Model 88C Instruction Manual
4
Operation
The Model 88C Resistivity Meter can measure resistivity of fluid samples and
semisolid samples (e.g., filter cakes or mud solids). Procedures for both types of
samples are listed here.
The resistivity chart or nomograph (Figure 4-1) is used to determine the quantity of
sodium chloride (in combination with distilled water or other salt-free aqueous
medium) that is required to produce a solution with the same resistivity as the
sample. The concentration for carbonate salts, calcium salts, and hydroxyl salts can
be found in conductance tables for aqueous solutions.
4.1
Fluid Samples
This procedure explains how to measure resistivity of liquids, filtrates, and drilling
fluids.
1.
Remove the Sample Cell from the Resistivity Meter and fill it with the test
sample. When filling the cell with filtrate, fill and discharge the sample several
times before the final filling.
Make sure there are no bubbles in the sample.
2.
Reattach the sample cell onto the pins on the meter.
3.
Insert the temperature probe in the wall in the sample cell, set the MODE
switch to TEMP and allow the temperature reading to stabilize. This will take
at least three minutes if meter and sample are not at room temperature.
4.
Set the MODE switch to RES, read and record the resistivity in ohmmeters.
5.
Remove the sample cell and clean it with distilled water. If necessary, use a
pipe cleaner and mild soap to clean the cell bore.
207980
Revision F, October 2017
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