Dionex ICS-900, Руководство оператора

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3 • Operation and Maintenance
Doc. 065215-02 9/09
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3.7 Equilibrating the System
1. Turn on the pump and run at the flow rate recommended for the column.
2. Allow the system to equilibrate. The ICS-900 Control panel displays the
background conductivity (the conductivity of the eluent without the offset
performed by the autozero command).
3. Offset the background and zero the conductivity reading by clicking the
Autozero button on the ICS-900 Control panel.
4. Monitor the system pressure to make sure it is at the expected pressure for the
installed column (refer to the column manual for details) and is stable.
Column manuals typically provide pressure specifications for systems that do
not include a guard column. Expect the ICS-900 system pressure (with a
guard column) to be 15% to 20% higher than the specification in the column
manual.
•
If the pressure is less than expected, air may be trapped in the system.
Release the air by temporarily removing the pump fitting (
P ) on the
injection valve. Allow the air to escape, and then reconnect the fitting.
•
If the pressure is too high, there may be a restriction in the system
plumbing. Refer to the
Section 4.7 for troubleshooting information.
5. Check for leaks in the regenerant bottle.
6. Check that liquid is flowing out of the suppressor
REGEN OUT
waste line.
7. Monitor the baseline conductivity. In general, it should be <30 μ S for a system
set up for anion analyses, and <2
μ
S for a system set up for cation analyses.
Equilibration time varies and it can take some time to reach these expected
values.
If the conductivity is too high, see Section 4.12 for troubleshooting
information. If the baseline is drifting or has excessive “noise” (large
fluctuations in readings), see
Section 4.13 .
3.8 Verifying Operational Status
After the system has equilibrated, verify the actual pump pressure and stability by
monitoring the pump pressure. Record the short-term pressure fluctuations; they
should be less than 0.13 MPa (20 psi). If the pressure fluctuates by more than this
amount, prime the pump (see
Section 3.6 ).