JPH0377236U - - Google Patents

Description

[Brief explanation of drawings]

Figure 1...Circuit configuration diagram of the earth leakage detector according to the first embodiment of the present invention, Figure 2...Operation time chart of the earth leakage detector of Figure 1, Figure 3...Circuit configuration diagram of the entire earth leakage breaker, Fig. 4...Circuit configuration diagram of a conventional earth leakage detector, Fig. 5...Operation time chart of a conventional earth leakage detector, Fig. 6...Circuit configuration diagram of an earth leakage detector according to the second embodiment of the present invention. Figure 7: An example of an applied circuit of the present invention. 2... Zero-phase current transformer, 4... Comparator, 6... First capacitor, 7... Latch circuit, 12... Thyristor, 1
3... Ripple smoothing capacitor, 14... Voltage drop resistor, 15... Half-wave rectifier diode, 16...
Tripping coil, 21...resistance.

Claims (1)

[Claims for Utility Model Registration] (1) A comparison circuit that amplifies the secondary output voltage of a zero-phase current transformer and compares it with a reference value, a first capacitor charged by the output of the comparison path, and a first When the voltage between the charging voltage terminal of the capacitor and the ground line reaches a certain value, an output signal is generated, and from then on, the voltage between the charging voltage terminal of the first capacitor and the ground line is maintained at the constant voltage. An earth leakage detection circuit having a latch circuit that continues to hold an output signal, a thyristor that is turned on using the output signal of the earth leakage detection circuit as a trigger, and a half-wave rectified voltage is supplied to the anode of the thyristor via a tripping coil. , in an earth leakage detector in which a power supply voltage is supplied from the anode of the thyristor to the ripple smoothing capacitor and the earth leakage detection circuit via a voltage drop resistor, between the first capacitor and the earth line,
An earth leakage detector characterized in that a voltage generating means is inserted that generates voltage undulations according to a tripping current flowing between an anode and a cathode of a thyristor. (2) The voltage generating means is an impedance between the gate and cathode of the thyristor, and an end of the first capacitor on the ground line side is connected to the gate of the thyristor. , the earth leakage detector described in claim (1) of the utility model registration. (3) The voltage generating means is a resistor connected between the cathode of the thyristor and a ground line, and the end of the first capacitor on the ground line side is connected to a connection point between the cathode of the thyristor and the resistor. An earth leakage detector according to claim (1) of the utility model registration claim, characterized in that: