24
CALIBRA
TION
8.3. EC PROBE CALIBRATION (HI763093)
It is recommended to calibrate the instrument frequently, especially if high accuracy is required.
More frequent calibrations may be required depending on the type of sample being tested, i.e. turbid
biologically active water samples will require more frequent cleanings and calibrations than cleaner
waters.
The probe should be recalibrated:
• Whenever the probe is replaced.
• At least once a week.
• After testing aggressive samples.
• After cleaning the sensor.
• If “Outside Cal Range” message blinks during measurement (the measurement is outside the
current calibration range).
• If enabled, when the “CAL DUE” calibration time out message is displayed.
Before performing a conductivity calibration inspect the EC sensor for debris or blockages. The EC
electrodes are situated inside the two small channels found in the bottom of the conductivity sensor.
Clean using the small brush from the probe maintenance kit. Flush with water before calibration.
CONDUCTIVITY
From the
Calibration
menu, use the
/
keys to highlight
Conductivity
and then press
Select
.
• Pour small quantities of the calibration solution into clean beakers. To minimize cross-contamination,
use two beakers: the first one for rinsing the sensor and the second one for calibration.
• To change the calibration solution, press the
Cal. point
, use the
/
keys to select the new
buffer, press
Select
to use the highlighted value.
• Submerse the EC electrode into the calibration rinse solution and move it up and down gently to
fill the EC sensor channels with solution.
• Submerse the EC electrode into calibration solution, tap the electrode gently to remove any trapped
air bubbles. The “Not Ready” message is displayed.
• Once the reading has stabilized, the countdown timer will count down until the display shows the
“Ready” message.
• Press
Confirm
to accept the calibration point.
• Press
OK
to return to the
Calibration
menu.
• Press
Measure
to return to the measurement screen.
