Agilent Technologies 1200 series - How to Optimize the Compressibility Compensation Setting

Agilent 1200 Preparative Pump User Manual 67
Optimizing Performance
5
How to Optimize the Compressibility Compensation Setting
How to Optimize the Compressibility Compensation Setting
The compressibility compensation default settings are 75 × 10
-6
/bar (best for
most aqueous solutions). Under normal conditions the default settings reduce
the pressure pulsation to values (below 2 % of system pressure for a complete
system with a preparative scale sized column installed) that will be sufficient
for most applications. If the compressibility values for the solvents used differ
from the default settings, it is recommended to change the compressibility
values accordingly. Compressibility settings can be optimized by using the
values for various solvents described in Table 11 on page 68. If the solvent in
use is not listed in the compressibility table, when using premixed solvents
and if the default settings are not sufficient for your application the following
procedure can be used to optimize the compressibility settings:
1 Start the preparative pump with the adequate flow rate. The system
pressure should be between 50 and 150 bar
2 Before starting the optimization procedure, the flow must be stable. Before
starting the procedure, check the tightness of the system with the help of
the built in pressure test (see “Prep Pump Pressure Test Description” on
page 94).
3 Verify the tightness of the pump itself (piston/seal combinations, valves,
filters fittings, etc.) with the help of the built in Leak Test (see “Prep Pump
Leak Test Description” on page 98).
4 Your pump must be connected to a Agilent ChemStation or handheld
controller, the pressure and %-ripple can be monitored with one of these
instruments.
5 Starting with a compressibility setting of 50 × 10
-6
/bar increase the value
in steps of 10. The compressibility compensation setting that generates the
smallest pressure ripple is the optimum value for your solvent composition.
6 Repeat step 1 on page 67 through step 5 on page 67 for each preparative
pump in a system with a multiple pump setup.
NOTE
Use the preparative pump with a flow rate of at least 20 ml/min.