CN212627136U

CN212627136U - Earth wire leakage current detection circuit of leakage protector

Info

Publication number: CN212627136U
Application number: CN202021948546.7U
Authority: CN
Inventors: 倪圣富
Original assignee: Zhejiang Chengfu Electric Appliance Technology Co ltd
Current assignee: Zhejiang Chengfu Electric Appliance Technology Co ltd
Priority date: 2020-09-04
Filing date: 2020-09-04
Publication date: 2021-02-26
Anticipated expiration: 2030-09-04

Abstract

The utility model relates to a leakage protection technical field just discloses a leakage protector ground wire leakage current detection circuitry, including ground wire leakage current control, ground wire leakage current control is connected with ground wire leakage current transformer, zero sequence current transformer, amplifies triode, dropout drive control, leakage protection chip, dropout relay, first resistance and second resistance. The utility model discloses a earth leakage protection chip possesses zero sequence earth leakage protection and ground wire earth leakage protection simultaneously, separates zero sequence electric leakage and ground wire electric leakage completely and does not influence mutually between the two, has reduced earth leakage protector's components and parts quantity when reaching the power consumption safety protection to reach reduction in production cost and the effect of reducing the product volume.

Description

Earth wire leakage current detection circuit of leakage protector

Technical Field

The utility model relates to an earth leakage protection technical field especially relates to an earth leakage protector ground wire leakage current detection circuitry.

Background

One leakage protection chip in the existing leakage protector product cannot simultaneously have zero sequence leakage protection and ground wire leakage protection, and zero sequence leakage protection and ground wire leakage protection can be completely realized only by using two or more leakage protection chips, so that the increase of the number of the leakage protection chips greatly restricts the miniaturization development of the leakage protector product while influencing the production cost of the leakage protector product.

SUMMERY OF THE UTILITY MODEL

The purpose of the utility model is to solve the shortcoming that exists among the prior art, if: one leakage protection chip in the existing leakage protector product cannot simultaneously have zero sequence leakage protection and ground wire leakage protection, and zero sequence leakage protection and ground wire leakage protection can be completely realized only by using two or more leakage protection chips.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the ground wire leakage current control is connected with a ground wire leakage current transformer, a zero sequence current transformer, an amplifying triode, a tripping drive control, a leakage protection chip, a tripping relay, a first resistor and a second resistor.

Preferably, the control electrode and the cathode of the ground leakage current control are directly connected in parallel at two ends of the ground leakage current transformer.

Preferably, the output pin of the amplifying triode acts on the end a of the leakage protection chip through a first resistor, or the base and the emitter of the triode are connected in parallel at two ends of the ground leakage current transformer, and the amplifying triode, the triode and the second resistor form a self-locking control loop.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses a earth leakage protection chip possesses zero sequence earth leakage protection and ground wire earth leakage protection simultaneously, separates zero sequence electric leakage and ground wire electric leakage completely and does not influence mutually between the two, has reduced earth leakage protector's components and parts quantity when reaching the power consumption safety protection to reach reduction in production cost and the effect of reducing the product volume.

Drawings

Fig. 1 is a schematic structural diagram of the application of Q1 and Q2 of the present invention;

fig. 2 is a schematic diagram of an application structure of Q1 according to the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Referring to fig. 1-2, a ground leakage current detection circuit of a leakage protector comprises a ground leakage current control SCR1, the ground leakage current control SCR1 is connected with a ground leakage current transformer ZCT1, a zero sequence current transformer ZCT2, an amplifying triode Q1, a triode Q2, a tripping drive control SCR2, a leakage protection chip U1, a tripping relay L1, a first resistor R3 and a second resistor R10, a control electrode and a cathode of the ground leakage current control SCR1 are directly connected in parallel at two ends of the ground leakage current transformer ZCT1, an output pin of the amplifying triode Q1 acts on an a end of the leakage protection chip U1 through the first resistor R3, or a base electrode and an emitter electrode of the triode Q2 are connected in parallel at two ends of the ground leakage current transformer ZCT1, and the amplifying triode Q1, a triode Q2 and the second resistor R10 form a self-locking control loop.

The utility model discloses in, adopt a earth leakage protection chip U1 to possess zero sequence earth leakage protection and ground wire earth leakage protection simultaneously, with zero sequence electric leakage and ground wire electric leakage separately completely and between the two not influence mutually, reduced earth leakage protector's components and parts quantity when reaching the power consumption safety protection to reach reduction in production cost and reduce the effect of product volume.

The specific implementation steps are as follows:

s1, the ground wire leakage current control SCR1 is used for detecting the ground wire leakage current;

s2, when a ground wire leakage current transformer ZCT1 has leakage current, the ground wire leakage current controls the conduction of an SCR1 and the conduction of an amplifying triode Q1, and the low voltage of a power supply acts on a pin A of a leakage protection chip U1 through a first resistor R3;

s3, the pin B of the leakage protection chip U1 outputs high voltage to enable the tripping drive control SCR2 to be conducted;

s4, the tripping relay L1 obtains electricity, the leakage protector is tripped, and ground wire leakage current protection is formed;

s5, when the earth leakage current transformer ZCT1 detects leakage current;

s6, the triode Q2 and the amplifying triode Q1 are electrified, and power supply voltage supplies power to the triode Q2 through the second resistor R10, so that self-locking control of the amplifying triode Q1 and the triode Q2 is realized;

s7, the amplifying triode Q1 is powered on continuously, when voltage acts on the pin A of the leakage protection chip U1 through the first resistor R3, the pin B of the leakage protection chip U1 outputs high voltage to enable the tripping drive control SCR2 to be conducted;

s8, the tripping relay L1 obtains electricity, the leakage protector is tripped, and ground wire leakage current protection is formed;

and S9, when leakage current passes through a coil of the zero-sequence current transformer ZCT2, the zero-sequence current transformer ZCT2 outputs voltage to the leakage protection chip U1, and at the moment, a pin B of the leakage protection chip U1 outputs high voltage to enable the tripping drive control SCR2 to be conducted, the tripping relay L1 obtains power, and the leakage protector is tripped to form zero-sequence leakage current protection.

The above, only be the concrete implementation of the preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art is in the technical scope of the present invention, according to the technical solution of the present invention and the utility model, the concept of which is equivalent to replace or change, should be covered within the protection scope of the present invention.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Claims

1. The ground wire leakage current detection circuit of the leakage protector comprises a ground wire leakage current control (SCR1) and is characterized in that the ground wire leakage current control (SCR1) is connected with a ground wire leakage current transformer (ZCT1), a zero-sequence current transformer (ZCT2), an amplifying triode (Q1), a triode (Q2), a tripping drive control (SCR2), a leakage protection chip (U1), a tripping relay (L1), a first resistor (R3) and a second resistor (R10), a control electrode and a cathode of the ground wire leakage current control (SCR1) are directly connected to two ends of the ground wire leakage current transformer (ZCT1) in parallel, an output pin of the amplifying triode (Q1) acts on an A end of the leakage protection chip (U1) through the first resistor (R3), or a base electrode and an emitter electrode of the triode (Q2) are connected to two ends of the leakage current transformer (ZCT1) in parallel, and an amplifying triode (Q1) and a triode (Q2), The second resistor (R10) forms a self-locking control loop.