Thermo Scientific Dionex UltiMate 3000 Series Operating Instructions Manual page 119

ProFlow flow meter: Interdependency of column pressure and the maximum flow rate
The maximum column pressure depends on the solvent that is used in solvent channel B and
the flow rate. The table below shows which column pressures can be delivered at the given
flow rates for a number of solvents:
Solvent (%B) 1500 nL/min
100 % 900 bar
acetonitrile
80:20 890 bar
acetonitrile/
water
100 % 890 bar
methanol
100 % water 830 bar
100 % 610 bar
isopropanol
Tip: Pressures above 860 bar delivered by the pump may cause problems with the
column switching-valves. Make sure that you observe the maximum pressure
limit for the column switching valves.
Example:
If you use 100 % water in solvent channel A and acetonitrile/water (80:20) in solvent
channel B at a flow rate of 1500 nL/min, check the table entry for acetonitrile/water (80:20)
above; a maximum column pressure of 890 bar is possible with the pump.
The Ready Check checks if the selected flow rate can be delivered reliably at the selected
maximum column pressure. If this is not possible, a message appears. If the upper limit for
the column pressure is set to a value that is considerably higher than the actually expected
column pressure, a message may appear too although no problem has occurred. In this
case, reduce the upper limit as required.
If it is required to work at very high column pressures and the selected flow rate cannot be
delivered, reducing the flow rate and pressure limit slightly will usually be sufficient to
remedy the situation. The maximum expected column pressure decreases with the flow rate.
During operation, the pump continuously monitors whether the selected flow rate is delivered.
If it is not, a message appears and the batch or sequence will be aborted. A number of factors
determine whether this situation will actually occur, such as the selected gradient.
Operating Instructions
Maximum possible column pressure at flow rate
1250 nL/min 1000 nL/min
900 bar 900 bar
900 bar 900 bar
900 bar 900 bar
850 bar 880 bar
680 bar 740 bar
UltiMate 3000 Series:
NCS-3500RS and NCP-3200RS
750 nL/min 500 nL/min
900 bar 900 bar
900 bar 900 bar
900 bar 900 bar
900 bar 900 bar
800 bar 870 bar
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