Thermo Scientific Dionex ICS-5000, Operator'S Manual

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2 • DC Description
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•
In the Inject position, carrier liquid flows through the sample loop and on
to the concentrator column, carrying the contents of the sample loop with
it. Excess flows out to waste. Eluent flows from the pump, through the
valve, and to the separator column, bypassing the concentrator column.
2.14 CD Conductivity Detector
Each Dionex ICS-5000 Conductivity Detector (CD) consists of a heated
conductivity cell and the electronics required for collecting the conductivity
data and sending it to the computer and the analog output (if installed). The
CD is installed in the upper compartment of the DC (see
Figure 2-21 ).
Two versions of CD are available:
•
A capillary CD (P/N 072041), for use in systems running capillary flow
rates
•
An analytical CD (P/N 061716), for use in systems running analytical
(standard bore or microbore) flow rates
The features and functions of the two CD versions are the same. However,
because the cell volumes of the two are different, the versions are not
interchangeable. The CD version must match the system type (capillary IC or
analytical IC). If the CD version and system type are mismatched,
chromatograms will be affected (for example, broad peaks or lowered
sensitivity).
2.14.1 Heated Conductivity Cell
The flow-through conductivity cell measures the electrical conductance of
analyte ions as they pass through the cell. Two passivated 316 stainless steel
electrodes are permanently sealed into the PEEK cell body. The cell design
provides efficient sweep-out, low volume (<1

L), and low dispersion.
Temperature control and compensation help ensure good peak reproducibility
and baseline stability.
Temperature Control
Temperature directly affects the conductivity of a solution. For example,
laboratory heating and air conditioning systems can cause a regular slow