13. LIST OF POSSIBLE ANOMALIES AND RELATIVE SOLUTIONS
The instrument
always indicates pH
7.00
Problem with the cable and/or
connector.
1) Check for possible short circuits on the
electrode instrument connection cable
(between the cable’s core and the external
shielding).
2) Make sure that there are no traces of
humidity and/or condensation on the
connector of the probe or the device.
3) Make sure that 100 resistance is
present between terminals 11 and 12.
The instrument
always indicates a
high or continuously
unstable value
The electrode’s connection
cable is damaged.
There is an air bubble in the
electrode’s membrane.
Place the electrode vertically and shake it
slightly until the air bubble rises.
N.B.: The electrode must be vertical or
tilted by a maximum of 45°.
Connection cable too long or
too close to an electrical wire:
Disturbance.
Reduce the distance between the device
and the probe.
Impossible to
calibrate the pH 7
value
Error shown on the
display
Calibration quality of
pH probe < 20%
Unsuitable buffer solution.
Make sure that the solution used is pH 7.
Check the buffer solution pH using an
electronic pH-meter.
Use a new pH 7 buffer solution and restart
calibration.
Problem on probe’s porous
material, dirt deposits.
Make sure that the probe’s porous material
is in good condition; wash the electrode
using a diluted acid-based solution and dry
with a soft cloth.
Impossible to
calibrate the pH 4
value
Error shown on the
display
Calibration quality of
pH probe < 20%
Unsuitable buffer solution.
Make sure that the solution used is pH 4.
Check the buffer solution pH using an
electronic pH-meter.
Use a new pH 4 buffer solution and restart
calibration.
Problem with the electrode
bulb.
Make sure that the electrode bulb is not
damaged. Make sure that it did not become
dry outside of the water. As a last resort,
clean the electrode and leave it immersed
in the water for a few hours.
Electrode electrostatically
charged.
During the calibration phase, the electrode
MUST NOT be dried with a cloth or paper;
let it drip.