3B Scientific pH and Temperature Meter (115 V, 50__60 Hz) - Handbuch (Seite 11)

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3B Scientific - www.3bscientific.com
Instructions for use
The instrument is powered by activating the switch marked 'POWER'.
Immediately on power-on the instrument displays the version number (i.e. 'r 1 r 1 r 1 r 1 r 1.00 .00 .00 .00 .00' for approx. 2 secs.).
The pH/Temperature meter is now ready for use.
pH-measurement is selected with the push-button 'pH'. Switching between temperature compensation
with ambient temperature or thermocouple, is selected with a second push on the button. The LED-diode
next to the button is lit constantly when ambient temperature is selected, when flashing the thermocouple is
selected. Fast flashing LED-diode indicates manually selected temperature compensation from the PC.
This mode can not be selected with the push-button.
The temperature reading in
o C/K is selected with the push-button 'TEMP. o C/K'. The push-button tog-
gles between o C (or o F) and Kelvin.
Selection of reading in Celsius or Fahrenheit is done with the PC programme and the instrument con-
nected. The selection is stored in the instruments nonvolatile memory. Default is Celsius.
pH Meter
Use push-button 'pH' to select the 'pH' function, and connect the pH-electrode to the 'pH SENSOR'
input.
Calibration of the pH-electrode:
The following two parameters are used:
• Zero point value: The pH value of the probe giving an output of 0 mV (ideal value pH=7.00).
• Relative sensitivity: The sensitivity of the pH probe relative to the Nernst Equation.
Calibration procedure - not using the PC-programme:
The instrument supports two methods of calibrating the pH probe. The 1-buffer method is the simple and
easiest to do, and sufficient for measurements in solutions in the range pH 6 to pH 8.
1-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 and push the ' TEMPERATURE ' to abort
the sensitivity adjusting (and using the last memorized sensitivity).