Chris, thanks for the feedback and the work you did.
I sense a contradiction in this statement;
[Our pumps come with the lowest of three fixed TRV values. The set-point is 2,500 psi, thus the statement "approximately 100-140 bar (1500-2000 psi) above the system relief valve pressure" still holds true.]
I see two interpretations.
1… The TRV “setpoint is 2,500 psi”, presumably referenced to reservoir pressure, which is ambient cabin pressure assuming the reservoir is well vented. Thus the TRV will limit the output pressure to 2,500 psig max. In that case the graphs in the brochure do not apply for our pumps above 2500 psi.
2… The TRV setpoint is “(1500-2000 psi) above the system relief valve pressure.” I interpret “system relief valve pressure” to be the setpoint of the internal HPRV or LPRV located upstream of the check valves. These set points are not specified in the brochure, but the performance graphs indicate that the HPRV is at least 3,000 psi which would make the TRV setpoint 4,500 - 5,000 psig.
Perhaps you are saying the TRV setpoint is 1,500 – 2,000 psi above the pressure switch setpoint’s, but I was commenting on this quote from the brochure which says something else.
“It is a fixed relief valve with a pressure setting approximately 100-140 bar (1500-2000 psi) above the system relief valve pressure.”
If the TRV setpoint is lower than the HPRV and LPRV setpoints I see no need for the HPRV and LPRV. What is their purpose?
I would like to know how much pressure it takes to keep the wheels in the wells during a high speed high G pullup. If the relief valve lifts and the gear comes out of the wells, it could literally blow the doors off the airplane. If anybody with gauges does a gear test in the next few months, please note the pressure just before the gear tightens up in the wells and let me know. Five times that number should be about right.