KR100344088B1 - A Miss Wiring Detecting Device Of 3 Phase 4 Wire Type Power Meter - Google Patents

Abstract

A voltage detector means (130) connected between the three-phase four-wire meter and the MOF to determine whether the voltage terminals (P1, P2, and P3) are connected correctly or incorrectly; A P0 controller (150) comprising a plurality of NAND gate combinations for determining whether the common terminal (P0) is right or wrong; A first LED 170 displaying the determination result of the detector means 130 and the determination result of the P0 controller 150, respectively; Current detector means (200) connected to the MOF (18) to determine whether the respective current terminals (1S, 2S, 33) are positive or incorrect; Comparator means (220) connected in series with the current detector means (200) for amplifying and comparing the signal from the current detector means (200); Second LEDs 240 respectively displaying the determination results of the comparator means 220; Conversion means (302) for detecting a sine wave from each of the voltage terminals (P1, P2, P3) and the current terminals (1S, 2S, 33) and converting the sine wave into a real wave; A microcomputer (320) for inputting the embodied wave by the converting means (302) to determine whether the phase terminals are correctly or misaligned according to an input period of the embodied wave; And a third LED 340 which displays the determination result of the microcomputer 320, and indicates whether the wiring is correct or incorrect with the LED and the alarm.

Description

Mis-wiring detection device of three-phase four-wire meter {A Miss Wiring Detecting Device Of 3 Phase 4 Wire Type Power Meter}

The present invention relates to a sensing circuit for detecting the correct connection of the wiring, and more particularly, a wiring between a three-phase four-wire meter and a metering out fit (MOF) used in a place where a large amount of power is required, such as a factory. The present invention relates to an incorrect wiring detection device for a three-phase four-wire meter that detects whether ten wirings are correctly wired by a circuit device.

Since the meter 1 cannot measure the high power consumption directly, the MOF 2 operates at currents of 110V and 5A or less, and indirectly multiplies the measurement by a certain ratio (X3, X4, etc.). Used to measure. 1 is a schematic wiring diagram of a conventional three-phase four-wire meter and a MOF. As shown in FIG. 1, there are three transformers PT1, PT2, PT3 inside the MOF 2, and three current transformers CT1, CT2, CT3 are present in each transformer PT1, PT2, PT3. It is connected.

Since it is a three-phase four-wire meter (1), the meter (1) and the MOF (2) have three voltage terminals (P1, P2, P3), three current terminals (1S, 2S, 3S), and three phases. A total of ten terminals are provided, including the common terminals P0 through which the terminals 1L, 2L, and 3L and the voltage terminals P1, P2, and P3 are commonly grounded. As shown in FIG. 1, the ten terminals are connected so as to correspond to the ten terminals of the meter 1 by 1: 1 from the MOF 2.

However, due to the large number of wires and the complicated installation work, there was often an error of incorrect wiring connection during the installation and wiring work of the meter 1 and the MOF 2. As an example of such a miswiring, the cross wiring which connects P1 of the MOF 2 to P2 of the meter 1, and connects P2 of the MOF 2 to P1 of the meter 1 is mentioned. The cross wiring is not limited between the voltage terminals, but between the voltage terminals P1, P2, and P3, the current terminals 1S, 2S, and 3S, the phase terminals 1L, 2L, and 3L, and the common terminal P0. It can happen with a worker's momentary mistake or judgment.

As a result of this miswiring, the meter 1 may rotate counterclockwise, stop, or rotate at a slower speed than rated. By the way, in the case of reverse rotation, the operator or the like can easily recognize it. However, if the meter is stopped or the meter is rotated at a slow speed, it is judged as normal, so it is not easy to determine whether the wiring is correct or incorrect. In particular, there was no way to detect a phase change when the phases were changed due to cross wiring of the phase terminals 1L, 2L, and 3L.

In addition, in the case of digital meters which are increasingly used in recent years, there is a disadvantage that it is more difficult to recognize the miswiring than an analog meter because the display number changes every predetermined time.

In addition, even if the construction is completed by normal wiring, even if some of the ten lines are broken due to aging or external factors, because the meter (1) operates as described above, there was a problem that you can not immediately know the failure.

The present invention has been made in order to solve the above problems, the first object of the present invention is a three-phase four-wire type installed in a stationary type between the meter and the MOF to determine whether 10 wiring is miswired It is to provide an incorrect wiring detection device of a meter.

In addition, the second object of the present invention is the presence or absence of incorrect wiring of each voltage terminal (P1, P2, P3), each current terminal (1S, 2S 3S), each phase terminal (1L, 2L, 3L) and common terminal (P0) It is to provide a miswiring detection device for a three-phase four-wire meter that detects and displays independently.

In addition, a third object of the present invention is to detect whether the wiring of each phase terminal (1L, 2L, 3L) by the microcomputer, and whether the common terminal (P0) is incorrectly connected to the voltage terminals (P1, P2, P3) It is to provide a miswiring detection device for a three-phase four-wire meter that can detect and display independently.

Objects of the present invention as described above, three voltage terminals (P1, P2, P3), three current terminals (1S, 2S, 33), three phase terminals (1L, 2L, 3L) and common terminal (P0) 3-phase 4-wire meter 10 having a; And three current terminals P1, P2, and P3, three current terminals 1S, 2S, and 33, three phase terminals 1L, 2L, and 3L, and a common terminal P0. In a MOF 18 having transformers PT1, PT2, PT3 corresponding to CT1, CT2, CT3 and the current transformers CT1, CT2, CT3, respectively, between the meter 10 and the MOF 18; It is installed on, it is determined whether each voltage terminal of the MOF (18) is connected to correspond to each voltage terminal of the meter 10, respectively, and each current terminal of the MOF (18) is the meter 10 Determine whether each of the phase terminals of the MOF 18 are connected to correspond to each of the phase terminals of the meter 10, and determine whether each of the phase terminals of the MOF 18 Determination and display means (14) for determining whether the common terminal is connected to the common terminal of the meter (10) to display whether the wiring is correct or incorrect; It is achieved by a miswiring detection device of a three-phase four-wire meter.

The determination and display means (14) further includes: voltage detector means (130) connected to the MOF (18) to determine whether the voltage terminals (P1, P2, P3) are positive or incorrect; A P0 controller (150) comprising a plurality of NAND gate combinations for determining whether the common terminal (P0) is right or wrong; A first LED 170 displaying the determination result of the detector means 130 and the determination result of the P0 controller 150, respectively; Current detector means (200) connected to the MOF (18) to determine whether the respective current terminals (1S, 2S, 33) are positive or incorrect; Comparator means (220) connected in series with the current detector means (200) for amplifying and comparing the signal from the current detector means (200); Second LEDs 240 respectively displaying the determination results of the comparator means 220; Conversion means (302) for detecting a sine wave from each of the voltage terminals (P1, P2, P3) and the current terminals (1S, 2S, 33) and converting the sine wave into a real wave; A microcomputer (320) for inputting the embodied wave by the converting means (302) to determine whether the phase terminals are correctly or misaligned according to an input period of the embodied wave; And a third LED 340 displaying the determination result of the microcomputer 320.

In addition, a power supply 100 is further provided between the MOF 180 and the voltage detector means 130. The power supply 100 includes: a transformer 101 connected to voltage terminals P1 and PO; A bridge circuit 103 connected in series with the transformer 101; An amplifier circuit 105 connected in series with the bridge circuit 103; And a comparison circuit 107 connected in series with the amplification circuit 105.

In addition, the voltage detector unit 130 is provided for each of the voltage terminals P1, P2, and P3, and the detector unit 130 has the voltage input to the "+" side and the zener to the "-" side. A comparator 131 to which a diode 137 is connected; A resistor 140 having one end connected in series with an output terminal of the comparator 131; A transistor 139 having a base connected to the other end of the resistor 140, an emitter grounded, and a collector connected to the input side of the resistor 142 and the NOT gate 133, respectively; It is preferable to include.

The P0 controller 150 includes: a bridge circuit 151 having one side connected in parallel with each of the voltage terminals P1, P2, and P3, and the other side connected with the common terminal P0; A zener diode 155 and a resistor 156 connected in series with the bridge circuit 151; A transistor 157 having a base connected to the resistor 156, an emitter grounded, and a collector connected to a DC power source through a resistor R; A first NAND gate 158 having a first input signal connected to the collector of the transistor 157 and a second wiring signal 167 of each of the voltage terminals P1, P2 and P3 connected in parallel; A second NAND gate 159, wherein a first input and a second input are connected with a first input of the first NAND gate; A third NAND gate 160 connected with a first input and a second input to a second input of the first NAND gate; A fourth NAND gate 162 having an output of the second NAND gate 159 and an output of the third NAND gate 160 as inputs, respectively; A resistor 163 and a diode 164 connected in series between the output of the fourth NAND gate 162 and the output of the first NAND gate 158; A transistor (165) having a base connected between the resistor (163) and the diode (164), a collector connected to a DC power supply through a resistor (R), and an emitter grounded; And a NOT gate 166 which receives an emitter of the transistor 165 as an input.

Each of the first LED 170, the second LED 240, and the third LED 340 may include: an LED 172 and 173 having a second terminal grounded through a resistor 174; And a NOT gate 171 connected between the first terminal and the third terminal of the LEDs 172 and 173, thereby providing green light emission 172 when the wiring is normal and red light emission 173 when the wiring is incorrect. More preferred.

Third terminals of each of the first LED 170, the second LED 240, and the third LED 340 are connected in parallel to be connected to switch the alarm 400. Most preferably, the alarm 400 generates a warning sound when either the second LED 240 or the third LED 340 emits red light.

In addition, the microcomputer 320 may be programmed to determine that the input period of the implementation wave is normal when it is in the range of 5.5 to 5.6 ms, and to determine that it is a miswiring when the period is outside the range.

1 is a schematic wiring diagram of a conventional three-phase four-wire meter and a MOF,

Figure 2 is a schematic structural diagram showing the installation and mutual wiring relationship of the three-phase four-wire meter, MOF and terminal box according to an embodiment of the present invention,

3 is a block diagram illustrating the inside of the terminal box of FIG. 2 as a schematic block;

FIG. 4 is a circuit diagram illustrating one of the power supplies connected to each of the voltages P1, P2, and P3 terminals of FIG. 3;

5 is a circuit diagram of a voltage detector connected in series with the power supply circuit of FIG.

FIG. 6 is a circuit diagram common to the first LED 170, the second LED 240, and the third LED 340 of FIG. 3;

7 is a circuit diagram of the P0 controller 150 of FIG.

FIG. 8 is a circuit diagram illustrating one of the current detectors 200 connected to each of the current 1S, 2S, and 3S terminals of FIG. 3;

9 is a circuit diagram of a comparator 220 connected in series to the current detector 200 of FIG.

FIG. 10 is a circuit diagram illustrating a phase detector of only P1-1S, omitting phase detectors for P2-2S and P3-3S among the phase detectors 300 of FIG.

FIG. 11 is a table summarizing terminal values and emission colors of the respective NAND gates shown in FIG. 7.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and the preferred embodiments according to the accompanying drawings.

FIG. 2 schematically illustrates the installation and interconnection relationship of a three-phase four-wire meter 10, a MOF 18, and a terminal box 14 incorporating a miswiring device according to an embodiment of the present invention. Wiring diagram. As shown in FIG. 2, ten wires 16 exiting the MOF 18 are input into the terminal box 14, and ten wires 12 from the terminal box 14 are three-phase, four-wire metering. It is input to the system 10. The external appearance of the terminal box 14 includes three LEDs indicating whether the voltage terminals P1, P2, and P3 are incorrectly wired, three LEDs indicating whether the current terminals 1S, 2S, and 3S are incorrectly wired, A total of eight LEDs 13 are exposed, including one LED indicating whether or not the phase terminals 1L, 2L, and 3L are incorrectly wired, and one LED indicating whether or not the common terminal P0 is incorrectly wired. .

FIG. 3 is a block diagram illustrating the inside of the terminal box 14 of FIG. As shown in FIG. 3, the power supply 100, the voltage detector 130, and the first LED 17 are connected in series to detect the voltage terminal, and the common terminal P0 is connected from the voltage detector 130. A P0 controller 150 for detecting a miswiring of a bay is provided, and an output thereof is connected to the first LED 170.

In order to detect the current terminal, the current detector 200, the comparator 220, and the second LED 240 are connected in series.

In order to detect the phase terminal, the phase detector 300, the microcomputer 320, and the third LED 340 are connected in series.

In addition, an alarm 400 that emits a warning sound is provided in the terminal box 14, and the alarm 400 includes a first LED 170, a second LED 240, and a third LED 340 connected in parallel. It is configured to be switched by the red light emitting signal.

FIG. 4 is a circuit diagram illustrating only P1 of the DC 12 volt power supplies 100 connected 1: 1 in each of the voltages P1, P2, and P3 in FIG. 3. As shown in FIG. 4, a transformer 101, a bridge circuit 103, an amplifier circuit 105, and a comparison circuit 107 that output 14 volts are connected in series to P1.

Both outputs of the transformer 101 are connected between two opposing contacts of the bridge circuit 103, respectively. The DC component of the bridge circuit 103 is amplified appropriately according to the ratio of the R value and the C value in the amplification circuit 105, thereby reducing the ripple. And a direct current 12 volts is output by the feedback action from the comparison circuit 107.

FIG. 5 is a circuit diagram of the voltage detector 130 connected in series with the power supply circuit 100 of FIG. 4. As shown in FIG. 5, the "+" input side of the comparator 131 is connected to a DC 12 volt, and is grounded through the zener diode 137 on the "-" side. In addition, 12-volt DC is connected to the "-" side through a resistor 135. The output terminal of the comparator 131 is connected in series with the base of the resistor 140 and the transistor 139. The emitter of transistor 139 is grounded, and the collector is connected to the input side of resistor 142 and NOT gate 133 respectively. The 12 volt DC power is supplied to the other end of the resistor 142, the NOT gate 133, and the comparator 131.

FIG. 6 is a circuit diagram common to the first LED 170, the second LED 240, and the third LED 340 of FIG. 3. The LEDs used in FIG. 6 are two parts 172 and 173 displayed on the circuit, but are actually one component capable of selectively emitting green and red light. This LED has three terminals, the second terminal of which is grounded through resistor 174. The NOT gate 171 is provided between the first terminal and the third terminal. Therefore, green light is emitted when the input side of the NOT gate 171 is "1", and red light is emitted when the output side of the NOT gate 171 is "1" when the input side of the NOT gate 171 is "0". .

FIG. 7 is a circuit diagram of the P0 controller 150 for detecting incorrect wiring of the common terminal PO of FIG. 3. As shown in FIG. 7, one side of the bridge circuit 151 has a capacitor C connected to each of the voltage terminals P1, P2, and P3 connected in parallel, and the other side facing the one side has a common terminal P0. Connected. A zener diode 155 and a resistor 156 are connected in series with the output side of the bridge circuit 151, and a resistor 152, a zener diode 153, and a capacitor 154 are connected between the output side and the zener diode 155. Are each connected in parallel. The base of transistor 157 is connected to resistor 156, the emitter is grounded, and the collector is connected to a direct current 12 volt power source via resistor R.

The first input of the first NAND gate 158 is connected to the miswiring signal 167 of each of the voltage terminals P1, P2, and P3 connected in parallel, and the second input is connected to the collector of the transistor 157. A first input and a second input of the second NAND gate 159 are connected with the first input of the first NAND gate. The first input and the second input of the third NAND gate 160 are connected to the second input of the first NAND gate. The fourth NAND gate 162 is connected to an output of the second NAND gate 159 and an output of the third NAND gate 160, respectively.

A resistor 163 and a diode 164 are connected in series between the output of the fourth NAND gate 162 and the output of the first NAND gate 158. The base of the transistor 165 is connected between the resistor 163 and the diode 164, the collector is connected to a direct current 12 volt power source via a resistor R, and the emitter is grounded. NOT gate 166 is connected to the emitter of transistor 165 as an input.

FIG. 8 is a circuit diagram illustrating one of the current detectors 200 connected 1: 1 in each current 1S, 2S, and 3S terminal of FIG. 3. As shown in FIG. 8, a current transformer CT is disposed between the current terminal 1S and the phase terminal 1L, and the output side of the current transformer CT is connected to the comparator 204 through a resistor 202. It is connected to the input side of "+". A grounded resistor 201 is connected between the output side of the current meter CT and the resistor 202. The capacitor 206 and the variable resistor 205 are connected in series between the "-" side of the comparator 204 and the ground.

9 is a circuit diagram of a comparator 220 connected in series to the current detector 200 of FIG. 8. As shown in FIG. 9, the first comparator 222 and the second comparator 227 are connected in series. The output of the first comparator 222 is connected to the "+" input side of the second comparator 227, and is connected in series with the resistor 236 and the capacitor 237 between the "-" input side of the second comparator and ground. . Diode 239 and resistor 238 are fed back in parallel from the output side of second comparator 227. Two diodes 228 and 229 and a resistor 234 are connected in series between the output side of the second comparator 227 and the base of the transistor 230. The resistor 232 and the capacitor 233 are connected in parallel between the contact of the diode 229 and the resistor 234 and the ground. The base of transistor 230 is connected to resistor 234, the emitter is grounded, and the collector is supplied with 12 volts DC. The collector of the transistor 230 is connected to the input side of the NOT gate 231.

FIG. 10 is a circuit diagram illustrating a phase detector of only P1-1S without the phase detectors for P2-2S and P3-3S among the phase detectors 300 of FIG. 3. As shown in FIG. 10, two resistors 304 and 306 are connected in series between the voltage terminal P1 and the common terminal P0. The converting means 302 is connected between the two resistors 304 and 306 as a detected sine wave as an input, and converts the input sine wave into a square wave.

A resistor 308 is connected between the output side (+) and the ground (-) of the current meter 1S of the current terminal 1S, and the output side (+) is connected to the input side of the same conversion means 302 to detect it. The inputted sinusoidal wave is input, and the inputted sinusoidal wave is converted into a square wave and output. These change means 302 are provided for each terminal P1, P2, P3, 1S, 2S, 3S, and each output is connected to the input side of the microcomputer 320, respectively.

The microcomputer inputs the embodied wave by the converting means 302, and determines whether the phase terminals are positively or incorrectly wired according to the input period of the embodied wave.

Hereinafter, a method of operating an incorrect wiring detection device for a three-phase four-wire meter according to the present invention will be described.

First, the operation principle of detecting whether P1 is positive or unwired among the voltage terminals P1, P2, and P3 will be described. As shown in FIG. 4, the voltage of P1 is converted into direct current through the transformer 101, the bridge circuit 103, the amplifier circuit 105, and the comparison circuit 107. The converted direct current is applied to the input of the circuit shown in FIG. When a predetermined DC 14 volt is normally input, the base of the transistor 139 is switched so that a current flows from the collector to the emitter, and the input of the NOT gate 133 becomes "0". Therefore, the output of the NOT gate 133 becomes "1".

If an abnormal current is input, it is compared by the comparator 131 to turn off the base of the transistor 139. Thus, current flows to ground through resistor 142 and NOT gate 133. As a result, the input side of the NOT gate 133 becomes "1" and the output becomes "0".

The output of FIG. 5 is applied to the input of the LED 170 shown in FIG. When the input is normal (“1”), the green light emission 172 is performed, and when the input is abnormal (“0”), the output side of the NOT gate 171 becomes “1”, thereby generating the red light 173. The circuits of FIGS. 4, 5, and 6 are connected in series with each other and are provided in a 1: 1 ratio for each voltage terminal P1, P2, and P3.

Hereinafter, an operation principle of detecting whether the common terminal P0 is connected or wired will be described. FIG. 11 is a table summarizing terminal values and emission colors of the respective NAND gates shown in FIG. 7. As shown in FIGS. 7 and 11, when the voltage terminals P1, P2, and P3 are miswired and turned off regardless of the common terminal P0, green light is emitted as shown in the LED of FIG. 11. This is for the miswiring of each voltage terminal P1, P2, P3 to be displayed separately in each first LED and not affecting the LED of P0. As shown in the second column of FIG. 11, the voltage terminals P1, P2, In the case of incorrect wiring such that any of the common terminals P0 is crossed and the common terminal P0, red light is emitted, and in the case of incorrect wiring such that only the common terminal P0 is shorted as in the third column, the red light is emitted. Is done.

Hereinafter, an operation principle of detecting whether the 1S is correct or wired among the current terminals 1S, 2S, and 3S will be described. As shown in FIG. 8, the current transformer CT outputs a DC component from the current flowing between the current terminal 1S and the phase terminal 1L and inputs it to the comparator 204. The comparator 204 compares the predetermined value and outputs the result. The output signal acts as an input of FIG. As shown in FIG. 9, when the input electric signal is normal while the first comparator 222 and the second comparator 227 connected in series are normal, the base of the transistor 230 is "1". Current through the collector. As a result, the input side of the NOT gate 231 becomes "0", and the output side becomes "1". If the wiring of the current terminal is miswired, the base of the transistor 230 becomes "0" so that DC 12 volts flows to the ground through the input side of the NOT gate 231. Therefore, the output of the NOT gate 231 becomes "0". The output of FIG. 9 is transmitted to the second LED 240 same as that of FIG. 6 to emit green light 172 for normal wiring and red light 173 for incorrect wiring. The circuits of FIGS. 8 and 9 are connected in series to each other and are provided in a 1: 1 ratio for each terminal 1S-1L, 2S-2L, and 3S-3L.

Hereinafter, an operation principle of detecting whether the phase terminals 1S, 2S, and 3S are connected or wired will be described with reference to FIG. 10. As shown in FIG. 10, a sinusoidal wave of a sinusoid may be detected at the resistance connection points 304 and 306 between P1 and P0. The detected sinusoidal wave curve is input to the converter 302, converted into a square wave embodied wave, and enters the P1 input side of the microcomputer 320. The sinusoidal wave measured by the current meter 309 from the current terminal 1S is input to the same but separately installed converter 302 and converted into a real wave in the same manner. The implementation wave thus converted enters the 1S input side of the microcomputer 320. In this manner, the implementation wave is input to each input side P1, P2, P3, 1S, 2S, and 3S of the microcomputer 320.

In case of normal wiring, sinusoidal wave is generated every 1/60 second and zero crossing of sinusoidal wave is done three times at 120 degree intervals. It has a value of approximately 5.555 ms. Therefore, when the pulse period of the input side exists in the range of about 5.5 to 5.6 kHz, the microcomputer 320 may be considered to generate a correct sine wave, which may be determined as a correct phase wiring. If the phase terminal is miswired, the period of the waveform has a range of 5.5 ~ 5.6Hz. Therefore, in this case, the microcomputer 320 determines that the phase terminal is miswired. The microcomputer 320 may be programmed by coding the above description and algorithm in a language such as assembly language.

If it is determined that incorrect wiring occurs in at least one of voltage terminal, current terminal, phase terminal, and common terminal, the corresponding LED is not only converted from green light to red light but also alarm 400 such as a buzzer sounds. B. The worker can easily determine whether or not noon wiring by hearing.

Therefore, according to the present invention as described above, there is an effect that can be easily recognized whether the ten wiring is miswired between the meter and the MOF installed in a stationary type. In addition, since each voltage terminal (P1, P2, P3), each current terminal (1S, 2S 3S), each phase terminal (1L, 2L, 3L) and the common terminal (P0) is detected and displayed independently There is an advantage that you can pinpoint the location of the wrong wiring.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims will cover such modifications and variations as fall within the spirit of the invention.

Claims (8)

Three-phase 4-wire meter with three voltage terminals (P1, P2, P3), three current terminals (1S, 2S, 33), three phase terminals (1L, 2L, 3L) and common terminal (P0) 10); And It has three voltage terminals (P1, P2, P3), three current terminals (1S, 2S, 33), three phase terminals (1L, 2L, 3L) and a common terminal (P0) and has three current transformers (CT1) inside. In the MOF 18 having the transformers PT1, PT2, PT3 corresponding to CT2, CT3 and the current transformers CT1, CT2, CT3, respectively, It is installed between the meter 10 and the MOF 18, it is determined whether each voltage terminal of the MOF 18 is connected to correspond to each voltage terminal of the meter 10, and the MOF ( It is determined whether each current terminal of 18) is connected to correspond to each current terminal of the meter 10, and each phase terminal of the MOF 18 corresponds to each phase terminal of the meter 10, respectively. Judging and display means (14) for determining whether or not to be connected correctly, and whether the common terminal of the MOF (18) is connected to the common terminal of the meter (10) to display whether the wiring is correct or incorrect; Mis-wiring detection device of a three-phase four-wire meter. The method of claim 1, wherein the determination and display means 14, Voltage detector means (130) connected to the MOF (18) to determine whether the voltage terminals (P1, P2, P3) are positive or incorrect; A P0 controller (150) comprising a plurality of NAND gate combinations for determining whether the common terminal (P0) is right or wrong; A first LED 170 displaying the determination result of the detector means 130 and the determination result of the P0 controller 150, respectively; Current detector means (200) connected to the MOF (18) to determine whether the respective current terminals (1S, 2S, 33) are positive or incorrect; Comparator means (220) connected in series with the current detector means (200) for amplifying and comparing the signal from the current detector means (200); Second LEDs 240 respectively displaying the determination results of the comparator means 220; Conversion means (302) for detecting a sine wave from each of the voltage terminals (P1, P2, P3) and the current terminals (1S, 2S, 33) and converting the sine wave into a real wave; A microcomputer (320) for inputting the embodied wave by the converting means (302) to determine whether the phase terminals are correctly or misaligned according to an input period of the embodied wave; And And a third LED (340) for displaying the determination result of the microcomputer (320). The method of claim 2, wherein the power supply 100 is further provided between the MOF 180 and the voltage detector means 130, the power supply 100, A transformer 101 connected to the voltage terminals P1 and PO; A bridge circuit 103 connected in series with the transformer 101; An amplifier circuit 105 connected in series with the bridge circuit 103; And And a comparison circuit (107) connected in series with the amplification circuit (105). The method of claim 2 or 3, wherein the voltage detector means 130 is provided for each of the voltage terminals (P1, P2, P3), the detector means 130, A comparator 131 to which the voltage is input at the "+" side and a zener diode 137 is connected to the "-" side; A resistor 140 having one end connected in series with an output terminal of the comparator 131; And A transistor connected to the other end of the resistor 140, an emitter grounded, and a collector connected to the input side of the resistor 142 and the NOT gate 133, respectively; Incorrect wiring detection device of a three-phase four-wire weighing system comprising a. The method of claim 2, wherein the P0 controller 150, A bridge circuit 151 having one side connected in parallel with each of the voltage terminals P1, P2, and P3, and the other side connected with the common terminal P0; A zener diode 155 and a resistor 156 connected in series with the bridge circuit 151; A transistor 157 having a base connected to the resistor 156, an emitter grounded, and a collector connected to a DC power source through a resistor R; A first NAND gate 158 having a first input signal connected to the collector of the transistor 157 and a second wiring signal 167 of each of the voltage terminals P1, P2 and P3 connected in parallel; A second NAND gate 159, wherein a first input and a second input are connected with a first input of the first NAND gate; A third NAND gate 160 connected with a first input and a second input to a second input of the first NAND gate; A fourth NAND gate 162 having an output of the second NAND gate 159 and an output of the third NAND gate 160 as inputs, respectively; A resistor 163 and a diode 164 connected in series between the output of the fourth NAND gate 162 and the output of the first NAND gate 158; A transistor (165) having a base connected between the resistor (163) and the diode (164), a collector connected to a DC power supply through a resistor (R), and an emitter grounded; And And a NOT gate (166) for inputting the emitter of the transistor (165). The method of claim 2, wherein the first LED 170, the second LED 240 and the third LED 340, respectively, LEDs 172 and 173 having the second terminal grounded through a resistor 174; And NOT gate 171 connected between the first terminal and the third terminal of the LED (172, 173); green light emission 172 when the normal wiring, red light emission (173) when incorrect wiring A miswiring detector for a three-phase, four-wire meter. According to claim 6, The third terminal of each of the first LED 170, the second LED 240 and the third LED 340 is connected in parallel to be connected to switch the alarm 400, Three-phase four-wire weighing meter, characterized in that the alarm 400 generates a warning sound when any one of the first LED 170, the second LED 240 or the third LED 340 is emitting red light. Incorrect wiring detection device. 3. The microcomputer 320 of claim 2, wherein the microcomputer 320 is programmed to determine that it is normal when the input period of the embodied wave is in the range of 5.5 to 5.6 ms, and to determine that it is a miswiring when the period is outside the range. Incorrect wiring detection device for 4-phase 4-meter meter.