WO2018188364A1

WO2018188364A1 - Electromagnetic leakage protection circuit

Info

Publication number: WO2018188364A1
Application number: PCT/CN2017/115426
Authority: WO
Inventors: 邹建华
Original assignee: 中山市开普电器有限公司
Priority date: 2017-04-12
Filing date: 2017-12-11
Publication date: 2018-10-18
Also published as: CN206712446U

Abstract

An electromagnetic leakage protection circuit, comprising a shell (1) provided therein with an alternating-current input interface (2) and an alternating-current output interface (3); a leakage switch (4) is provided between the alternating-current input interface (2) and the alternating-current output interface (3); a zero sequence current transformer (5) sleeved on an alternating-current power line for detecting the leakage current is provided between the leakage switch (4) and the alternating-current output interface (3); a diode (D1) is connected between two output ends of the zero sequence current transformer (5); a trip coil (L1) for controlling disconnection of the leakage switch (4) according to the leakage current detected by the zero sequence current transformer (5) is connected in parallel to the diode (D1), thereby realizing irrelevance to the power voltage value, and disconnecting a power switch when the leakage value reaches the setting value.

Description

Electromagnetic leakage protection circuit

[Technical field]

The utility model relates to an electromagnetic leakage protection circuit.

[Background technique]

At present, most of the mobile leakage protectors on the market are leakage protectors of electronic leakage protection circuits, but the electronic leakage protector has its fatal defect. When the input power supply voltage is under voltage, even if there is leakage, the protection The device will not trip and power off. At this time, the personal safety is not guaranteed, and the transistor has weak impact resistance and poor environmental resistance. At the same time, the electronic leakage protector needs auxiliary working power, and the leakage characteristics are easily affected by the working voltage. The effect of fluctuations; on the other hand, when the main circuit is out of phase, the leakage protector loses its protection function.

[utility content]

The utility model overcomes the deficiencies of the above technology, and provides an electromagnetic leakage protection circuit that disconnects the power switch when the leakage value reaches the set value regardless of the power supply voltage value.

In order to achieve the above object, the utility model adopts the following technical solutions:

An electromagnetic leakage protection circuit includes a housing 1 in which an AC input interface 2 and an AC output interface 3 are disposed, and an AC leakage switch 4 is disposed between the AC input interface 2 and the AC output interface 3, A zero-sequence current transformer 5 is disposed between the leakage switch 4 and the AC output interface 3 for detecting a leakage current on the AC power line, and a diode D1 is connected between the two output ends of the zero-sequence current transformer 5, The diode D1 is connected in parallel with the trip coil L1 that controls the leakage switch 4 to be turned off according to the magnitude of the leakage current detected by the zero-sequence current transformer 5.

A test switch 6 is connected to an input end of the zero-sequence current transformer 5, and the other end of the test switch 6 is connected to a neutral line, and the other input end of the zero-sequence current transformer 5 is connected to the fire line through a resistor R1. Pick up.

The AC input interface 2 includes a neutral input interface 21 and a live input interface 22, and the AC output interface 3 includes a neutral output interface 31 and a live output interface 32.

A thermistor MOV1 is connected between the live line and the neutral line.

The beneficial effects of the utility model are:

The leakage and power-off operation of the utility model has nothing to do with the voltage value of the input power source. When the zero-sequence current transformer detects that the leakage value reaches the set value, the leakage switch is disconnected, the power supply is cut off, and the user's personal safety is better protected. At the same time, the utility model has strong impact resistance, strong anti-environment interference, no auxiliary working power supply, and is not affected by the fluctuation of the working voltage. Even if the main circuit is in phase, the leakage protection circuit of the utility model can work normally.

[Description of the Drawings]

Figure 1 is a schematic view of the utility model.

[detailed description]

The embodiments of the present invention are further described in detail below with reference to the accompanying drawings:

As shown in FIG. 1 , an electromagnetic leakage protection circuit includes a housing 1 , and an AC input interface 2 and an AC output interface 3 are disposed in the housing 1 , and the AC input interface 2 and the AC output interface 3 are disposed between the AC input interface 2 and the AC output interface 3 . The leakage switch 4 is provided with a zero-sequence current transformer 5 disposed on the AC power line for detecting leakage current between the leakage switch 4 and the AC output interface 3, between the two output ends of the zero-sequence current transformer 5 A diode D1 is connected, and the diode D1 is connected in parallel with a trip coil L1 that controls the leakage switch 4 to be turned off according to the magnitude of the leakage current detected by the zero-sequence current transformer 5.

The AC input interface 2 includes a zero line input interface 21 and a hot line input interface 22, and the AC output interface 3 includes a zero line output interface 31 and a live line output interface 32, and the live line and zero. A thermistor MOV1 is connected between the lines.

The working principle is as follows:

When the leakage switch 4 is pressed, when leakage occurs, the leakage current generates an induced current through the zero-sequence current transformer 5, and the induced current is transmitted to the trip coil L1 through the diode D1 to generate an electromagnetic induction force, when the induced current reaches the set value. The electromagnetic induction force generated by the trip coil L1 drives the electromagnetic trip mechanism to operate, disconnects the leakage switch 4, and cuts off the power.

A test switch 6 is connected to an input end of the zero-sequence current transformer 5, and the other end of the test switch 6 is connected to a neutral line, and the other input end of the zero-sequence current transformer 5 is connected to a live line through a resistor R1 for Test whether the leakage protection circuit works normally. After the leakage switch 4 is pressed, the test switch 6 is triggered to form a short circuit. When the short-circuit current passes through the zero-sequence current transformer 5, an induced current exceeding the set value is generated, if the trip coil The electromagnetic induction force generated by L1 drives the electromagnetic tripping mechanism to work, disconnects the leakage switch 4, and cuts off the power supply, and the leakage protection circuit can work normally, otherwise the leakage protection circuit fails.

Claims

An electromagnetic leakage protection circuit is characterized in that it comprises a casing (1), wherein the casing (1) is provided with an AC input interface (2) and an AC output interface (3), and the AC input interface (2) is A leakage switch (4) is disposed between the AC output interfaces (3), and a zero-sequence current mutual inductance is set between the leakage switch (4) and the AC output interface (3) for detecting leakage current between the AC power lines. The diode (1) is connected between the two output ends of the zero-sequence current transformer (5), and the diode D1 is connected in parallel with the leakage current detected by the zero-sequence current transformer (5) to control the leakage switch. (4) The trip coil L1 that is disconnected.
The electromagnetic leakage protection circuit according to claim 1, wherein a test switch (6) is connected to an input end of the zero-sequence current transformer (5), and the other end of the test switch (6) is A neutral connection, the other input of the zero sequence current transformer (5) is connected to the live line through a resistor R1.
The electromagnetic leakage protection circuit according to claim 1, wherein the AC input interface (2) comprises a neutral input interface (21) and a live input interface (22), and the AC output interface ( 3) Includes a zero line output interface (31) and a live line output interface (32).
An electromagnetic leakage protection circuit according to claim 3, wherein a thermistor MOV1 is connected between the live line and the neutral line.