Analysis of Motor Overload in Selecting Chilled Water Pump

Through analyzing the problem of chilled water pump motor overload in designing HVAC system, the paper elaborated hazards of pump motor overload. Combining with practical examples, based on two factors(pipe network characteristic curve and pump performance curve) of actual operating point of pump, the calculation method for checking the pump motor overload is proposed, when chilled water pumps operating in parallel reduced, the actual water flow of chilled water pumps showed a gradual increasing trend, that leads to the chilled water pump motor power growing, even more than the rated motor power.Based on the reason for the pump motor overload, problems that need attention in designing HVAC system are noted.