Residual-current circuit breaker

Abstract

The invention provides a residual-current circuit breaker which does not need a light-emitting element of an optical insulation unit and can reduce the space of a substrate. A residual-current circuit breaker (100) is provided with: a single-phase full-wave rectifier circuit (10) connected to an AC circuit; a diode (12b), the positive electrode of which is connected to the output positive side of the single-phase full-wave rectifier circuit (10); a capacitor (12d) connected to the negative electrode of the diode (12b); a pulse generation circuit (13b) that generates a pulse synchronized with the voltage on the positive electrode side of the diode (12b); and a transmission circuit (13c) that generates a test current for testing the health of the leakage detection circuit (7) in synchronization with the output pulse of the pulse generation circuit (13b).

Description

Technical Field

[0001] The present invention relates to a leakage circuit breaker that detects a leakage current flowing in an alternating current circuit such as a distribution system and opens the alternating current circuit to prevent a leakage accident in advance. Background Art

[0002] Existing leakage circuit breakers have: a main circuit connected to an alternating current circuit; an opening / closing unit including an opening / closing mechanism for opening and closing the main circuit; a leakage detection circuit for detecting a leakage current flowing in the main circuit; a tripping device that, when the leakage detection circuit detects a leakage current, trips the opening / closing mechanism of the opening / closing unit to open the main circuit; and a test circuit for flowing a test current in the leakage detection circuit to confirm the operation of the leakage tripping function.

[0003] Existing general leakage circuit breakers obtain the operating power supply for the leakage detection circuit and the tripping device from two-phase circuits of the main circuit. Existing general leakage circuit breakers also obtain the operating power supply for the test circuit from the main circuit, and based on this operating power supply, a test current (for example, refer to Patent Document 1) that is suppressed to a predetermined value by a resistor flows in the test circuit.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2009-89574

[0005] The existing leakage circuit breaker disclosed in Patent Document 1 has a light-emitting element disposed on the primary side and a light-receiving element disposed on the secondary side. The light-emitting element is inserted between the alternating current circuit and the rectifying circuit, and the light-receiving element is connected to a current limiting element that limits an analog leakage current flowing in the test winding. Thus, the existing leakage circuit breaker disclosed in Patent Document 1 generates a test current synchronized with the alternating current waveform. The light-emitting element of the optical insulation unit is more susceptible to aging deterioration than other electronic components, so the lifespan needs to be considered. In addition, the following problem exists in the existing leakage circuit breaker, that is, in order to connect the primary side of the rectifying circuit and the stepped-down secondary side, it is necessary to ensure a substrate space including an insulation distance. Summary of the Invention

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to obtain a leakage circuit breaker that does not require a light-emitting element of an optical insulation unit and can reduce the substrate space.

[0007] In order to solve the above problems and achieve the object, the leakage circuit breaker according to the present invention includes: a rectifying circuit connected to an AC circuit; a diode whose positive electrode is connected to the positive output side of the rectifying circuit; a capacitor connected to the negative electrode of the diode; a pulse generation circuit that generates a pulse synchronized with the voltage on the positive electrode side of the diode; and a test current generation circuit that generates a test current for testing the health of the leakage detection circuit synchronously with the output pulse of the pulse generation circuit.

[0008] Effects of the Invention

[0009] The leakage circuit breaker according to the present invention has the following effects, that is, it does not require the light-emitting element of the optical insulation unit and can reduce the substrate space. Description of the Drawings

[0010] Figure 1 is a circuit diagram of the leakage circuit breaker according to the embodiment.

[0011] Figure 2 is a circuit diagram showing details of the pulse generation circuit included in the leakage test circuit of the leakage circuit breaker according to the embodiment.

[0012] Figure 3 is a circuit diagram showing details of the transmission circuit included in the leakage test circuit of the leakage circuit breaker according to the embodiment.

[0013] Figure 4 is the first diagram for explaining the operation of the transmission circuit included in the leakage test circuit of the leakage circuit breaker according to the embodiment.

[0014] Figure 5 is the second diagram for explaining the operation of the transmission circuit included in the leakage test circuit of the leakage circuit breaker according to the embodiment.

[0015] Figure 6 is a diagram for explaining the operation of the leakage test circuit of the leakage circuit breaker according to the embodiment. Detailed Embodiment

[0016] Hereinafter, the leakage circuit breaker according to the embodiment will be described in detail with reference to the drawings.

[0017] Embodiment.

[0018] Figure 1It is a circuit diagram of the leakage circuit breaker 100 involved in the embodiment. The leakage circuit breaker 100 has a power supply side connection terminal 1, a load side connection terminal 2, and a main circuit 3 that connects the power supply side connection terminal 1 and the load side connection terminal 2. The main circuit 3 has three circuits: the R phase, the S phase, and the T phase. The circuits are conductors. The leakage circuit breaker 100 also has an opening and closing mechanism section 4 and an opening and closing contact 5 that opens and closes the main circuit 3. The opening and closing contact 5 is driven by the opening and closing mechanism section 4.

[0019] The leakage circuit breaker 100 also has a zero-sequence current transformer 6 through which all phases of the circuits in the main circuit 3 pass. The zero-sequence current transformer 6 has: a secondary winding 6a for detecting the leakage current flowing in the main circuit 3; and a tertiary winding 6b for performing a test of the leakage detection. The leakage current also includes a ground fault current. The leakage circuit breaker 100 also has a leakage detection circuit 7 that monitors the current signal of the secondary winding 6a of the zero-sequence current transformer 6 to determine the presence or absence of leakage. Leakage also includes grounding.

[0020] The leakage circuit breaker 100 also has: a trip device 8 that, when leakage occurs, drives the opening and closing mechanism section 4 through the output signal of the leakage detection circuit 7 to trip the opening and closing contact 5 and open the main circuit 3; a first impedance element 9a connected to the R-phase circuit of the main circuit 3; and a second impedance element 9b connected to the T-phase circuit of the main circuit 3. Each of the first impedance element 9a and the second impedance element 9b is, for example, a resistor or an inductor.

[0021] The leakage circuit breaker 100 also has a single-phase full-wave rectifier circuit 10 that converts the AC power supplied from the main circuit 3 via the first impedance element 9a and the second impedance element 9b into DC power. The leakage circuit breaker 100 also has: a voltage suppression element 11 connected to both ends of the DC side of the single-phase full-wave rectifier circuit 10; and a power supply circuit 12 that converts the DC power supplied from the single-phase full-wave rectifier circuit 10 into DC power with a voltage lower than that of the DC power and supplies operating power to the leakage detection circuit 7 and the trip device 8. The leakage circuit breaker 100 also has a leakage test circuit 13 and a test switch 14. If the test switch 14 is pressed, the leakage test circuit 13 is driven, and an approximate leakage current flows in the tertiary winding 6b.

[0022] The leakage circuit breaker 100 is connected to a three-phase AC circuit that should be detected for leakage through the power supply side connection terminal 1 and the load side connection terminal 2. The three-phase AC circuit is not shown.

[0023] The single-phase full-wave rectifier circuit 10 is composed of four rectifier diodes, rectifies the three-phase AC voltage supplied via the main circuit 3, and supplies DC power to the power supply circuit 12. The four rectifier diodes are not shown. The AC side of the single-phase full-wave rectifier circuit 10 is connected to the R-phase and T-phase circuits of the main circuit 3 via the first impedance element 9a and the second impedance element 9b.

[0024] Each group includes two rectifier diodes that constitute the positive-side bridge arm and the negative-side bridge arm of each phase of the single-phase full-wave rectifier circuit 10. The voltage suppression element 11 is connected in parallel to the two groups respectively. The voltage suppression element 11 suppresses the reverse voltage for all four rectifier diodes, so as to protect the entire circuit including the leakage circuit breaker 100 that also includes the single-phase full-wave rectifier circuit 10 from overvoltages such as surges or pulses. The voltage suppression element 11 is, for example, a Zener diode.

[0025] The power supply circuit 12 has: a first constant voltage circuit 12a, which is supplied with the DC voltage VD full-wave rectified by the single-phase full-wave rectifier circuit 10 and steps down the DC voltage VD to a predetermined first DC control voltage VS; and a diode 12b, whose positive electrode is connected to the first constant voltage circuit 12a. The first constant voltage circuit 12a is a step-down circuit connected to the single-phase full-wave rectifier circuit 10 and the diode 12b. The first DC control voltage VS is, for example, 40V DC.

[0026] The power supply circuit 12 also has a second constant voltage circuit 12c that is supplied with DC power from the first constant voltage circuit 12a via the diode 12b and steps down the first DC control voltage VS of the DC power to a voltage lower than the first DC control voltage VS, i.e., the second DC control voltage VC. The second DC control voltage VC is, for example, 5V DC. The power supply circuit 12 also has a capacitor 12d connected to the negative electrode of the diode 12b and the ground GND for smoothing the first DC control voltage VS.

[0027] Next, the details of the leakage test circuit 13 that performs the leakage test operation will be described. The leakage test circuit 13 has: a Zener diode 13a, whose negative electrode is connected to the positive electrode of the diode 12b of the power supply circuit 12; a pulse generation circuit 13b, which is connected to the positive electrode of the Zener diode 13a and the ground GND, and is driven when the test switch 14 is pressed; and a transmission circuit 13c, which is connected to the negative electrode of the Zener diode 13a and the ground GND, and based on the pulse from the pulse generation circuit 13b, an approximate leakage current flows in the tertiary winding 6b of the zero-sequence current transformer 6. The transmission circuit 13c is, for example, an H-bridge circuit that generates a test current through on-off operation according to the first DC control voltage VS stepped down by the power supply circuit 12.

[0028] The test operation for leakage current is the following operation, that is, by flowing an approximate leakage current through the tertiary winding 6b of the zero-sequence current transformer 6, an approximate leakage is caused to occur, and the leakage detection circuit 7 detects the leakage to perform a leakage trip. For example, when the sensitivity current of the leakage circuit breaker 100 is 500 mA and the tertiary winding 6b is a winding with 100 turns, since a current about twice as much needs to flow, the approximate leakage current becomes 500 (mA) × 2 (times) / 100 (turns) = 10 mA, and the value of the approximate leakage current needs to be set to a current value of about 10 mA.

[0029] Figure 2 It is a circuit diagram showing details of the pulse generation circuit 13b included in the leakage test circuit 13 of the leakage circuit breaker 100 according to the embodiment. The pulse generation circuit 13b includes a transistor 13b1, a resistor 13b2, a resistor 13b3, and a resistor 13b4. The base of the transistor 13b1 is connected to the positive electrode of the Zener diode 13a via the resistor 13b2, and the collector of the transistor 13b1 is connected to the transmission circuit 13c. In Figure 2 the Zener diode 13a included in the leakage test circuit 13 is also shown. The resistor 13b3 is connected to the base and the emitter of the transistor 13b1. The end of the two ends of the resistor 13b3 that is connected to the emitter of the transistor 13b1 is also connected to the ground GND. One end of the resistor 13b4 is connected to the test switch 14, and the other end of the resistor 13b4 is connected to the collector of the transistor 13b1.

[0030] Figure 3 It is a circuit diagram showing details of the transmission circuit 13c included in the leakage test circuit 13 of the leakage circuit breaker 100 according to the embodiment. The transmission circuit 13c includes: a transistor 13c1, whose emitter is connected to the positive electrode of the diode 12b and whose collector is connected to one end of the tertiary winding 6b; a transistor 13c2, whose emitter is connected to the positive electrode of the diode 12b and whose collector is connected to the other end of the tertiary winding 6b; a resistor 13c3, which is connected to the base and the emitter of the transistor 13c1; and a resistor 13c4, which is connected to the base and the emitter of the transistor 13c2.

[0031] The transmission circuit 13c further includes: a resistor 13c5, which is connected to the base of the transistor 13c1 and the collector of the transistor 13c2; a resistor 13c6, which is connected to the base of the transistor 13c2 and the collector of the transistor 13c1; a transistor 13c7, whose collector is connected to the other end of the tertiary winding 6b and whose emitter is connected to the ground GND; and a transistor 13c8, whose collector is connected to one end of the tertiary winding 6b and whose emitter is connected to the ground GND.

[0032] The transmission circuit 13c further includes: a capacitor 13c9 having one end connected to the base of the transistor 13c7 and the other end connected to the collector of the transistor 13b1; a capacitor 13c10 having one end connected to the base of the transistor 13c8 and the other end connected to the collector of the transistor 13b1; and a diode 13c11 having its cathode connected to the collector of the transistor 13c7. In Figure 3 also shown are the transistor 13b1 and the resistor 13b2 of the pulse generation circuit 13b included in the leakage test circuit 13.

[0033] The transmission circuit 13c further includes: a diode 13c12 having its cathode connected to the collector of the transistor 13c8; a resistor 13c13 having one end connected to the anode of the diode 13c11 and the other end connected to the test switch 14; a resistor 13c14 having one end connected to the anode of the diode 13c12 and the other end connected to the test switch 14; and a capacitor 13c15 having one end connected to the anode of the diode 13c12 and the other end connected to the base of the transistor 13c7.

[0034] The transmission circuit 13c further includes: a capacitor 13c16 having one end connected to the anode of the diode 13c11 and the other end connected to the base of the transistor 13c8; a resistor 13c17 connected in parallel with the capacitor 13c15; a resistor 13c18 connected in parallel with the capacitor 13c16; and a resistor 13c19 having one end connected to the collector of the transistor 13c1 and the other end connected to one end of the tertiary winding 6b.

[0035] Next, the operation of the leakage test circuit 13 will be described. Figure 4 is a first diagram for explaining the operation of the transmission circuit 13c included in the leakage test circuit 13 of the leakage circuit breaker 100 according to the embodiment. Figure 4 shows the test current state on the positive side. Figure 5 is a second diagram for explaining the operation of the transmission circuit 13c included in the leakage test circuit 13 of the leakage circuit breaker 100 according to the embodiment.

[0036] Figure 5 shows the test current state on the negative side. Figure 6 is a diagram for explaining the operation of the leakage test circuit 13 of the leakage circuit breaker 100 according to the embodiment. Figure 6 shows how the voltage of the test switch 14, the first DC control voltage VS, the output signal of the pulse generation circuit 13b, and the test current change over time. The first DC control voltage VS is represented by the statement "voltage of VS".

[0037] When the power supply is turned on from the state where the power supply is not connected, that is, if the test switch 14 is pressed, the power supply is supplied from the second constant voltage circuit 12c to the pulse generation circuit 13b and the transmission circuit 13c, and the capacitors 13c9 and 13c10 are charged via the resistors 13c13, 13c14, 13c17, and 13c18, so that the transistor 13c7 or the transistor 13c8 is turned on.

[0038] At this time, there are fluctuations in the resistance values of the resistors 13c13, 13c14, 13c17, and 13c18, the capacitances of the capacitors 13c9 and 13c10, and the conduction sensitivities of the transistors 13c7 and 13c8. Therefore, one of the transistors 13c7 and 13c8 will turn on first. If one of the transistors 13c7 and 13c8 turns on first, the other will be cut off.

[0039] If the transistor 13c7 is turned on and the transistor 13c8 is cut off, current flows through the resistors 13c3 and 13c5, so the transistor 13c1 is turned on. Conversely, if the transistor 13c8 is turned on and the transistor 13c7 is cut off, current flows through the resistors 13c4 and 13c6, so the transistor 13c2 is turned on.

[0040] Next, as Figure 4 shown, the current situation is set to the state where the transistors 13c7 and 13c1 are turned on and the transistors 13c8 and 13c2 are cut off, that is, the state where a positive test current flows in the tertiary winding 6b, and the operation will be described. Figure 6 The timing t1 is the timing in the state where a positive test current flows in the above-mentioned tertiary winding 6b.

[0041] In the above state, as Figure 4 shown, current is supplied to the base of the transistor 13c7 via the resistor 13c17. The side of the resistor 13c17 of the capacitor 13c9 is positively charged, and the side of the transistor 13b1 is negatively charged. The side of the resistor 13c14 of the capacitor 13c15 is positively charged, and the side of the capacitor 13c9 is negatively charged. The side of the resistor 13c13 of the capacitor 13c16 is negatively charged, and the side of the capacitor 13c10 is positively charged. The side of the capacitor 13c16 of the capacitor 13c10 is negatively charged, and the side of the transistor 13b1 is positively charged. The current supplied from the first constant voltage circuit 12a flows sequentially through the transistor 13c1, the tertiary winding 6b, and the transistor 13c7.

[0042] In the case of the state where the transistors 13c7 and 13c1 are turned on and the transistors 13c8 and 13c2 are cut off, as Figure 6As shown by the timing t2, the voltage on the negative side of the Zener diode 13a, i.e., the first DC control voltage VS, instantaneously decreases. Then, when the first DC control voltage VS recovers, the Zener diode 13a also instantaneously becomes non-conductive, and then the Zener diode 13a becomes conductive.

[0043] If the Zener diode 13a is non-conductive, the transistor 13b1 is cut off. Then, if the Zener diode 13a is conductive, the transistor 13b1 is conductive.

[0044] When the transistor 13b1 changes from cut-off to conductive, the side of the resistor 13c17 of the capacitor 13c9 becomes positively charged. No current flows in the capacitor 13c9, but the side of the resistor 13c18 of the capacitor 13c10 becomes negatively charged. Therefore, a current only instantaneously flows in the capacitor 13c10.

[0045] Thus, as Figure 5 shown, a current flows from the second constant voltage circuit 12c via the resistors 13c13 and 13c18. The side of the resistor 13c18 of the capacitor 13c10 becomes positively charged, the side of the transistor 13b1 becomes negatively charged, and the transistor 13c8 becomes conductive.

[0046] If the transistor 13c8 is conductive, a current sequentially flows in the resistors 13c17, the diode 13c12, and the transistor 13c8. No current flows in the base of the transistor 13c7. Therefore, the transistor 13c7 is cut off. At this time, the side of the resistor 13c14 of the capacitor 13c15 becomes negative, the side of the capacitor 13c9 becomes positive, the side of the resistor 13c17 of the capacitor 13c9 becomes negative, and the side of the transistor 13b1 becomes positive.

[0047] If the transistor 13c7 is cut off, no current flows in the resistors 13c3 and 13c5. Therefore, the transistor 13c1 is cut off. On the contrary, if the transistor 13c8 is conductive, a current flows in the resistors 13c4 and 13c6. Therefore, the transistor 13c2 is conductive.

[0048] As a result, the transistors 13c7 and 13c1 are cut off, and the transistors 13c8 and 13c2 are conductive. The current supplied from the first constant voltage circuit 12a, as Figure 6 shown by the timing t3, sequentially flows in the transistor 13c2, the tertiary winding 6b, and the transistor 13c8. The current flowing in the tertiary winding 6b becomes a negative current in the opposite direction.

[0049] Next, as Figure 5 shown, the description will be made with the current state being that the transistors 13c7 and 13c1 are cut off and the transistors 13c8 and 13c2 are conductive.

[0050] In this state, current is supplied to the base of transistor 13c8 via resistor 13c18. The resistor 13c18 side of capacitor 13c10 is positively charged, and the transistor 13b1 side is negatively charged. The resistor 13c13 side of capacitor 13c16 is positively charged, and the capacitor 13c10 side is negatively charged. The resistor 13c14 side of capacitor 13c15 is negatively charged, and the capacitor 13c9 side is positively charged. The capacitor 13c15 side of capacitor 13c9 is negatively charged, and the transistor 13b1 side is positively charged. The current supplied from the first constant voltage circuit 12a flows successively through transistor 13c2, the tertiary winding 6b, and transistor 13c8.

[0051] When transistors 13c8 and 13c2 are conducting and transistors 13c7 and 13c1 are non-conducting, as shown by the timing t4 in Figure 6 , the voltage on the negative side of Zener diode 13a, i.e., the first DC control voltage VS, instantaneously decreases. Then, when the first DC control voltage VS recovers, Zener diode 13a also instantaneously becomes non-conducting, and then Zener diode 13a becomes conducting.

[0052] If Zener diode 13a is non-conducting, then transistor 13b1 is non-conducting. Then, if Zener diode 13a becomes conducting, then transistor 13b1 becomes conducting.

[0053] When transistor 13b1 changes from non-conducting to conducting, the resistor 13c18 side of capacitor 13c10 is positively charged, and no current flows through capacitor 13c10. However, the resistor 13c17 side of capacitor 13c9 is negatively charged, so only an instantaneous current flows through capacitor 13c9.

[0054] As a result, as shown in Figure 4 , current flows from the second constant voltage circuit 12c via resistors 13c14 and 13c17. The resistor 13c17 side of capacitor 13c9 is positively charged, the transistor 13b1 side is negatively charged, and transistor 13c7 conducts.

[0055] If transistor 13c7 conducts, current flows successively through resistor 13c18, diode 13c11, and transistor 13c7, and no current flows through the base of transistor 13c8, so transistor 13c8 is non-conducting. At this time, the resistor 13c13 side of capacitor 13c16 becomes negative, the capacitor 13c10 side becomes positive, the resistor 13c18 side of capacitor 13c10 becomes negative, and the transistor 13b1 side becomes positive.

[0056] If transistor 13c8 is turned off, no current flows through resistors 13c4 and 13c6, so transistor 13c2 is turned off. Conversely, if transistor 13c7 is turned on, current flows through resistors 13c3 and 13c5, so transistor 13c1 is turned on.

[0057] As a result, transistors 13c2 and 13c8 are turned off, and transistors 13c1 and 13c7 are turned on. The current supplied from the first constant voltage circuit 12a flows successively through transistor 13c1, the tertiary winding 6b, and transistor 13c7 as shown in the timing t5 of Figure 6 , and the current flowing through the tertiary winding 6b becomes a positive current in the opposite direction.

[0058] The leakage circuit breaker 100 according to the embodiment includes: a single-phase full-wave rectifier circuit 10 connected to an AC circuit; a diode 12b whose positive electrode is connected to the positive output side of the single-phase full-wave rectifier circuit 10; a capacitor 12d connected to the negative electrode of the diode 12b; a pulse generation circuit 13b that generates a pulse synchronized with the voltage on the positive electrode side of the diode 12b; and a transmission circuit 13c that is a test current generation circuit that generates a test current for testing the health of the leakage detection circuit 7 synchronously with the output pulse of the pulse generation circuit 13b. Therefore, the leakage test circuit 13 can be constituted only by the low-voltage side, it becomes easy to ensure the insulation distance, and further miniaturization of the leakage circuit breaker 100 can be achieved. That is, the leakage circuit breaker 100 does not require the light-emitting element of the optical insulation unit and can reduce the substrate space.

[0059] As described above, the leakage test circuit 13 can be constituted only by the low-voltage side, so the number of components used in the leakage circuit breaker 100 can be suppressed, and further cost reduction of the leakage circuit breaker 100 can be achieved.

[0060] The leakage circuit breaker 100 has a first constant voltage circuit 12a for the single-phase full-wave rectifier circuit 10 and the diode 12b. The pulse generation circuit 13b generates a pulse synchronized with the voltage on the output side of the first constant voltage circuit 12a. Therefore, by using the leakage circuit breaker 100, a highly reliable leakage test can be implemented.

[0061] The pulse generation circuit 13b detects the timing when the voltage on the output side of the first constant voltage circuit 12a rises from the lower limit voltage and turns on the output pulse. Therefore, a pulse synchronized with the voltage on the output side of the first constant voltage circuit 12a can be generated, and a test current waveform that is easy for the leakage detection circuit 7 to detect can be generated.

[0062] The pulse generation circuit 13b detects the voltage on the output side of the first constant voltage circuit 12a through the Zener diode 13a, and generates a pulse synchronized with the detected voltage. Therefore, the circuit of the leakage circuit breaker 100 can be configured at low cost.

[0063] The structure shown in the above embodiment represents an example, and it is also possible to combine with other known technologies, and a part of the structure can be omitted or changed without departing from the gist.

[0064] Description of reference numerals

[0065] 1 Power supply side connection terminal, 2 Load side connection terminal, 3 Main circuit, 4 Opening and closing mechanism part, 5 Opening and closing contact, 6 Zero-sequence current transformer, 6a Secondary winding, 6b Tertiary winding, 7 Leakage detection circuit, 8 Tripping device, 9a First impedance element, 9b Second impedance element, 10 Single-phase full-wave rectifier circuit, 11 Voltage suppression element, 12 Power supply circuit, 13 Leakage test circuit, 14 Test switch, 12a First constant voltage circuit, 12b, 13c11, 13c12 Diodes, 12c Second constant voltage circuit, 12d, 13c9, 13c10, 13c15, 13c16 Capacitors, 13a Zener diode, 13b Pulse generation circuit, 13c Transmission circuit, 13b1, 13c1, 13c2, 13c7, 13c8 Transistors, 13b2, 13b3, 13b4, 13c3, 13c4, 13c5, 13c6, 13c13, 13c14, 13c17, 13c18, 13c19 Resistors, 100 Leakage circuit breaker.

Claims

1. A leakage circuit breaker, characterized in that, it has: a rectifier circuit connected to an AC circuit; a diode, the positive electrode of which is connected to the positive output side of the rectifier circuit; a capacitor connected to the negative electrode of the diode; a pulse generation circuit that generates a pulse synchronized with the voltage on the positive electrode side of the diode; and a test current generation circuit that generates a test current for testing the health of the leakage detection circuit synchronously with the output pulse of the pulse generation circuit.

2. The leakage circuit breaker according to claim 1, characterized in that, it further has a step-down circuit connected to the rectifier circuit and the diode, and the pulse generation circuit generates a pulse synchronized with the voltage on the output side of the step-down circuit.

3. The leakage circuit breaker according to claim 2, characterized in that, the pulse generation circuit detects the timing when the voltage on the output side of the step-down circuit rises from the lower limit voltage and turns on the output pulse.

4. The leakage circuit breaker according to claim 3, characterized in that, the pulse generation circuit detects the voltage on the output side of the step-down circuit through a Zener diode and generates a pulse synchronized with the output side voltage.

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