Hi,
Im trying to figure out the specs of a Laing D5 pump and it feels like ive been eating crazy-pills...

EK waterblocks write about their Laing D5 pump:

Maximum head: 10 ft (3.1 m)
Maximum discharge: ~ 317 GPH (1200 LPH)
Connection size: 1/2" barbs
Maximum pressure: 50 PSI (3.5 BAR)

Using the formula for pressure head at http://en.wikipedia.org/wiki/Pressure_head the maximum pressure should only be 3.1 Bar if the 3.1 meter is correct. Maybe just a small error but nevermind...

Skinneelabs writes ( http://skinneelabs.com/laing-d5-top-comparison/ ) on the y-axis: "Total dynamic head pressure".

Using the formula for dynamic pressure at http://en.wikipedia.org/wiki/Dynamic_pressure it shows that when the velocity of the fluid is 0 m/s then the dynamic pressure is 0 m/s. Their graphs show otherwise.

Okay, so lets assume that the pressure is 50 psi and the pressure head is approx. 3.5 meters.

Extremesystem writes ( http://www.xtremesystems.org/forum [...] s-the-same ) that the maximum pressure at flowrate 0 is approx 5.5 psi. About one tenth of what it should be.

What is right and what is wrong?