Pump-specific load motors have horizontal and vertical structure of two applications, with three major technical features: a relatively small starting torque, relatively few start-up frequency, continuous operation time is relatively long.
Pump motor is usually the majority of squirrel cage rotor asynchronous motor or synchronous motor, the motor power is greater than the shaft power of a grade, and the choice of motor poles and pump head, the flow is closely related. Such as shaft power of 22kW, select 30kW motor; 2-pole motor is generally used in high lift, flow is not big case; large flow, small lift 4-pole motor can choose the occasion; large flow, lower head to choose 4 or 6 pole Motor.
Depending on the application of the scope of application of places and economic factors, etc., pump and motor connection in the following ways:
● pump shaft and motor shaft directly connected;
● The pump shaft is connected to the motor shaft through the coupling.
● The pump shaft is connected with the motor shaft through the gear box;
● The pump shaft is connected to the motor shaft via a hydrodynamic coupling.
Pump motor load size and pump head and flow related. High-lift pump work in the high-lift point of its flow is the design point of flow in the low-lift work, the equivalent of the pump outlet resistance decreases, then the centrifugal pump flow will increase, the pump motor overload , Beyond a certain extent will burn the pump motor.
Motor over-current prevention
● Avoid overloading the equipment and make the pump motor operate at rated current or over-rated current for a long time. Because the pump motor starting current is 3-5 times the rated current, so pay special attention to avoid loading or full load to start the device.
● pump motor in a more humid working environment. The pump motor should be checked before starting the insulation and insulation phase to the ground, in the operation of the pump motor should be noted that the pump motor waterproof moisture.
● Strengthen the maintenance, reduce pump mechanical overload caused by the pump motor overload
Real-time monitoring of the pump motor winding temperature, cooling and cooling system failure to avoid burn-in accident. General pump motor coils are used air-cooled shell, submersible pump is water-cooled shell. Large pump motors use air-to-air heat exchanger, air-water heat exchanger cooling. If you cut off the cooling medium, so that the coil can not heat, may burn the coil.