Thermo Fisher Scientific CyberScan PC 300 - Manual (Page 18)

Instruction Manual PC 300
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4.5 TDS Calibration
4.5.1 Calibrating for TDS directly
The factory default setting for TDS conversion factor is
0.5. If your solution has a different TDS factor, you can
improve calibration accuracy by setting the TDS factor
prior to calibration. See P7.4 for directions.
1. If necessary, press the MODE key to select TDS
mode.
2. Rinse the probe thoroughly with de-ionized water or
a rinse solution, then rinse with a small amount of
calibration standard.
3. Dip the probe into the calibration standard. Immerse
the probe tip beyond the upper steel band. Stir the
probe gently to create a homogeneous sample.
Allow time for the reading to stabilize.
4. Press CAL/MEAS to enter TDS calibration mode.
The CAL indicator will appear in the upper right
corner of the display.
5. Press the or keys to change the value on the
primary display to match the value of the calibration
standard.
6. Press ENTER to confirm the calibration value. The
meter returns to the MEAS (measurement) mode.
See Figure 10.
7. Repeat steps 1 to 6 for other measuring ranges.
NOTES
To exit from TDS Calibration mode without confirming
calibration, DO NOT press the ENTER key in step 6.
Press CAL/MEAS instead. This will retain the meter’s old
calibration data in the measuring range of the calibration.
You can offset the TDS reading up to ± 20% from the
default setting. If your measured value differs by more
than ± 40%, clean or replace probe as needed.
Figure 10 - TDS Calibration