The range of the ΔPsw is normally within 0.02-0.05MPa. This means that with different pressure Pc and Ps the switch control differential pressure ΔPsw has to be changed. This will obviously increase the complication of the control system. So for simplicity and lower cost, we intend to select a determined value for the ΔPsw. For reclaiming more energy, we expect to select a smaller set value of ΔPsw. But it would not satisfy the velocity requirement with a higher supply pressure Ps or higher pressure Pc in receiver.