current recovery function according to the present invention comprises, as shown in FIGS. 2 to 8, a terminal block, which is an electrical component that connects wires in the middle to supply power to an electrical product (load), comprises: a terminal block body (100) formed in an enclosure shape; a plurality of connection terminals (200) provided in the terminal block body (100) and to which a three-phase, three-wire cable (wire) (11) and an electrical component cable (12) for supplying power to an electrical component are respectively connected; a leakage current induction member (300) provided in the terminal block body (100) and configured to induce a leakage current generated in the terminal block; and a circuit module (400) mounted in the terminal block body (100), having a circuit line electrically connected to the connection terminal (200), and configured to recover a leakage current induced by the leakage current induction member (300).

[0044] The terminal block body (100) above can be formed into a housing having a shape in which the plurality of connection terminals (200) are provided to be connected to cables (11, 12) and in which a leakage current induction member (300) and a circuit module (400) can be mounted.

[0045] Specifically, the terminal body (100) includes a body portion (110) and a cover portion (120) that covers the upper and lower portions of the body portion (110). The cover portion (120) may be optionally provided.

[0046] The above body part (110) may include a body base part (111), a cable connection hole part (112), a terminal mounting part (113), and a body fastening part (114).

[0047] The above body base portion (111) is injection-molded with an insulating material, and a cable connection hole portion (112) and a terminal mounting portion (113) can be formed.

[0048] The above cable connection hole (112) is formed on one side of the body base (111) and can induce the insertion of each cable (11, 12). For example, the cable connection hole (112) can be arranged in the left and right directions on the front of the body base (111). The cable connection hole (112) can be arranged to face each connection terminal (200).

[0049] The terminal mounting portion (113) is formed on the upper portion of the body base portion (111), communicates with the cable connection hole portion (112), and can be formed to induce insertion of the connection terminal (200).

[0050] For example, the terminal mounting portion (113) may include a first terminal body mounting portion (113a) that is sunken into the upper surface of the body base portion (111) and communicates with the cable connection hole portion (112), and a second terminal body mounting portion (113b) that is sunken into the upper surface of the body base portion (111) and is connected to the first terminal mounting portion (131) and restricts rotation of the connection terminal (200).

[0051] The above body fastening portion (114) is insert-molded into the body base portion (111) and is exposed at the upper and lower portions of the body base portion (111) so as to be electrically connected to the leakage current induction member (300). For example, the body fastening portion (114) is made of a conductor and can be insert-molded into the body base portion (111) so as to be positioned at four corners of the body base portion (111).

[0052] Here, the body fastening portion (114) is configured not to be electrically connected to the leakage current induction member (300), and at this time, the leakage current induction member (300) can be directly connected to the circuit module (400) through a separate wire (cable) or circuit line. In other words, the body fastening portion (114) can be configured to fasten the cover portion (120) while covering the leakage current induction member (300) to the body base portion (111). At this time, if the cover portion (120) is omitted, the body fastening portion (114) can be omitted.

[0053] The above body portion (110) may further include a body mounting portion (115). The body mounting portion (115) may be formed on the body base portion (111) and may provide a mounting space for the leakage current induction member (300) so that the cable (11, 12) passes through the leakage current induction member (300) before being connected to the connection terminal (200). For example, the body mounting portion (115) may include a first body mounting groove portion (115a) formed on the bottom surface of the body base portion (111), and a second body mounting groove portion (115b) communicated with the first body mounting groove portion (151a) and the cable connection hole portion (112). The second body mounting groove portion (115b) may be formed only on the movement path of the cable (11, 12) passing through the connection terminal (200).

[0054] Continuing, the cover part (120) is coupled to the body part (110) and configured to cover the leakage current induction member (300). For example, the cover part (120) may include a lower cover part (121) that is assembled to the lower part of the body base part (111) and covers the leakage current induction member (310) on the lower side, and an upper cover part (122) that is assembled to the upper part of the body base part (111) and covers the leakage current induction member (320) on the upper side.

[0055] Next, the above-mentioned connection terminal (200) is a component to which a three-phase, three-wire cable (wire) (11) provided in the terminal block body (100) and an electric component cable (12) for supplying power to an electric component are respectively connected.

[0056] Specifically, the above-mentioned connection terminal (200) may include a terminal connection portion (210), a terminal fixing portion (220), and a terminal restraint portion (230).

[0057] The terminal connection portion (210) is insert-molded into the body base portion (111), is connected to the cable portion (100) passing through the cable connection hole portion (112), and can be connected to the substrate portion (30). For example, the terminal connection portion (210) may include a first terminal connection portion (211) having holes formed on the front and upper surfaces and formed integrally with the body base portion (111), and a second terminal connection portion (212) protruding from the first terminal connection portion (211) and connected to the circuit board (410) of the circuit module (400).

[0058] The terminal fixing portion (220) may be configured to be fastened to the terminal connection portion (210) to fix the cable (11, 12). For example, the terminal fixing portion (220) may be screw-coupled through a hole formed on the upper surface of the first terminal connection portion (211) to pressurize the cable portion (100) connected to the terminal connection portion (210).

[0059] The above terminal restraint part (230) is inserted into the terminal mounting part (113) to cover the terminal fixing part (220) and is configured to restrain the terminal fixing part (220).

[0060] For example, the terminal restraint portion (230) may include an insulating material to protect the terminal fixing portion (220) and the terminal connection portion (210).

[0061] The terminal restraint portion (230) may include a first restraint portion (231) inserted into the first body insertion portion (131) and covering the terminal fixing portion (220), and a second restraint portion (232) extending laterally from the first restraint portion (231) and inserted into the second terminal body mounting portion (113b) to limit rotation. The terminal restraint portion (230) may limit rotation and thus may limit loosening of the screw of the terminal fixing portion (220).

[0062] Next, the leakage current induction member (300) is a component provided within the terminal block body (100) and configured to induce leakage current generated in the terminal block.

[0063] The above leakage current inducing member (300) is arranged to surround the connection terminal (200), is made of a conductor, and induces leakage current generated at the connection terminal (200) so that it is recovered in the leakage current recovery section of the circuit module.

[0064] For example, a leakage current induction member (300) may be arranged in front of and above a connection terminal (200) to induce leakage current generated in the terminal block when submerged, for example, leakage current generated in the connection terminal (200). The leakage current induction member (300) may be made of a metal material having excellent conductivity, such as copper, copper alloy, aluminum, or aluminum alloy.

[0065] Specifically, the leakage current induction member (300) may include a lower leakage current induction member (310) and an upper leakage current induction member (320).

[0066] The lower side leakage current induction member (310) is mounted on the lower part of the body base part (111) and is configured to allow a cable (11, 12) to pass therethrough. For example, the lower side leakage current induction member (310) is made of a conductor, is electrically connected to the body fastening part (114), and can collect leakage current leaking forward of the connection terminal (200).

[0067] Specifically, the lower side leakage current induction member (310) may include a base plate portion (311), a connecting portion (312), and a protruding plate portion (313).

[0068] The above base plate portion (311) is placed on the lower surface of the body base portion (111) and can be combined with the body fastening portion (114). For example, the base plate portion (311) can be inserted into the first body mounting groove portion (115a) and maintained in an electrically connected state with the body fastening portion (114) while being screw-connected to the body fastening portion (114).

[0069] The above connecting portion (312) protrudes from the base plate portion (311) and can be electrically connected to the circuit module (400). For example, the connecting portion (312) can be maintained in an electrically connected state with the circuit module (400) through a screw connection or a cable (wire).

[0070] The above protruding plate portion (313) protrudes upward from the base plate portion (311) and may be formed with a hole portion (313a) through which a cable (11, 12) passes. For example, the protruding plate portion (313) is inserted into the second body mounting groove portion (115b), and the hole portion (313a) is arranged in a straight line with each of the body mounting groove portions (115b) to allow the cable (11, 12) to pass through.

[0071] Continuing, the upper leakage current inducing member (320) may be mounted on the upper portion of the body base portion (111) and configured to cover the connection terminal (200) and the substrate portion (410) of the circuit module (400). For example, the upper leakage current inducing member (320) is made of a conductor, is electrically connected to the body fastening portion (114), and is configured to collect leakage current leaking upward from the connection terminal (200).

[0072] Specifically, the upper leakage current induction member (320) may include a base plate portion (321) and a hole portion (322).

[0073] The above base plate portion (321) is arranged on the upper surface of the body base portion (111) and can be combined with the body fastening portion (114). For example, the base plate portion (321) can cover the entire upper surface of the body base portion (111) by being screw-connected to four body fastening portions (114) and can maintain an electrical connection with the body fastening portions (114).

[0074] The above hole (322) can prevent contact with the connection terminal (200). For example, the hole (322) is positioned above the connection terminal (200), and even if the terminal fixing portion (220) is released and moves upward due to damage or loss of the terminal restraining portion (230), contact with the base plate portion (321) can be prevented, thereby preventing a short circuit from occurring.

[0075] Next, the circuit module (400) is a component that is mounted within the terminal block body (100), has a circuit line electrically connected to the connection terminal (200), and is configured to recover leakage current induced by the leakage current induction member (300).

[0076] The circuit module (400) includes a circuit board portion (410) in which each of the circuit lines of the cables (11, 12) and the three-phase, three-line leakage current recovery circuit portion (420) below is formed, and a leakage current recovery circuit portion (420) provided on the circuit board portion (410) and configured to recover leakage current induced in the leakage current induction member (300) to the power source side.

[0077] In the description below, a transformer (T) having three phases and three wires without a neutral wire on the secondary side is sufficient. The transformer (501) illustrated in FIG. 7, which is an embodiment of the leakage current recovery circuit unit (420), is a Y-△ transformer in which the three phases on the primary side are Y-connected and the three phases on the secondary side are △-connected. In addition, as illustrated in FIG. 8, a transformer (601) according to another embodiment of the leakage current recovery circuit unit (420) is a YY transformer in which the three phases on the primary side are Y-connected and the three phases on the secondary side are Y-connected. In addition, although not illustrated, a transformer according to another embodiment may be a △-△ transformer in which the three phases on the primary side are △-connected and the three phases on the secondary side are △-connected, or a △-Y transformer in which the three phases on the primary side are △-connected and the three phases on the secondary side are Y-connected. Here, three-phase means that the voltages of each phase are vr=sinwt, vs=sin(wt-120°), and vt=sin(wt-240°).

[0078] The above leakage current recovery circuit unit (420) includes, as an example, a power display unit (421) that displays an operating state including a power operation state of the terminal block and a normal operating state of the leakage current recovery circuit unit, as shown in FIG. 7, and a leakage current recovery unit (422) that recovers and processes leakage current induced by the leakage current induction member (300). In the present invention, the power display unit may be optionally included.

[0079] According to one embodiment of the present invention, the power display unit (421) may be arranged between any one of the three wires (RST) of the secondary side of the transformer and the leakage current induction member (300), including an LED that is forward-connected from the secondary side of the transformer toward the leakage current induction member (300).

[0080] According to another embodiment of the present invention, the power display unit (421) may be arranged between the three wires (RST) of the secondary side of the transformer and the leakage current induction member (300), including LEDs that are forward-connected in parallel from the secondary side of the transformer toward the leakage current induction member (300). Specifically, an eleventh resistor (R11), a first LED (LED1), and a first diode (D1) in series connection are arranged between the R line of the secondary side of the transformer and the leakage current induction member (300). A twelfth resistor (R12), a second LED (LED2), and a second diode (D2) in series connection are arranged between the S line of the secondary side of the transformer and the leakage current induction member (300). In addition, a thirteenth resistor (R13), a third LED (LED3), and a third diode (D3) in series connection are arranged between the T line of the secondary side of the transformer and the leakage current induction member (300). That is, one side of the power display unit (220) is connected to the R line, the S line, and the T line, respectively, and the other side of the power display unit (220) is commonly connected to the first common node (CN1). Accordingly, when power is applied to the secondary side of the transformer, the first to third LEDs (LED1, LED2, LED3) light up.

[0081] Here, the 11th to 13th resistors (R11, R12, R13) and the 1st to 3rd diodes (D1, D2, D3) are responsible for protecting the 1st to 3rd LEDs (LED1, LED2, LED3), respectively.

[0082] Continuing, the leakage current recovery unit (422) includes passive elements (e.g., resistors or inductors) connected in parallel between the three wires (RST) of the secondary side of the transformer and the leakage current induction member (300). Specifically, a 21st resistor (R21) is arranged between the R line of the secondary side of the transformer and the leakage current induction member (300). A 22nd resistor (R22) is arranged between the S line of the secondary side of the transformer and the leakage current induction member (300). In addition, a 23rd resistor (R23) is arranged between the T line of the secondary side of the transformer and the leakage current induction member (300). That is, one side of the 21st resistor (R21), the 22nd resistor (R22), and the 23rd resistor (R23) is connected to the R line, the S line, and the T line, respectively, and the other sides of the 21st resistor (R21), the 22nd resistor (R22), and the 23rd resistor (R23) are commonly connected to the second common node (CN2).

[0083] Here, the resistance values ​​(e.g., 100 ohms) of the 21st to 23rd resistors (R21, R22, R23) must be the same. When the three-phase voltage is in a balanced state, no current flows through the second common node (CN2) in the direction of the load (three-phase motor) or in the direction of the power source (transformer secondary side).

[0084] As another embodiment, when the 21st to 23rd inductors (L21, L22, L23) are used as passive components, the inductance values ​​of the 21st to 23rd inductors (L21, L22, L23) must be the same.

[0085] In the present invention, since the grounding of the terminal block is a third-class grounding (13), a grounding resistance value of less than 100 ohms exists between the grounding wire and the ground.

[0086] According to the present invention, the leakage current induction member (300) and the leakage current recovery unit (422) are electrically connected so that the resistance value between the second common node (CN2) of the leakage current induction member (300) and the leakage current recovery unit (422) can be maintained at 0.1 ohm or less. Accordingly, when leakage current occurs in the terminal block, most of the leakage current flowing in the terminal block flows toward the leakage current recovery unit (422).

[0087] According to the three-phase, three-wire, electric shock prevention terminal block having a leakage current recovery function according to the present invention as described above, a leakage current recovery unit is arranged between the secondary side of the transformer and the electrical equipment, so that the leakage current flowing in the electrical equipment can be recovered to the power supply side of the secondary side of the transformer, thereby providing a new three-phase, three-wire terminal block.

[0088] In addition, the present invention has the advantage of preventing electric shock accidents by preventing leakage current from flowing to the human body even if a person touches the terminal block that is not connected to the neutral line of a three-phase, three-wire system when the terminal block is submerged, and allowing electrical equipment to operate normally even during submersion.

[0089] The embodiments described in this specification and the attached drawings are merely illustrative of some of the technical concepts encompassed by the present invention. Therefore, the embodiments disclosed in this specification are intended to illustrate, rather than limit, the technical concepts of the present invention. Therefore, it is self-evident that the scope of the technical concepts of the present invention is not limited by these embodiments. All modifications and specific embodiments that can be easily inferred by those skilled in the art within the scope of the technical concepts contained in the specification and drawings of the present invention should be construed as being included within the scope of the rights of the present invention.

Claims

1. It is connected to the secondary side of a 3-phase 3-wire transformer without a neutral wire, and is a terminal block for connecting wires in the middle to supply power to the load. Terminal block body; A plurality of connection terminals provided on the above terminal body, each of which is connected to a cable including a three-phase, three-wire cable and an electric component cable for supplying power to an electric component; A leakage current induction member provided in the terminal block body and configured to induce leakage current generated in the terminal block; and A circuit module provided in the terminal body and configured to recover leakage current induced by the leakage current induction member; 3-phase, 3-wire, electric shock prevention terminal block.

2. In paragraph 1, The circuit module includes a circuit board portion, and a leakage current recovery circuit portion provided on the circuit board portion and configured to recover leakage current induced by the leakage current induction member to the power supply side. The above leakage current recovery circuit unit is characterized in that it includes a leakage current recovery unit that recovers and processes the leakage current induced by the leakage current induction member. 3-phase, 3-wire, electric shock prevention terminal block.

3. In paragraph 2, The above leakage current recovery unit A first passive element placed between the secondary R line of a three-phase, three-wire transformer without a neutral line and a leakage current induction member; A second passive element disposed between the secondary S-line of the transformer and the leakage current induction member; and A third passive element is characterized by including a third passive element arranged between the secondary T-line of the transformer and the leakage current induction member; 3-phase, 3-wire, electric shock prevention terminal block.

4. In paragraph 3, The above leakage current recovery circuit It is characterized in that it further includes a power display unit including an LED that is forward-connected from the secondary side of the transformer toward the leakage current induction member between the secondary side of the transformer and the leakage current induction member. 3-phase, 3-wire, electric shock prevention terminal block.

5. In paragraph 4, The above power display An 11th resistor and a 1st LED connected in series between the secondary R line of the above transformer and the leakage current induction member; A 12th resistor and a second LED connected in series between the secondary S line of the above transformer and the leakage current induction member; and A 13th resistor and a 3rd LED connected in series between the secondary T line of the above transformer and the leakage current induction member; A three-phase, three-wire, electric shock prevention terminal block including at least one series-connected resistor and LED.

6. In paragraph 5, The above terminal block body A body part including a body base part formed of an insulating material, a cable connection hole part formed on one side of the body base part and guiding the insertion of each of the cables, and a terminal mounting part formed on an upper portion of the body base part and communicating with the cable connection hole part and guiding the insertion of the connection terminal; and It is characterized by including a cover part provided on the upper and lower surfaces of the body part and configured to cover the leakage current induction member; 3-phase, 3-wire, electric shock prevention terminal block.

7. In paragraph 6, The above leakage current induction member It is characterized in that it is made of a conductor and is arranged to surround the connection terminal so as to induce a leakage current generated at the connection terminal. 3-phase, 3-wire, electric shock prevention terminal block.

8. In paragraph 5, The above terminal block body A body part including a body base part formed of an insulating material, a cable connection hole part formed on one side of the body base part and guiding the insertion of each of the cables, a terminal mounting part formed on an upper portion of the body base part and communicating with the cable connection hole part and guiding the insertion of the connection terminal, and a body fastening part that is insert-molded in the body base part and is exposed to the upper and lower portions of the body base part and is electrically connected to the leakage current induction member; and It is characterized by including a cover part provided on the upper and lower surfaces of the body part and configured to cover the leakage current induction member; 3-phase, 3-wire, electric shock prevention terminal block.

9. In paragraph 3, The first to third passive elements are characterized in that they are resistors or inductors. 3-phase, 3-wire, electric shock prevention terminal block.

10. In paragraph 9, The impedance values ​​of the first to third passive elements are characterized by being the same. 3-phase, 3-wire, electric shock prevention terminal block.

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