wtw Multi 1970i Bedienungsanleitung Seite 22

pH calibration
pH S
mV
1 C T 1
O % mg/l
S/
m
Sal
1/ cm
Time Baud 8 2 4 8
C
°
Day.Month No.
%
Year Ident
Tref25 Tref20 Auto Store REL1
LoBat nLF Lin Oxi Cal TEC ARng AR
pH
S mV /
1 C T 2
O % mg/l
S/
m
Sal
1/ cm
Time Baud 8 2 4 8
C
°
Day.Month No.
%
Year Ident
Tref25 Tref20 Auto Store REL1
LoBat nLF Lin Oxi Cal TEC ARng AR
pH S mV/
- 5 9 4
% mg/l
O
S/
m
Sal
pH
S mV
1 2
O mg/l
S/
Sal
22
AutoCal TEC procedure (single-point and two-point calibration):
Connect the pH electrode to the measuring instrument.
If necessary, press the <M> key several times shortly until the status
display pH (pH measurement) or U (measurement of the ORP voltage)
appears.
Press the <CAL> key. The Ct1 display and the function display AutoCal
/ pH
TEC appears. The sensor symbol displays the evaluation of the last
cm
calibration (or no sensor symbol in the delivery state or after the
Sal
measurement parameters have been reset).
/
K
TP
REL2
Immerse the pH electrode in the first buffer solution.
RCL
When measuring without a temperature sensor:
Enter the temperature of the first buffer solution with <▲> <▼> while
pressing the <RUN/ENTER> key.
Press <RUN/ENTER>. The AutoRead measurement begins. The
electrode voltage (mV) or the buffer nominal value appears on the
display. When the measured value is stable, Ct2 appears.
Note
pH
At this point, the AutoCal TEC calibration can be terminated
cm
with <M>. This corresponds to a single-point calibration. To
Sal
do this, the instrument uses the Nernst slope
/ K
TP
(-59.2 mV/pH at 25 °C) and determines the asymmetry of the
REL2
RCL
electrode.
To continue the two-point calibration, immerse the pH electrode in the
second buffer solution.
When measuring without a temperature sensor:
Enter the temperature of the second buffer solution with <▲> <▼> while
pressing the <RUN/ENTER> key.
Press <RUN/ENTER>. The AutoRead measurement begins. The
electrode voltage (mV) or the buffer nominal value appears on the
display.
When the measured value is stable, the instrument displays the value of
pH
the slope and the calibration evaluation.
cm
Press <RUN/ENTER>. The instrument displays the value of the
pH
asymmetry.
cm
Switch to the measuring mode with <M>.
Multi 1970i