Two-Point Calibration - Endress+Hauser CPM280 Manual Del Usuario

Commissioning

Two-point calibration

1. Press <CAL> until Ct1 appears with the AutoCal TEC function indicator.
2. Immerse the pH electrode into the first buffer solution.
3. Press <RUN/ENTER>.
The AutoRead measurement begins. The electrode voltage (mV) or the buffer nominal val-
ue appears on the display. If the measured value is stable, Ct2 appears.
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At this point, the calibration can be terminated with <M>. This would correspond to a sin-
gle-point calibration. The instrument then uses the Nernst slope -59.16 mV/pH at 25 °C
(77 °F) and determines the asymmetry of the electrode.
4. Immerse the pH electrode into the second buffer solution.
5. Press <RUN/ENTER>.
The AutoRead measurement begins. The electrode voltage (mV) or the buffer nominal val-
ue appears on the display. If the measured value is stable, the instrument displays the value
of the slope and the evaluation of the calibration in calibration range I.
6. Press <RUN/ENTER> again.
COM280 displays the asymmetry in calibration range I.
The asymmetry and slope are evaluated separately. The worst evaluation is indicated on
the display by the sensor symbol.
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Note!
CPM280
Endress+Hauser