Carl Roth COND 50 VioLab, Instruction Manual

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17
UM Serie 50VioLab EN rev.1 19.05.2020
EN

Automatic pH calibration
Example: three-point calibration with USA type buffers (7.00 / 4.01 / 10.01).

In pH measure mode press the key to enter calibration mode.
The string “1ST POINT PH 7.00” appears on the display; the device requires the neutral value as the
first calibration point.

Rinse the electrode with distilled water and gently dab with paper towel. Dip the electrode in the pH
7.00 buffer solution.

When the signal is stable, the red bands are replaced by the stability icon
.

Press the key as indicated by the string “PRESS OK”.
The measured value flashes on the display and then the icon of the pH
7.00 beaker appears at the bottom left indicating that the instrument is calibrated on the neutral
point.

Remove the electrode, rinse with distilled water and dab gently with paper towel. Dip the sensor in the
pH 4.01 buffer solution (“CHANGE BUFFER”).

The instrument is now ready to recognize the second calibration point.
Next to the string “2ND POINT PH”, the different buffers, that the device can recognize automatically,
scroll.

When the 4.01 value is recognized and the icon appears, press the key as indicated by the
string “PRESS OK”.
The actual measured value and the Slope% flash on the display; subsequently, the icon of the beaker
pH 4.01 appears next to the green beaker, indicating that the instrument is calibrated in the acid
field.

Remove the electrode, rinse with distilled water and dab gently with paper towel. Dip the sensor in the
pH 10.01 buffer solution (“CHANGE BUFFER”).

The instrument is now ready to recognize the third calibration point.
Next to the string “3RD POINT PH”, the different buffers, that the device can recognize automatically,
scroll.

When the value 10.01 is recognized and the icon appears, press the key , as indicated by
the string “PRESS OK”.
Switching from an acidic to a basic pH may take a few more seconds to achieve stability.
The actual measured value and the second Slope% flash on the display; subsequently, the icon of the
beaker pH 10.01 appears next to the green and red beakers, indicating that the instrument is
calibrated in the alkaline field.

At the end of the third calibration point, the instrument returns automatically to measure mode.

To perform a one- or two-point calibration, press the key once finished the first or second point.
Note: electrode calibration is an essential operation for the quality and truthfulness of a
measurement. Therefore, make sure that the buffers used are new, unpolluted and at the same
temperature.
ATTENTION: Before proceeding with the calibration operations, carefully consult the safety data sheets
of the substances involved:

Calibration buffer solutions.

STORAGE solution for pH electrodes.

Filling solution for pH electrodes.