Boeing Fuel system operation

[RMC]

Any of you guys willing to elaborate on Boeing fuel pump systems operations. Any thoughts on any of what follows greatly appreciated.
I have always selected centre tank pumps off individually when the time comes (rather than deselect both at exactly the same time).
The EICAS seems to provide some support for this as when a centre pump is selected off there is a second or so delay before the main tank pump indicates delivering pressure.
The non believers are convinced that the 787 EICAS is not a dynamic display and is pictorial only (in this case they are suggesting there is no delay in main tank pump operation, only that the logic in the software is slow to respond).
Along these lines I am also interested in typical fuel line pressures. The manuals say that the centre pumps deliver a higher pressure than main tank pumps (but don’t even give the roughest figures).

[QA1]

I have never worked the 787, so could not respond to your first query, Ref. the second query - hopefully someone who knows what they are talking about will confirm or correct this answer.
Looking at the specs for the Eaton manufactured pumps, the booster pumps appear to be variable frequency 360 - 800Hz, resulting in output pressures dependant on frequency of: min 7psig / max 60psig. The low px warning triggers around 6 to 7psi.
The override / jettison pumps appear to be fixed frequency, the output pressure being dependent on the flow rate - max 53psi at 0 lbs/hr and a min of 17psi at 120,000 lbs/hr, the low px warning triggers around 23psi.
If true, it may go some way to explain why pressure values are not mentioned.

[RMC]

Thanks QA1, interesting that the max pressure of the wing booster pumps is 60 PSIG and max of the override centre pumps is 53 PSIG. Is the low pressure warning you mention connected to the fuel low pressure light (or is it an internal fuel pump trigger to work harder).
obviously this is different for every aircraft type / fuel pipe configuration but what sort of pressure would you typically see in a maximum flow suction feed situation. Would be interested to know what kind of pressure is likely to bring on cavitation.