Pump power consumption issue
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Dear experts, the problem is described as follows: I choose a pump; if the calculated power is 6 kW (shaft power), then the pump should be selected with a capacity of 7.5 kW. Question: Is the power consumption of this pump 7.5 kW when it is operating under actual conditions? ?Or 6kw?
Because electric motors also have an efficiency factor, and couplings have their own transmission efficiency as well; the total power consumption should be the shaft power divided by these efficiency factors. The actual power consumption is therefore higher than the shaft power
It should actually be greater than 6 kW (shaft power); 7.5 kW is used as a reference value
You are asking about the motor’s input power, which is the power supplied to the motor by the power source. Generally, it can be calculated by dividing the shaft power by the motor efficiency (ignoring the coupling efficiency); this value is roughly equal to the motor’s input power, which represents the actual amount of electricity consumed. A motor power of 7.5 kW means that the maximum output power of the motor is 7.5 kW, while the actual input power (power consumed by the power supply) is greater than 7.5 kW.