No, I didn,t mix up the two, my spreadsheet (and graph) is dynamic and changes as long as you replicate (by inputting the speed) that the VSD will need to output at the CHANGING flow requirements for any given setpoint (SP) head.
If you set the VSD speed to give you just the desired static head (height) then the top floor will have zero flow, if the building height is say 40 ft or 17 psi you must then add on the required pressure required by the resident say 30 psi so the pump head must be 47 psi, say 50, so the top floor resident will have 30 psi available at his taps/shower and the bottom floor resident will have 50 psi available, pipe friction losses must also be taken into account so IMO the correct way to run this set up is to run on pressure set point and maybe also use some logic to start/stop the VSD when demand is zero but VSD is primarily designed for a constant varying demand. however, yes, you can pick and set a sweet point speed based on the "average" flow demand and start/stop the pump using the pressure transducer or simply installing a pressure switch, all very very interesting.
I have also modified the spreadsheet to give a little more info, it graphically now shows the pump+motor efficiencies, just use the flow (x axis) as the reference, the efficiency will be directly above it, on the red trend.
