Relay

Abstract

The invention discloses a relay. The relay comprises a first over-current detection circuit, a second over-current detection circuit, an over-current detection switching circuit, a time delay circuit,an over-current signal processing circuit, an over-current indication circuit and a protection action signal output circuit. When the first over-current detection circuit detects that an over-currentsignal exists in the loop, the over-current indication circuit sends out a first over-current indication signal. After the delay time set by the delay circuit, if the second overcurrent detection circuit still can detect the overcurrent signal, a second overcurrent indication signal is sent out, and the protection action signal output circuit outputs a protection action trigger signal to rear-endalarm action equipment. Therefore, the relay provided by the invention not only can respectively detect the conditions of instantaneous overcurrent and continuous overcurrent, but also can effectively avoid misoperation caused by overcurrent disappearance, and solves the problem of relay misoperation caused by millisecond-level overcurrent or surge existing in a detected loop.

Description

technical field [0001] The invention relates to the field of electrical equipment, in particular to a relay. Background technique [0002] Once an existing relay detects an over-current signal, it locks up immediately, and outputs an alarm and a contact action signal. When there is an overcurrent or surge of mS level in the circuit under test, the relay will send out a protection action signal, which greatly increases the probability of relay misoperation. Contents of the invention [0003] The purpose of the present invention is to provide a relay, which can not only detect instantaneous overcurrent and continuous overcurrent respectively, but also can effectively avoid the malfunction caused by the disappearance of overcurrent, and solve the problem of millisecond-level overcurrent or surge in the circuit under test. Surges cause relay malfunctions. [0004] To achieve the above object, the present invention provides the following scheme: [0005] A relay, comprising:...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a relay, which can not only detect instantaneous overcurrent and continuous overcurrent respectively, but also can effectively avoid the malfunction caused by the disappearance of overcurrent, and solve the problem of millisecond-level overcurrent or surge in the circuit under test. The problem that the surge causes the relay to malfunction

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