Why does the water pump always shut down due to overcurrent protection during testing? What is the reason?
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It is a double-suction turbine type with a flow rate of 700 m3/h, a head of 70 m, and a power output of 140 KW. During testing, it keeps shutting down immediately upon startup. The inlet valve is fully open and the outlet valve is fully closed; there are no issues with the motor or the equipment. The pipe diameter at the equipment’s inlet, which is DN400, cannot possibly be blocked
Axial flow pumps should be started with the valve open; starting them with the valve closed results in excessive shaft power. You can see this by looking at the pump’s performance curve
Is there an issue with the setting of the protection current value for the motor? When testing the newly installed pump, it also stopped working as soon as it was turned on; the problem was resolved by increasing the protection current value
Won’t starting by opening the valve cause too high a current? The instantaneous current
A soft start was designed, but the system still trips after some time. Could this be related to the outlet being pressed lower during driving compared to when it’s in normal operation?
The process-related factors can probably be ruled out; we should look for the causes in the motor, wiring, and the protection settings of the electrical cabinet
That won’t happen; trust science – the shaft power required to start an axial flow pump with the valve closed is very high
Could it be that the back pressure at the outlet during the testing process was lower than under normal operating conditions?
That’s not right; this isn’t an axial flow pump at all
Hey, what is the medium that this pump is used to transport? For pumping water at a rate of 700 cubic meters per 70 meters, the effective power is 133 kW; if the shaft power is 140 kW, then the efficiency of the pump is 95%. Which brand of pump has extremely high efficiency?