Current transformer unit and monitoring system

Abstract

To facilitate power monitoring in a circuit breaker unit without increasing a board size in a current transformer unit.SOLUTION: Provided is a current transformer unit in which two current transformers and a conductor to be connected to a breaker are built in a casing.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a current transformer unit and a monitoring system. [Background technology]

[0002] An example of prior art is Patent Document 1. Patent Document 1 discloses an internal accessory device that is a cassette of an earth leakage action output switch 5. This earth leakage action output switch 5 is used to output an earth leakage tripping operation of a circuit breaker as an electrical signal.

[0003] Furthermore, if a current transformer (CT) is installed on the secondary side of the circuit breaker, power monitoring can be performed using general-purpose measuring equipment, and current transformers are generally installed on the R and T phases of the circuit breaker. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-299727 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, a device that can be retrofitted to a circuit breaker is built into the circuit breaker, making it possible to output and display an electrical signal. Because it is built into the circuit breaker, it can be made smaller, but detection is required by a device inside the earth leakage breaker, and detection and output cannot be performed within a single device.

[0006] Furthermore, when monitoring power, two separate current transformers must be attached to the circuit breaker, which poses the problem of increasing the size of the panel to ensure sufficient working space and increasing the labor required to manufacture the panel.

[0007] An object of the present invention is to facilitate power monitoring for each breaker in a current transformer unit without increasing the panel size. [Means for solving the problem]

[0008] A current transformer unit according to one embodiment of the present invention is characterized by having a first conductor and a second conductor that pass through a housing and are connected to a circuit breaker, a first magnetic body and a first coil arranged to generate a first electromagnetic induction related to the first conductor, a second magnetic body and a second coil arranged to generate a second electromagnetic induction related to the second conductor, a first terminal that outputs a first electrical signal generated by the first electromagnetic induction, and a second terminal that outputs a second electrical signal generated by the second electromagnetic induction. [Effects of the Invention]

[0009] According to one aspect of the present invention, in a current transformer unit, power monitoring can be facilitated for each breaker without increasing the panel size. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a power monitoring system. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] 1A and 1B are diagrams showing the housing, in which (a) is a front view, (b) is a rear view, (c) is a left side view, (d) is a right side view, (e) is a plan view, and (f) is a bottom view. [Figure 5] 1A and 1B are diagrams showing a circuit breaker and a current transformer unit, in which (a) is a front view and (b) is a perspective view. [Figure 6] 1A and 1B are conceptual diagrams showing the internal structure of the housing, where (a) is a front view and (b) is a plan view. [Figure 7] These are conceptual diagrams of a current transformer unit, where (a) is a plan view and (b) is an internal configuration diagram. [Figure 8] FIG. 2 is a front view showing a protective cover that connects the housing and the circuit breaker. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment will be described with reference to the drawings. [Example]

[0012] The present invention relates to a unit connectable to a circuit breaker. In particular, the present invention relates to a current transformer unit having a built-in current transformer (CT) connectable to the secondary side of a circuit breaker. Here, the term "circuit breaker" refers to a breaker.

[0013] FIG. 1 is a schematic diagram of a power monitoring system.

[0014] Voltage is received from the power company at a power receiving point 101, transformed by a transformer 102, and flows to a circuit breaker 104 for wiring via a current transformer 103 on the secondary side of the transformer.

[0015] The power monitoring system has a monitoring unit that monitors electrical equipment using the current value from a current transformer 105. The power monitoring unit has a general-purpose measuring instrument 106 that measures the current value and a display 107 that displays the current value. A current transformer unit containing two current transformers 105 is placed in a branch circuit of a switchboard.

[0016] The current transformer unit of the present invention is a device that can be retrofitted and connected to circuit breaker 104. In particular, to monitor power using the current transformer on the secondary side of circuit breaker 104, two current transformers 105 must be installed. Therefore, in the present invention, by unitizing a housing that houses two current transformers 105, it is possible to achieve miniaturization, ease of work in panel manufacturing, design, and space savings. The current value transformed by current transformer 105 inside the housing is output to general-purpose measuring device 106, and the current value is displayed on display 107 connected to general-purpose measuring device 106.

[0017] Figures 2 to 7 show the housing, the connection to the circuit breaker, and the internal structure of the current transformer unit.

[0018] The housing 111 has a conductor penetration portion 114 through which the conductors 112 of the three main circuit lines pass, and the housing 111 houses two current transformers 119 and 120 for measuring the two lines on both sides.

[0019] The primary side of the conductor 112 is connected to the secondary side of the circuit breaker 115 by a bolt through the connecting hole 121. On the other hand, the secondary side of the conductor 112 is connected to a load device (for example, a motor) through the connecting hole 122.

[0020] The surface of the housing 111 has a cover mounting hole 108 for protecting the kl terminal 110 and exposed conductive parts, and a housing mounting hole 109 that allows the housing to be mounted independently. The kl terminal 110 is connected to a general-purpose measuring device 106 using a crimp terminal and lead wire, and the current value is output to the general-purpose measuring device 106. Power can be monitored by connecting the general-purpose measuring device 106 to a display 107.

[0021] The housing 111 has a conductor penetration portion 114 for mounting the conductor 112 in a state where it penetrates the current transformers 119 and 120 inside the housing 111. It also has a wiring auxiliary portion 113, and is structured so that lead wires can be routed from the KL terminal 110 along the housing 111. This structure improves workability inside the panel. The wiring auxiliary portion 113 functions as a guide when connecting the KL terminal 110 to the general-purpose measuring instrument 106 via a crimp terminal and lead wire. The housing 111 also has a cover mounting hole 108.

[0022] The housing 111 is attached to the circuit breaker 115 via the housing mounting holes 109. This attachment is performed using, for example, screws. With this structure, the housing 111 can be attached independently to the circuit breaker 115. Two current transformers 119 and 120 are built into the housing 111 and made into a unit, which simplifies panel work.

[0023] 6 and 7, the current transformer unit includes a first conductor 116 and a second conductor 118 that penetrate the housing 111 and are connected to the circuit breaker 115, a first magnetic body 124 and a first coil 123 that are arranged to generate a first electromagnetic induction related to the first conductor 116, a second magnetic body 124 and a second coil 123 that are arranged to generate a second electromagnetic induction related to the second conductor 118, a first terminal 110 that outputs a first electric signal generated by the first electromagnetic induction, and a second terminal 110 that outputs a second electric signal generated by the second electromagnetic induction. The housing 111 is configured to be freely attachable to the circuit breaker 115.

[0024] The first conductor 116, the first magnetic body 124, and the first coil 123 constitute a first current transformer 119. The second conductor 118, the second magnetic body 124, and the second coil 123 constitute a second current transformer 120. The first current transformer 119 and the second current transformer 120 are built into the housing 111 so as to be able to be retrofitted to the circuit breaker 115.

[0025] The first conductor 116 constitutes a first current transformer 119 by passing through a first conductor penetration portion 114 formed by a first magnetic body 124 and a first coil 123. The second conductor 118 constitutes a second current transformer 120 by passing through a second conductor penetration portion 114 formed by a second magnetic body 124 and a second coil 123.

[0026] Here, the first conductor 116 constituting the first current transformer 119 is an R-phase conductor, and the second conductor 118 constituting the second current transformer 120 is a T-phase conductor. The first conductor 116 constituting the first current transformer 119 and the second conductor 118 constituting the second current transformer 120 are configured to be connectable to the secondary side of the circuit breaker 115 and a load device. Also, a third S-phase conductor 117 is provided which penetrates the housing 111 and is connected to the circuit breaker 115. Furthermore, a wiring 125 is provided which is connected to the Kl terminal 110. Here, the magnetic body 124 is, for example, an iron core.

[0027] Only the first conductor 116 (R phase) and the third conductor 118 (T phase) pass through current transformers 119 and 120, allowing electrical signals from each phase to be output from the Kl terminal 110.

[0028] As shown in Fig. 8, after wiring to the KL terminal 110, a protective cover 126 is attached to connect the housing 111 and the circuit breaker 115 using the cover attachment hole 108. In Fig. 8(a), an opaque protective cover 126 is attached, and in Fig. 8(b), a transparent protective cover 126 is attached. The protective cover 126 protects the KL terminal 110 and the conductive exposed portion of the conductor penetration portion 114. In the above embodiment, a current transformer unit is formed by a housing 111 incorporating two current transformers 119 and 120 required for power monitoring, and a conductor 112 for connecting to a circuit breaker 115. This current transformer unit enables detection and output within the device.

[0029] According to the above embodiment, the current transformer unit incorporating the two current transformers 119 and 120 can be made smaller in size, approaching the size of a circuit breaker. This facilitates power monitoring for each circuit breaker without increasing the panel size. Furthermore, power monitoring for each branch line can be easily realized. [Explanation of symbols]

[0030] 101: power receiving point, 102: transformer, 103: transformer secondary side current transformer, 104: molded-case circuit breaker, 105: circuit breaker secondary side current transformer, 106: example of general-purpose measuring equipment, 107: display, 108: cover mounting hole, 109: housing mounting hole, 110: kl terminal part, 111: housing, 112: conductor, 113: wiring auxiliary part, 114: conductor penetration part, 115: circuit breaker, 116: first conductor (R phase), 117: second conductor (S phase), 118: third conductor (T phase), 119: first current transformer (R phase), 120: second current transformer (T phase)

Claims

1. a first conductor and a second conductor for passing through the housing and connecting to the circuit breaker; a first magnetic body and a first coil arranged to generate a first electromagnetic induction related to the first conductor; a second magnetic body and a second coil arranged to generate a second electromagnetic induction related to the second conductor; a first terminal that outputs a first electrical signal generated by the first electromagnetic induction; a second terminal that outputs a second electrical signal generated by the second electromagnetic induction; A current transformer unit comprising:

2. 2. A current transformer unit according to claim 1, The housing includes: A current transformer unit configured to be freely attached to the circuit breaker.

3. 2. A current transformer unit according to claim 1, the first conductor, the first magnetic body, and the first coil constitute a first current transformer; the second conductor, the second magnetic body, and the second coil constitute a second current transformer; The current transformer unit is characterized in that the first current transformer and the second current transformer are built into the housing so as to be retrofittable to the circuit breaker.

4. 4. A current transformer unit according to claim 3, The first conductor includes: a first conductor penetrating portion formed by the first magnetic body and the first coil is penetrated to form the first current transformer; The second conductor is A current transformer unit comprising the second current transformer by passing a second conductor through a second conductor penetration portion formed by the second magnetic body and the second coil.

5. 2. A current transformer unit according to claim 1, the first conductor is an R-phase conductor, The current transformer unit is characterized in that the second conductor is a T-phase conductor.

6. 2. A current transformer unit according to claim 1, The first conductor and the second conductor are A current transformer unit configured to be connectable to the secondary side of the circuit breaker and to a load device.

7. 2. A current transformer unit according to claim 1, a third conductor passing through the housing and connecting to the circuit breaker;

8. 8. A current transformer unit according to claim 7, The current transformer unit is characterized in that the third conductor is an S-phase conductor.

9. 2. A current transformer unit according to claim 1, A current transformer unit comprising a protective cover connecting the housing and the circuit breaker.

10. 2. A monitoring system comprising a monitoring unit that monitors an electric device using a current value from the current transformer unit according to claim 1.

11. 11. The monitoring system of claim 10, The monitoring unit a general-purpose measuring device that measures the current value; a display device that displays the current value; A monitoring system comprising:

12. 11. The monitoring system of claim 10, A monitoring system characterized in that the current transformer unit is arranged in a branch circuit of a distribution board.

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