The current of the centrifugal pump is above the rated value, and the motor is heating up
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The centrifugal pump, whose conveying medium is sodium hypochlorite, has a designed flow rate of 373 m³/h and a head of 35 m. It is equipped with a 90 kW motor, with a rated current of 163 A. The current flow is 265, the operating current is 165A, and the motor temperature reaches up to 70+℃. How should this be resolved? Can the cutting impeller be fixed?
If the head is high, it’s okay; otherwise, it won’t work.
It’s a design flaw; hurry and get the design institute to fix it.
The flow rate is controlled (reduced) using an outlet valve to adjust the current, but this is not a permanent solution; if there is a problem with the pump itself, disassembling it for inspection is the proper approach.
This post was last edited by zwp997 on 2015-7-26 at 17:11. The flow rate does not meet the design requirements, which causes the current to exceed limits and affects the production process. Is it used for wastewater treatment? It’s probably a selection issue; I made the choice based solely on the product manual, without considering the impact of density on motor power, which resulted in choosing a motor that is too small. We can’t keep disassembling the pump every time, right?
It’s not a problem with the pump, but with the motor.
Is it a device that has just been turned on, or one that has been running for some time? …
1. Calculate based on the medium density to see if it is a problem with the motor selection. 2. Is the problem arising after it has been in operation for some time, or is it a new pump? Check whether the density of the medium has increased. 3. Is there a return pipeline, and is the flow rate from that pipeline not included in the 265 value? What is the head pressure when the flow rate reaches 265?
This phenomenon can also occur when the motor gets wet; you might want to check that.
The poster should first figure out what is causing the overcurrent. Start by checking the things that are easy to assess, such as whether the head pressure is too high, whether the flow meter is accurate, whether the specific gravity of the medium was taken into account during selection, and whether there is any diversion of flow after the pump but before the flow meter. If all these factors can be ruled out, then consider whether it is a problem with the pump itself.
Is your flow head not matching the actual value?