In the MPVS Ultra Control User's Manual the setup of a new Rho calibration cuvette is described in detail, however, the statement "... be sure that the gain in the Gain-Conductance Range field is correct. (Unless a need arises to do otherwise, use a gain of x1.)" and the option to select from gains between x1 and x100 in the Rho cuvette tab might be confusing.
The gain-conductance range is intended for optimization of the Rho cuvette volume signal only. It does not have an effect on the conductance volume range measured. Usually the x1 or x2 gain setting is appropriate to capture the signal accurately.
Make sure you are using the K factor assigned to that cuvette. The K factor can be found on the document shipped with the Rho cuvette and on the label attached to the cable.
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