Tripolar disconnection leakage protection plug

Abstract

The invention provides a tripolar disconnection leakage protection plug, and belongs to the technical field of low-voltage power distribution protection devices. The tripolar disconnection leakage protection plug comprises a tripping circuit, a first zero sequence current transformer, a second zero sequence current transformer and a driving circuit, wherein the driving circuit comprises a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a diode, a thyristor and a driving chip, the seventh pin of the driving chip is connected with one end of a secondary coil of the second zero sequence current transformer, the sixth pin of the driving chip is connected with the other end of the secondary coil of the second zero sequence current transformer through the second resistor, the second pin of the driving chip is connected with one end of the secondary coil of the first zero sequence current transformer, and the first pin of the driving chip is connected with the other end of the secondary coil of the first zero sequence current transformer through the third resistor. The tripolar disconnection leakage protection plug has the advantages that the peripheral devices of the driving chip can be greatly reduced, no action or wrong action can be eliminated, and the use reliability is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of low-voltage power distribution protection devices, and in particular relates to a three-pole disconnect leakage protection plug. Background technique [0002] The three-pole disconnect leakage protection plug is mainly aimed at the poor electricity environment of the user, such as: unreliable ground wire, privately pulled wires, use of drag strips, unreliable power sockets, etc., to provide the function of disconnecting the ground wire when it is live. The existing three-pole disconnect leakage protection plug mainly has two circuit design modes: first, two zero-sequence current transformers are respectively connected to two IC drive circuits, the disadvantage is that the number of electronic components is doubled, and the manufacturing cost is high. At the same time, the failure rate affected by the number of components also increases; secondly, two zero-sequence current transformers are connected to an ...

AI Technical Summary

Problems solved by technology

The existing three-pole disconnect leakage protection plug mainly has two circuit design modes: first, two zero-sequence current transformers are respectively connected to two IC drive circuits, the disadvantage is that the number of electronic components is doubled, and the manufacturing cost is high. At the same time, the failure rate affected by the number of components also increases; secondly, two zero-sequence current transformers are connected to an IC drive circuit in series or in parallel. Defects, such as when the ground wire contains a small amount of non-operating current, and the heating tube of the water heater also produces a small amount of leakage current of the non-operating current, since the two zero-sequence current transformers are connected to the same input port in the IC drive circuit, so they The induced voltage generated will be superimposed or offset, which will cause the leakage protection plug to fail to operate or malfunction.

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