VWR PH-130 - Checking Electrode Condition

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11. CHECKING THE ELECTRODE CONDITION
After pH electrode calibration the meter calculates its parameters: offset in
pH units and slope defined as efficiency in percents.
The electrode offset may be defined in pH or mV units.
An ideal electrode immersed in the 7.00 pH buffer before calibration should
indicate 7.00 pH which equals 0.00 mV. If the reading is different, it informs
that the electrode has an offset, which may be reduced by calibration.
The SEM parameter may be also checked by immersing the electrode in 7.00
pH buffer and switching the meter to measurement in mV.
When the electrode is calibrated, its condition may be checked. To check,
enter the calibration points screen according to description in the point 9.1. At
the top of the screen (Pic. 5C) two parameters, determined during the last
calibration are displayed:  (zero offset in pH) and (condition in %).
In case of the electrode condition loss, the zero and condition parameter are
displayed in yellow; in case of calibration validity date expiry if the last
calibration date is also displayed in yellow.
In case of one-point calibration, only the zero offset parameter is displayed.