Ground wire safety voltage control system

Abstract

The invention relates to a ground wire safety voltage control system which comprises a power supply circuit, a detection circuit, a processing circuit and an output circuit, wherein the output circuit is connected with an interruption device with a load in a connecting manner, the power supply circuit is connected between a live wire and a zero wire and used for providing a power supply for a control system; the detection circuit is used for detecting a ground wire voltage and outputting a control signal to the processing circuit when the voltage difference between the ground wire voltage and the zero wire voltage reaches a preset safety voltage range; and the processing circuit is used for processing the ground wire voltage according to the control signal and controlling the output circuit to trigger the external interruption device to interrupt to switch off the connection between the power supply and the load. When detecting that the ground wire voltage reaches a preset range or the zero wire and the live wire are connected inversely, the detection circuit triggers a leakage protection plug to trip and alarm through the processing circuit and the output circuit, the connection between the power supply and the load is switched off, thus the purpose of preventing fire or electric shock is achieved and the use safety of electricity-consuming products is enhanced.

Description

technical field [0001] The invention relates to the technical field of electrical appliances, in particular to a ground wire safety voltage control system. Background technique [0002] In real life, the live conductors in the electrical circuit of electrical products - the short circuit between the zero line and the live line, the earth, the electrical equipment shell, various grounded metal pipes or other conductors, or when the insulation resistance of the conductor to the ground is less than the specified value A ground failure may occur, and the ground failure will cause an overcurrent, which may cause a risk of fire or electric shock. In order to avoid this risk, a leakage protection plug to prevent the ground failure is widely used. [0003] The leakage protection plug is installed between the power supply and the load, and its function is to sense whether there is a leakage current through the transformer on the neutral wire, the live wire or the transformer on the g...

AI Technical Summary

Problems solved by technology

[0004] The existing leakage protection plug can trip and cut off the power only when the transformer of the neutral wire, the live wire or the transformer of the ground wire detects a leakage current signal, and the leakage current is generated based on the earth. If there is no connection to the ground, the power cannot be cut off if the transformer on the neutral line, the live line or the transformer on the ground line does not detect the leakage current signal. Electrical appliances leak electricity, and current flows into the ground wire to make the ground wire electrified, which will pose a threat to the personal safety of users

[0005] In actual use, if the ground terminal of the power socket is not grounded, and the electrical appliance is not grounded, when the ground wire is charged or the electrical appliance leaks, the charged body cannot generate leakage current with the earth, that is, the transformer or ground wire of the neutral wire and the live wire cannot be connected. If the leakage current signal is induced in the current transformer, it will not be able to trip and cut off the power immediately when the ground wire or the electrical appliance is charged. , live wire transformer or ground wire transformer can detect the leakage current signal, and the leakage protection plug can trip and cut off the power at this time. It can be seen that the electric shock accident of the user has been caused before the power is cut off.

[0006] In addition, if the user's home power system adopts the TN-C-S system (connecting to zero protection system), the connection line from the neutral line of the circuit to the zero pole in the socket fails, and when the neutral line of the power supply is missing, the current in the electrical load Flow from the live wire to the grounding point of the electrical appliance, so that the ground wire is charged; or the neutral wire and the live wire are reversed, and the ground wire is directly charged. At this time, all accessible metal parts are charged, which is very likely to pose a threat to the personal safety of the user.

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