KR100928006B1 - Detecting device of leakage current in the flooded water - Google Patents

Abstract

PURPOSE: A detecting device of leakage current in the flooded water is provided to detect the presence of the leakage current generated at water logging of the power unit. CONSTITUTION: The leakage current detection sensor(110) senses the alternating current electric potential difference to be perpendicularly arranged. The transformer(120) includes the primary side coil and the secondary side coil and is electrically connected to the leakage current detection sensor. The energy low frequency filter(130) passes the ELF band of the voltage outputted from the leakage current detection sensor and is electrically connected to the secondary side coil. The multiplexer(140) shares to allocate signals of the low frequency filter and is electrically connected to the low frequency filter. The variable gain amplifier(150) amplifies the signal outputted from a multiplexer and is electrically connected to a multiplexer. The central processing unit(190) consecutively computes the signal intensity detected from the A/D converter and is electrically connected to the A/D converter.

Description

DETECTING DEVICE OF LEAKAGE CURRENT IN THE FLOODED WATER}

The present invention relates to a leakage current detection device present in the water surrounding the submerged power device, and more particularly, to detect the leakage current when the power control device such as underground junction boxes, street lamps, or signals buried around the road. A leak current detection device present in water around a submerged power device.

Recently, due to the aesthetics and safety of the city, the underground of electric power facilities installed on electric poles is progressing a lot. Accordingly, underground junction boxes for branching or connection of underground lines are often installed on roads with heavy traffic. However, recently, heavy rainfall due to extreme weather has frequently occurred, and the number of underground junction boxes is flooded every time. As the pedestrians passing near the low-voltage junction boxes (manholes), street lamps, or traffic lights flooded with heavy rains, electric shocks occur, water may accumulate on the streets of the city due to rainy or heavy rains. Pedestrians are walking with a little fear of electric shock due to short circuits when walking, and preventive measures are urgently needed.

The government and distribution companies have established mid- and long-term preventive measures to install insulated rubber plates in the low-voltage junction box and apply additional taping to wire connection points to prevent safety accidents.The junction box is used to prevent safety accidents caused by low-voltage junctions. Preventive measures against electric shocks have been implemented by replacing the cable connection points with waterproof connection materials and the material of the low voltage junction box lids with current high-strength (reinforced) plastic (FRP). Such preventive measures may significantly reduce the rate of electric shock in rainy weather, but do not fundamentally solve the electric shock. When the junction box is flooded with heavy rain, the possibility of electric shock cannot be completely excluded according to various situations.

The technical problem of the present invention is to check whether there is a leakage current flowing around a submerged underground junction box or an underground switchgear, so that leakage current exists in the water around a submerged power device that can determine the possibility of an electric shock accident of a pedestrian in advance. It is an object to provide a detection device.

Leakage current detection device present in the water surrounding the submerged power device to achieve the above technical object comprises a plurality of leakage current sensor for sensing the electric field vector of three axes; A transformer having a primary coil and a secondary coil, the transformer having a plurality of primary coils, each of the primary coils being electrically connected to each of the leakage current sensing sensors; A plurality of ultra low frequency filters configured to be electrically connected to each of the plurality of secondary coils and to pass only ELF bands of voltages output from the plurality of leakage current sensors; A multiplexer electrically connected to the plurality of ultra low frequency filters to allocate and share channels of each of the plurality of signals passing through the ultra low frequency filter; A variable gain amplifier electrically connected to the multiplexer to amplify the signal output from the multiplexer and to widen a dynamic range of the measured amount; An effective value conversion circuit electrically connected to the variable gain amplifier to convert a signal output from the variable gain amplifier into a direct current effective value; A DC amplifier electrically connected to the effective value conversion circuit to amplify the effective value voltage that has passed through the effective value conversion circuit; An A / D converter electrically connected to the DC amplifier to digitize an effective analog current output from the DC amplifier; And a central processing unit electrically connected to the A / D converter and continuously calculating the strength of the signal detected by the A / D converter. Characterized in that it is formed to include.

In addition, the leakage current detection device present in the water surrounding the submerged power device is further formed by a leakage current display device electrically connected to the central processing unit, in this case the central processing unit is Data may be output to the leakage current display device so as to be displayed on the leakage current display device.

In addition, the leakage current detection device present in the water around the submerged power device may further comprise a battery, the battery is the multiplexer (multiplexer), the variable gain amplifier, the effective value conversion circuit, the The DC amplifier, the A / D converter, the central processing unit, and the leakage current display device may be electrically connected to each other to supply DC power.

In addition, the leakage current detection device present in the water surrounding the submerged power device is further formed by a ground fault alarm device electrically connected to the central processing unit, in which case the central processing unit is a threshold value of the signal strength It may be detected that the above rises to notify the ground fault alarm device to generate an alarm sound in the ground fault alarm device.

On the other hand, the leakage current sensor comprises: a first sensing unit including a first conductive pad and a second conductive pad spaced in parallel with the first conductive pad; A second sensing part including a third conductive pad and a fourth conductive pad spaced apart from and parallel to the third conductive pad; A third sensing part including a fifth conductive pad and a sixth conductive pad spaced in parallel with the fifth conductive pad; And a sensor body made of a dielectric (insulator) that provides a seating space in which the first and second sensing units and the third sensing unit can be vertically attached to each other without overlapping each other. It may be formed to include.

In addition, the leakage current detection device present in the water surrounding the submerged power device is further formed by a GPS receiver that is electrically connected to the central processing unit, the GPS receiver is the position where the central processing unit is located Information about a local coordinate of may be transmitted to the central processing unit.

In addition, the leakage current detection device present in the water surrounding the submerged power device, the detection rod is attached to the leakage current sensor at one end; And an outer enclosure surrounding the multiplexer, the variable gain amplifier, the effective value conversion circuit, the DC amplifier, the A / D converter, and the central processing unit. It may be formed to further include.

The present invention can determine in advance the possibility of electric shock accidents of pedestrians walking around by checking the presence of leakage current in the water around the power facility such as submerged underground junction box, There is an effect that can prevent the electric shock of pedestrians or animals walking around.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the following description, the components constituting the leakage current detection device in the water around the submerged power device according to an embodiment of the present invention, the role of each of the components, and the coupling relationship between the components will be described. do.

1 is a block diagram of a leakage current detection device present in water around a submerged power device according to one embodiment of the invention. FIG. 2 is a perspective view of the leakage current sensor shown in FIG. 1. 3 is a perspective view of an application of the leakage current detection device present in the water around the submerged power device shown in FIG.

As shown in Figure 1 and 3, the leakage current detection device 100 present in the water around the submerged power device according to an embodiment of the present invention is a leakage current sensor 110, transformer 120, Ultra low frequency filter 130, multiplexer 140, variable gain amplifier 150, effective value conversion circuit 160, DC amplifier 170, A / D converter 180, and a central processing unit 190 Is formed. In addition, the leakage current detection device 100 present in the water around the submerged power device further includes a memory device 200, an electric leakage display device 210, a battery 220, and an electric leakage warning device 230. Is formed. In addition, the leakage current detection device 100 present in the water around the submerged power device is further formed by the GPS receiver 240. In addition, the leakage current detection device 100 present in the water around the submerged power device is formed by further comprising a detection rod 250 and the outer enclosure 260. Here, the enclosure 260 is a transformer 120, a very low frequency filter 130, a multiplexer 140, a variable gain amplifier 150, an effective value conversion circuit except for the leakage current sensor 110 shown in FIG. 160, the DC amplifier 170, the A / D converter 180, the central processing unit 190, the memory device 200, the leakage current display device 210, the battery 220, the earth leakage alarm device 230 And a GPS receiver 240.

The leakage current sensor 110 is formed to include a first detector 111, a second detector 112, a third detector 113, and a sensor body 114. Here, the leakage current sensor 110 serves to detect the potential difference in the air or in the water.

The first detector 111 is formed to include a first conductive pad 111a and a second conductive pad 111b.

The first conductive pad 111a is coupled to one surface of the sensor body 114.

The second conductive pad 111b is coupled to one surface of the sensor body 114 to be spaced apart in parallel with the first conductive pad 111a.

Here, the first detector 111 detects the potential difference between the first conductive pad 111a and the second conductive pad 111b.

The second detector 112 is formed to include a third conductive pad 112a and a fourth conductive pad 112b.

The third conductive pad 112a is coupled to one surface of the sensor body 114.

The fourth conductive pad 112b is spaced in parallel with the third conductive pad 112a and is coupled to one surface of the sensor body 114. In addition, the third conductive pad 112a and the fourth conductive pad 112b are coupled to the sensor body 114 so as not to overlap the first conductive pad 111a and the second conductive pad 111b.

Here, the second detector 112 detects the potential difference between the third conductive pad 112a and the fourth conductive pad 112b.

The third sensing unit 113 includes a fifth conductive pad 113a and a sixth conductive pad 113b.

The fifth conductive pad 113a is coupled to one surface of the sensor body 114.

The sixth conductive pad 113b is spaced apart in parallel with the fifth conductive pad 113a and is coupled to one surface of the sensor body 114. In addition, the fifth conductive pad 113a and the sixth conductive pad 113b may include the first conductive pad 111a, the second conductive pad 111b, the third conductive pad 112a, and the fourth conductive pad 112b. It is coupled to the sensor body 114 so as not to overlap.

Here, the third detector 113 detects a potential difference between the fifth conductive pad 113a and the sixth conductive pad 113b.

The sensor body 114 is formed of a cube in order to provide a seating space in which the first sensing unit 111, the second sensing unit 112, and the third sensing unit 113 are vertically attached to each other without overlapping each other. do. The sensor body 114 is formed of a dielectric material of a high insulator such as a ceramic or resin material.

The first detector 111, the second detector 112, and the third detector 113 of the leakage current sensor 110 are coupled to the sensor body 114 such that the central axes are perpendicular to each other. Each of the first detector 111, the second detector 112, and the third detector 113 is formed to form an X axis, a Y axis, and a Z axis in a three-dimensional space. As a result, the first detector 111, the second detector 112, and the third detector 113 can detect potential differences in three different vertical three-axis directions, where the sensor body 114 is placed. It serves to detect the electric field.

The transformer 120 includes a first transformer 121, a second transformer 122, and a third transformer 123. Here, the first transformer 121 is electrically connected between the first sensing unit 111 and the first ultra low frequency filter 131, and the second transformer 122 is connected to the second sensing unit 112 and the second pole. The low frequency filter 132 is electrically connected to each other, and the third transformer 123 is electrically connected between the third sensing unit 113 and the third ultra low frequency filter 133. Since the first transformer 121, the second transformer 122, and the third transformer 123 are formed in the same structure, they will be described in common in the present description.

The transformer 120 includes a primary coil and a secondary coil. In addition, the transformer 120 is composed of a plurality. In this case, the primary coils are electrically connected to each of the first detector 111, the second detector 112, and the third detector 113. In addition, the secondary coils are electrically connected to the multiplexer 140. Here, the transformer 120 is composed of a primary coil and a secondary coil to form a voltage by electromagnetic induction, and serves as impedance matching between the leakage current sensor 110 and the ultra low frequency filter 130, and also detects leakage current. It serves to insulate between the sensors 111, 112, 113.

Here, the electrical connection length between the leakage current sensor 110 and the transformer 120 may be made by the cable 11 is coated between 0.5 meters to 3 meters.

The ultra low frequency (ELF) filter 130 includes a first ultra low frequency filter 131, a second ultra low frequency filter 132, and a third ultra low frequency filter 133. Here, the first very low frequency filter 131 is electrically connected between the secondary coil of the first transformer 121 and the multiplexer 140, and the second very low frequency filter 132 is connected to the second transformer 122. The secondary coil and the multiplexer 140 are electrically connected, and the third ultra low frequency filter 133 is electrically connected between the secondary coil of the third transformer 123 and the multiplexer 140. The first ultra low frequency filter 131, the second ultra low frequency filter 132, and the third ultra low frequency filter 133 are formed in the same structure. The ultra low frequency filter 130 passes only the extremely low frequency (ELF) band in the frequency components of the voltages output from the plurality of leakage current sensors 110 to send to the multiplexer 140. That is, the ultra-low frequency filter 130 applies only the voltage of the frequency component of the voltage output from the leakage current sensor 110 to the multiplexer 140 in the vicinity of a frequency of 50 Hz to 60 Hz, which is a frequency of a commercial AC power supply. In order to prevent the detection error from occurring due to the noise component, the leakage current is detected.

The multiplexer 140 is electrically connected to the plurality of very low frequency filters 130 to share the output by allocating channels of the plurality of signals passing through the very low frequency filter 130.

Here, the multiplexer 140 splits the signal output from each ultra low frequency filter into two and receives the signal. One of the signal is 100% input, the other is divided by the first resistor (9R) and the second resistor (R) at a ratio of 10: 1 receives only 10% of the signal size. In this case, the switching path of the multiplexer 140 is adjusted by the central processing unit 190. If the strength of the signal is less than the first threshold value, the CPU 190 sends a control signal to the address line to receive the size of the signal as it is, and if the magnitude of the signal is the first threshold value, If greater, the central processing unit 190 sends a control signal to the address line (switch line) to switch to select the size of 10% of the signal size to pass to the variable gain amplifier 150. In this operation, a very small signal can be amplified without attenuation, and a very large signal can be attenuated at a 10% ratio, or the gain of the variable gain amplifier 150 is reduced to reduce the input / output size of the A / D converter 150. Make sure you are in the appropriate range. The central processing unit 190 determines the determination of all of these. In this case, the multiplexer 140 serves to sequentially send the signals output from the plurality of ultra-low frequency filters 130 to the variable gain amplifier 150, and the sequential driving is performed from the central processing unit 190. Is controlled by a plurality of lines.

The variable gain amplifier 150 is electrically connected to the multiplexer 140 to sequentially amplify the signals of the plurality of ultra low frequency filters 130 output from the multiplexer 140. The variable gain amplifier 150 serves to amplify the weak signal detected by the leakage current sensor 110 in order to convert it into an operable size for signal processing. In addition, the variable gain amplifier 150 lowers the gain of the variable gain amplifier 150 in the central processing unit 190 when the value of one axis detected among the detection units of the leakage current detection sensor 110 is large, and conversely, detects the leakage current. If the value of any one axis detected among the sensing units of the sensor 110 is small, the central processing unit 190 increases the gain of the variable gain amplifier 150 so that the effective value conversion circuit 160 is always operated in an optimal state. .

The effective value conversion circuit 160 is electrically connected to the variable gain amplifier 150 to convert a signal output from the variable gain amplifier 150 into a direct current effective value. The effective value conversion circuit 160 converts an AC signal into a DC signal in order to calculate the magnitude of the vector amount of the electric field (electric field) signals detected by the leakage current sensor 110.

The DC amplifier 170 is electrically connected to the effective value conversion circuit 160 to amplify the effective value current passed through the effective value conversion circuit 160.

The A / D converter 180 is electrically connected to the DC amplifier 170 to digitize the effective analog signal output from the DC amplifier 170. Here, the A / D converter 180 serves to digitize the central processing unit 190 to calculate the converted value.

The CPU 190 is electrically connected to the A / D converter 180 and continuously calculates the strength of the signal detected by the A / D converter 180 and converts the calculated signal strength to the leakage current value. Converting to a correct value, the leakage current display device 210 serves to visually display the leakage current value. In addition, when the intensity of the calculated signal increases above the threshold value, the central processing unit 190 sends a signal to the ground fault alarm device 230 and serves to inform the worker audibly.

Here, the central processing unit 190 associates and sequentially processes a signal sequentially transmitted from the leakage current sensor 110 to the A / D converter 180 as follows.

Where Vx = k * Ex, Vy = k * Ey, Vz = k * Ez, k is the conversion constant, Ex is the first sensing unit electric field size, Ey is the second sensing unit electric field size, and Ez is the third The electric field size of the detector.

The central processing unit 190 detects the voltage amount V as shown in Equation (1). In this way, the intensity (E) of the electric field (electric field) present in the space where immersion and leakage current (leakage) flows is expressed by Equation (2). In this case, as the leakage current increases, the strength E of the electric field (electric field) increases, and when a specific threshold is exceeded, an electric shock accident may occur to a pedestrian walking in the flooded area.

The memory device 200 is electrically connected to the central processing unit 190 to store data calculated by the central processing unit 190 and location information provided by the GPS receiver 240. Afterwards, the memory device 200 is connected to the computer PC to transmit all the contents detected by the leakage current detection device 100 to the computer PC so that the computer PC processes the contents. .

The leakage current display device 210 is electrically connected to the central processing unit 190. In this case, the central processing unit 190 outputs data such that the signal strength is displayed on the leakage current display device 210, and the leakage current display device 210 receiving the data visually displays the signal strength. .

The battery 220 includes a multiplexer 140, a variable gain amplifier 150, an effective value conversion circuit 160, a direct current amplifier 170, an A / D converter 180, a central processing unit 190, and a leakage amount. The display device 210 is electrically connected to each of the display devices 210 to supply DC power. Here, the battery 220 detects the leakage current present in the water around the submerged power device by supplying power to each of the components of the leakage current detecting device 100 present in the water surrounding the submerged power device. Allow the device 100 to be portable. Here, the battery 220 is a rechargeable battery, which is charged by the charger every time it is discharged.

The ground fault alarm device 230 is electrically connected to the central processing unit 190. In this case, the central processing unit 190 detects that the signal intensity rises above the threshold and notifies the ground fault alarm device 230, and the ground fault alarm device 230 receives a signal from the central processing unit 190. In this case, it plays an audible sound to the worker.

The GPS receiver 240 is electrically connected to the central processing unit 190 and transmits information about the local coordinates of the location where the system 100 is located to the central processing unit 190.

The detection rod 250 has a leakage current sensor 110 is coupled to one end. In addition, the detection rod 250 is formed of an insulating material, and is formed of a light and strong material so that the operator grasps the detection rod 250 so that it is easy to detect the earth leakage possible area. The detection rod 250 serves to conveniently detect the ground or the water without the risk of electric shock when the operator detects the leakage current.

The enclosure 260 includes a multiplexer 140, a variable gain amplifier 150, an effective value conversion circuit 160, a direct current amplifier 170, the A / D converter 180, and a central processing unit 190. Wrap In addition, the exterior enclosure 260 may further surround the leakage display device, the ground fault alarm device 230, and the GPS receiver 240. The outer enclosure 260 wraps the components of the leakage current detection device 100 present in the water around the submerged power device when the worker works on the detection of the leakage current, flooded with the detection rod 250 It serves to carry the leakage current detection device 100 present in the water around the power device.

In the following description, the operation and effects that occur when an operator drives a leakage current detection device present in water around a submerged power device according to an embodiment of the present invention will be described.

4 is a plan view showing a pole and underground junction box installed on a general road.

First, the worker carries the leakage current detection device 100 present in the water around the submerged power device in accordance with an embodiment of the present invention on a rainy day in which the power facility is flooded, the general road 14 The underground junction box 13 near the electric pole 12 installed in the vicinity of the () is probed by the leakage current detection device 100 present in the water around the submerged power device. In this case, the worker grabs the detection rod 250 by hand and detects the ground around the underground junction box 13 by the leakage current sensor 110 coupled to the detection rod 250.

At this time, when the leakage current flows around the underground junction box 13, the first detection unit 111, the second detection unit 112, the third detection of the leakage current detection sensor 110 of the detection rod 250 The unit 113 detects the leakage current by the potential difference of each conductive pad.

Then, the detected leakage current is applied to the primary coil of the transformer 120, and the primary coil of the transformer 120 magnetically induces the secondary coil.

Thereafter, the ultra low frequency filter 130 removes the noise component of the leakage current generated from the secondary side of the transformer 120 and transmits the noise component to the multiplexer 140.

Then, the multiplexer 140 sequentially sends the signals generated by the plurality of sensing units to the variable gain amplifier 150.

Next, the variable gain amplifier 150 sequentially amplifies the plurality of sensing signals and sends them to the effective value conversion circuit 160.

Then, the effective value converting circuit 160 converts the alternating current into an effective value and transmits the result to the DC amplifier 170.

Thereafter, the DC amplifier 170 amplifies the effective DC signal and transmits it to the A / D converter 180.

Next, the A / D converter 180 digitizes the amplified analog signal, and sequentially transmits the digitized signals to the CPU 190.

Then, the central processing unit 190 receives the digitized signal in sequence, calculates the sum and square root of the square, and calculates the intensity E of the calculated electric field (electric field) as shown in Equations 1 and 2. Is indicated at 210). At this time, the operator looks at the leak amount display device 210, and finds a place where the greater electric field strength is moved by moving the detection rod 250.

On the other hand, the central processing unit 190 stores the coordinates of the probe area and the electric field strength of the short-circuit display device 210 through the GPS receiver 240 in the storage device 200. This allows the operator to record the probe area coordinates along with the leaked electric field.

In the meantime, the central processing unit 190 detects that the strength E of the leakage electric field (electric field) has risen above the threshold value, and sends a signal to the ground fault alarm device 230. At this time, the ground fault alarm device 230 generates an alarm sound to inform the worker acoustically. Then, the operator detects the area in more detail, installs an electric shock hazard sign in the vicinity, lifts the lid of the flooded junction box 13, and puts the detection rod 250 into the junction box again to find a leakage current source. do. In this way, the maximum leakage current point (maximum electric field strength) is detected and found, and the operator takes a picture of the point and enters the procedure of closing the leakage current source after the water is drained from the submerged junction box.

Here, the leakage current detecting device 100 present in the water around the submerged power device is not limited to the underground junction box 13, and may be used in any device that uses electric power such as a street light or a traffic signal. In rainy situations such as flooding, flooding, and typhoons, it can be used for the safety of pedestrians or for the purpose of meter reading for the safety of emergency electricians.

In addition, the operator can perform the above-described probe work in each region of the country to read the leakage current amount of the corresponding area to prevent the electric shock accident of the pedestrian in advance.

       1 is a block diagram of a leak current detection device present in water around a submerged power device in accordance with one embodiment of the present invention.

2 is a perspective view of the leakage current sensor shown in FIG.

3 is a perspective view of a configuration example around the submerged power device shown in FIG. 1;

Figure 4 is a plan view showing a pole and underground junction box installed on a general road.

<Explanation of symbols for the main parts of the drawings>

110; Leakage current sensor 120; Transformer

130; Very low frequency filter 140; Multiplexer

150; Variable gain amplifier 160; Effective value conversion circuit

170; DC amplifier 180; A / D converter

190; Central processing unit 200; Memory

210; Leakage current display device 220; battery

230; Earth leakage alarm device 240; GPS receiver

250; Detection rod 260; Enclosure

Claims (6)

A plurality of leakage current sensors arranged perpendicularly to each other for detecting an AC potential difference; A transformer having a primary coil and a secondary coil, the transformer having a plurality of primary coils, each of the primary coils being electrically connected to each of the leakage current sensing sensors; A plurality of ultra low frequency filters configured to be electrically connected to each of the plurality of secondary coils and to pass only ELF bands of voltages output from the plurality of leakage current sensors; A multiplexer electrically connected to the plurality of ultra low frequency filters to allocate and share channels of each of the plurality of signals passing through the ultra low frequency filter; A variable gain amplifier electrically connected to the multiplexer and amplifying a signal output from the multiplexer; An effective value conversion circuit electrically connected to the variable gain amplifier to convert a signal output from the variable gain amplifier into a direct current effective value; A DC amplifier electrically connected to the effective value conversion circuit to amplify the effective value current passing through the effective value conversion circuit; An A / D converter electrically connected to the DC amplifier to digitize an effective analog current output from the DC amplifier; And A central processing unit electrically connected to the A / D converter and continuously calculating the intensity of the signal detected by the A / D converter; Leakage current detection device present in the water surrounding the submerged power device, characterized in that it is formed. The method of claim 1, And a leakage amount display device electrically connected to the central processing unit. And the central processing unit outputs data to the leakage current display device such that the signal intensity is displayed on the leakage current display device. The method of claim 1, It further comprises a ground fault alarm device electrically connected with the central processing unit, The central processing unit is present in the water around the flooded power device, characterized in that to detect the signal intensity rises above the threshold value to notify the ground fault alarm device to generate an alarm sound from the ground fault alarm device Leakage current detection device. The method of claim 1, The leakage current sensor A first sensing part including a first conductive pad and a second conductive pad spaced in parallel with the first conductive pad; A second sensing part including a third conductive pad and a fourth conductive pad spaced apart from and parallel to the third conductive pad; A third sensing part including a fifth conductive pad and a sixth conductive pad spaced in parallel with the fifth conductive pad; And A sensor body providing a seating space of a cube that is attachable to the first sensing unit, the second sensing unit, and the third sensing unit to be perpendicular to each other without overlapping each other; Leakage current detection device present in the water surrounding the submerged power device, characterized in that it is formed. The method of claim 1, It is formed further comprising a GPS receiving device electrically connected to the central processing unit, And the GPS receiver transmits information about the local coordinates of the location where the central processing unit is located to the central processing unit. The method of claim 1, A detection rod to which the leakage current sensor is attached at one end; And An outer enclosure surrounding the multiplexer, the variable gain amplifier, the effective value conversion circuit, the DC amplifier, the A / D converter, and the central processing unit; Leakage current detection device present in the water surrounding the submerged power device, characterized in that it further comprises.

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