Waters Prep Series Installation And Maintenance Manual page 129

Gradient table values (Continued)
Time Flow
45.00 1.00
To perform a solvent proportioning valve pair test:
1. Go to the OPERATE METHODS screen.
2. Press the START RUN screen key.
3. When the detector baseline is stable at 0%, do the following:
a. Change the detector sensitivity to 0.1 AUFS.
b. Set the baseline to 10% full scale by adjusting the recorder's zero
adjustment.
c. A 5% change on the recorder now equals a 1% change in
composition.
Evaluate results
The figure "Test results with all valves working" on page 3-46
results obtained from this test when all valves are working.
Valve failure
A valve failure shows as a difference in height between the sections common
to that valve.
For example, if Valve A is malfunctioning, Peaks 1 and 2 (the only two
containing contributions from Valve A) are irregular when compared to Peaks
3 and 4. Similarly, if Valve D is bad, Peaks 2 and 4 are irregular.
%A %B
0 100
%C %D
0 0
is typical of the
Performance tests
Curve
11
3-45