HYDRAULIC SYSTEM OPERATION Continued
Always set the high pressure relief valve at a higher pressure (150
PSI higher) than the pump compensator pressure - DO NOT use
the relief valve to regulate the test stand output pressure.
Adjust the system relief valve to relieve the system pressure at 150 psi above the pressure required for
test. Refer to the applicable aircraft technical manual to determine the required pressure for testing.
(Example: 800 psi test pressure, set the system relief valve at 950 psi on the system pressure gage.
Turn the system relief valve adjusting screw clockwise until 950 psi shows on the system pressure
gage. Lock the adjustment screw with the locknut.)
Open the compensator shutoff valve, turn handle counterclockwise. Adjust the system pressure with the
pressure compensator until the system pressure gage indicates a pressure slightly higher (50 psi
higher) than the maximum pressure required for test.
(Example: 800 psi test pressure, set system pressure with the pressure compensator, turn screw knob,
clockwise until 850 psi is indicated on the system pressure gage. Lock the control with the locknut
under the knob.)