Leakage protection circuit breaker with small current fault protection between phase lines

Abstract

A leakage protection circuit breaker includes an inter-phase leakage current protection component. The inter-phase leakage current protection component includes: a first current transformer (CT1), including a first coil (CT1‑N1) with N1 turns, and a first coil (CT1‑N1) with N3 turns. The third coil (CT1‑N3) and the fifth coil (CT1‑N5) with N5 turns for driving, the first coil is connected in series at the input end of the first phase line (L1); the second current mutual inductance The device (CT2) includes a second coil (CT2‑N2) with N2 turns and a fourth coil (CT2‑N4) with N4 turns. The second coil is connected in series in the first phase line (L1). Close to the load; the protective relay (RLY) operates based on the current of the fifth coil (CT1-N5) and disconnects each phase line (L1, L2); among them, the first current transformer (CT1) The third coil (CT1-N3) and the fourth coil (CT2-N4) of the second current transformer (CT2) are connected in series to form a closed loop, where N1=N2 and N3=N4.

Description

technical field [0001] The invention relates to a leakage protection circuit breaker. Specifically, it relates to a leakage protection circuit breaker with phase-to-phase small current fault protection. Background technique [0002] The traditional leakage protection circuit breaker protects against personal electric shock or electrified equipment shell. Usually, personal electric shock or equipment shell is charged when the human body or equipment shell touches the single-phase phase line. The electric shock current passes through the phase line- The human body / or shell-earth forms a loop, causing damage to the human body / equipment. The traditional leakage protection circuit breaker uses the residual current of the system to react and act on the leakage current between the phase line and the earth. During normal operation, the residual current of the system is almost zero, so its action setting value can be set very small (generally mA level), when the system has a person...

AI Technical Summary

Problems solved by technology

[0003] However, traditional leakage protection circuit breakers lack protection against small leakage currents caused by human body, equipment, etc. contacting between phase lines.

The cause of the electric shock between the human body and equipment between the phase wires may be the deterioration of the insulation between the phase wires, which will also cause personal injury or even death, damage to equipment, and may cause a fire

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