Anti-shake applied electric AC Contactor Selection

1, the voltage drop type "shake" (voltage drops below a certain value): "shake" long duration (generally less than 2 seconds), the voltage drops below 70% of rated contactor tripping. At this time, the motor power decreases, the rotational speed starts to decrease, but the role of inertia, the speed does not drop significantly, the voltage is restored, the motor current through the punch after a mcb circuit breaker to a value, see a curved, In this case the motor power supply system should be maintained, that contacts should not trip, maintaining the continuity of the production will not be affected. If the "shake" the duration continues to increase, the motor speed quickly to the weary down direction. Therefore, the "shake" the contactor does not trip in less than two seconds better.2, the voltage loss type "shake" (voltage loss, the voltage drops to zero) "shake" of short duration, a large grid system, mcb circuit breaker, voltage drop and recovery curve shown in Figure two different systems, "Akira power "when the voltage waveform is also shown in Figure three different, in the" shake "voltage is restored, the motor current is increased from zero, and the impact of non-periodic component, and then quickly return to the operating values, see a curve, in which case The "shake", the motor current impact of non-periodic component very short time (less than 10 ms), so you can Electric energy meter the impact of the grid, the motor power is not breaking (contactor does not trip), so that the continuity of production is not affected.
 3, "shake" the voltage drops to zero, and the motor speed drops below 30% of rated voltage is restored, the motor current see a curve, then the non-periodic current component impact on the grid will have to consider the impact of Batch start taking manner, the impact on production is inevitable! We think: "shake" the grid voltage drops to 30%, the main circuit should remain on when the voltage is restored the original production status will remain the same! Also confirmed the fact that this solution is feasible. Based on the above we hope to have such a contactor: "shake" come without tripping, "shake" the duration of the motor speed significantly greater than the fall time, the contactor shall trip, start and stop should maintain contact is the original state unchanged! FS series "shake" without tripping contactors meet this requirement!