Why does the circuit breaker trip after the pump starts?

There are many reasons for this phenomenon. In general, it can be checked from the two aspects of electrical faults and mechanical faults.

Mechanical Failure

First of all, for mechanical reasons, the possibility of bearing oil shortage and impeller being stuck by foreign objects is relatively high. When the bearing is short of oil or the impeller is stuck by foreign objects (such as ropes, stones, etc.), the motor is overloaded and the current rises. cause the circuit breaker to trip.

Secondly, it is also possible that the submersible pump is not completely covered by the water because the water is too shallow. If the submersible pump is not covered by water, it will not get good heat dissipation, the motor temperature will rise, and it may also cause a trip.

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Electrical Fault

1. Turn-to-turn short circuit

When the insulation of the motor coil is damaged, it may cause a short circuit between turns (a part of the coil is shorted). Turn-to-turn shorts shorten the effective length of the coil, drop the impedance, and increase the current, thereby tripping the circuit breaker.

2. The power cord is too long

If the power line is too long and the line resistance is large, there will be more voltage drop. That is, although the voltage of the switch terminal is normal, the voltage to the submersible pump is not enough. If the motor voltage is insufficient, then the current will rise, which will also cause a trip.

3. Insufficient capacitance

If it is a water pump that was used normally before, and it trips after a period of use, it may also be that the capacitance of the water pump is too small. If the capacitance is too small, the phase between the main and auxiliary windings of the motor will change, and the rotational force and speed of the motor will decrease, resulting in insufficient power and increased current.

4. The circuit breaker is too small

If the rated current of the circuit breaker is too small, when the pump runs for a period of time, the switch will trip due to overload(https://en.wikipedia.org/wiki/Overload). When choosing a circuit breaker, it must be ensured that the rated current of the circuit breaker is greater than the actual current of the water pump, and a high-quality and reliable circuit breaker should be selected,such as circuit breaker of CSQ. Rich manufacturing experience, complete product line, complete certificate report.More reasonable configuration, more reliable quality.

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