Agilent Technologies 1200 Series Reference Manual page 88

3 Troubleshooting and Test Functions
Ramp 1:
After initialization, plunger 2 is at the top of its stroke. The test begins with
plungerplunger 1 delivering with a stroke length of 100µl and a flow of
153µl/min. The plunger sequence during the pressure ramp is 1-2-1-2. The
pressure increase during this phase should be linear. Pressure disturbances
during this phase indicate larger leaks or defective pump components.
Plateau 1:
plunger 2 continues to pump with a flow rate of 2µl/min for approximately
one minute. The pressure during the plateau should remain constant or
increase slightly. A falling pressure indicates a leak of >2µl/min.
Ramp 2:
The flow is changed to 153µl/min, and plunger 2 continues to deliver for the
rest of its stroke. Then plunger 1 continues to pump to complete the second
half of the ramp.
Plateau 2:
The flow is reduced to 2 µl/min for approximately one minute (plunger 1 still
delivering). The pressure during the plateau should remain constant or
increase slightly. A falling pressure indicates a leak of >2 µl/min.
Ramp 3:
The flow increases to 220µl/min and the stroke is changed to 100 µl. Plunger 1
completes its stroke. Next, the flow is changed to 510µl/min. The ramp reaches
390 bar with the plunger sequence 2-1-2-1.
Ramp 4:
When the system pressure reaches 390 bar, the flow is reduced to zero, and the
pressure stabilizes just below 400 bar.
Plateau 3:
1 min after reaching the maximum pressure, the pressure drop should not
exceed 2 bar/min.
88 1200 Series QP Reference Manual