Thermo Scientific Orion 320, User Manual

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3-6 Thermo Scientific Orion 320, 350 and 370 PerpHecT
®
LogR
®
Meter User Guide
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 . Refer to the Appendix for accuracy
specifications and recommended calibration techniques .
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 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 .
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 . Refer to the Appendix for
additional information .
LogR Temperature
Calibration