Ground wire electrification protection circuit, method and air conditioner with the circuit

Abstract

The invention discloses a ground wire live protection circuit and method and an air conditioner provided with the circuit. The ground wire live protection circuit comprises a first detection circuit (A) for detecting current in a ground wire, a relay (B), a driving circuit (C) and a microprocessor (D), wherein the first end of the relay (B) is connected with a zero wire, and the second end of the relay (B) is connected with the ground wire; the driving circuit (C) is connected with the third end of the relay (B) and used for driving the relay (B) to pull in; and the microprocessor (D) is connected between the first detection circuit (A) and the driving circuit (C) and is used for judging whether the current in the ground wire is larger than a preset current value and controlling the driving circuit (C) to drive the relay (B) to pull in to enable the ground wire and the zero wire to be connected when the current in the ground wire is larger than the preset current value. According to the ground wire live protection circuit and method and the air conditioner provided with the circuit, the current flowing through the ground wire of an electric appliance can be detected in real time; once the current value exceeds the safety current value of the human body, the ground wire and the zero wire in the circuit are connected, and therefore the safety accident, namely electric shock of the human body, is avoided.

Description

technical field [0001] The invention relates to the field of electrical appliances, in particular to a ground wire electrification protection circuit, a method and an air conditioner provided with the circuit. Background technique [0002] Class I electrical appliances such as household air conditioners are mandatory grounding. The basic principle of grounding protection is to clamp the ground voltage of the leakage part within a certain range through the clamping effect of the grounding resistance, so as to avoid excessive current passing through the human body to the ground and cause damage to the ground. Accidents that cause harm to the human body or even cause death by electric shock. [0003] The basic principles of ground protection are described as follows: [0004] Assume that the rated operating voltage of an electric heating product with a metal casing is V, and the equivalent internal resistance of the circuit is Rj. Under normal circumstances, the metal shell i...

AI Technical Summary

Problems solved by technology

[0010] The main purpose of the present invention is to provide a ground wire live protection circuit, a method and an air conditioner with the circuit, so as to solve the problem that the human body is easy to get an electric shock when the ground wire of the electrical appliance is charged.

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