Thermo Scientific Orion 320, User Manual

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3-3 Thermo Scientific Orion 320, 350 and 370 PerpHecT
®
LogR
®
Meter User Guide
1 . Attach the pH electrode to the meter .
2 . Choose either pH 4 .01 and pH 7 .00 buffers or pH 7 .00 and pH 10 .01
buffers; whichever will bracket your expected sample range .
3 . Press the cal key to initiate calibration sequence . The display will show
CAL for two seconds . Press the yes key to accept the last calibration
buffer range (7-4 or 7-10) or select one of these calibration ranges using
the scroll (
▲ ▼
) keys and then press the yes key to accept the buffer
range .
4 . The 7 buffer icon will be displayed . Place the electrode in the pH 7 .00
buffer . The reading will be displayed and updated as the calibration
continues . When the ready icon is shown, indicating electrode stability,
press the yes key to accept the buffer value .
5 . The pH 4 (or pH 10) icon will be displayed . Remove the electrode
from pH 7 .00 buffer and rinse it with distilled water . Place the
electrode in either pH 4 .01 or 10 .01 buffer, depending on calibration
range that was selected . When the ready icon is shown, press the yes
key to accept the buffer value .
6 . SLP will be displayed while the calculated slope is displayed .
7 . The meter will automatically proceed to the measurement mode . The
ready icon will be shown to indicate electrode stability . The icons
for the type of calibration performed will be shown until another
calibration is performed .
8 . If operating in the LogR mode or using an ATC probe, the
temperature-corrected pH reading will be displayed .
9 . Rinse the electrode with distilled water and place it into the sample .
Record the pH and temperature directly from the meter display when
the ready icon is displayed or when the electrode signal is stable .
Two Point Autocalibration