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Instruction Manual
CON 11/110
18
4.7 TDS
Calibration
4.7.1 Calibrating for TDS Using Conductivity Standards & adjusting TDS factor
It is important to note that the increase in concentration of salts dissolved in solution
increases the conductivity of that solution. This relationship varies from salt to salt
and is roughly linear over a given range for a given salt. The TDS conversion factor is
the number used by the meter to convert from conductivity to TDS.
Instead of calibrating for TDS directly using TDS calibration standard solutions, you
can have TDS calibration by using the conductivity calibration method and enter the
appropriate TDS conversion factor into the meter.
For more information regarding TDS Conversion Factor determination, please refer to
page 73.
4.7.2 Setting the TDS Conversion Factor
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.
1. Press MODE key to select TDS mode.
2. Press Setup key to enter SETUP Menu.
3. Press
the
HOLD/ENTER
key a few times to scroll
through the sub programs until you view Program
P1.4
4. Press the HOLD/ENTER key again. The upper
display shows a value and the lower display shows
“tdS”.
5. Press the MI/
▲
or MR/
▼
keys to select your
calculated TDS conversion factor.
6. Press the HOLD/ENTER key to confirm selection
and to return to the subgroup menu.
7. Press the CAL/MEAS key to return to
measurement mode.
NOTE: The set up program P1.4 for setting the TDS
conversion factor is only activated when set up menu is
entered while the meter is in the TDS measurement mode.
ppt
ppm
SETUP
p 1.4
ppt
ppm
SETUP
0.50
ppt
ppm
SETUP
0.75
SETUP
cof
p 1.0
SETUP
MI
MR
HOLD
ENTER
HOLD
ENTER
Only from TDS Measurement Mode
Figure 14: Setting the TDS
Conversion Factor