YSI 3100 - Manual (Page 13)

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3.5 Making Measurements
After setting up the 3100 instrument and cell as described earlier, the following basic steps
should be used to make measurements.
1. Verify that the 3100 is properly set up to use the current cell by measuring, or calibrating
with, a standard conductivity solution. See section 4.1 Cell Calibration.
2. Immerse the cell in the solution to be measured.
3. Gently tap the cell to remove any air bubbles and dip the cell in the solution 2 or 3 times
to ensure proper wetting. The cell electrodes must be submerged and the electrode
chamber must not contain any trapped air. If using a flow through or fill cell, be certain it
is completely full.
4. Allow time for the temperature to stabilize.
5. Press the [MODE] key to select the units required, then read the display.
6. Rinse the cell with distilled or deionized water.
3.6 Autoranging & Range Searching
The YSI Model 3100 is an autoranging instrument. This means that, regardless of the
conductivity or salinity of the solution (within the specifications of the instrument), all you need
to do to get the most accurate reading is to put the cell in the sample. This feature makes the
Model 3100 as simple as possible to operate.
When you first place the cell into a sample or calibration solution, and again when you first
remove the cell, the instrument will go into a range search mode that may take as long as 5
seconds. During some range searches, the instrument display will flash rANG to indicate its
movement from one range to another.
rANG
The length of the range search depends on the number of ranges which must be searched in order
to find the correct range for the sample. During the range search, the instrument will appear to
freeze on a given reading for a few seconds then, once the range is located, will pinpoint the
exact reading on the display. The display may also switch to 00.0 for a second or two during a
range search before it selects the proper range.
During normal operation, the [ENTER] key enables and disables the autoranging feature of the
instrument. See 4.4 Manual Ranging if you need to switch to manual ranging.
3.7 Platinization
The 3100 can be used to replatinize the electrodes of the cell. See section 5.2 Platinization for
details.