Thermo Fisher Scientific pH/ORP/Conductivity Field Monitors - Manual (Page 7)

4
Immerse pH electrode into
buffer solution,
for example, pH 7
Press
Press
4.2 pH Calibration
1. Plug in the pH monitor to turn on. The monitor will
be in pH measurement mode.
2. Rinse the probe thoroughly with de-ionized water or
a rinse solution. Do not wipe the probe; this causes
a build-up of electro-static charge on the glass
surface.
3. Dip the probe into the calibration buffer pH 7. The
end of the probe must be completely immersed into
the sample. Stir the probe gently to create a
homogeneous sample.
4. Press the CAL key to enter the calibration mode.
"CA" will flash on the display for a second and then
a value close to pH 7.0 will flash.
5. Let the electrode soak in the buffer until reading is
stable, stirring occasionally (time will vary
depending on temperature and electrode
condition). When the display has flashed the same
pH value for 15 seconds or more, press the ENTER
key. "CO" will flash on the display. The reading
should now display pH 7.0. See Figure 2.
If necessary, repeat steps 2 through 5 for the
remainder of the buffer values (pH 4.0 and 10.0).
Figure 3 - pH
Calibration