Full-function secure plug

Abstract

The related all-purpose safe plug comprises: three poles every with switch; between phase and zero line, a zero-sequence current transformer, a test loop, an amplification circuit, a dc power, and a release device; a ground line connected by a movable contact spring and a fixed point; another zero-sequence current transformer in the ground line with secondary output end paralleled with another amplification circuit whose output serial connects with the trigger electrode of a thyristor. This invention can prevent electrification of three phase lines and over-temperature of plug self.

Description

technical field [0001] The invention relates to a power plug, in particular to an all-round safety plug capable of carrying fireproof wires, neutral wires, and ground wires and preventing overheating. Background technique [0002] An all-round leakage protection plug disclosed in the Chinese patent document CN1142618C is provided with a live detection sensor for the ground wire in the ground wire of the power line, and a zero-sequence current transformer is provided between the phase and neutral wires, and the phase and neutral wires inside the plug are 1. There is a pair of contacts between the ground wire and the breaker, and a spring is connected between the upper end of the breaker and the copper reed of the ground wire moving contact, so that there is always a spring force for the pair of ground wire contacts to attract each other. When the release operates, the ground wire is connected first, then the phase and neutral wires are connected, or the phase and neutral wire...

AI Technical Summary

Problems solved by technology

[0002] An all-round leakage protection plug disclosed in the Chinese patent document CN1142618C is provided with a live detection sensor for the ground wire in the ground wire of the power line, and a zero-sequence current transformer is provided between the phase and neutral wires, and the phase and neutral wires inside the plug are 1. There is a pair of contacts between the ground wire and the breaker, and a spring is connected between the upper end of the breaker and the copper reed of the ground wire moving contact, so that there is always a spring force for the pair of ground wire contacts to attract each other. When the release operates, the ground wire is connected first, then the phase and neutral wires are connected, or the phase and neutral wires are disconnected first, and the ground wire is disconnected last, so as to meet the requirements of safe electricity use, but there are the following disadvantages: 1. Phase, neutral wire When the zero-sequence mutual inductance coil of the ground wire fails, such as broken wire, etc., the zero-sequence mutual inductance coil of the ground wire cannot work, so it cannot achieve the purpose of cutting off the ground wire in time when it is charged.

2. Since the zero-sequence mutual induction coil on the ground wire and the zero-sequence mutual induction coil on the phase line and zero line are connected to the input terminal of the same amplifier, the output voltage of the zero-sequence mutual induction coil on the ground wire is affected, thereby affecting the ground The operating current of the ground wire makes the operating current when the ground wire leaks electricity exceed the safe current that the human body can bear, so it cannot play a protective role and will still endanger human life.

3. The zero-sequence mutual inductance coil on the ground wire in this circuit is greatly affected by temperature, and its operating current will change drastically with temperature changes, so it cannot adapt to different use environments

4. It uses the so-called two chambers to prevent overheating of the plug, which cannot effectively prevent overheating.

[0003] The Chinese patent document CN2609228 Y which I applied for discloses a safety plug for anti-ground wire electrification. It adopts a different tripping mechanism and a mechanism for preventing overheating from the aforementioned patent document. Although the safety is improved, the ground wire The same amplifier is still used for the zero-sequence tripping coils of the phase and neutral wires, so there are still disadvantages similar to the above-mentioned patents, and the safety is not high enough

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