All-around current electrical fire alarm monitor of 400V low-voltage distribution network

Abstract

The invention relates to an all-around current electrical fire alarm monitor of a 400V low-voltage distribution network, comprising air switches arranged on A, B and C phase lines and a current transformer arranged on each phase line in sequence; a residual current transformer is arranged on the A, the B, the C and an N phase lines together; residual current and the A, the B, the C and the N phase lines are respectively connected with a current detector; arc light impact current can be generated by the electric discharge phenomena between fire wires and between a fire wire and a zero line andthe electric discharge phenomenon due to poor contact of the same phase; and the phenomena can be monitored by monitoring the three-phase current incremental quantity. The invention has the benefits of overcoming the defects that electric arc can be caused by discharge due to the insulated damage between wires (including between phases and between the fire wire and the zero line) and poor field wiring contact and cannot be detected by the residual current detector.

Description

Technical field: [0001] The present invention mainly relates to a current electric fire alarm system, in particular to an electric fire alarm system which is caused by electric arc due to electric arc caused by insulation damage between lines (including phase to phase, live wire and neutral line) and poor connection of on-site wiring. Background technique: [0002] At present, the relevant technical specifications of building electrical fire alarms in my country only require the detection of leakage current and overcurrent (except for temperature). This standard and its products have a better detection and early warning effect on fires caused by grounding insulation damage. However, the mechanism of most of the faults is caused by the insulation damage between the line and the line (including phase and phase, live wire and neutral wire) and the discharge caused by the poor contact of the field wiring. These discharge dangerous situations cannot be detected by the residual cu...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is to overcome the disadvantages that the ordinary residual current monitor cannot detect the damage of the insulation between the wires (including the phase and the phase, the live wire and the neutral wire) and the electric arc caused by the discharge caused by the poor contact of the on-site wiring. Above technical problem, the main technical characteristics of the present invention are as follows: mainly collected A, B, C, three-phase current, realize the monitoring arc discharge phenomenon and reach the purpose of electrical fire alarm by compound criterion, it is characterized in the following steps:

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