JP2008277166A - Circuit breaker unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide, with a product cost and a development period on development suppressed, a circuit breaker unit capable of, even if a leakage current component out of a leakage current flowing through alternate current electric paths and equipment increases, preventing unnecessary movement and adequately preventing an electrification accident or a leakage fire due to insufficient insulation of the alternate current electric paths and the equipment by the operation on the basis of an earth fault current flowing to the ground due to the insufficient insulation of the alternate current electric paths and equipment, and moreover to provide a circuit breaker unit capable of being used as conventionally done depending on the user's operation condition by the operation based on the detection of the leakage current. <P>SOLUTION: The circuit breaker unit is provided with tripping means for, when earth fault current detecting means detects the earth fault current, receiving an operation signal from the earth fault current detecting means, and hence acting on a contact point opening/closing mechanism disposed in the circuit breaker unit to open the contact point due to the earth fault current. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a circuit breaker having a function of detecting a ground fault current component in a leakage current in an AC circuit or equipment.

Generally, in places where electricity is used, circuit breakers and earth leakage breakers are installed for the purpose of protecting electric wiring and preventing electric shock accidents due to electric leakage.

When the leakage current detected in the electric circuit reaches a predetermined sensitivity current value, the electric leakage circuit breaker opens the contact provided in the electric leakage circuit breaker to interrupt the electric circuit.

By the way, in recent years, there are an increasing number of circuits that require continuous power supply, such as factory power distribution equipment and power supplies for various machine tools. However, the situation that power supply is necessary is increasing.

In such a case, by installing a circuit breaker with a leakage alarm as shown in Non-Patent Document 1, the leakage current in the circuit reaches a predetermined sensitivity current value. Instead of interrupting the electric circuit, a leakage alarm contact signal is output from the leakage alarm contact provided in the circuit breaker with a leakage alarm to the outside. Thereby, it can be grasped that the leakage current having the predetermined sensitivity current value is generated in the electric circuit.

  When the circuit breaker with a leakage alarm is installed in a circuit, if the leakage current in the circuit reaches a predetermined sensitivity current value, the leakage alarm provided in the circuit breaker with the leakage alarm is provided. An earth leakage alarm contact signal is output from the contact toward the outside. If an alarm is generated by this, there is a possibility of insulation failure in the electric circuit. Therefore, if necessary, power supply to the electric circuit is stopped, the insulation resistance value in the electric circuit is measured, and the insulation defect is appropriately improved. There is a need.

TENPAR INDUSTRY General Catalog 53P-54P 2006-2007 Edition Magazine Electrical Equipment Issuer OHM Co., Ltd. March 2007 Volume 36, Volume 3, Volume 431 Front 42P-Front 48P Photo 2

However, the leakage current includes the ground fault current component (resistance leakage current) that flows to the ground due to insulation faults in AC circuits and equipment, and the leakage that flows from the live parts of the circuit cables and equipment to the ground when there is no insulation failure. Since it is represented by the vector sum of the current component (capacitance leakage current), the contribution of the leakage current component increases due to the increase in the ground capacitance depending on the construction conditions of the circuit, and as a result of the vector sum, The leakage current may reach the sensitivity current value.

In such a case, even if an alarm is received and the insulation resistance measurement is actually performed on the AC circuit or equipment, the insulation resistance value in the normal range may be maintained, and the effect of the insulation resistance measurement work is obtained. It may not be possible.

That is, due to the leakage alarm from the circuit breaker with a leakage alarm, there is a need to stop the power supply to the circuit and to measure the insulation resistance value for inspection and measurement of insulation failure. If this is an unnecessary operation due to leakage current components, a large production loss may be incurred due to the shutdown of power distribution equipment and various machine tools in the factory.

As a device for detecting the ground fault current as described above in the electric circuit, a method of detecting an insulation monitoring device as shown in Non-Patent Document 2 by installing it in the electric circuit is common. In this case, it is necessary to newly install and operate a monitoring device separately from the circuit breaker, and there is a problem that work costs and equipment costs for installing the monitoring device increase.

Therefore, the present invention operates based on the ground fault current component flowing to the ground due to poor insulation of the AC circuit or facility even if the leakage current component of the leakage current flowing to the AC circuit or facility is increased. , Circuit breakers that can prevent unnecessary operation and accurately prevent electric shock accidents and leakage fires due to poor insulation of AC circuits and equipment, etc. It is intended to provide. It is another object of the present invention to provide a circuit breaker that can be used in the conventional manner according to the usage situation of the user by detecting the leakage current and performing the operation.

The circuit breaker in the present invention is
Current that flows to the ground due to poor insulation in AC circuits and facilities, and current that flows to ground due to poor insulation in the AC circuits and facilities, etc. The present invention provides a circuit breaker characterized by comprising a ground fault current detecting means for detecting a ground fault current.

As a result, it is possible to detect the ground fault current component that flows to the ground due to insulation faults in AC circuits and equipment, etc., so a circuit breaker that can prevent electric shock accidents and earth leakage fires due to faulty circuit paths is provided. Can be provided.

In addition, when the ground fault current is detected by the ground fault current detecting means, a trip means by a ground fault current that acts on a contact switching mechanism portion of the circuit breaker to open the contact is provided. A circuit breaker is provided by using the above-described feature.

As a result, when a ground fault current is detected by the ground fault current detecting means in the circuit, the circuit breaker can be cut off, and an electric shock or a fire due to a poor insulation of the circuit can be prevented. A circuit breaker that can be prevented can be provided.

Also intervened in the electric circuit,
A contact switching mechanism for turning on and off the electric circuit;
A first trip means that, when a predetermined current flows in the electric circuit, acts on the contact opening / closing mechanism and performs a tripping operation so that the contact opening / closing mechanism performs an opening operation;
A circuit breaker block comprising: a second tripping unit comprising a voltage tripping element that operates in response to a predetermined operation signal and performs a tripping operation so that the contact switching mechanism unit performs an opening operation;
A circuit breaker may be provided by connecting a ground fault current detection block having a ground fault current detection means for detecting a ground fault current in the electric circuit by a connection means.

As a result, when a normal overcurrent or short-circuit current occurs, the circuit breaker block that can shut off the electric circuit by the first trip device and protect the wiring, and the ground fault current detection block that detects the ground fault current Therefore, it is possible to provide a circuit breaker that can be separately configured and manufactured, and that can be manufactured with improved development efficiency by connecting them with connecting means.

The circuit breaker block includes a zero-phase current transformer provided so as to penetrate the electric circuit,
The ground fault current detection means block includes at least:
A power acquisition unit for acquiring power from within the circuit breaker block;
A zero-phase current transformer output signal acquisition unit for acquiring an output signal obtained from the zero-phase current transformer;
A second trip means drive signal transmission unit for outputting a predetermined operation signal to the second trip means when a ground fault current of a predetermined magnitude is detected by the ground fault current detection means; , With
A circuit breaker may be provided by transmitting and receiving power and signals through the power acquisition unit, the zero-phase current transformer output signal acquisition unit, and the second trip means drive signal transmission unit.

As a result, while using the conventional circuit breaker as much as possible, only the information necessary for detecting the ground fault current can be acquired from the circuit breaker side, and the manufacturing efficiency can be increased.

The ground fault current detection means block can change the operation mode taken by the circuit breaker when a ground fault current of a predetermined magnitude is detected, and can be selected from the predetermined operation modes. A circuit breaker may be provided by providing selection means for performing the above operation.

As a result, the operation of the circuit breaker when the ground fault current of the predetermined magnitude is detected by the ground fault current detecting means is suitable from the predetermined operation mode according to the circuit condition and the user's desire. It is possible to provide a circuit breaker that can select the one.

The circuit breaker may also be provided, wherein the operation mode includes at least an alarm mode for outputting an alarm signal from an alarm signal output unit and a notification unit provided in the circuit breaker. Good.

As a result, the fact that a ground fault current of a predetermined magnitude has been detected by the ground fault current detecting means can be recognized in the vicinity of the circuit breaker by an alarm from the notification section, and it is separated from the circuit breaker. In other places, it can be recognized by receiving an alarm signal from the alarm signal output unit, and the alarm can be effectively recognized.

In addition, the current to be detected as an operation factor of the operation of the circuit breaker to generate a breaking operation or an alarm includes at least a leakage current in the electric circuit or a ground fault current in the electric circuit, and a selection for selecting the current to be detected A circuit breaker may be configured by providing means.

As a result, the current to be detected can be selected as appropriate according to the condition of the electric circuit and the user's desire, and a highly convenient circuit breaker can be provided.

According to the circuit breaker of the present invention, even if the leakage current component increases in the leakage current flowing in the AC circuit or equipment, the circuit breaker operates based on the ground fault current flowing to the ground due to the insulation failure of the AC circuit or equipment. In this way, circuit breakers that can prevent unnecessary operations and accurately prevent electric shock accidents and leakage fires due to poor insulation of AC circuits and equipment are manufactured at the time of development. It becomes possible to provide the information with a reduced period. In addition, by detecting the leakage current and performing the operation, it is possible to provide a circuit breaker that can be used as usual according to the usage situation of the user.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, substantially the same parts are denoted by the same reference numerals.

(First embodiment)
<Appearance of circuit breaker>
As a first embodiment, an example of a circuit breaker generally used in a three-wire electric circuit is shown, and its external view is shown in FIGS.

FIG. 1 shows an external view of the circuit breaker during operation.
The circuit breaker 1 is composed of a circuit breaker block 10 that is normally connected to an electric circuit and a ground fault current detection block 20 that detects a ground fault current. The circuit breaker block 10 and the ground fault current detection block 20 have a hook-like projection 21 provided on the ground fault current detection block 20 side as shown in FIG. It is connected by fitting with a concave portion corresponding to the hook-shaped convex portion.

A power supply side terminal 102 and a load side terminal 103 connected to the electric circuit are provided outside the casing of the circuit breaker block 10, and the electric circuit is turned on and off inside the casing of the circuit breaker block 10. A contact opening / closing mechanism portion, an operation handle 101 for driving a portion of the contact opening / closing mechanism portion that is exposed to the outside of the housing, and when a predetermined current such as an overcurrent flows through the electric circuit, the contact point A first trip means comprising a thermal element or an electromagnetic trip element acting on the opening / closing mechanism and performing a tripping operation so that the contact opening / closing mechanism performs an opening operation; and receiving a predetermined operation signal. And a second trip means comprising a voltage trip element for performing a tripping operation so that the contact opening / closing mechanism portion performs an opening operation.

The ground fault current detection block 20 includes
A ground-fault current detecting means for detecting a ground-fault current component in the electric circuit; and when a ground-fault current of a predetermined magnitude is detected by the ground-fault current detecting means, a predetermined value is directed toward the second tripping means. Second tripping means driving means for outputting the operation signal.

The ground fault current detection block 20 includes an alarm display signal when a ground fault current of a predetermined magnitude is detected by the information display operation unit 201 that can be operated or visually recognized from the outside of the housing and the ground fault current detection means. Is output to the outside.

The information display operation unit 201 is provided with a display unit 202 for displaying various information, an operation unit 205 for setting operation conditions of the circuit breaker, and a reset unit 204 for stopping the alarm. The information display operation unit 201, the alarm signal output unit 203, and the ground fault current detecting means are connected to an arithmetic processing circuit to be described later, and the arithmetic processing circuit determines whether to detect the ground fault current in the electric circuit, It is configured to control the operation of the circuit breaker when detecting a fault current.

The circuit breaker block 10 and the ground fault current detection block 20 have a power source acquisition unit, a zero-phase current transformer output signal acquisition unit, and a second tripping unit, which will be described later, in order to transmit and receive power and signals. Means drive signal transmission unit, and these power source acquisition unit, zero phase current transformer output signal acquisition unit, and a hole for drawing out or drawing in the second tripping unit drive signal transmission unit The circuit breaker block 10 and the ground fault current detection block 20 are provided.

<Operation unit>
An enlarged view of the operation unit 205 is shown in FIG.
The operation unit 205 is a push button type operation unit,
A setting item selection unit 205a for setting the operation mode of the circuit breaker block 10,
A setting value determination unit 205b for performing a determination operation on the setting item selected by the setting item selection unit 205a;
A set value increasing unit 205c, a set value decreasing unit 205d for performing an increase / decrease selection operation for setting items such as the sensitivity current value,
A set value confirmation unit 205e for confirming the set value.

<Display section>
The display unit 202 is configured by a liquid crystal display, and the display unit 202 visually displays various setting values for the operation of the circuit breaker and the ratio of the detection target current to the setting value. Then, arithmetic processing is performed in the arithmetic processing circuit in conjunction with the operation unit 205, and items operated on the operation unit 205 are appropriately displayed on the display unit 202.

<Display during operation>
The display unit in FIG. 1 shows various display states during operation of the circuit breaker block 10. In the display unit 202, a detection method in which the breaker block 10 displays a current to be detected as an operation factor of an operation for generating a breaking operation or an alarm,
Sensitivity current that displays the sensitivity current that is the operation threshold for the current to be detected;
A current level indicating a ratio of a current to be detected with respect to the sensitivity current;
The operation mode indicating the operation mode when the current to be detected reaches a predetermined magnitude (sensitivity current) is displayed, and information necessary for operation is displayed so that the user can visually recognize it.

<Display when checking the set value>
Next, the display unit in FIG. 2 shows various display states when the set value of the circuit breaker block 10 is confirmed. In this state, when the set value confirmation unit 205e in the operation unit 205 is pressed, the calculation processing circuit reads the set values stored in the calculation processing circuit, and the various values currently set on the display unit 202 are displayed. Display of set values, that is, the detection method, the sensitivity current, the operation mode, and the operation time until the operation is performed based on the operation mode when the current to be detected reaches the sensitivity current. Do. Thereby, the user can visually recognize the set value of the circuit breaker block 10 by checking the display unit.

<Display at the time of setting>
Next, the display unit in FIGS. 3 to 6 shows a display state when various settings of the circuit breaker block 10 are performed.
In this embodiment, there are three main items as the setting items: the “detection method”, the “sensitivity” for setting the sensitivity current, and the “operation” for setting the operation mode and the operation time. The large items are accompanied by detailed setting items (small items), and will be described step by step.

<Basic selection / decision flow>
First, the basic selection / determination flow will be described.
When making various settings on the circuit breaker block 10, the setting item selection unit 205a is pressed. Then, a signal is input to the arithmetic processing circuit, and the circuit breaker block 10 is switched to the large item selection acceptance standby mode.

In the large item acceptance standby mode, a large item is displayed as a list on the display unit 202, and the setting item to be set is displayed in reverse from other setting items within a predetermined area (inverted cursor overlay). It is easy to see which setting item is selected. The small items are displayed simultaneously with the display of the large items. In this state, when the set value determination unit 205b is pressed, the selected large item is selected and determined, and the mode is switched to the reception standby mode for the small item attached to the large item. At this time, the sub-items are displayed as a list, and the setting item to be set is highlighted with respect to other setting items in a predetermined area, so that it is easy to visually recognize which setting item is selected. It is possible.

Note that the reverse display portion may be configured to blink so that the reverse display and the normal display are repeated so that the selection items become more conspicuous.

The setting item is switched by pressing the setting item selection unit 205a again. Each time the setting item selection unit 205a is pressed between the large items when the large item is selected and between the small items when the small item is selected, another setting item is selected. It is possible to visually recognize which setting item is selected by moving the cursor.

In addition, when determining the setting of the selected setting item, by pressing the set value determining unit 205b, the set processing value is stored in the arithmetic processing unit at the same time.
When the small item is selected, it switches to the selected state of the large item,
When the large item is selected, the operation state is switched.

When the setting item selection unit 205a or the setting value determination unit 205b is pressed and no operation is continued for a predetermined time, the timer processing means that no signal is input to the arithmetic processing circuit. As a result, the operation status display is switched.

<Actual selection / determination operation>
Next, a case where the setting item is selected / determined will be described with reference to FIGS. 3 to 6 based on the basic selection / determination flow described above.

First, in the display at the time of operation shown in FIG. 1 or the display state at the time of confirmation shown in FIG. 2, when the setting item selection unit 205a is pressed, the display unit displays the detection method, the sensitivity, The display switches to the selection display for selecting the major action items.

<Selection detection method>
FIG. 3 shows an initial display state when the display is switched to the selection display. In the initial display state, the cursor is displayed in a reverse overlay at the detection method, and the mode for selecting “detection method” is set. In this state, when the set value determination unit 205b is pressed, the active cursor changes to the current item (Io / Ior / off) to be detected, which is a small item of the detection method, and the set item selection unit 205a is pressed. By doing so, it becomes possible to sequentially select the current items to be detected.

When the set value determination unit 205b is pressed after the desired current item to be detected is selected, the arithmetic processing unit stores the current item to be detected, and the active cursor is again a large item “detection” Transition to "Method". When off is selected in the small item, no current detection processing is performed on the electric circuit.

<Selection action>
Next, when the setting item selection unit 205a is pressed in this state, a mode for selecting the “operation” shown in FIG. 4 is entered. Subsequently, when the set value determination unit 205b is pressed, a mode for selecting “mode” and “time” which are small items is set. In FIG. 4, the mode is selected as alarm and the operation time is selected to be 0.3 seconds.

When the set value determination unit 205b is pressed, the active cursor changes to the “mode” (alarm / blocking / both) to be detected, which is a small item of the detection method, and the set item selection unit 205a is pressed. , Mode items can be selected sequentially.

When the set value determination unit 205b is pressed after the desired mode is selected, the arithmetic processing unit stores the mode item, and the active cursor changes to the “mode” which is a small item again. When the setting item selection unit 205a is pressed again in this state, the active cursor changes to the small item “time” (0.3 seconds / 3 seconds / custom), and the setting item selection unit 205a is pressed. By doing so, time items can be selected sequentially.

When the set value determination unit 205b is pressed after the desired time is selected, the arithmetic processing unit stores the time item, and the active cursor transitions to “mode” and “time”, which are small items again. . Subsequently, when the set value determination unit 205b is pressed, the arithmetic processing unit stores the operation item, and the active cursor is changed to the “operation” which is a large item again.

When “Custom” is selected in the “Time” item of the “Action” item, the time is displayed on the right side of the “Custom” display in the figure as shown in FIG. Using the set value increase unit 205c or the set value decrease unit 205d in 205, the time until the breaker block 10 operates can be freely set.

In this setting, the increase / decrease in time is set using the set value increasing unit 205c or the set value decreasing unit 205d of the operation unit 205. FIG. 5 shows a case where the time until operation is set to 5 minutes. After the setting, when the set value determination unit 205b is pressed, the arithmetic processing unit stores the operation item, and the active cursor changes to a “time” item as a small item. Further, when the set value determining unit 205b is pressed again, the active cursor is changed to the “action” item which is a large item.

<Selection sensitivity>
Next, in this state, when the setting item selection unit 205a is pressed, a mode for selecting "sensitivity" shown in FIG. 6 is entered. Subsequently, when the set value determination unit 205b is pressed, a mode for selecting the sensitivity for each detection target current (Io / Ior), which is a small item, is set.

As in the case of the “operation” item described above, the set item selection unit 205a and the set value determination unit 205b are used to select the desired sensitivity for each detection target current to be set, and then the set value. When the determination unit 205b is pressed, the arithmetic processing unit stores the sensitivity item for each current to be detected, and the active cursor again changes to “sensitivity”, which is a large item.

When “Custom” is selected in the “Io” and “Ior” items of the “sensitivity” item, the sensitivity current is displayed on the right side of the “custom” display, and the setting in the operation unit 205 is performed. By using the value increasing unit 205c or the set value decreasing unit 205d, the “sensitivity” can be freely set for each current to be detected of the circuit breaker block 10.

In addition, with regard to the custom setting of sensitivity, priority is given to the current (Io or Ior) to be detected by the detection method selected in the detection method.

Then, after setting the three major items of the “detection method”, “sensitivity” of the current to be detected, and “operation” for setting the operation mode and the operation time to desired values, the set value When the determination unit 205b is pressed, the operation state is entered, and the display unit displays the detection target current as an operation factor of the above-described shut-off operation or operation for issuing an alarm,
Sensitivity current that displays the sensitivity current that is the operation threshold for the current to be detected;
A current level indicating a ratio of a current to be detected with respect to the sensitivity current;
The operation mode indicating the operation mode when the current to be detected reaches a predetermined magnitude (sensitivity current) is displayed, and information necessary for operation is displayed so that the user can visually recognize it.

Next, an internal processing procedure of the circuit breaker block 10 according to the present invention will be described with reference to FIGS. FIGS. 7 and 8 are block diagrams showing the internal configuration of the circuit breaker block 10 when the electric circuit is a single-phase three-wire system and a three-phase three-wire system, respectively. For reference, an internal processing algorithm in the circuit breaker block 10 is also indicated by an arrow.

<Ground fault current detection means circuit>
<Single-phase three-wire system>
The internal block diagram shown in FIG. 7 is a circuit breaker 1 when applied to a single-phase three-wire electric circuit. Between the circuit breaker block 10 and the ground fault current detection block 20, a power acquisition unit 301 and a zero are shown. A state in which power and signals are transmitted and received through the phase current transformer output signal acquisition unit 302 and the second trip means driving signal transmission unit 303 is shown.

The voltage phase of the electric circuit is L1 phase and L2 phase, and the neutral phase is N phase. 102 is a power supply side terminal of the circuit breaker block 10, and 103 is a load side terminal of the circuit breaker block 10. Reference numeral 104 denotes a contact opening / closing mechanism for turning on and off the electric circuit, which is provided inside the casing of the circuit breaker block 10. Reference numeral 105 denotes second tripping means composed of a voltage tripping element that acts on the contact opening / closing mechanism section to perform an opening operation so that the contact opening / closing mechanism section 104 performs an opening operation. In addition, when a predetermined current flows through the electric circuit, it includes a thermal element or an electromagnetic trip element that acts on the contact switching mechanism and performs a tripping operation so that the contact switching mechanism opens. The description of the first trip means is omitted.

The voltage tripping element drives the plunger in a predetermined direction by electromagnetic induction by applying electric power. The second tripping means 105 is driven by a second tripping means driving means 106 that is driven in response to a cutoff signal output from an arithmetic processing circuit 2007 described later.

Reference numeral 2008 denotes a power supply circuit that performs AC / DC conversion including a rectifier circuit for supplying power to various circuits such as the arithmetic processing circuit unit 2007. The power supply circuit 2008 obtains power from the electric circuit in the circuit breaker block 10 via the power acquisition unit 301, and in the electric circuit, on the secondary side of the contact switching mechanism unit 104 of the circuit breaker block 10, Connected to the L1 phase and the L2 phase to supply power. The connection to the electric circuit may be configured to perform rectification by connecting the N phase and the L1 phase, or the N phase and the L2 phase.

107 is provided so as to penetrate the electric circuit in the circuit breaker block 10, and when a leakage current is generated in the circuit, an output signal (output current) having a magnitude corresponding to the leakage current is generated by electromagnetic induction. It is a zero-phase current transformer that outputs.

The output signal of the zero phase current transformer 107 is input from the circuit breaker block 10 to the ground fault current detection block 20 via the zero phase current transformer output signal acquisition unit 302. The zero-phase current transformer output signal acquisition unit 302 is constituted by a lead wire.

Reference numeral 2005 denotes a leakage current detection circuit, which includes a voltage signal converter that converts the output signal of the zero-phase current transformer 107 into a voltage signal, a differential amplifier that differentially amplifies the voltage signal, and an appropriate size. The level adjustment unit for level adjustment and the low-pass filter unit for removing high-frequency components are input to the arithmetic processing circuit unit 2007.

Reference numeral 2004 denotes a voltage phase detection circuit that is connected to the L1 phase and the L2 phase, which are voltage phases, and detects the voltage phase. The voltage phase detection circuit 2004 includes a differential amplifying unit that differentially amplifies the voltage signals in the L1 phase and the L2 phase, a low-pass filter unit that removes a high frequency component of the voltage waveform obtained from the differential amplifying unit, The output obtained from the low-pass filter unit includes a rectangular wave generating unit that generates a rectangular wave whose high level / low level are inverted at the zero cross point of the voltage, and is input to the arithmetic processing circuit unit 2007.

<Determination of phase wire type>
Reference numeral 2006 denotes a phase / wire type discrimination circuit for discriminating the phase / line type of the electric circuit, and it is determined whether the electric circuit on which the circuit breaker block 10 is installed is a single-phase three-wire type or a three-phase / three-wire type. It is a circuit for discriminating.

The phase line type discrimination circuit 2006 is connected to a phase that is not the voltage phase in the electric circuit (the N phase that is the ground phase in FIG. 7 and the V phase that is the ground phase in FIG. 8), and an input unit on the electric circuit side. Therefore, the voltage protection unit composed of a resistor and a diode for preventing circuit destruction due to reverse voltage, the output signal reversal prevention unit composed of a diode for preventing reverse rotation of the output signal, and a signal for phase and wire type discrimination A capacitor charging / discharging circuit composed of a capacitor for storing electricity and a resistor, and an output unit for outputting the output of the capacitor charging / discharging circuit (FIG. 13).

The output from the output unit is input to the arithmetic processing circuit. When the voltage on the voltage phase in the circuit is full-wave rectified and the negative voltage is the ground voltage, the voltage that is not the voltage phase, that is, the ground phase voltage, does not become negative in the case of a single phase. The output from the output unit is always positive (High level), and in the case of three phases, the output from the output unit is always zero (Low level). Can be determined to be a single-phase three-wire circuit when the output is at a high level, and when the output from the output unit is at a low level, it is a three-phase three-wire circuit.

2007 includes an input of an output signal output from the leakage detection circuit 2005, a voltage phase detection circuit 2004, a phase line type discrimination circuit 2006, an arithmetic processing based on an input of a setting signal output from the operation unit 205,
An arithmetic processing circuit unit that performs display control on the display unit 202 and notification control from the alarm signal output unit 203, and is configured using a microcomputer in this embodiment.

The arithmetic processing circuit unit 2007 includes a signal input / output unit, an input signal A / D conversion unit, a storage unit for storing data such as a program, an arithmetic processing unit, and the like.

<Three-phase three-wire type>
The internal block diagram shown in FIG. 8 is a circuit breaker 1 when applied to a three-phase three-wire electric circuit. Between the circuit breaker block 10 and the ground fault current detection block 20, a power acquisition unit 301 and a zero are shown. A state in which power and signals are transmitted and received through the phase current transformer output signal acquisition unit 302 and the second trip means driving signal transmission unit 303 is shown.

The configuration of the circuit breaker block 10 is the same as that of FIG. 7 described above, and the connection to the electric circuit is such that the terminals at both ends of the power supply terminal 102 of the circuit breaker block 10 shown in FIG. The center terminal is connected to the V phase. In addition, when a predetermined current flows through the electric circuit, it includes a thermal element or an electromagnetic trip element that acts on the contact switching mechanism and performs a tripping operation so that the contact switching mechanism opens. The description of the first trip means is omitted.

Reference numeral 2008 denotes a power supply circuit that performs AC / DC conversion including a rectifier circuit for supplying power to various circuits such as the arithmetic processing circuit unit 2007. The power supply circuit 2008 includes two contact opening / closing mechanism units 104 of the circuit breaker block 10 in the electric circuit. On the next side, it is connected to the U-phase and W-phase at both ends of the electric circuit to supply power. The connection to the electric circuit may be configured to perform rectification by connecting to the V phase and the U phase, or the V phase and the U phase.

<Ground fault current detection means Detection method>
Next, a method for detecting a ground fault current when the detection method is Ior will be described step by step.

In this example, as an element used for obtaining the ground fault current,
As external elements, voltage phase data in the electric circuit, leakage current data detected by the zero-phase current transformer 107, and phase line type discrimination data of the electric circuit are used.
Further, when performing a synchronous operation using the external element in the circuit breaker block 10 as an internal element, individual circuit characteristics such as the voltage phase detection circuit 2004, the leakage current detection circuit 2005, and the arithmetic processing circuit unit 2007, respectively. Using the phase correction value for correcting the phase shift from the reference value and the sine wave data whose effective value is 1
The ground fault current is obtained by calculation processing.

<Single-phase three-wire detection method>
First, the case where the electric circuit is a single-phase three-wire system will be described with reference to FIG.

In the arithmetic processing circuit unit 2007, as information from the electric circuit,
Voltage conversion signal data of a leakage current input from a leakage current detection circuit 2005 for converting a leakage current obtained from the zero-phase current transformer 107 into a voltage signal;
Phase wire type discrimination data input from the phase wire type discrimination circuit 2006;
The rectangular wave signal data of the circuit voltage input from the voltage phase detection circuit 2004 is input.

In the arithmetic processing circuit unit 2007, the following steps are executed.
A / D conversion of the voltage conversion signal data of the leakage current input from the leakage current detection circuit 2005 by A / D conversion unit 701 into digital data at predetermined time (step S001),

In addition, using the rectangular wave input from the voltage phase detection circuit 2004, a step of setting the zero cross point of the rising edge of the rectangular wave to the basic start timing (θ) of calculation (step S002),

Also, the phase correction value (δ) is read from the phase correction value storage unit 704, and the phase correction value (δ) is shifted from the basic start timing of the calculation (θ + δ) (step S003),

When the electric circuit is a single-phase three-wire system, that is, when the signal input from the phase-wire system discrimination circuit 2006 is at a high level, the delay data in the time delay setting unit 703 in the figure is set to 0 (zero degree). The delay data (0) is added to the timing shifted by the phase correction value (δ) from the basic start timing (θ) of the calculation (θ + δ + 0) to obtain the calculation start timing (step S004),

A step of reading the sine wave data having the effective value of 1 from the sine wave data storage unit 702 (step S005);

A step of multiplying the voltage conversion signal data of the leakage current A / D converted by the A / D conversion unit 701 by the multiplication unit 705 with the sine wave data (step S006),

A step of averaging one period of the waveform obtained as a result of the multiplication in the average value calculation unit 706 (step S007),

In the level determination unit 709, the sensitivity current data is read from the set value data from the set value storage unit 708, and the average value of one cycle obtained in step S007 is compared with the set sensitivity current data. A level determination step (step S008) for determining that a ground fault current has occurred when the sensitivity current data has been reached;

When the time determination unit 709 determines that a ground fault current has occurred in the level determination unit 709, it reads out time data and operation data from the set value data from the set value storage unit 708. When the ground fault current is generated continuously for the data and the cut-off operation is set in the operation mode, the cut-off signal output unit 710 passes through the second trip means drive signal transmission unit 303. , A step of outputting a cutoff signal to the second tripping means driving means 106 (step S009).

The second tripping means driving means 710 is driven when the shut-off signal is input, whereby a voltage is applied to the second tripping means 105, and the contact opening / closing mechanism 104 is moved. Tripping and opening the contact (step S010).

When the alarm mode is set in the operation mode, a step of outputting a notification signal to the alarm signal output unit 203 (step S011) is executed.

As described above, the sine wave data stored in the arithmetic processing circuit unit 2007 is converted into a sine wave data having an effective value of 1 in advance at predetermined time intervals and stored in the sine wave data storage unit 702. Yes. In the case of this embodiment, in order to detect a ground fault current more accurately, one cycle of sine wave data is divided into 256 points and converted into data, and the amplitude value of the sine wave corresponding to the division point is stored. I am letting. The number of division points is, for example, 128 divisions for simpler detection, depending on the capability of the arithmetic processing circuit unit and the storage capacity, and depending on the desired accuracy, and for more precise detection. It may be determined appropriately such as 512 divisions.

In addition, the alarm signal output unit 203 described above is configured such that the terminals in the figure are closed when a ground fault current is detected.

These notified alarm signals can be stopped by pressing a reset button 2004, and a stop signal is input to the arithmetic processing circuit unit 2007.

<Detection of leakage current>
In the circuit breaker block 10, when the detection method is set to Io, the circuit breaker current is detected without detecting the ground fault current in the electric circuit. In this case, the arithmetic processing circuit unit 2007 does not execute the step (step S006) of multiplying the voltage conversion signal data of the leakage current by the sine wave data, and obtains an average value of one cycle as it is, A level determination is made by comparing with the sensitivity current data set in advance, and an interruption or alarm operation is performed according to the operation mode.

<Level display on display>
Note that the arithmetic processing circuit unit 2007 performs display control on the display unit 202, and a sensitivity set in advance for the value of the ground fault current or the leakage current obtained by the average value calculation unit 712 described above. Calculate the ratio of the current value to the data, and display the level step by step.

In this embodiment, as shown in FIG. 1, four levels are displayed, and each level is less than 25%, 25% to 50%, 50% to 75%, 75 % Or more. For example, when the magnitude of the detected ground fault current is about 30% of the sensitivity current, two level displays are lit from the left in the figure.

In this embodiment, the liquid crystal drive control of the display unit 202 is performed by the display control unit 711 of the arithmetic processing circuit unit 2007. However, the circuit may be configured using a separate liquid crystal drive circuit.

<Three-phase three-wire detection method>
Next, the case where the electric circuit is a three-phase three-wire system will be described with reference to FIG.
In the case of the three-phase three-wire system, the data input from the phase-wire type discrimination circuit 2006 to the arithmetic processing circuit unit 2007 is different from that in the case of the single-phase three-wire system.

As described above, in the case of the three-phase three-wire system, a low-level signal is output from the phase-wire type discrimination circuit 2006 to the arithmetic processing circuit unit 2007.

In the case of a three-phase three-wire system, when the arithmetic processing circuit unit 2007 receives a low level signal from the phase / wire type discriminating circuit 2006, the delay data in the time delay setting unit 703 is converted to π / 2 (90 The delay data is further shifted (θ + δ + π / 2) to a timing (θ + δ) shifted by the phase correction value (δ) from the calculation start timing (θ) (θ + δ + π / 2), and the calculation is started as the calculation start timing ( Step S004 ').

Other detection steps are the same as in the case of the single-phase three-wire system described above.

As described above, regardless of whether the circuit is the single-phase three-wire system shown in FIG. 7 or the delta-connected three-phase three-wire system shown in FIG. It is possible to detect a leakage current or a leakage current.

However, when the circuit breaker block 10 of the present invention is installed in a star-connected three-phase three-wire circuit, when the ground fault current is obtained and the first phase as a reference is determined, Since it is difficult to obtain the detection accuracy of the ground fault current in the other two phases, the ground fault current Ior is not detected even when the detection method is set to Ior.

(Second Embodiment)
<Appearance of circuit breaker>
The external structure of the circuit breaker according to the second embodiment is shown in FIG. Compared with the circuit breaker shown in FIG. 1, the ground fault current detection block 20 in the present embodiment replaces the liquid crystal display and the push button type operation unit with the information display operation unit. In addition, it is different in that it is configured by using a mechanical selection type switch.

The information display operation unit in the circuit breaker block 10 shown in FIG.
As an operation part,
A dial type operation unit (detection method operation unit) 205a for selectively selecting a detection method;
A slide-type operation unit (operation time operation unit) 205b for selectively switching the operation time;
A slide-type operation unit (sensitivity setting operation unit) 205c that selectively switches the sensitivity current.
Moreover, as a display part,
A level display unit 202a is provided for level-displaying the ratio of the magnitude of the ground fault current or leakage current in the electric circuit determined by the detection method with respect to the sensitivity current in a stepwise manner.

These operation unit and display unit are connected to an input / output port provided in the arithmetic processing circuit unit 2007, and the setting in the operation unit results in a difference in voltage value at the input port of the arithmetic processing circuit unit 2007. Is input. Further, the level display unit 202a is configured by using an LED, and the arithmetic processing circuit unit 2007 performs lighting display step by step according to the ratio of the detection target current obtained by the calculation.

The dial type operation unit 205a for selectively switching the detection method is:
It is possible to alternatively select three states: Ior for detecting a ground fault current, Io for detecting a leakage current, and a function OFF in which no detection is performed.

The slide type operation unit 205b that selectively switches the operation time is as follows.
An item of 0.3 seconds can be selected alternatively for immediate operation, or 3 seconds for time delay operation.

The slide type operation unit 205c that selectively switches the sensitivity current is as follows.
A detection sensitivity for the detection target current selected in the detection method selection operation unit 205a;
When the detection method is Io, the items of 100 mA with high sensitivity, 200 mA with medium sensitivity, and 500 mA with low sensitivity can be selected alternatively.
Further, when the detection method is Ior, it is possible to alternatively select an item of 30 mA having a high sensitivity, a medium 60 mA, and a 150 mA having a low sensitivity.

Based on the various setting values set in this way, the arithmetic processing circuit unit 2007 performs arithmetic processing for each step described above, and obtains the detection target current set by the detection method.

The level display unit 202a is configured to display four levels, and each level is divided into less than 25%, 25% to 50%, 50% to 75%, 75% or more. ing. For example, when the magnitude of the detected current is about 30% of the sensitivity current, two level displays are lit from the bottom in the figure.

When the detected current reaches the sensitivity current set by the sensitivity setting operation unit 205c and the operation time set by the operation time operation unit 205b has elapsed, a predetermined alarm notification and alarm signal are output. Is output.

(Third embodiment)
An external configuration of the circuit breaker 1 according to the third embodiment is shown in FIG. In the present embodiment, the circuit breaker block 10 is configured using a circuit breaker having a cassette attachment device insertion portion 12 into which a cassette attachment device as shown in FIG. 17 can be inserted.

A power supply side terminal 102 and a load side terminal 103 connected to the electric circuit are provided outside the casing of the circuit breaker block 10, and the electric circuit is turned on and off inside the casing of the circuit breaker block 10. A contact opening / closing mechanism portion, an operation handle 101 for driving a portion of the contact opening / closing mechanism portion that is exposed to the outside of the housing, and when a predetermined current such as an overcurrent flows through the electric circuit, the contact point A first trip means comprising a thermal element or an electromagnetic trip element acting on the opening / closing mechanism and performing a tripping operation so that the contact opening / closing mechanism performs an opening operation; and receiving a predetermined operation signal. And a second trip means comprising a voltage trip element for performing a tripping operation so that the contact opening / closing mechanism portion performs an opening operation.

Further, the ground fault current detection block 20 is configured to be inserted into the cassette attachment device insertion portion, and has an external appearance. By inserting into the cassette attachment device insertion portion, the ground fault current detection block 20 is connected to the breaker block 10. Therefore, it is possible to detect the ground fault current in the electric circuit.

The ground fault current detection block 20 in this embodiment includes
A ground-fault current detecting means for detecting a ground-fault current component in the electric circuit; and when a ground-fault current of a predetermined magnitude is detected by the ground-fault current detecting means, a predetermined value is directed toward the second tripping means. Second trip means driving means for outputting the operation signal of
As in the previous embodiment, a power supply acquisition unit 301, a zero-phase current transformer output signal acquisition unit 302, and a second trip means driving signal transmission unit 303 are provided, and these power acquisition unit, The circuit breaker block 10 and the ground fault current detection block 20 are provided with a hole for drawing out or drawing in the current transformer output signal acquisition unit and the second trip means driving signal transmission unit.

The ground fault current detection block 20 includes an alarm display signal when a ground fault current of a predetermined magnitude is detected by the information display operation unit 201 that can be operated or visually recognized from the outside of the housing and the ground fault current detection means. Is output to the outside.

The information display operation unit 201 is provided with a display unit 202 for displaying various information, an operation unit 205 for setting operation conditions of the circuit breaker, and a reset unit 204 for stopping an alarm. The same operation as in the first embodiment is performed.

It should be noted that the present invention is not limited to the disclosed embodiments, and can be freely improved and changed in design as necessary, without departing from the spirit of the invention.
<Indication of leakage warning>
For example, in order to notify the user that the leakage current is increasing in the circuit, in order to prevent the leakage current in the circuit from reaching the sensitivity current and notifying unnecessary operation of the circuit breaker and unnecessary alarms. In addition, a leakage current caution display means may be provided in the display unit 202.

For example, when the leakage current calculated by the arithmetic processing circuit unit 2007 reaches 50% of the sensitivity current determined by the sensitivity setting operation unit 205c, the leakage current caution display means It is good to operate.

As a result, the user can recognize that the leakage current is generated at least 50% of the sensitivity current in the electric circuit, and the unnecessary operation of the circuit breaker and the unnecessary alarm due to the leakage are notified in advance. Can be prevented. In addition, it is also useful to provide time to take appropriate measures and alert attention before an accident associated with electric leakage occurs.

It is to be noted that the operation of the leakage current caution display means is configured so that the calculation processing circuit unit 2007 always obtains the calculation regardless of whether the detection target current of the detection method is Io or Ior. Good.

<Parallelization of arithmetic processing circuit>
For example, as the arithmetic processing circuit unit 2007, using a microcomputer provided with a plurality of A / D conversion units, an arithmetic process for obtaining Ior and Io in parallel is performed,
It is preferable to perform time division in the course of the arithmetic processing and perform arithmetic processing so as to alternately obtain Ior and Io at each time division point.

FIG. 10 shows a leakage current caution display when the display unit is composed of liquid crystal, and FIG. 11 shows an example of a leakage current caution display when the display unit is composed of LEDs.
In FIG. 10, the arithmetic processing circuit unit 2007 causes the “Io attention” display to be black and white inverted and blinking.
Further, in FIG. 11, the arithmetic processing circuit unit 2007 displays an LED clearly indicating Io attention. It may be displayed blinking.

Further, as shown in FIG. 14 and FIG. 15, as a warning signal, a speaker unit 206 is provided in the ground fault current detection block 20 to reproduce sound data stored in advance in the arithmetic processing circuit unit 2007. You may comprise so that an audio | voice warning may be alert | reported. In addition to the voice processing, it may be configured to simply notify the buzzer sound.

In the second embodiment shown in FIG. 9, means for switching the operation mode in the circuit breaker block 10 is not provided. For this reason, the alarm mode, which is the operation mode, is configured to perform stepwise control from the arithmetic processing circuit unit 2007, and in conjunction with the level display unit 202a, if it exceeds 50%, it is sounded. "The current level of Ior has reached 50%. Please be careful.", If it exceeds 75%, the current level of Ior has become 75%. It may be configured so that an alarm such as “Ior's current level will soon become a sensitivity current. Cut off. Be careful.” To alert the surroundings.

Further, the connecting means shown in FIG. 18 may be configured to be connected using a double-sided tape or the like by using an adhesive means or an adhesive means as a simpler one.

The connection position when the ground fault current detection block 20 is connected to the circuit breaker block 10 is not only the left side as shown in the previous embodiment, but also the connection on the right side, You may comprise so that it may connect on the power supply side terminal side or the load side terminal side. In addition, when connecting on the power supply side terminal side or the load side terminal side, the ground fault current detection block 20 can be fixed by connecting so as to connect to the terminal screw portion.

The present invention can be used as a circuit breaker used in a distribution board for houses intervening in an electric circuit instead of a circuit breaker that has been widely used in the past. Can protect against fire and electric shock.

The figure which shows the external appearance structure at the time of operation | use of the circuit breaker by 1st Embodiment. The figure which shows the external appearance structure at the time of the confirmation of the circuit breaker by 1st Embodiment The figure which shows the external appearance structure at the time of the setting of the circuit breaker by 1st Embodiment The figure which shows the external appearance structure at the time of the setting of the circuit breaker by 1st Embodiment The figure which shows the external appearance structure at the time of the setting of the circuit breaker by 1st Embodiment The figure which shows the external appearance structure at the time of the setting of the circuit breaker by 1st Embodiment The figure which shows the block block diagram of the circuit breaker by 1st Embodiment The figure which shows the block block diagram of the circuit breaker by 1st Embodiment The figure which shows the external appearance structure at the time of operation | use of the circuit breaker by 2nd Embodiment. Example of electric leakage warning display Example of electric leakage warning display Illustration of the operation unit Example of phase wire discrimination circuit Other applications Other applications The figure which shows the external appearance structure of the earth-leakage circuit breaker by 3rd Embodiment. The figure which shows the external appearance structure of the earth-leakage circuit breaker by 3rd Embodiment. The figure which shows the connection means of a ground-fault current detection block and a circuit breaker block

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Circuit breaker 101 Handle 102 Power supply side terminal part 103 Load side terminal part 104 Contact switching mechanism part 105 Voltage trip element 106 Second trip means drive means 107 Zero phase current transformer 701 A / D conversion part 702 Sine wave Data storage unit 703 Time delay setting unit 704 Phase correction value setting unit storage unit 705 Multiplication unit 706 Average value calculation unit 707 Level determination unit 708 Setting value storage unit 709 Time determination unit 710 Second trip means driving means 711 Display control unit 201 Information Display Operation Unit 202 Display Unit 203 Alarm Signal Output Unit 204 Reset Unit 205 Operation Unit 206 Speaker Unit 2004 Voltage Phase Detection Circuit 2005 Leakage Current Detection Circuit 2006 Phase and Wire Type Discriminating Circuit 2007 Arithmetic Processing Circuit Unit

Claims (7)

Current that flows to the ground due to poor insulation in AC circuits and facilities, and current that flows to ground due to poor insulation in the AC circuits and facilities, etc. A circuit breaker comprising ground fault current detecting means for detecting a ground fault current. When the ground fault current is detected by the ground fault current detecting means, a trip means by a ground fault current that acts on a contact switching mechanism portion of the circuit breaker to open the contact is provided. The circuit breaker according to claim 1, wherein: Intervening in the circuit,
A contact switching mechanism for turning on and off the electric circuit;
A first trip means that, when a predetermined current flows in the electric circuit, acts on the contact opening / closing mechanism and performs a tripping operation so that the contact opening / closing mechanism performs an opening operation;
A circuit breaker block comprising: a second tripping unit comprising a voltage tripping element that operates in response to a predetermined operation signal and performs a tripping operation so that the contact switching mechanism unit performs an opening operation;
3. The circuit breaker according to claim 1, wherein a ground fault current detection block having a ground fault current detection means for detecting a ground fault current in the electric circuit is connected by a connection means. In the circuit breaker block, a zero-phase current transformer provided so as to penetrate the electric circuit,
The ground fault current detection means block includes at least:
A power acquisition unit for acquiring power from within the circuit breaker block;
A zero-phase current transformer output signal acquisition unit for acquiring an output signal obtained from the zero-phase current transformer;
A second trip means drive signal transmission unit for outputting a predetermined operation signal to the second trip means when a ground fault current of a predetermined magnitude is detected by the ground fault current detection means; , With
4. The circuit breaker according to claim 3, wherein power and signals are transmitted and received through the power acquisition unit, the zero-phase current transformer output signal acquisition unit, and the second trip means driving signal transmission unit. In the ground fault current detection means block,
A selection means is provided for selecting an operation mode to be taken by the circuit breaker from a predetermined operation mode when a ground fault current of a predetermined magnitude is detected by the ground fault current detection means. The circuit breaker according to claim 4. The operation mode is at least
6. The circuit breaker according to claim 5, further comprising an alarm mode for outputting an alarm signal from an alarm signal output unit and a notification unit provided in the circuit breaker. The current to be detected as an operation factor of the operation in which the circuit breaker performs a breaking operation or an alarm includes at least a leakage current in the electric circuit or a ground fault current in the electric circuit, and selection means for selecting the current to be detected is provided. The circuit breaker according to claim 6, wherein the circuit breaker is provided.

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