Analysis of Causes to Burnout of Centrifugal Pump Pump Motor

Centrifugal pump burning motor mainly has the following reasons:

Starting with a load can cause damage to the motor. The actual use of the head is lower than the head of the pump nameplate; the submersible pump has a long working time without water.

First of all, first find out if the motor burns the bearing (mechanical fault) or burns the coil (electrical fault).

If it is the failure of the firing coil, it is mainly caused by overcurrent. Sometimes the voltage is too high or too low can cause the coil to generate a short circuit. Therefore, first check whether the voltage during operation is not too different from the rated voltage.

Over-current short circuit may have the following reasons:

1. The equipment is overloaded to operate the motor for a long time at rated current or over-rated current. Special attention should be paid to the fact that the starting current of the motor is 3-5 times the rated current, so it should be avoided when starting the equipment with a load or full load operation (mainly depends on the matching margin between the rated current and the normal operating current of the motor).

2. The motor works in a humid working environment. Before the motor starts, the insulation and phase insulation of the coils should be checked. The insulation requirements for different voltage grades are also different and can be checked with reference to relevant national standards. In the operation of the motor should pay attention to the motor's waterproof moisture.

3, mechanical failure of the pump caused by the motor overload, the current is too large and burn the coil.

4, motor heat problem. Pipeline pumps, self-priming pumps, and centrifugal pump motor coils are all air-cooled and the submersible pumps are water-cooled.

For example, the head of the centrifugal pump is used to overcome the height and resistance. When the high-lift pump is working at a high lift point, his flow is the design point flow. If the pump is working at a low head, it is equivalent to a reduction in the pump's output resistance. At this time, the flow of the centrifugal pump will increase, and the motor will be overloaded, and the motor will be burned if it exceeds a certain level. For example, a feed pump has a head of 50 meters and a flow rate of 50 cubic meters/hour. When it feeds water at a height of 50 meters, its flow rate is 50 cubic meters/hour. When it feeds water to a height of 40 meters, Its height and resistance reduce its flow rate to 80-90 cubic meters per hour or more, at which time the motor heats or burns.