NAVI D-25 Instruction Manual page 172

● ERR No.05 Electrode sensitivity error (DO)
D-52/53/54/55
Explanation
If there was something wrong with the DO calibration,
re-calibrate after taking the appropriate measures listed
below.
Cause
The settings
(temperature,
correction of
salinity
concentration,
or air-pressure
correction) are
wrong.
There is liquid
on the DO tip
membrane.
(when
conducting air
calibration)
There is
something
wrong with the
standard
solution.
(when
conducting
standard
solution
calibration)
The stirring is
inappropriate.
The electrode is
defective.
6 Maintenance and Troubleshooting
How to solve problem
Reconfirm each setting
(temperature, correction of salinity
concentration, and air-pressure
correction).
Let the electrode sit until the liquid
evaporates or remove the liquid
using soft tissue paper, making sure
not to scratch the membrane.
Prepare new zero and span
standard solutions.
Stir the solution appropriately (at a
constant speed, between 1000 and
1500 rpm). (Make sure the stirrer
does not emit heat.)
If the DO tip is dirty, clean it.
If the DO tip membrane is damaged
or the DO tip is worn out, replace it.
6.5 Troubleshooting
161