Measurement—direct method – Hach-Lange ISENa38103 User Manual
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11. Push Store to
accept the
calibration and
return to the
measurement
mode.
Measurement—direct method
Before measurement:
The probe must have the correct service-life time stamp. Set the date and time in the meter before the probe is attached.
If complete traceability is required, enter a sample ID and operator ID before measurement. Refer to the HQd meter manual
for more information.
Regular calibration is required for the best measurement accuracy (refer to
on page 3).
Prepare the probe for use (refer to
Measurement notes:
•
Stir the standards and samples at a slow and steady rate to prevent the formation of
a vortex.
•
Stabilization times with smaller concentration changes generally will be longer and
can be minimized by proper stirring and conditioning. Experiment to determine the
proper stir rate if necessary.
•
Note the temperatures of the samples during measurement. Temperatures of
calibration standards and samples should be kept within ±2 °C of each other for
optimal results.
•
Data is automatically stored in the data log when Press to Read or Interval is
selected in the Measurement Mode. When Continuous is selected, data will only be
stored when Store is selected.
•
Between measurements, rinse the probe with deionized water. Blot dry with a lint-free
cloth. For faster stabilization between measurements, put the probe in 100 mg/L
sodium standard (containing Sodium ISA) that is similar in concentration to the
samples to be analyzed.
•
Air bubbles under the sensor tip when submerged can cause slow response or error
in measurement. If bubbles are present, gently shake the probe until bubbles are
removed.
•
If a measurement error occurs, refer to
on page 12.
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