Thermo Scientific Orion Star LogR Meter, Руководство пользователя

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26 Thermo Scientific Orion Star LogR™ Meter User Guide
Chapter VIl
LogR and Automatic
Temperature Compensation (ATC)
Calibration
LogR Temperature Calibration Information
This procedure should be performed at least once per week to ensure accurate
temperature compensation when operating in the LogR mode. If the meter is
powered down or the electrode is disconnected, the LogR temperature should be
recalibrated. When using the meter for the first time or restarting the meter in the
LogR mode, a LogR temperature calibration must be performed. It is recommended
that at least a two-point temperature calibration be performed to meet optimum
system accuracy. Up to three points can be calibrated. Refer to the
Appendix B
for
additional information.
Choose a temperature calibration range that is at least 5 °C apart, depending on your
expected operating range. Evenly bracket your expected sample temperature range.
A maximum 20 °C range is recommended for maximum accuracy. For example, for
measurements around 20 °C, calibrate at 10 °C and 30 °C. For a temperature span
greater than 20 °C, a three-point temperature calibration is recommended. For many
samples, a single-point calibration near the expected sample temperature will yield
adequate results. A constant temperature bath or a hot plate is recommended to
hold the temperature of calibrating solution.
For best results during temperature calibration, it is recommended that a pH buffer
or tap water be used as the temperature calibrating solution. Do not use distilled
water because the conductivity is too low to obtain a good calibration.