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MW170 Bench Meter
Zero Calibration
For zero calibration, keep the dry probe in the air. This type of calibration can be performed
to correct readings around 0.00 µS/cm. The slope is evaluated when the calibration is
performed in any other point.
One-Point Calibration
1. Place the probe in the calibration solution making sure that the sleeve holes are
completely submersed. Center the probe away from the bottom or beaker walls.
2. Lift and lower the probe to refill the center cavity and tap the probe repeatedly to
remove any air bubbles that may have been trapped inside the sleeve.
3. Press CAL/EDIT to enter calibration. The first LCD line displays the EC reading, the second
LCD line displays the CAL tag and the third LCD line the closest calibration point.
4. To select a different standard value, press the
keys. The hourglass symbol and
“WAIT” message (blinking) are displayed until the reading is stable.
5. When the reading is stable and close to the selected calibration standard, SOL STD
and ACCEPT tags are displayed blinking.
6. Press GLP/ACCEPT key to confirm calibration. The instrument displays “SAVING”, stores
the calibration values and returns to measurement mode.
Note: The TDS reading is automatically derived from the EC reading and no calibration
is needed.
Manual Calibration
This option may be used to perform a manual calibration in a custom standard, i.e. to set
the cell-constant value directly.
To minimize cross-contamination, use two beakers: one (1) for rinsing the probe and the
other (2) for calibration.
1. Rinse the probe in the calibration standard and shake off any excess solution (beaker 1).
2. Place probe in standard making sure sleeve holes are completely submersed (beaker 2).
3. Press SETUP and use the
keys to select C.F. (cm
-1
).
4. Press CAL/EDIT.