Thermo Scientific Star A326, Instruction Sheet

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Orion Star A326 Portable pH/RDO/DO Meters
4
pH Calibration
One to five pH buffers can be used for calibration. Always use fresh pH buffers and select buffers that bracket
the sample pH and are one to four pH units apart. Prepare the pH electrode according to the instructions in
the electrode use guide. Connect the pH electrode and any other electrodes to be used (ATC probe, reference
electrode) to the meter. Power on the meter and set the measurement mode to pH.
1. In the measurement mode, press f1 (cal) . Press or to highlight pH-Channel and press f2 (select) .
2. Rinse the pH electrode and any other electrodes in use with distilled water, blot dry with a lint-free tissue
and place into the pH buffer.
3. When the electrode and buffer are ready, press f3 (start) .
4. Wait for the pH value on the meter to stabilize and stop flashing and perform one of the following actions:
a. Press f2 (accept) to accept the displayed value.
b. Press f3 (edit) to access the numeric entry screen and edit the value.
i. Press , , or to highlight a number, decimal point or negative sign; press
f3 (enter) to select the highlighted item and repeat until the value at the measured temperature
is shown above the numeric entry screen.
ii. Press f2 (done) to exit the numeric entry screen.
iii. Press f2 (accept) to accept the entered value.
5. Press f2 (next) to proceed to the next buffer and repeat steps 2 through 4 or press f3 (cal done) to save and
end the calibration. If five buffers are used, the calibration will save and end once the fifth value is accepted.
a. If a one point calibration is performed, press f2 (accept) to accept the displayed slope value or press
f3 (edit) to access the numeric entry screen, enter the slope value and press f2 (accept) .
6. The meter will display the calibration summary including the average slope. Press f1 (meas) to export
the data to the calibration log or press f2 (print) to export the data to the calibration log and a printer or
computer. The meter will automatically proceed to the measurement mode.
pH Buffer Group Selection
The selected buffer group allows for the automatic recognition of certain pH buffers during a pH calibration.
The USA buffer group includes pH 1.68, 4.01, 7.00, 10.01 and 12.46 buffers and the DIN buffer group includes
pH 1.68, 4.01, 6.86, and 9.18 buffers.
1. In the measurement mode, press .
2. Press , , or to highlight pH Channel and press f3 (select) .
3. Press or to highlight Mode and Settings and press f3 (select) .
4. Press or to highlight Buffer Group and press f3 (select) .
5. Press or keys to highlight USA or DIN and press f3 (select) .
6. Press to return to the measurement mode.