IMFMLSOL--independent control strategy with open
loop flow rate control and flow matching pump control.
Aiming to verify the operation of the gate valve, this work implemented an open
loop flow control system; the analog aperture signal comes from a PLC.
Meanwhile, the pressure drop upstream of the pressure sensor is proportional to the loop water flow rate [Q.sub.loop] squared and is equal to the design system pressure drop [H.sub.d] minus the pressure drop downstream of the pressure sensor at the design
loop flow rate [Q.sub.loop] d if all cooling coils are located upstream of the pressure sensor.
The Aa2 reflects the system's near monopoly in a robust service area that includes the City of Houston (Aa2 negative), and the system's strong balance sheet that benefits from a closed
loop flow of funds.
But an additional 50% energy saving has now been achieved by applying closed
loop flow control, using water temperature as the control variable.
A closed
loop flow control system automatically adjusts motor speed as a filter becomes full, so the extraction rate remains constant.
The highly automated System II features closed
loop flow controls and variable frequency pump drive motors, said to allow the operator to digitally set the output rate without wet calibration.
Note that the hot-water
loop flow rate has a minimum (100 gpm [6.3 L/s]), due to the minimum speed limit (60% of the full speed) of the hot-water circulation pump.