Many Thanks NereusNereus wrote:Jimmy:
The graph that is shown on the link is flow versus total "head", it is not showing pressure.
The model number of the pump (150, 200 etc up to 400), is the wattage rating of the motor. 746 Watts is equal to 1hp, so the 400 model is just over 0.5 hp.
The vertical bar of the graph is showing the "head" that the various model pumps can "push" against. The "head" has to be calculated, and is a lot more than just the vertical height of where the water has to be pumped. It includes the vertical height but much more important is what is referred to as "friction head". Each pipe fitting, change of direction, restriction, reduction in pipe size, actual pipe size, adds to the "total head". The graph shows a "total" theoretical head of 12 metres.
The horizontal bar is showing the the flow in litres per minute. The colored lines of the graph are a plot of how many litres per minute will flow against a corresponding total head. Note that at the total maximum head of 12 metres there is zero flow.
Any quality shower head should show the flow rate at a given pressure.
You may find that it is worth the extra cost of going up a size with your pump selection: ie, 350 Model. If the buildibg is still at the stage where you can change it, I would try to have the pipe size increased, especialy the section that is feeding the upstairs part of the house, even to the extent of having a seperate run of larger size feeder pipe installed.
Hope that is of some use to you.
I now understand the graph and will take into consideration your comments before purchasing.
Cheers