Xylem inoLab 7110 WASTEWATER pH METER - Manual (Page 20)

pH value pH 7110
20 ba75925e02 12/2011
Calibration determines and stores the current values of the zero point and
slope. Thus, you should calibrate at regular intervals.
5.2.2 When to calibrate?
• When the calibration interval has expired
• Routinely within the framework of the company quality assurance
• After connecting another combination electrode
5.2.3 Automatic calibration (AutoCal)
Use any one to three buffer solutions of a buffer set (technical buffers or DIN
buffers) in ascending or descending order.
Below, calibration with Technical buffers (TEC) is described. When other buffer
sets are used, other nominal buffer values are displayed. Apart from that, the
procedure is identical.
1. Start the calibration with <CAL>.
The calibration display for the first buffer appears.
2. When measuring without temperature sensor: Temper the buffer or
measure the current temperature.
3. If necessary, press <CAL> to select the buffer set used ([AutoCal TEC],
[AutoCal DIN]
).
Ct1
or Cd1 is displayed.
4. Thoroughly rinse the pH electrode with deionized water.
5. Immerse the pH electrode in the first buffer solution.
6. When measuring without temperature sensor: Enter the temperature of
the buffer with <><>.
7. Start the measurement with <ENTER> .
The measured value is checked for stability (stability control).
The [AR] status display flashes.
The electrode voltage (mV) or the nominal value of the buffer is displayed
(setting: see section 7.1.1 C
HANGING THE SETTINGS FOR P H MEASURE -
MENTS , page 29).
8 4 2
1 T C
°C
pH
AutoCal TEC
TP