JP2014025707A - Current measuring member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a current measuring member that eliminates complicated wiring work when installing current measuring means that detects a current value flowing to a load arranged inside a housing.SOLUTION: A current measuring member measures a current flowing in a cable way to feed power to electrical equipment accommodated inside a housing or in a cable way inside the electrical equipment accommodated inside the housing. An electric current sensor is configured with a pair of arm parts projected from one end of a substrate, and an inside thereof serves as a wiring insertion part having open ends. Each of the pair of arm parts has a magnetic detection element arranged therein. The electric current sensor is mounted onto the cable way so that the current is measured. The electric current sensor is retained inside a case covering the substrate. A contact part that contacts the cable way is formed as power supply means for the electric current sensor inside the case.

Description

  The present invention relates to a current measuring member including means for detecting a current value flowing to a load in a power distribution device such as a distribution board or a breaker.

  The current supply to the load is usually performed via a distribution board arranged in the same electric equipment storage box. In the distribution board, a number of branch breakers are connected to three power supply bars connected to the secondary side of the main breaker, and the secondary side of each branch breaker is connected to a load circuit.

  When it is desired to measure the load current, it is common to detect the value of the current flowing to the load by attaching a current transformer (CT) to each branch breaker. For example, as shown in Patent Document 1, conventionally, A current transformer was arranged on the secondary side of each branch breaker.

  However, in order to place each CT on the secondary side of the branch breaker, it is necessary for the customer to pass the wiring through the CT, and there is a problem that it takes time to connect the load to the load through the wiring one by one. It was. In addition, when such a CT is used, the size of the distribution board is increased because of the large size. However, in the case of CT, if it is attempted to reduce the size, the number of windings of the coil formed inside the CT cannot be ensured, so that it is very difficult to reduce the size.

  On the other hand, as a current measuring means, a technique using a Hall element instead of the CT is also known (for example, Patent Document 2). The current measuring means using the Hall element is for detecting a magnetic field generated by the current. On the substrate constituting the current measuring means using the Hall element, in addition to the magnetic detection element for detecting the magnetic field, the magnetic detection element An integrated circuit for processing current output data to calculate a current value is mounted. Since this integrated circuit receives the supply of DC power from the outside and performs the above-described calculation processing, when a Hall element is used as the current measuring means, a power supply means to the Hall element is required. . However, when power is supplied by separately wiring a power supply line dedicated to the Hall element, there is a problem that the wiring work becomes complicated.

Japanese Patent Laid-Open No. 06-165320 Noto 3142092

  An object of the present invention is to solve the above-described conventional problems and to provide a current measuring member that does not require complicated wiring work when installing a current measuring means for detecting a current value of an electric device.

  The current measuring member of the present invention made to solve the above problems is a measurement of a current flowing in an electric circuit for supplying power to an electric device housed in the housing or an electric circuit inside the electric device housed in the housing. The current measurement member is configured to measure the current by projecting a pair of arm portions from one end of the substrate and using the inner side as a wiring insertion portion with the end portions opened, and applying a magnetism to each of the pair of arm portions. A current sensor having a structure in which a detection element is arranged is attached to an electric circuit, and the current sensor is held in a case that covers the substrate, and serves as a power supply means to the current sensor in the case, and a contact portion that contacts the electric circuit Is formed.

  According to a second aspect of the present invention, in the current measuring member according to the first aspect, a plug terminal portion that can be elastically inserted into the electric path is provided between the arm portions of the current sensor, and a contact portion is formed in the plug terminal portion. It is characterized by this.

  According to a third aspect of the present invention, in the current measuring member according to the first or second aspect of the present invention, the case includes a power supply unit incorporating a rectifying means.

  According to a fourth aspect of the present invention, in the current measuring member according to the second or third aspect, the case includes a plurality of cases each holding a current sensor, and each case is mounted on an electric circuit of a different phase and formed in one case. The power source of the current sensor is supplied by a contact portion formed in one case and a contact portion formed in the other case. According to a fifth aspect of the present invention, in the current measuring member according to the fourth aspect, a voltage detection circuit for detecting a voltage from a contact portion formed in one case and a contact portion formed in the other case is formed. It is what.

  The current measuring member of the present invention is a current measuring member that measures the current flowing in the electric circuit that feeds power to the electric device housed in the housing, or the electric circuit inside the electric device housed in the housing, The current is measured by a pair of arms projecting from one end of the substrate and the inside thereof being used as a wire insertion part having an open end, and a magnetic sensor is arranged on each of the pair of arms. The current sensor is held in a case that covers the substrate, and as a power supply means to the current sensor in the case, a contact portion that contacts the electric circuit is formed. It is possible to supply power to the current sensor in the case from the electric circuit equipped with the current sensor, and there is no need to separately supply a power supply line dedicated to the current sensor. And, it is possible to eliminate the need for complicated wiring work.

  According to the second aspect of the present invention, the plug terminal portion is provided between the arm portions of the current sensor so that the plug terminal portion can be elastically inserted into the electric path, and the contact portion is formed on the plug terminal portion. The electric circuit can be formed between the electric circuit and the current sensor by a simple operation of inserting the elastically. The power supply to the current sensor needs to be performed with a direct current, but when the current flowing through the electric circuit is an alternating current, a power supply unit composed of a rectifier or the like is built in the case as in the invention of claim 3. Thus, when the current flowing through the electric circuit is an alternating current, it is possible to perform AC / DC conversion in the case to supply power to the current sensor.

  According to the invention of claim 4, there are a plurality of cases holding current sensors, each case is mounted on a different phase electric circuit, and the power source of the current sensor formed in one case is connected to one case. By supplying the contact portion formed and the contact portion formed on the other case, power can be supplied to the current sensor only by a simple operation of elastically inserting the plug terminal portion into the electric circuit. It becomes possible to measure the current. According to the invention of claim 5, the voltage between the phases is measured by forming the voltage detection circuit for detecting the voltage from the contact portion formed in one case and the contact portion formed in the other case. Therefore, it is possible to measure the power together with the current measured by the current sensor.

It is a front view of the plug-in distribution board arrange | positioned in the electric equipment storage box. It is a front view of the plug-in distribution board arrange | positioned in the electric equipment storage box. It is a perspective view of a current sensor. It is a figure explaining the flow of the electric current detection by a current sensor. It is explanatory drawing of the case which accommodates a current sensor. 2 is a front view of a case according to Embodiment 1. FIG. 6 is a front view of a case of Embodiment 2. FIG. It is a front view of the case of Embodiment 3. It is a front view of the case of Embodiment 4. It is a perspective view which shows the alternative current sensor attachment structure in Embodiment 3,4. 10 is a front view of a case of Embodiment 5. FIG.

  Preferred embodiments of the present invention are shown below.

  The current measuring member according to the present invention is configured to measure a current flowing to an electric device by projecting a pair of arm portions from one end of the substrate and using a wiring insertion portion having an open end on the inside, and a pair of arm portions Each of which includes a current sensor having a structure in which a magnetic detection element is arranged. FIG. 1 shows an example in which a bus bar 1 is used as an electric circuit, 3 is a main breaker, 1 is three bus bars connected to the secondary side of the bus bar 1 via a lead bar 4, and 5 is both sides of the bus bar 1 There are a number of branch breakers arranged in These are housed in an electrical equipment storage box (not shown) to form a plug-in distribution board.

  In the present embodiment, the current sensor 2 is arranged in the electric circuit that supplies power from each bus bar 1 serving as an electric circuit to the branch breaker 5, but the arrangement position of the current sensor 2 is an electric circuit that supplies power to the electrical equipment. Any configuration may be used. For example, as shown in FIG.

  As shown in FIG. 3, the current sensor 2 has a substantially U-shaped structure in which one end of a substrate 6 is opened to form a pair of arm portions 7, and a magnetic detection element 8 is mounted on the pair of arm portions. doing. Further, a portion formed by opening one end of the substrate 6 is a wiring insertion portion 7a through which the bus bar 1 serving as an electric path is inserted.

  As shown in FIG. 4, the magnetic detection element 8 mounted on the current sensor 2 detects a magnetic field generated by a current flowing through the electric path 13 disposed in the wiring insertion portion 7 a between the arm portions 7. In addition, an integrated circuit 10 for processing the detection output of these magnetic detection elements 8 and calculating the value of the current flowing in the electric circuit 13 is also mounted. In the present embodiment, one magnetic detection element 8 is mounted on each arm portion 7, but a plurality of magnetic detection elements 8 may be mounted. By mounting a plurality, it is possible to investigate the current flowing through the electric circuit 13 more accurately. Moreover, since such a current sensor 2 can measure without contact with the electric circuit, it can be measured without being affected by heat from the electric circuit 13 or the like.

  As described above, by using the substrate-shaped current sensor, it is possible to greatly reduce the arrangement space of the current sensor as compared with the case where the conventional core-shaped current sensor is used. In addition, in the conventional core-shaped current sensor, when installing the current sensor, it is necessary to pass wiring through the core-shaped current sensor. When CT is installed after the distribution board is installed, all branch breakers must be installed. However, the current sensor 2 used in the present invention has one end of the substrate 6 open. Therefore, even when various wirings are made after the distribution board is installed, the assembling work can be easily performed.

  In the present invention, the current sensor 2 is used in a state of being entirely covered with a case 9 shown in FIG.

  As shown in FIG. 5, the case 9 is formed in a substantially U-shaped structure having a pair of case arm portions 11, similarly to the current sensor 2, and the electric path 13 is connected to the wiring insertion portion 7 a between the case arm portions 11. Is provided with a plug terminal portion 12 that can be elastically inserted.

  Here, if the positional relationship between the electric path 13 and the magnetic detection element 8 is deviated, the current detection error is affected. Therefore, it is preferable that the current sensor 2 be arranged so as not to cause backlash. In the present embodiment, a guide inclined portion is formed in the plug terminal portion 12 so that the electric path 13 is inserted into a desired fixed position (near the center line of the current sensor 2) with respect to the current sensor 2. Moreover, it is preferable to hold | maintain the current sensor 2 without generating shakiness by providing the inside of the plug terminal part 12 with a current sensor latching means.

  It is necessary to supply DC power to the current sensor 2. In the present invention, the contact portion 14 that contacts at least two of the electrical paths 13 is formed in the case 9, so that power can be supplied directly from the electrical path 13 to the current sensor 2 in the case 9. According to this configuration, it is not necessary to separately supply a power supply line dedicated to the current sensor 2 and perform power supply, so that complicated wiring work can be eliminated when installing the current measuring means.

  Hereinafter, as Embodiments 1 to 4, the case 9 in which the contact portion 14 that contacts at least two of the electric paths 13 is formed will be described in detail.

(Embodiment 1 shown in FIG. 6)
Two lead wires 15 are led out from the case 9 of the present embodiment, and a contact portion 14 is formed at the tip thereof. By bringing the contact portion 14 into contact with the two electric paths 13, power can be supplied from the electric path 13 to the current sensor 2 in the case 9.

  Although it is necessary to supply power to the current sensor 2 with a direct current, if the current flowing through the electric circuit 13 is an alternating current, a power supply unit (not shown) with a built-in rectifier should be built in the case 9. Thus, the power supply from the attached electric circuit 13 can be AC / DC converted by the power supply unit in the case 9 to supply power.

(Embodiment 2 shown in FIG. 7)
From the case 9 of the present embodiment, one lead wire 15 is led out, and a contact portion 14 is formed at the tip thereof. The other contact portion 14 is formed on the arm portion 11 of the case and has a structure in contact with the electric path 13 inserted into the plug terminal portion 12. Therefore, according to the present embodiment, with respect to the contact portion 14 formed on the arm portion 11 of the case, the wiring sensor 13 is not subjected to any wiring work, and at the same time as the work of arranging the current sensor 2 on the electric circuit 13 that is the current measurement target. The electric circuit formation for the current sensor 2 can be completed. In this embodiment as well, it is desirable to form a power supply unit in the case 9.

(Embodiment 3 shown in FIG. 8)
The present embodiment is a modification of the second embodiment, and instead of the lead wire 15 of the second embodiment and the contact portion 14 formed at the tip thereof, a power supply case 16 is accommodated in the current sensor 2. It is arranged adjacent to the case 9. Both cases 16 and 9 are connected by electric wires 17a and 17b.

  Similar to the case 9 housing the current sensor 2, the power supply case 16 is formed in a substantially U-shaped structure having a pair of case arm portions 11, and the electric path 13 is elastically provided between the case arm portions 11. A plug terminal portion 12 that can be inserted is provided. Similarly to the case 9, a contact portion 14 is formed on the arm portion 11 of the case, and has a structure in contact with the electric path 13 inserted into the plug terminal portion 12. The power supply case 16 houses not the current sensor but the power supply unit 18 including a rectifier serving as a rectifier.

  In the second embodiment, the contact portion 14 formed at the tip of the lead wire 15 needs to be wired with the electric path 13, but according to the present embodiment, any one of the two contact portions 14 With regard to, the electric circuit formation for the current sensor 2 can be completed simply by inserting the electric circuit 13 into the plug terminal portion 12.

  In the present embodiment, the power acquired through the contact portion 14 formed in the case 9 housing the current sensor 2 is first sent to the power supply case 16 via the electric wire 17 a and input to the power source 18. The On the other hand, the power acquired through the contact portion 14 formed on the power supply case 16 is also input to the power source 18 through the electric wire 18a. Then, power is supplied from the power supply unit 18 to the current sensor 2 via the electric wire 17b. Further, if the attached electric circuit 13 is an alternating current, it is AC / DC converted by the rectifier of the power supply unit 18, and the direct current power is sent to the case 9 containing the current sensor 2 via the electric wire 17 b and supplied to the current sensor 2. Supplied. The current measured by the current sensor 2 is output from the electric wire 17c.

(Embodiment 4 shown in FIG. 9)
The present embodiment is a modification of the above-described second and third embodiments, in which the current sensor 2 and the power supply unit 18 are accommodated in both adjacent cases, and the current sensor 2 accommodated in the opposite case is mutually connected. On the other hand, DC power can be supplied. Although the case 9 and the power supply case 16 in the third and fourth embodiments are each described as one, a plurality of cases 9 accommodating the current sensor 2 are prepared, and the power supply unit 18 of the power supply case 16 is prepared. The power may be supplied to the case 9 containing the plurality of current sensors 2.

(Alternative structure of Embodiment 3 and Embodiment 4 shown in FIG. 10)
In the structure shown in the third and fourth embodiments, it has been described that it is connected to the bus bar 1 serving as the electric circuit of the distribution board. However, as shown in FIG. 10, the electric circuit formed inside the branch breaker 5 It may be arranged so as to straddle a twisted line (not shown). In that case, the current sensor insertion portion 5a is formed in the branch breaker 5, the current sensor 2 is inserted, and the case 9 containing the current sensor 2 or the power supply case 16 is inserted so as to straddle the stranded wire. It is something to be made.

(Embodiment 5 shown in FIG. 11)
In the structure shown in the fifth embodiment, the voltage output circuit 19 is formed inside the power supply case 16 shown in the third embodiment. The voltage output circuit 19 detects a voltage between the electric wire 17 a acquired from the case 9, the contact portion 14 of the power supply case 16, and the electric wire 18 a connected to the power source portion 18. The detected voltage is output via the electric wire 17d. As described in the third embodiment, the power value can be measured from the current of the current sensor 2 detected from 17c and the voltage of the voltage output circuit 19.

  In any of the structures of the first to fourth embodiments, power is supplied from the electric circuit to the current sensor in the case using the contact portion 14 formed directly or via the lead wire in the case 9 that houses the current sensor 2. Since a circuit can be formed, it is not necessary to separately supply a power supply line dedicated to the current sensor 2 to supply power, and complicated wiring work can be omitted when installing the current measuring means.

DESCRIPTION OF SYMBOLS 1 Bus bar 2 Current sensor 3 Main breaker 4 Lead bar 5 Branch breaker 5a Current sensor insertion part 6 Board | substrate 7 Arm part 8 Magnetic detection element 9 Case 10 Integrated circuit 11 Case arm part 12 Plug terminal part 13 Electric circuit 14 Contact part 15 Lead Wire 16 Power supply case 17 Electric wire 18 Power supply unit 19 Voltage output circuit

Claims (5)

A current measuring member that measures the current flowing in the electric circuit that feeds power to the electric device housed in the housing, or the electric circuit inside the electric device housed in the housing,
The current is measured by a pair of arms projecting from one end of the substrate and the inside thereof being used as a wire insertion part having an open end, and a magnetic sensor is arranged on each of the pair of arms. Is performed on the electric circuit,
The current sensor is held in a case covering the substrate,
A current measuring member characterized in that a contact portion in contact with an electric path is formed as means for supplying power to a current sensor in a case.   The current measuring member according to claim 1, further comprising a plug terminal portion that can be elastically inserted into an electric path between arms of the current sensor, and a contact portion is formed on the plug terminal portion.   The current measuring member according to claim 1, further comprising a power supply unit including a rectifying unit in the case. Have multiple cases holding current sensors,
Each case is mounted on a different phase electric circuit, and the power source of the current sensor formed in one case is supplied by a contact portion formed in one case and a contact portion formed in the other case. The current measuring member according to claim 3.   The current measuring member according to claim 4, wherein a voltage detection circuit for detecting a voltage from the contact portion formed in one case and the contact portion formed in the other case is formed.