CN2276678Y

CN2276678Y - Domestic single-phase zero power-off earth leakage protective device

Info

Publication number: CN2276678Y
Application number: CN 94223003
Authority: CN
Inventors: 袁英; 梁怀均
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-10-17
Filing date: 1994-10-17
Publication date: 1998-03-18
Anticipated expiration: 2004-10-17

Abstract

The utility model relates to a domestic single-phase zero power-off earth leakage protective device, which can prevent earth leakage and personal electric shock from occurring. An or gate circuit is added in an earth leakage protective device with the orderly and electrical connecting structure of an electromagnet coil of a mechanical tripping switch, a unidirectional controlled silicon element and diodes in the existing insulating casing. Two diodes connected in series in the or gate circuit are orderly and electrically connected with the unidirectional controlled silicon element and the electromagnet coil of the mechanical tripping switch according to consistent conducting direction; the cathode of the other diode is electrically connected with a conducting wire between two series diodes; the anode is electrically connected with the wire connecting terminal of an earth wire. When an input line normally runs or the input line generates the power off of a zero wire, if the earth leakage of a device or personal electric shock occurs, the protective device can automatically make the contact points of the mechanical tripping switch separated and cut off the power supply for playing the role of safety protection.

Description

Family expenses single-phase zero disconnected earth leakage protective device

The utility model relates to a kind of earth leakage protective device, especially can prevent the family expenses single-phase zero disconnected earth leakage protective device that leak electricity in zero line outage back, the person gets an electric shock.

At present, known single-phase earth leakage protective device is to be made of insulation crust, mechanical dropout switching device, contact switch, current transformer, several parts of electronic element circuit.When equipment electric leakage, its electric current of person electric shock occurring above set quota, provide a voltage by current transformer and make circuits for triggering that electronic component forms electromagnet coil power machinery dropout switching device, under the effect of electromagnet suction, contact switch in the mechanical dropout switching device is separated reach the purpose of cutting off the electricity supply.But; this can only move under the normal situation at the input voltage circuit and work; as zero line outage appears; it has just lost protective effect; this is because the working power of earth leakage protective device is to rely on live wire and zero line work; so under the zero line powering-off state; earth leakage protective device has only live wire and can not form the loop makes its work; this moment is if leak electricity; the accident of human electric shock; live wire over the ground; or to the leakage current of human body no matter numerical value have muchly, the earth leakage protective device contact switch is separated, do not have protective effect; one of key in the electrical safety technology is that zero line can not cut off the power supply, but is difficult to guarantee in actual motion.The main cause that the zero line outage takes place has the following aspects to cause: on the first zero line fuse is housed; It two is that the zero line line ball is loosening; It three is that accident is done.General single-phase earth leakage protective device can not shield under the zero line powering-off state effectively, and this has just constituted extremely dangerous hidden danger in the safety utilization of electric power.

The purpose of this utility model provides a kind of family expenses single-phase zero disconnected earth leakage protective device, and it can not only just often be worked in the operation of input voltage circuit, also can play the safeguard protection effect under the zero line powering-off state.

The purpose of this utility model is achieved in that two input wires terminals is housed on insulation crust, and two lead-out terminals, an earth terminal are housed below.In insulation crust, the contact of two input wires terminals, two mechanical dropout switches is linked in sequence and is electrically connected with two lead-out terminals after two leads pass current transformer together, an internal circuit operating voltage is set takes out from input zero line binding post, output hot terminal respectively.The gate circuit of forming by 3 diodes, machinery dropout switch electromagnet coil, the one-way SCR element, diode is electrically connected with operating voltage, test button, test resistance is in parallel with it, current mutual inductor coil is connected electrically in two inputs of the bridge rectifier of 4 diodes compositions respectively, the output head anode of bridge rectifier is electrically connected with the control utmost point of one-way SCR element, negative pole is connected with the cathodic electricity of one-way SCR element, between the negative electrode of one-way SCR element and the control utmost point, be electrically connected an electrolytic capacitor, two diodes are connected in series and a little are electrically connected with another diode cathode in the gate circuit, and the anode of this diode is electrically connected with earth terminal.When power consumption equipment leaks electricity; when person shock current surpasses set quota; the alternating voltage that current mutual inductor coil is inducted becomes direct voltage after the bridge rectifier rectification; this voltage is more than or equal to the trigger voltage of one-way SCR element; be added between the control utmost point of one-way SCR element and the negative electrode and make its conducting; electric current is by the series diode of zero line in gate circuit; machinery dropout switch electromagnet coil; the one-way SCR element; diode constitutes the loop to live wire; at this moment mechanical dropout switch electromagnetic actuation; switch contact is disconnected; protective effect has been played in the circuit outage.After the zero line outage takes place in the input power cord road, at this moment the live wire that has only by the single-phase earth leakage protective device of family expenses, this moment is if power consumption equipment leaks electricity, the person gets an electric shock, when its electric current surpasses set quota, become direct voltage after the alternating current pressuring meridian rectification circuit rectification that current mutual inductor coil is inducted, this voltage is more than or equal to the trigger voltage of one-way SCR element; Be added between the control utmost point of one-way SCR element and the negative electrode and make its conducting; electric current constitutes the loop by ground wire another series diode, mechanical dropout switch electromagnet coil, one-way SCR element, diode in gate circuit to live wire; at this moment mechanical dropout switch electromagnetic actuation; switch contact is separated; protective effect has been played in the circuit outage.After the electric leakage accident was got rid of, the mechanical dropout switch that closes can continue the energising operation.Like this, no matter be circuit operation normal condition or under the zero line powering-off state, can both shield, reached the purpose of safeguard protection.

Owing to adopt such scheme, can be in the operation of input power cord road normal or carry out safeguard protection easily when the zero line outage takes place, only add in the circuit OR circuit element be electrically connected, simple in structure.

Below in conjunction with drawings and Examples the utility model is further specified.

Fig. 1 is circuit theory diagrams of the present utility model.

Fig. 2 is the planar configuration figure of the single-phase zero disconnected earth leakage protective device embodiment of family expenses, also as Figure of abstract.

Among the figure: 1, mechanical dropout switch 2, input live wire (phase line) binding post 3, input zero line binding post 4, mechanical dropout switch contact 5, OR circuit; 6, mechanical dropout switch electromagnet coil; 7, one-way SCR element 8, electrolytic capacitor 9, bridge rectifier 10, diode 11, test button 12, insulation crust 13, test resistance 14, ground wire binding post 15, output zero line binding post 16, output live wire (phase line) binding post 17, current transformer 18, wiring board 19, wiring board 20, contact 21, lead 22, screw A=90mm B=64mm

In Fig. 1, test button (11), test resistance (13) series connection link to each other with machinery dropout switch zero line contact chip (20), output wiring terminal (16) respectively; OR circuit (5), mechanical dropout switching circuit magnetic coil (6), one-way SCR (7), diode (10) are series at mechanical dropout switch zero line contact chip, output live wire (phase line) binding post; Current transformer (17) coil lead is connected on the input circuit of bridge rectifier (9) respectively; The output cathode of bridge rectifier (9) extremely links to each other with the control of one-way SCR (7), and negative pole links to each other with the negative electrode of one-way SCR element (7), is connected an electrolytic capacitor between the control utmost point and negative electrode; From connecting another diode between OR circuit (5) series diode, the anode of this diode links to each other with the ground wire binding post.All parts all are contained in the shell (12) of insulation.

Claims

1, a kind of family expenses single-phase zero disconnected earth leakage protective device, in insulation crust, mechanical dropout switch electromagnet coil, one-way SCR element, diode are pressed the consistent order of conducting direction and are electrically connected.Test button, test resistance is in parallel with above circuit, current transformer is electrically connected with the input of bridge rectifier, the output head anode of bridge rectifier is electrically connected with the control utmost point of one-way SCR element, negative pole is connected with the cathodic electricity of one-way SCR element, it is characterized in that: two diodes are by in the consistent circuit that is connected on mechanical dropout switch electromagnet coil and one-way SCR element with one-way SCR element conductive direction in the OR circuit that is made of 3 diodes, the negative electrode of another diode is electrically connected with lead between two series diodes, and anode is electrically connected with the ground wire binding post.