DDPHCL2_man_r1.0 – 03/2021
Page 15
Electrochemical Calibration
pH Calibration
1) Rinse the pH electrode with distilled water, then immerse it in the pH 7.01 pH buffer solution
2) Press the CAL key to enter the menu mode and
use the
keys to select the option “IN1
CALIBRATION”
3) Press CAL again to confirm
4) Press
to select the OFFSET calibration and
confirm by pressing CAL
5) The system automatically recognizes and displays the buffer value (7.01 pH)
6) If necessary, use the
keys to adjust the calibration value
7) Press CAL to confirm the calibration, or ESC to quit the procedure and keep the previous calibration
8) Rinse the pH electrode with distilled water, then immerse it in the pH 4.01 (or 9.01) buffer solution
9) Press the CAL key to enter the menu mode and use the
keys to select the option “IN1
CALIBRATION”
10) Press CAL again to confirm
11) Press
to select the GAIN calibration and
confirm by pressing CAL
12) The system automatically recognizes and
displays the buffer value (4.01 or 9.01 pH)
13) If necessary, use the
keys to adjust the
calibration value
14) Press CAL to confirm the calibration, or ESC to quit the procedure and keep the previous calibration
Notes
If the system does not automatically recognize the buffers or the “Calibration Impossible” error occurs, it can
be due to: a) buffer solution contaminated or expired
b) electrode faulty or dead
c) connection cable or connector damaged
If you try to calibrate the offset at a pH value too different from 7.00, the calibration is automatically ignored.
Similarly if you try to calibrate the gain with a buffer solution at a pH too close to neutrality, the procedure will
fail.
During normal operation, it is possible to view the offset (pressing
) and gain (pressing
) values, to check
the electrode status. The ideal values are an offset close to zero and a gain close to 1.000. When these values
are close to the max / min limits (offset: -1.00pH ... +1.00pH; gain: 0.750 ... 1.500), the electrode is
contaminated or dead.
Redox Calibration
1) Rinse the electrode with distilled water, then immerse it in the calibration solution (e.g. 220 mV)
2) Press the CAL key to enter the menu mode
and use the
keys to select the option “IN2
CALIBRATION”
3) Press CAL again to confirm
4) Press
to select the OFFSET calibration and
confirm by pressing CAL
5) The system automatically recognizes and displays the solution value (220 mV)
6) If necessary, use the
keys to adjust the calibration value
7) Press CAL to confirm the calibration, or ESC to quit the procedure and keep the previous calibration
I N 1
C A L I B R A T .
P H
C A L > Y E S
E S C > N O
I N 1
C A L I B R A T .
P H
O F F S E T
G A I N
I N 1
C A L I B R A T .
P H
C A L > Y E S
E S C > N O
I N 1
C A L I B R A T .
P H
O F F S E T
G A I N
I N 2
C A L I B R A T .
R X
C A L > Y E S
E S C > N O
I N 2
C A L I B R A T .
R X
O F F S E T
