Cause of overcurrent in the DC contactor
Publisher： Apollo / 2021-08-23/ Views：1073
1. Discuss the overcurrent fault of the DC contactor
Overcurrent faults of dc contacters can be divided into acceleration, deceleration and constant speed overcurrent. It will be caused by short acceleration and deceleration time of frequency converter, sudden change of load, unevenly distributed load, output short circuit fault and so on. At this time, we can generally increase the acceleration and deceleration time, reduce the sudden change of load, add energy dissipation braking system components, carry out load dispatch design scheme, and carry out inspection of the route. If the load converter is broken or overcurrent fault, it indicates that the converter rectification circuit is bad, and the converter must be replaced.
2. The main parameters and characteristics of the single-pole DC contactor are introduced in detail
The load of the DC contactor is faulty
Load faults include dc variable frequency load and motor load. It will be caused by too short speed up time, too low working voltage of the power network, too heavy load, etc. Generally, it can increase the speed up time, increase the braking system time, check the working voltage of the power network, etc. The load is too heavy, and the selected motor and frequency converter cannot drag the load, which will also be caused by the poor wetting of the mechanical equipment. For example, the previous one must remove the power of the motor and converter; Such as the latter is to carry out maintenance of manufacturing machinery and equipment.
3. Dc contactor fault summary
1, in other words, in the design, installation, application of frequency converter must follow the specific guidance of frequency converter manual;
2. Electrical design staff and electrical debugging staff on the spot can improve the reference of the frequency converter on the basis of the DC contactor.
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