Agilent Technologies InfinityLab LC Series User Manual page 119

7 Test Functions and Calibration
Leak Rate Test
Initially, the pressure is increased to about 100 bar below the target pressure,
which has been set for the test.
Then piston 1 is brought to its rear position. An increasing flow is delivered by
piston 1. In case of a leak, the pressure will drop initially as long as the flow rate
delivered by the piston is lower than the leak rate. As soon as the flow rate of the
piston exceeds the leak rate, the measured pressure will increase again.
Therefore the minimum pressure of that curve segment corresponds to the flow
and leak rate at that time and the leak rate is measured. Compare to the
description of the system pressure test
Subsequently, piston 2 is moved to its rear position, then piston 2 delivers and the
measurement is done as described for piston 1.
For a binary pump (G1312B/C, G7112B, K1312B, G4782A), the test is run for both
pump heads for channels A and B.
Agilent InfinityLab LC Series 1260 Infinity II Isocratic and Quaternary Pumps User Manual
piston 1
at rear position
piston 1
delivers
about 100 bar
below target
pressure
piston 2
at rear position
piston 2
delivers
("System Pressure Test" on page 113).
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