Calibration procedure (ph and conductivity) – Hach-Lange SENSION+ 50 49 User Manual User Manual
Page 8
• The calibration and sample measurement conditions must be as similar as possible (e.g., the
temperature of the solution, stir procedure, stir rate and position of the probe).
• The temperature sensor is within the conductivity probe. Calibration standards must be at same
temperature (ambient temperature is recommended).
• For pH calibration, at least 2 calibration points are necessary.
• For conductivity calibration, use 1-point calibration and select the standard nearest to the expected
measurement range. Refer to the meter manual for other conductivity calibration options.
• Calibration of conductivity cells is important as the conductivity cell constant can change with time.
The calibration identifies the actual cell constant versus the nominal value.
• Do not dilute conductivity standards or samples.
• For dissolved oxygen calibration, a water-saturated air calibration is recommended. Refer to
Calibration procedure — DO probe, water-saturated (100%) air
on page 7.
• When the probe is submerged, make sure that there are no air bubbles under the probe sensor
tip(s). Gently shake the probe from side to side to remove any air bubbles.
• Make sure that the reference junction of the pH probe is fully immersed in the solution.
• If the stabilization is slow, shake the multisensor from side to side to stir the solution.
• Always hold the multisensor by the handle. Do not hold by the probe tubes to avoid the heating of
the solutions.
• If a calibration error occurs, refer to
Calibration procedure (pH and conductivity)
1. Connect the
multisensor to the
meter. Set the meter to
on.
Note: For dissolved
oxygen calibration, refer
to
— DO probe, water-
saturated (100%) air
on page 7.
2. Push Calibrate. The
parameter flashes on
the meter display. Use
the arrow keys to
change the parameter,
if applicable.
3. Push Calibrate to
select the parameter.
The standard flashes
on the meter display.
Use the arrow keys to
select the applicable
standard solution.
Note: pH buffers are
automatically
recognized.
4. Prepare the
standard solutions in
the probe storage
tubes. Add
approximately 6.4 mm
(¼ inch) of standard.
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