JP6517610B2 - Voltage checker - Google Patents

Description

  The present invention relates to a voltage checker for checking a voltage applied to a wire, and more particularly to a voltage checker for checking if it is 100V / 200V.

  After installation and construction of the residential distribution panel, an electrician will conduct a voluntary check or a connection check such as a completion inspection will be conducted. One of the connection confirmation items is voltage confirmation of the branch circuit in a live state. This is a confirmation of 100V / 200V. If there is a misconnection at the time of construction, 100V is applied to the circuit to be supplied 200V and the load does not operate normally or 200V is applied to the circuit to be supplied 100V. This is done to prevent this, as the load may lead to an accident such as burnout.

In this voltage confirmation method, conventionally, since a probe such as a voltage tester is brought into contact with the conductive portion of the branch breaker for measurement, sufficient care has to be taken to prevent a short circuit accident or the like due to the probe. Therefore, a non-contact voltage measurement method which enables safe confirmation has been proposed.
For example, in Patent Document 1, a conductor is provided around two electric wires to be measured, a current flowing between the conductors is detected, and a voltage value is calculated using a coefficient obtained in advance to obtain a line voltage. The
Further, in Patent Document 2, a voltage generated between the electrodes when the cable is clamped by two probes provided with an inner electrode and an outer electrode and the same potential is set when an alternating voltage is applied between the outer electrodes of the probes Was measured to determine the voltage of the cable.

  On the other hand, the branch wires to be checked are the wires connected to the load side terminals of the branch breakers, and since the branch breakers are arranged in multiple rows in the distribution board, the branch wires of adjacent branch breakers are also connected. It exists near. When checking the branch wiring of the electricity distribution panel with which the thin breaker was assembled | attached especially as shown to patent document 3, the wiring of an adjacent branch breaker was close and was not easy.

JP 2002-55126 A Patent No. 4611774 gazette JP, 2008-47362, A

  Although the technique of Patent Document 1 does not limit the measurement object, the procedure is complicated because the voltage and impedance must be obtained in advance by measuring the voltage directly at the connection terminal. Further, since the technique of Patent Document 2 uses a ring-shaped probe for clamping a cable, an error is easily generated due to a gap generated with the attached cable. In addition, an error occurs due to the coating thickness of the cable to be measured.

On the other hand, when looking at a household distribution board, VVF cables are usually used for individual branch lines from the distribution board to lights and air conditioners. Therefore, for example, if a display unit or the like is set specifically for the VVF cable, it can be compatible with many home distribution boards without setting the coefficient each time. Further, since the material and thickness of the covering portion covering the core wire do not change significantly, it is possible to reduce the occurrence of an error.
Furthermore, in a distribution board on which a thin breaker as described in Patent Document 3 is assembled, the branch wires are arranged in the vertical direction of the branch breaker (in the depth direction of the distribution board). If a measuring jig in which a sensor to be detected is arranged is manufactured, it is conceivable that the line voltage can be measured smoothly even at a place where the wires are densely arranged.

  Therefore, in view of such problems, the present invention eliminates the need to set the coefficient each time by limiting the branch wires to be measured to a specific cable, and further specializes in the load side wiring of a specific branch breaker. An object of the present invention is to provide a voltage checker that can measure the voltage between wires of a wire with high accuracy by a simple operation by using a sensor device in which the distance between branch wires is limited.

In order to solve the said subject, the voltage checker which concerns on invention of Claim 1 contacts each of the coated electric wire, in order to measure the line voltage of a pair of electric wire connected to the load side terminal of a branch breaker. A sensor device having a plurality of electrodes to be driven and a voltage display unit for displaying voltage information proportional to a voltage generated between two electrodes in contact with the electric wire, the sensor device being formed in a plate shape, A plurality of electrodes are provided on one side, and the other side is covered with an electrode for a shield.
According to this configuration, since the back surface of the sensor device is shielded, when checking the voltage of the wire, even if the wire connected to the adjacent breaker is immediately behind the sensor device, the influence of the wire is It can be eliminated, and the voltage between lines can be measured accurately. And since information on line voltage is obtained by bringing the electrode into contact with the coated electric wire, it is possible to obtain it by a simple operation and to carry out stable measurement.

The invention according to claim 2 is that, in the configuration according to claim 1, the sensor device has three electrodes arranged side by side, and a central electrode and one electrode arranged at an end are connected via a capacitor, The electrode disposed at the end of the and the central electrode are electrically integrated.
According to this configuration, when the sensor device includes three electrodes, the load-side terminal of the branch breaker includes three terminals of a voltage pole, a neutral pole, and a voltage pole, and the electric wire is connected to two of them. It is convenient to check the line voltage of the configuration. Then, the voltage of the load wiring of the branch breaker connected to the single-phase three-wire type electric path can be checked with a simple circuit configuration in which the pair of electrodes are simply connected to each other.

  According to the present invention, since the back surface of the sensor device is shielded, when checking the voltage of the wire, even if the wire connected to the adjacent breaker is immediately behind the sensor device, the influence of the wire is It can be eliminated, and the voltage between lines can be measured accurately. And since information on line voltage is obtained by bringing the electrode into contact with the coated electric wire, it is possible to obtain it by a simple operation and to carry out stable measurement.

It is structure explanatory drawing which shows an example of the voltage checker which concerns on this invention. FIG. 3 is an open circuit diagram schematically showing an electrical configuration of a voltage checker. It is explanatory drawing which shows the sensor apparatus in measurement of the voltage of the electric wire connected to the load side terminal of a branch breaker, and is the figure seen from the left surface direction of a branch breaker. It is the figure which looked at the right side surface direction of the branch breaker which looked at the state of FIG. 3 from the other side. It is the figure which looked at the state of FIG. 3 from the top. It is a circuit diagram for demonstrating the electric current which flows into the shield electrode provided in the sensor apparatus. It is a circuit diagram which shows the flow of the current at the time of not providing a shield electrode in a sensor apparatus. It is explanatory drawing of the sensor apparatus which measures the line voltage of the electric wire connected to the terminal different from FIG. FIG. 6 is an explanatory view of a sensor device for measuring the line voltage of a wire connected to a terminal different from that of FIG. 3, in which (a) is a view from the left side of the branch breaker, (b) is the right side of the branch breaker It is the figure seen from the direction. It is a circuit diagram for demonstrating the electric current which flows into the shield electrode provided in the sensor apparatus in the measurement state of FIG.

  Hereinafter, embodiments embodying the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an example of a voltage checker according to the present invention, wherein the voltage checker comprises a sensor device 1 comprising three electrodes P (first electrode P1, second electrode P2, third electrode P3), and a voltage It has the main body 2 provided with the display part 2a. The sensor device 1 includes an electrode (shield electrode) S for shielding on the back surface, assuming that the surface provided with the three electrodes P is the front surface. And 3 is a wire to be measured, and the voltage is checked by bringing two of the three electrodes P into contact with the coated wire 3.

The branch wire to be checked is assumed to be the inner wire of VVF cable (Vinyl insulated vinyl sheathed flat-type cable), and the wire covered with the vinyl insulator is accommodated inside the vinyl sheath which is the outer jacket. . Then, when connecting to the branch breaker, the vinyl sheath is removed, and the vinyl insulator is removed only at the connecting end of the electric wire to connect the inner core wire.
The voltage measurement of such a VVF cable is performed by bringing the electrode P of the sensor device 1 into contact with the electric wire 3 whose core wire is covered with a vinyl insulator only by peeling the vinyl sheath.

FIG. 2 schematically shows the electrical configuration of the voltage checker. The internal capacitor Cm is disposed between the first electrode P1 and the second electrode P2 in the main body 2, and the voltage display unit 2a generates a voltage (between the first electrode P1 and the second electrode P2) generated in the internal capacitor Cm. The value proportional to the voltage of The second electrode P2 and the third electrode P3 are connected to each other inside the sensor device 1.
Hereinafter, the electric wire 3 in contact with the first electrode P1 will be described as a first electric wire, and the electric wire 3 in contact with the second electrode will be described as a second electric wire.

Between the first electrode P1 and the first electric wire, there is a capacitive coupling capacitance Cp1 (first capacity) generated by the covering covering the core of the first electric wire, and between the second electrode P2 and the second electric wire 3 There is also an electrostatic coupling capacitance Cp2 (second capacitance) generated by a coating that covers the core wire of the second electric wire. Therefore, it can be considered that the circuit shown in FIG. 2 is configured. In FIG. 2, Vc is a voltage between wires, V1 is a voltage generated in the first capacitor Cp1, V2 is a voltage generated in the second capacitor Cp2, and Vm is a voltage generated in the internal capacitor Cm.
The first capacitance Cp1 and the second capacitance Cp2 are VVF cables having the same characteristics, and therefore, can be processed with the same value.

From the circuit shown in FIG. 2, the line voltage Vc can be obtained as follows. Between the line voltage Vc, the voltage V1 generated in the first capacitance Cp1, the voltage V2 generated in the second capacitance Cp2, and the voltage Vm generated in the internal capacitor Cm,
Vc = V1 + Vm + V2
Relationship.

On the other hand, since the first capacitance Cp1 and the second capacitance Cp2 are connected in series, the combined capacitance Cvvf is
Cvvf = (Cp1 × Cp2) / (Cp1 + Cp2) (1)
It becomes. The voltage Vm generated in the internal capacitor Cm (electrostatic capacitance is also Cm) using this combined capacitance Cvvf can be expressed as follows:
Vm = {Cvvf / (Cvvf + Cm)} × Vc (2)
It becomes. From this equation, the voltage Vc is
Vc = Vm / {Cvvf / (Cvvf + Cm)} (3)
It can be seen that the line voltage Vc is proportional to the voltage Vm generated in the internal capacitor Cm. Further, since the combined capacitances Cvvf and Cm are fixed values, the line voltage Vc can be obtained if the voltage Vm can be measured.

  As a result, voltage information in proportion to the voltage Vm generated in the internal capacitor Cm is displayed in the voltage display unit 2a, and a coefficient specific to the VVF cable is obtained based on the combined capacitance Cvvf and the numerical value of the internal capacitor Cm. As shown in the voltage display section 2a of 1, the display of 100 V / 200 V can be implemented as the line voltage from the measured value of the voltage Vm.

  Thus, just by bringing the electrodes into contact with the coated electric wire 3, the information of the line voltage Vc can be obtained without bringing the electrode P into direct contact with the core wire, and the information of the line voltage Vc can be obtained by a simple operation. . Then, by using a preset coefficient, a value with high accuracy can be displayed on the voltage display unit 2a. Further, by making the measurement in contact with the coating of the electric wire 3, no variation occurs in the distance between the inner core wire and the electrode P, so the electrostatic coupling capacitance also becomes constant, and the occurrence of measurement error can be eliminated.

  As can be seen from the equation (2), the voltage generated in the internal capacitor Cm has nothing to do with the capacitance of the internal capacitor Cm, so the generated voltage (corresponding to Vm) in the open state without the capacitor attached You may measure it.

3 to 5 show a state in which the voltage of the electric wire 3 connected to the load-side terminal 5b of the branch breaker 5 is checked, and FIG. 3 shows a view from the left side of the branch breaker 5 The hand M of the operator who is operating is indicated by a two-dot chain line. 4 is a view of the state of FIG. 3 as viewed from the right side, and FIG. 5 is a view of the same as viewed from above.
Note that FIG. 5 shows a state in which three branch breakers 5 are adjacent to each other, and 5f indicates a branch breaker to be measured, and a branch breaker that affects measurement by being adjacent to 5g as described later. In practice, a large number of branch breakers 5 are arranged in such a dense state. Further, the branch breaker 5 shown here is a so-called thin breaker in which the power supply side terminal 5a and the load side terminal 5b are vertically arranged, and by using such a branch breaker 5, the electric wire 3 to be measured is also Arranged vertically. Therefore, three electrodes P of the sensor device 1 are used side by side in the same plane.

Specifically, as shown in FIGS. 3 and 4, the sensor device 1 is formed in a rectangular plate shape, three electrodes P are disposed on one surface, and the shield electrode S is formed on the entire surface on the other surface. ing. The three electrodes P are arranged at intervals of the load side terminals 5b of the branch breaker 5, and are arranged at the same interval in the vertical direction.
Moreover, although the load side terminal 5b of the branch breaker 5 is provided with three terminals, two of them are used and the electric wire 3 is connected. The three terminals are arranged, for example, from the top to the voltage pole L1, the neutral pole N, and the voltage pole L2, and when the neutral pole N and any one upper and lower voltage pole are used, the line voltage is 100 V If two voltage poles L1 and L2 are used, the line voltage is 200V.

FIG. 6 is an explanatory view showing the flow of the current of the sensor device 1 at this time, 10 is a commercial power source, F1 is the end of the branch electric wire 3 of the branch breaker 5 (branch breaker 5f shown in FIG. The connected load, F2 represents the load connected to the adjacent branch breaker 5 (branch breaker 5g shown in FIG. 5), and W represents the impedance of the human body grounded via the hand M of the worker.
As shown in FIG. 5, when the electric wire 3 to be measured and the adjacent electric wire 3 are close to each other, the sensor device 1 is inserted between the electric wire 3 and the electric wire 3 and brought into contact with the electric wire 3 to be measured At this time, electrostatic coupling capacitances Cp3 and Cp4 are formed and influenced even with the electric wire 3 connected to the adjacent branch breaker 5g.
However, as shown in FIG. 6, by providing the shield electrode S, the current related to the electrostatic coupling capacitances Cp3 and Cp4 passes through the hand of the operator holding the sensor device 1 and escapes to the ground. Therefore, the voltage generated between the electrodes P is not affected.

  FIG. 7 is a view for comparison with FIG. 6 and shows the flow of current when the sensor device 1 without the shield electrode S is used. As shown in FIG. 7, the inserted sensor device 1 is connected to the first electrode P1 and the second electrode P1 via electrostatic coupling capacitances Cp3 and Cp4 formed between the wire 3 connected to the adjacent branch breaker 5g. It can be seen that the measured value is affected because the current flows between the electrodes P2.

  FIG. 8 shows a state in which the voltage between the wires 3 connected to the load side terminal 5b different from that in FIG. 3 is measured. When measuring the voltage of the electric wire 3 connected between the central N pole and the lower voltage pole L2, as shown in FIG. 8, the same electrode P as in FIG. 3 (first electrode P1 and second electrode It can be measured using P2). Therefore, also in this case, the circuit shown in FIG. 6 is formed, and the shield electrode S is grounded via the operator and can be favorably measured.

FIG. 9 is further different and shows the measurement by the sensor device 1 when the electric wire 3 is connected to the two voltage poles L1 and L2, (a) is a view of the branch breaker viewed from the left side direction, (b) is a branch It is the figure which looked at the breaker from the right side direction. In this case, measurement is performed using the first electrode P1 and the third electrode P3.
FIG. 10 is an explanatory view showing the flow of current of the sensor device 1 at this time, and F3 is a load connected to the end of the branch electric wire 3 of the branch breaker 5 to be measured (branch breaker 5f shown in FIG. 5) F4 shows the load connected to the tip of the branch electric wire 3 of the adjacent branch breaker 5 (branch breaker 5g shown in FIG. 5). The same components as those in FIG. 6 are denoted by the same reference numerals.
Also in this case, capacitive coupling capacitances Cp3 and Cp6 are generated between the wire 3 connected to the adjacent branch breaker 5g as shown in FIG. 10, but they escape from the shield electrode S to the ground through the operator. The voltage generated between the wires 3 to be measured can be measured accurately.

As described above, since the back surface of the sensor device 1 is covered with the shield electrode S, when the voltage of the wire 3 is checked, the wire 3 connected to the adjacent branch breaker 5 (5 g) Even on the back side, the influence of the electric wire 3 can be eliminated, and the line voltage can be measured accurately. And since information on line voltage is obtained by bringing the electrode P into contact with the coated electric wire 3, it can be obtained by a simple operation and stable measurement can be carried out.
Further, since the three electrodes P of the sensor device 1 are arranged side by side on the same plane, the load side terminals 5b of the branch breaker 5 are arranged in the order of the voltage pole L1, the neutral pole N and the voltage pole L2, It is convenient to check the line voltage of the configuration in which the wire 3 is connected to the two terminals. Then, the voltage of the load wiring of the branch breaker connected to the single-phase three-wire circuit can be checked with a simple circuit configuration.

  1 ·· Sensor device 2 ·· Main body 2a ·· Voltage display unit 3 ·· Wires 5 ··· Branch breaker, Cm ··· Internal capacitor, P ·· electrode, S ··· Shield electrode.

Claims (2)

A sensor device comprising a plurality of electrodes which are brought into contact with each of the coated wires in order to measure the line voltage of a pair of wires connected to the load side terminal of the branch breaker;
A voltage display unit for displaying voltage information proportional to a voltage generated between two electrodes brought into contact with the electric wire;
A voltage checker characterized in that the sensor device is formed in a plate shape, the plurality of electrodes are provided on one surface, and the other surface is covered with an electrode for a shield.   In the sensor device, the three electrodes are arranged side by side, and the central electrode and one of the electrodes disposed at the end are connected via a capacitor, and the electrode disposed at the other end and the central electrode are The voltage checker according to claim 1, wherein the voltage checker is electrically integrated.

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