KR20060091556A - Power control equipment for preventing electric shock cause - Google Patents

Abstract

When the leakage voltage over the set voltage is generated in the electric structures such as traffic lights and street lights installed on the road, the AC power is cut off to prevent the occurrence of safety accidents.

According to the present invention, a leakage voltage detection unit detects a leakage voltage for a voltage detected between an N phase and a pontoon of a power line, and a power cutoff signal generator generates a ground current when the leakage voltage detection unit detects a leakage voltage above a set level. In addition, when the set time has elapsed, the AC power is short-circuited, and the image current transformer detects the ground current generated by the power interruption signal generator, and the ground fault image detector detects the ground current. The AC switch is cut off by controlling the magnet switch.

Electrical structures, roads, electric shocks, flooding, overcurrents, interruptions, leakage voltages, pontoons

Description

Power protection device for electric shock protection {POWER CONTROL EQUIPMENT FOR PREVENTING ELECTRIC SHOCK CAUSE}

1 is a view showing the configuration of a conventional ground fault interrupting device,

2 is a circuit diagram showing the configuration of the ground fault interrupting device of the present invention;

3 is a circuit diagram showing the configuration of the leakage voltage and the immersion detection unit of FIG.

4 is a circuit diagram showing the configuration of an electric shock protection power cut-off device according to an embodiment of the present invention;

5 is a circuit diagram showing the configuration of the leakage voltage detecting unit 240 of FIG.

         Explanation of symbols on the main parts of the drawings

100: multiple pontoons 110: control panel

111: circuit breaker 113: magnet switch

115: power supply line 117: video current transformer

119: leakage image detector 200: leakage voltage and immersion detection unit

220, 221: leakage voltage detecting rod 222, 223: leakage voltage connection terminal

230: power cut off signal generator

231: operation signal generator 233: short circuit current generator

235: ground current generating unit 240: leakage voltage detection unit

300, 300A: leakage voltage detector 310: full-wave rectifier

320: operation power generator 330: reference voltage generator

340: leakage voltage determination unit 350: immersion determination unit

360: leakage voltage and submerged signal output unit

The present invention relates to an electric shock prevention device, and more particularly, to an electric shock protection device for preventing electric shock by cutting off the power when a leakage voltage of a set voltage or more is generated in an electric structure.

In general, when leakage current and leakage voltage flow to the outside of electric structures such as street lamps and traffic signals installed on roads, various industrial equipment used in factories and houses, bathroom outlets, washing machines, refrigerators, etc. In the event of flooding or flooding, the power supply must be shut off to prevent electric shock.

An electric shock accident prevention apparatus for cutting off power to prevent an electric shock accident when flooding occurs such as a street light and a traffic signal is shown in FIG. 1. Referring to FIG. 1, a plurality of iron bars 100 are supported and installed by a support 101 while maintaining a predetermined distance from each other on a road, and a traffic signal is displayed on an upper end of the plurality of iron bars 100. A lamp (not shown) for illuminating the road is installed.

And the control panel 110 for supplying and lighting the AC power (AC) to the lamp of the plurality of iron bars 100 is provided separately from the iron column (100).

The control panel 110 is a plurality of pontoons 100 through the circuit breaker 111 and the magnet switch 113 and the power supply line 115 that is automatically cut off when the AC power (AC) is supplied and the overcurrent flows. ), A zero-phase current transformer 117 is installed on the power supply line 115 of the output terminal of the magnet switch 113, and according to the output signal of the image current transformer 117, a grounded image detector 119 controls the circuit breaker 111 and the magnet switch 113 to cut off the AC power source AC.

The control panel 110 having such a configuration has an image current transformer 117 of the current flowing through the two power supply lines 115 when the AC power supply AC supplying to the iron column 100 through the power supply line 115 is leaked. The leakage detection is detected by the difference, and the leakage current detector 119 blocks the circuit breaker 111 and the magnet switch 113 according to the leakage detection signal of the image current transformer 117 to supply the alternating current 100 to the column 100. When AC is not supplied, and the overcurrent flows to the column 100 through the power supply line 115, the circuit breaker 111 detects the overcurrent and automatically cuts off the AC power. 100) It is not supplied to the side to prevent safety accidents due to short circuits.

In this electrical structure, the power supply line 115 is buried in the basement in the control panel 110 is typically extended to the lower portion of the plurality of iron column 100 is connected to the lamp of the upper end in the iron column (100) The power supply line 103 extends to the lower portion of the column 100 through the space portion in the column 100, and the power supply lines 115 and 103 are connected to each other and the circuit breaker 111 in the control panel 110. And AC power supplied through the magnetic switch 113 are sequentially applied to the lamp through the power supply lines 115 and 103.

In order to connect the power supply lines 115 and 103 to each other, the iron column 100 is typically provided with an opening and closing plate 105 at a height of about 50 cm from the ground, and through the opening and closing plate 105, an operator supplies the power supply line. After connecting (115) and (103) to each other, the connection portion 107 is insulated by taping with insulating tape or the like. When the iron column 100 as described above is submerged above the height of the connection portion 107 due to flooding, the AC power supplied through the power supply line 115, 103 to the insulating tape or the like. After taping, the water flows through the submerged water from the connection part 107, and this causes a safety accident in which pedestrians passing through adjacent positions of the iron column 100 are electrocuted. In order to prevent the electric shock accident, the control panel 110 is provided with an image current transformer 117 and an electric leak image detector 119 as described above to block the circuit breaker 111 and the magnet switch 113 when an electric leakage occurs. In addition, safety accidents such as electric shock accidents are prevented from occurring.

However, the power supply line 115 for supplying power from the control panel 110 to the iron column 100 is usually buried underground, and even if the power supply line 115 is insulated, it is very difficult to completely insulate, and practically, Some leakage occurs through the insulation of the power supply line 115 irrespective of immersion, and the image current transformer 117 and the leakage image detector 119 sensitively set the detection current for detecting the leakage. The circuit breaker 111 and the magnet switch 113 are blocked by a short circuit current flowing through the insulation part of the power supply line 115 to prevent the lamp 100 provided from the iron column 100 from operating normally.

Therefore, the image current transformer 117 and the ground fault image detector 119 are set to allow a slight leakage, that is, to block the circuit breaker 111 and the magnet switch 113 only when a leakage of more than a predetermined current is detected. As a result, safety accidents such as an electric shock due to a short circuit cannot be reliably prevented.

Therefore, the registered utility model No. 255182 (Application No. 2001-24190) registered and filed by the applicant in advance, installs an inundation detection rod for detecting the inundation of the iron column in the iron column, and relays when the inundation detection rod detects the inundation. The AC power source AC causes an overcurrent to flow through the contact, and the overcurrent is detected by the circuit breaker 111 of the control panel 110 to cut off the power supply.

However, the registered utility model No. 255182 has a short-circuit current flowing in the initial stage of short-circuit when the short-circuit means short-circuits AC power when flooding is detected, and the connection point of the short-circuit means is damaged by the short-circuit current. Therefore, there was a problem such as frequent replacement of relays, magnet switches, MCCB, and the like.

Ground fault protection device for solving this problem is disclosed in Korea Patent Publication No. 2004-41001. Publication 2004-41001 is disclosed in FIGS. 2 and 3.

2 is a circuit diagram showing the configuration of a conventional ground fault interrupting device.

As shown therein, the inundation detection rods 210 and 211 detect the inundation of the column 100 and the plurality of leakage voltage detection rods 220 and 221 to detect whether the leakage voltage or more than the set voltage leakage voltage or inundation detection The unit 200 and the leakage voltage and the submersion detection unit 200 generate a ground current when detecting the leakage voltage or more than the set voltage and short-circuit the AC power supply AC when the set time elapses. The circuit breaker 111 or the magnet switch 113 is provided with a power interruption signal generator 230 to block the AC power AC.

The power cutoff signal generator 230 is connected to the switch RYS1 while the relay RY1 is driven according to a control signal generated by the leakage voltage and the submersion detector 200 to generate a power cut operation signal. When the operation signal generator 231 and the operation signal generator 231 generate a power cut operation signal, the timer switch TA is driven and the relay RY2 when the set time of the timer switch TA has elapsed. Is driven, and its switches RYS21 and RY22 are connected, and a short-circuit current generator 233 for causing the AC power source AC to be short-circuited through the switches RYS21 and RYS22, and the operation signal generator 231 are powered. In the event of a blocking operation signal, the relay RY3 is driven and its switches RYS31 and RYS32 are connected to each other, and an earth fault current causes one side AC power supply AC to flow to the ground through the switches RYS31 and RYS32 to generate a ground current. The generator 235 is provided.

The immersion sensing rods 210 and 211 are installed at positions to detect immersion in the pontoon 100 so that the immersion sensing rods 210 and 211 are electrically connected to each other by the immersion water when the pontoon 100 is inundated. The leakage voltage sensing rods 220 and 221 are installed at a predetermined position to detect the leakage voltage, for example, at the basement 100 and a position spaced apart from the basement 100 to detect the leakage voltage leaked from the pillar 100. .

The ground fault interrupting device of the present invention configured as described above operates as an AC power supply AC supplied from the control panel 100 to the iron column 100 through the power supply line 115 to receive the leakage voltage and the immersion detection unit 200. The leakage voltage and immersion detection unit 200 determines whether the immersion detection rods 210 and 211 are flooded and electrically connected to each other, or whether the leakage voltage detection rods 220 and 221 detect a leakage voltage of a predetermined level or more, and determine As a result, when the submersion detection rods 210 and 211 are electrically connected to each other or when the leakage voltage detection rods 220 and 221 detect a leakage voltage of a predetermined level or more, a power cutoff control signal is generated to generate the power cutoff signal generator 230. It is applied to the timer switch TA of the short circuit current generator 233 and the relay RY3 of the ground current generator 235 through the switch RYS1 of the relay RY1 of the operation signal generator 231. The low timer switch TA is driven to count a predetermined time, and the relay RY3 is driven to connect the switches RYS31 and RYS32 thereof. Therefore, the power supply line 115 is disconnected from the control panel 110. AC power AC0 supplied to the column 100 through the ground current flows to the ground through the switch (RYS31, RYS32) of the relay RY3 is generated, the ground fault current generated by the current transformer 117 and the ground fault The image detector 119 detects the circuit breaker 111 and the magnet switch 113 to block the AC power supply AC, thereby preventing the occurrence of a safety accident.

The circuit breaker 111 and the magnet switch 113 do not detect the ground current because the current transformer 117 and the grounded image detector 119 do not detect the ground current even when the ground current is generated due to the switches RYS31 and RYS32 of the relay RY3 being connected. Does not cut off the AC power source AC and the relay RY2 is driven when the predetermined time set by the timer switch TA has elapsed, thereby connecting the switches RYS21 and RYS22 thereof.

Then, the steel AC power supply AC is short-circuited through the switches RYS21 and RYS22 of the relay RY2 so that a short circuit current flows, and the circuit breaker 111 detects the short circuit current to cut off the AC power AC. Prevent the occurrence of safety accidents.

FIG. 3 is a circuit diagram illustrating the leakage voltage and submersion sensing unit 200 of FIG. 2. As shown therein, the resistors R1 to R4 (R5 to R8), the variable resistors VR1 to VR2, and the diodes D1 and D2 to detect the voltages at both ends of the plurality of leakage voltage sensing rods 220 and 221, respectively. D4) and op amps OP1 and OP2, the leakage voltage detection unit 3000 (300A), the resistors R9 to R11 for full-wave rectification of the detected voltages of the leakage voltage detection units 300 and 300A, and operational amplification. (OP3), diodes (D5, D6), capacitors (C1, C2) and variable resistor (VR3) of the full-wave rectifier 310, and the AC power supply (AC) rectified and smoothed DC operating power supply (VCC, -VCC) ) Generates a reference voltage (VREF) detecting the immersion and leakage voltage to the operating power generating unit 320 and the operating power (VCC, -VCC) generated by the operating power generating unit 320 Whether a leakage voltage of a predetermined voltage or more is detected by the reference voltage generator 330 of (C5, C6), the reference voltage VREF generated by the reference voltage generator 330, and the output voltage of the full-wave rectifier 310 Of Leakage voltage determination unit 340 of the resistor (R15 ~ R17), the operational amplifier (OP4) and the diode (D7) to determine the negative, and the reference voltage (VREF) is applied to the immersion sensing rod 211 and according to the immersion An immersion determining unit 350 including variable resistors VR4, resistors R18 and R19, operational amplifiers OP5, and diodes D8 that determine whether the immersion is caused by the voltage change of the immersion sensing rods 210 and 211; Resistor R20 to R22 for operating the power cutoff signal generator 230 when the leakage voltage determiner 340 determines the detection of a leakage voltage of a predetermined voltage or more, or when the submersion determiner 350 determines the inundation. And a leakage voltage and submerged signal output unit 360 formed of a transistor TR and a photo coupler PC.

The leakage voltage and immersion detection unit 200 of the ground fault breaker configured as described above has AC power supplied from the control panel 110 to the iron column 100 through the power supply line 115 and the leakage voltage and immersion detection unit 200. Is applied to the primary coil of the transformer (T) of the operating power generating unit 320 and step-down output to the secondary coil, bridge rectified through the bridge diode (BD), smoothing and operating power by the capacitor (C3, C4) (VCC, -VCC) is generated and supplied to each part of the leakage voltage and the immersion detection unit 200.

The operation power sources VCC and -VCC generated by the operation power generation unit 320 are applied to the constant voltage diodes ZD1 and ZD2 through the resistors R12 and R13 of the reference voltage generation unit 330, thereby providing a constant voltage diode ZD1, The constant voltage of ZD2) is generated as the reference voltages VREF and -VREF, and the generated reference voltage -VREF is applied to the immersion sensing rod 210 through the resistor R14.

The reference voltage VREF is applied to the inverting input terminal (−) and the immersion sensing rod 210 of the operational amplifier OP5 through the variable resistor VR4 of the immersion determining unit 350.

In this state, when the pontoon 100 is not immersed, the immersion sensing rods 210 and 211 are opened to each other, and the reference voltage VREF is inverted of the operational amplifier OP5 through the variable resistor VR4. Since it is applied to the input terminal (−), the operational amplifier OP5 outputs a low potential, and thus a low potential is applied to the base of the transistor TR of the leakage voltage and the submerged signal output unit 360. ) Is not turned on, and the photo coupler PC does not operate, so that the relay RY1 of the operation signal generator 231 of the power cutoff signal generator 230 is not driven.

When the pontoon 100 is flooded, the immersion sensing rods 210 and 211 are electrically connected to each other through the flooded water, and the reference voltages VREF and -VREF are connected by the resistor R14 and the variable resistor VR4. It is divided and applied to the inverting input terminal (-) of the operational amplifier OP5.

Here, if the value of the variable resistor VR4 is set so that the voltage applied to the inverting input terminal (-) of the operational amplifier PO5 becomes a negative voltage when the pontoon 100 is flooded, the operational amplifier OP5 is high. Will print the above. Then, the high potential is applied to the base of the transistor TR of the leakage voltage and the submerged signal output unit 360, the light emitting part of the photocoupler PC is turned on, and the light receiving part receives the light. Is brought into a conductive state, and the AC power source AC is applied to the relay RY1 of the operation signal generator 231 of the power cutoff signal generator 230 through the light receiving unit of the photocoupler PC, thereby relay RY1. Since is driven, the switch RYS1 of the relay RY1 is connected as described above, and the short circuit current generator 233 and the ground current generator 235 operate to cut off the AC power source AC.

On the other hand, the resistors R1 and R2 (R35 and R6) and the variable resistors VR1 and VR2 of the leakage voltage detectors 300 and 300A are divided and operated by the diodes D1 and D2 (D3 and D4). After the level is limited between the power sources VCC and -VCC, the voltage is applied to the inverting input terminal (-) of the operational amplifier OP1 and OP2 to be amplified and amplified, and the full-wave rectification view 310 is provided through the resistors R4 and R5. Is applied to the inverting input terminal (-) of the operational amplifier OP3.

Then, the full-wave rectifying unit 310 negatively full-wave rectifies the leakage voltage detected by the leakage voltage detecting unit 300 (300A) and applies it to the inverting input terminal (-) of the operational amplifier OP4 of the leakage voltage determining unit 340. do.

In this case, when the leakage voltage detecting rods 220 and 221 detect less than the set leakage voltage, the value of the variable resistor VR3 is set such that the voltage output from the full-wave rectifying unit 310 is lower than the reference voltage VREF. A positive voltage is applied to the inverting input terminal (-) of the operational amplifier OP4 of the leakage voltage determining unit 340, and a low potential is output to the output terminal thereof.

Then, since the low potential is applied to the base of the transistor TR of the leakage voltage and the submerged signal output unit 360, the transistor TR is not turned on, and the photocoupler PC does not operate so that the power cutoff signal generator 230 is applied. Relay RY1 of the operation signal generator 231 is not driven. On the contrary, when the leakage voltage detecting rods 220 and 221 detect an abnormal leakage voltage, the voltage output from the full-wave rectifying unit 310 is higher than the reference voltage VREF in contrast to the above, so that the leakage voltage determining unit 34 Since a negative voltage is applied to the inverting input terminal (−) of the operational amplifier OP4, the operational amplifier OP4 outputs a high potential.

Then, the high potential is applied to the base of the transistor TR of the leakage voltage and the submerged signal output unit 360, the light emitting unit of the photocoupler PC is turned on, and the light receiving unit receives the light. Is turned on and the AC power source AC is applied to the relay RY1 of the operation signal generator 221 of the power cutoff signal generator 230 through the light receiving unit of the photocoupler PC so that the relay RY1 is applied. Since it is driven, the switch RYS1 of the relay RY1 is connected as described above, and the short circuit current generator 233 and the ground current generator 235 operate to cut off the AC power source AC.

Leakage voltage detection rods 220 and 221 of the conventional ground fault interrupting device as described above are installed at a predetermined position, for example, the pontoon 100 and a predetermined distance from the basement to detect the leakage voltage from the pontoon 100. Make sure to detect leaking leakage voltage. The leakage voltage detecting rod 220 is connected to the iron column 100, and the leakage voltage detecting rod 221 is buried so that the middle of the wire does not break down in the basement at a position spaced apart from the iron column 100. When an insulation breakdown occurs in the middle of the wire connected to the voltage sensing rod 221, the leakage voltage may not be detected when a short circuit occurs.

Therefore, an object of the present invention is to detect the leakage voltage between the N-phase and the iron column of the AC power supply even if the insulation breaks in the middle of the wire connected to the leakage voltage sensing rod, the power cut-off device for electric shock protection to cut off the AC power if it exceeds the allowable limit voltage In providing.

Hereinafter, preferred embodiments of the present invention will be described in detail. And in describing the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, with reference to the accompanying drawings of FIGS. 1 and 4 and 5 will be described in detail the electric shock protection power cut-off device of the present invention, where the same parts as in the prior art.

4 is a circuit diagram showing the configuration of an electric shock protection power cut-off device according to an embodiment of the present invention.

Leakage voltage sensing rods 220 and 221 for detecting voltage caused by a short circuit are embedded in the basement to prevent insulation breakdown in the basement spaced apart from the pontoon and connected to the N phase and the pontoon of the power supply line, respectively. Leakage voltage connection terminals 222 and 223 for detecting a leakage voltage due to a short circuit, and whether leakage voltages higher than a set voltage are generated from the leakage voltage detection rods 220 and 221 or the leakage voltage connection terminals 222 and 223. When the leakage voltage detection unit 240 and the leakage voltage detection unit 240 detect a leakage voltage above the set voltage, a ground current is generated and when the set time elapses, the AC power supply AC is short-circuited for wiring. The breaker 111 or the magnet switch 113 is provided with a power cutoff signal generator 230 to block the AC power AC.

The power cutoff signal generator 230 is an operation signal for generating a power cut operation signal by connecting a switch RYS1 thereof while the relay RY1 is driven according to a control signal generated by the leakage voltage detector 240. When the generator 231 and the operation signal generator 231 generate a power off operation signal, the timer switch TA is driven and the relay RY2 is activated when the set time of the timer switch TA has elapsed. A short-circuit current generator 233 for driving the switch RYS21 and RY22 thereof to be connected and the AC power source AC to be short-circuited through the switches RYS21 and RYS22, and the operation signal generator 231 cut off the power. When a signal is generated, a ground fault current generator for driving a relay (RY3) to connect its switches (RYS31 and RYS32) and connecting one AC power supply (AC) to ground through the switches (RYS31 and RYS32) to generate a ground current. 235 is provided.

The leakage voltage sensing rods 220 and 221 are installed at a predetermined position for detecting the leakage voltage, for example, at the basement 100 and at a position spaced apart from the basement 100 to detect the leakage voltage leaked from the pillar 100.

The electric shock protection power cut-off device of the present invention configured as described above operates by receiving the AC voltage AC supplied from the control panel 100 to the iron column 100 through the power supply line 115. The leakage voltage detecting unit 240 determines whether to detect a leakage voltage of a predetermined level or more set by the leakage voltage detecting rods 220 and 221 or the leakage voltage connecting terminals 222 and 223. Or when a leakage voltage of a predetermined level or higher is detected from the leakage voltage connection terminals 222 and 223, a power cutoff control signal is generated to relay the relay RY1 of the operation signal generator 231 of the power cutoff signal generator 230. Is applied to the timer switch TA of the short-circuit current generator 233 and the relay RY3 of the ground current generator 235 through the switch RYS1 of the timer. Time to car The relay RY3 is driven and its switches RYS31 and RYS32 are connected. Therefore, AC power AC0 supplied from the control panel 110 to the iron column 100 through the power supply line 115 is supplied. A ground fault current flowing to the ground is generated through the switches RYS31 and RYS32 of the relay RY3, and the image fault transformer 117 and the ground fault image detector 119 detect the generated ground fault current and the circuit breaker 111. And the magnet switch 113 is to cut off the AC power (AC), to prevent the occurrence of a safety accident.

The circuit breaker 111 and the magnet switch 113 do not detect the ground current because the current transformer 117 and the grounded image detector 119 do not detect the ground current even when the ground current is generated due to the switches RYS31 and RYS32 of the relay RY3 being connected. Does not cut off the AC power source AC and the relay RY2 is driven when the predetermined time set by the timer switch TA has elapsed, thereby connecting the switches RYS21 and RYS22 thereof.

Then, the steel AC power supply AC is short-circuited through the switches RYS21 and RYS22 of the relay RY2 so that a short circuit current flows, and the circuit breaker 111 detects the short circuit current to cut off the AC power AC. Prevent the occurrence of safety accidents.

5 is a circuit diagram illustrating a configuration of the leakage voltage detector 240 of FIG. 4.

As shown therein, the first leakage includes resistances R1 to R4, variable resistors VR1, diodes D1 and D2, and operational amplifiers OP1 that detect voltages at both ends of the leakage voltage connection terminals 222 and 223. Second leakage including the voltage detector 300 and the resistors R5 to R8 for detecting the voltage across the leakage voltage sensing rods 220 and 221, the variable resistor VR2, the diodes D3 and D4, and the operational amplifier OP2. Resistors R9 to R11, operational amplification OP3, diodes D5 and D6 for negative full-wave rectification of the voltage detector 300A and the detected voltages of the first and second leak voltage detectors 300 and 300A, Full-wave rectifier 310 composed of capacitors C1 and C2 and variable resistor VR3, and resistors R15 to R17 that determine whether a leakage voltage equal to or greater than a set voltage is detected by the output voltage of the full-wave rectifier 310. ), The leakage voltage determination unit 340 composed of the operational amplifier OP4 and the diode D7, and the leakage voltage determination unit 340 detects the leakage voltage of the set voltage or more. In this case, it is composed of a resistor (R20 ~ R22), the transistor (TR) and the photocoupler (PC) for the leakage voltage and submerged signal output unit 360 to operate the power cutoff signal generator 230.

The leakage voltage detection unit 240 of the electric shock protection power cut-off device of the present invention configured as described above is connected to a rectifier (AC) supplied from the control panel 110 to the iron column 100 through the power supply line 115. As a result, operating power sources VCC and -VCC are generated and supplied to each part of the leakage voltage unit 240.

The resistors R1 and R2 (R35 and R6) and the variable resistors VR1 and VR2 of the first and second leakage voltage detectors 300 and 300A are divided into diodes D1 and D2 (D3 and D4). After the level is limited between the operating power sources VCC and -VCC, it is applied to the inverting input terminal (-) of the operational amplifier OP1 (OP20) to be buffered and amplified, and the full wave rectification view (R4) through R5 is performed. It is applied to the inverting input terminal (-) of the operational amplifier OP3 of 310.

Then, the full-wave rectifying unit 310 negatively full-wave rectifies the leakage voltage detected by the leakage voltage detecting unit 300 (300A) and applies it to the inverting input terminal (-) of the operational amplifier OP4 of the leakage voltage determining unit 340. do.

The voltage output from the full-wave rectifier 310 may be lower than the reference voltage VREF when detecting the leakage voltage below the set leakage voltage from the leakage voltage sensing rods 220 and 221 or the leakage voltage connection terminals 222 and 223. When the value of the resistor VR3 is set, a positive voltage is applied to the inverting input terminal (-) of the operational amplifier OP4 of the leakage voltage determining unit 340 and a low potential is output to the output terminal thereof.

Then, since the low potential is applied to the base of the transistor TR of the leakage voltage signal output unit 360, the transistor TR is not turned on and the photocoupler PC does not operate so that the power cutoff signal generator 230 The relay RY1 of the operation signal generator 231 is not driven. On the contrary, when the leakage voltage abnormality is detected from the leakage voltage sensing rods 220 and 221 or the leakage voltage connection terminals 222 and 223, the voltage output from the full-wave rectifier 310 is the reference voltage VREF. Since the negative voltage is applied to the inverting input terminal (-) of the operational amplifier OP4 of the leakage voltage determining unit 34, the operational amplifier OP4 outputs a high potential.

Then, the high potential is applied to the base of the transistor TR of the leakage voltage signal output unit 360, the light emitting portion of the photocoupler PC is turned on, and the light receiving portion receives the light, so the light receiving portion of the photocoupler PC is turned on. AC power is applied to the relay RY1 of the operation signal generator 221 of the power cutoff signal generator 230, and the relay RY1 is driven. As described above, the switch RYS1 of the relay RY1 is connected, and the short circuit current generator 233 and the ground current generator 235 operate to cut off the AC power source AC.

Therefore, even if the insulation breakdown of the wire connected to the leakage voltage detection rods 220 and 221 occurs, it is possible to prevent an electric shock accident due to an overcurrent caused by a short circuit by detecting a leakage voltage between the N phase and the iron column of the power supply line.

On the other hand, while the present invention has been shown and described with respect to specific preferred embodiments, various modifications and variations of the present invention without departing from the spirit or field of the invention provided by the claims below It can be easily understood by those skilled in the art. As described by way of example, the present invention is not limited thereto, and the AC power may be cut off when the voltage detected between the N-phase and the iron column of the power supply line as well as the leakage voltage detection rod is detected as a leakage voltage higher than the set level. It may be modified in various ways.

As described above, the present invention is to embed the leakage voltage detection rod to detect whether the leakage voltage of a predetermined voltage or more in the electrical structure installed on the road to detect the leakage voltage of a predetermined level or more from the leakage voltage detection rod to cut off the AC power supply. In addition, if the insulation breakdown of the wire connected with the leakage voltage sensing rod occurs, the leakage voltage between the N-phase and the iron pole of the power supply line is sensed, and the control panel shuts down the AC power when a leakage voltage of a predetermined level or more occurs. It is possible to prevent the occurrence of electric shock due to the leakage voltage of the structure.

Claims (4)

Leakage voltage detection unit for detecting whether the leakage voltage between the N-phase and the iron column of the power supply line occurs a set voltage abnormality; A power cut-off signal controller which generates a ground current when the leakage voltage is detected from the leakage voltage detector and sequentially generates a short circuit current whenever a set time elapses; An image current transformer configured to detect a ground current and a short circuit current generated from the power interruption signal generator; A leakage image detector for controlling the AC power supply to be cut off when the image current transformer detects a ground current and a short circuit current; A circuit breaker that cuts off the AC power under control of the ground fault image detector and cuts off the AC power when the power cut-off control unit synthesizes the AC power; And And a mark net switch to cut off the AC power according to the control of the ground fault image detector. According to claim 1, The leakage voltage detection unit; A leakage voltage detector for detecting voltages at both ends of the leakage voltage connection terminal respectively connected to the N phase and the iron column of the power supply line; A full-wave rectifier for negative full-wave rectification of the detected voltage of the leakage voltage detector; And a leakage voltage determination unit configured to receive a negative full-wave rectified voltage and a reference voltage VREF outputted from the full-wave rectifying unit and compare the preset voltage with a preset reference voltage to determine a leakage voltage state. The method of claim 2, The leakage voltage detection rod is a power supply for electric shock protection, characterized in that the one rod is embedded in the ground of a position spaced apart from the pontoon and the other rod is connected to the pontoon. The method of claim 3, And the leakage voltage connection terminal has one end connected to the N phase of the power supply line and the other end connected to the pontoon.

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