Put into trip
1) The three-phase power line, including the neutral line, does not pass through the zero sequence current transformer in the same direction, just correct the wiring.
2) There is an electrical connection between the circuit with the leakage circuit breaker installed and the circuit without the leakage circuit breaker installed, and the two circuits can be separated.
3) There are loads of one fire and one ground in the line, and it is enough to eliminate such loads.
4) The working neutral line passing through the zero sequence current transformer has repeated grounding, and repeated grounding should be eliminated.
5) The leakage circuit breaker itself is faulty and should be replaced.
Malfunction
1. Caused by overvoltage. For example, the circuit breaker can be activated when an operating overvoltage occurs in the line. At this time, a delay or impulse voltage non-acting leakage circuit breaker can be selected, or a resistance-capacitance absorption circuit can be installed between the contacts to suppress the overvoltage. Overvoltage absorbing device is put into the line.
2. Electromagnetic interference. If there are magnetic equipment or high-power electrical equipment nearby, the installation position of the leakage circuit breaker should be adjusted to keep away from such electrical components.
3. Circulation influence. If two transformers are operated in parallel, they have their own grounding. Because the impedances of the two transformers cannot be completely equal, this will generate circulating current in the grounding wire and cause the circuit breaker to operate. Just remove one grounding wire. In addition, the same transformer supplies power to the same load through two parallel circuits, and the currents in the two circuits may not be exactly the same, and there may be circulating currents. Therefore, the two circuits should be operated separately.
4. The insulation resistance of the working neutral wire is reduced. When the insulation resistance of the working neutral wire is reduced, if the three-phase load is unbalanced, a relatively large working current will appear on the neutral wire and flow to other branches through the ground, so that leakage current can appear on each leakage circuit breaker , Make the circuit breaker malfunction.
5. Improper grounding. If the neutral wire is repeatedly grounded, it will cause the leakage circuit breaker to malfunction.
6. The influence of overload or short circuit. If the leakage circuit breaker has short-circuit protection and over-current protection at the same time, a malfunction will occur when the setting current of the over-current protection trip unit is not appropriate. At this time, adjust the setting current value.
Company Profile
Changan Group Co., Ltd. is a power manufacturer and exporter ofindutrial electrical equipment.We are committed to improving the quality of life and the environment through a professional R&D team, advanced management and effective services.
Tel: 0086-577-62763666 62780116
Fax: 0086-577-62774090
E-mail: sales@changangroup.com.cn
Post time: Nov-20-2020