3B Scientific pH and Temperature Meter (115 V, 50__60 Hz) - Handbuch (Seite 12)

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3B Scientific - www.3bscientific.com
The 2-buffer method is for accurate measurements in the full pH measurement range.
2-buffer adjusting:
• Push and hold the 'TEMPERATURE'-button when turning on the instrument with ON/OFF-
switch, until 'Ad Ad Ad Ad Adj jj jj' is shown in the display. The instrument is now ready for the calibration steps,
and 'BUF7' is displayed. The pH probe is placed in a pH 7.00 buffer solution.
• When the reading on the display has settled, adjust with the knob 'BUFFER adj.' to the
display reading 7.00.
• Push the 'TEMPERATURE' to save the adjustment in the instrument, and the 'SLOP SLOP SLOP SLOP SLOP' is dis-
played for a few seconds. Now rinse the pH probe.
• The pH probe is placed in a pH 4.00 buffer solution.
• When the reading on the display has settled, adjust with the knob 'BUFFER adj.' to the
display reading 4.00.
• Again push the 'TEMPERATURE'-button to store the calculated sensitivity in memory. Rinse
the pH probe thoroughly.
Please observe that each time the pH meter is turned on, at least a 1-buffer adjusting must be performed. The ‘Rela-
tive sensitivity’ of the electrode is memorized, but the ‘Zero point value’ is not.
Tip: The ‘Zero point value’ is displayed if you short-circuit the BNC-input, after a calibration has been performed.
pH measurement
The instrument is now ready for measuring, with one of the three temperature compensation methods
available (the two first can be selected with the 'pH '- button, the third only by the PC-program):
• Ambient temperature: 'pH ' LED has constant light.
The internal temperature sensor of the instrument is used for compensation.
• NiCr.-Ni thermocouple: 'pH ' LED is flashing.
Use the connected thermocouple to measure the temperature of the pH solution.
• Manual temperature: 'pH
' LED is flashing fast.
This is only available through the PC-programme.
Calibration of the pH probe and temperature measuring - only through PC-programme:
Using the delivered PC-Software (on CDROM) the instrument can be calibrated.
• Relative sensitivity: The sensitivity of the pH probe relative to the Nernst Equation.
• Zero point value of the temperature meter: Can be adjusted.