LaMotte CON 6 PLUS, Руководство пользователя

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10. CALIBRATION TIPS
Only one calibration is needed for measurement throughout the
entire range of the meter. If a range was not calibrated, the meter will
automatically detect the closest range calibrated and use that calibration
information. However, only the ranges that were calibrated have
maximum accuracy.
If the samples being measured are near to, or greater than 20 mS/cm (10
ppt), or near to or lower than 100 μ S/cm (50 ppm), it is suggested that
the meter be calibrated at least weekly.
If the samples being measured are in the mid-range and the probe is
rinsed with deionized water and stored dry, the suggested calibration
frequency is at least monthly.
Wet the probe for 10 minutes before calibrating or taking readings to
saturate the probe surface and minimize drift. If measurements are taken
at extreme temperatures, calibrate the meter at least once a week.
Only probes speci
fi ed for the CON 6 PLUS and TDS 6 PLUS meters
should be used. These probes have a built-in temperature sensor. If
a probe without a temperature sensor is used, the temperature of the
solution must be measured separately and entered manually.
11. CALCULATING TDS CONVERSION
FACTOR
The meter can be calibrated with TDS calibration standard solutions. The
calibration standard must be the TDS value at a standard temperature
such as 25 °C. To determine the conductivity-to-TDS conversion factor
use the following formula:
Factor = Actual TDS ÷ Actual Conductivity @ 25 °C
Actual TDS: Value from the solution bottle label or standard prepared
with high purity water and precisely weighed salts.
Tip: ppm = milligrams of salt per liter of water
Actual Conductivity: Value measured using a properly calibrated
Conductivity/Temperature meter.
Both the Actual TDS and the Actual Conductivity values must be in
the same magnitude of units. For example, if the TDS value is in ppm
the conductivity value must be in μ S/cm; if the TDS value is in ppt the
conductivity value must be in mS/cm.