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Causes of Electric Motor Burning by Water pump

1. First, find out whether the motor burns the bearing (mechanical fault) or the coil (electrical fault). If it is the fault of burning coil, it is mainly caused by overcurrent, sometimes too high or too low voltage will also cause the coil to heat and short circuit, so check that the voltage when running is too different from the rated voltage.There may be several reasons for over-current short-circuiting: A. the equipment is overloaded to make the motor run for a long time at rated or over rated current. In particular, the starting current of the motor is 3-5 times that of the rated current. Therefore, we should try to avoid running with load or full load when starting the equipment (mainly depending on the matching allowance of rated current and normal operating current of motor). B, the motor works in a wet working environment. The insulation of the coils should be checked before the motor starts. The insulation requirements of different voltage grades are also different. May r...
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Water pump selection in HVAC system

1,Chilled water pump: a device that drives the circulation of water in a chilled water loop. The end of an air conditioning room (such as a fan coil unit, an air handling unit, etc.) requires cold water from the chiller. However, refrigerated water does not flow naturally due to the limitation of resistance, which requires the pump to drive the cooling water for circulation to achieve the purpose of heat transfer. 2,The cooling water pump in cooling water loop drive water device for circulating cooling water. As we know, take part in the refrigerant heat chiller, cooling tower and flows into the heat release. The cooling water pump is responsible for driving the cooling water circulating in the cooling tower and the unit closed loop shape. With the chilled water pump. 3,Feeding water pump: air conditioning water supply device, responsible for the treatment of soft water into the system. The commonly used pumps are horizontal centrifugal pumps and vertical centrifugal pumps, which can ...

Introduction of Jiangxi Gelaili Pump industry co.,ltd

About the Company JiangXi New Rui Hong pump industry co.,ltd was established in1973, we are focus on researching,producing and exploring in pumps. it is a province level advanced manufacturer, also have advanced quality management system and producing process. The company have more than 300 workers,30 of them are high technical engineers.The output is over 100 milion CNY per year.Our pumps are widely used in a lot of area and industry,such us building construction, irrigation and water conservancy, metallurgical and mine exploring,textile and chemical technology,food area,shipping,air-conditioner,fire control equipment,resident water supply and so on. JiangXi Gelaili pump industry co.,ltd is belonging to JiangXi New Rui Hong group.For enterprise development we establish a new working area in Ducheng industry area for higher technical pumps.we have more than 200,000 square meters manufacture area,and advanced process equipments,automatic process center,we also have over 500 sets te...

How to exclude the interference from the frequency converter

These problems often occur when you work at regular work and debug the equipment: 1 . When the converter of the heat exchange station is opened , the pressure transmitter shall jump ; 2 . using frequency converter to control the water supply , the voltage transformer is used as a signal for collecting pressure , and the voltage transformer is interfered by the frequency converter ; 3 . When the frequency converter starts up the motor , the voltage change signal is unstable and the jitter is great ; 4 . The voltage transformer ( 4 – 20mA ) shall jump after the frequency converter is started , and the integrated thermal resistance ( 4 – 20mA ) nearby is not affected , and the signal line is not shielded . These phenomena are due to the interference of the frequency converter. Why does the inverter produce interference The inverter comprises a rectifying circuit and an inverter circuit , wherein the input AC power is converted into a DC voltage through a rectifying circuit and a wave loo...

What are the ways of Motor protection ?

1. Overload protection When the motor runs over the rated current for a long time under the overloaded fault, it will cause the motor to overheat, reduce the insulation and burn down. The protector calculates the thermal capacity of the motor according to the heating characteristics of the motor. The characteristics of different tripping levels corresponding to the protection of the motor by simulating the heating characteristics of the motor and the overload protection. 2 . Underload protection When the load of the motor is the pump type load , the motor no – load or under – load transfer is harmful , the protector provides under – load protection , and when the percentage of the average current of the three – phase and the rated current is lower than the set value , the protector shall operate within the action ( delay ) setting time or alarm within the alarm time . 3, blocking / blocking protection When the motor is starting or running, if the electric timing shaft is jammed be...

Pressure fluctuation propagation of a pump turbine at pump mode under low head condition

Pressure fluctuation at the vaneless space and vanes passages is one of the most important problems for the stable operation of a pump turbine. The fluctuation appears in any operating condition. Much research has been done on the pressure fluctuation of hydraulic machinery. However, the details of pressure fluctuation propagation of the pump turbine at the pump mode have not been revealed. The modern pump turbine with high water head requires the runner to be “flat”, which would induce pressure fluctuation more easily than the low head pump turbine. In this article, a high head pump turbine model is used as the research object. As the pressure fluctuation at off-design point is more serious than at the design point, the low head condition is chosen as the research condition. Pressure fluctuation at the vaneless space and vanes passages is predicted by the computational fluid dynamics method based on k- shear stress transport model. The experiment conducted on the test rig of the Har...

How to take advantage of basement

The drainage design of the basement of the building is an important part of the whole building drainage design . The basement not only has equipment room ( including substation , air - conditioning room , water pump house , etc . ) , and many other basement is usually used as a garage during wartime as a protection unit . Because of the lower elevation of the basement of the building , the drainage of the basement can not be discharged to the municipal pipe network by gravity . Generally , the basement is provided with a drainage and drainage system . The drainage means that the water infiltrated into the basement is introduced into the water collecting well through the intercepting ditch , and the water is discharged to the outdoor municipal drainage channel by a water pump . The type of drainage in the basement of the building , the drainage of the basement of the building is roughly divided into the following types : 1. Domestic sewage. The sewage produced by the basement toilet,...