The variable working conditions for both high and low pressure sides of an N-38000 type dual-pressure condenser was calculated

when this condenser was in single and dual water circulating pump operation

at different steam loads and cooling water inlet temperatures.On this basis

the equivalent heat drop method was applied to calculate the optimal inlet temperature of circulating water for suitching the single and dual circulating water pump

at different unit loads.The results show that

with the unit load of 40%

running single circulating water pump is more economical

while when the unit load is 60%

80% and 100%

the optimal inlet temperature of circulating water is 25.1℃

22.3℃ and 17.6℃

respectively.