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17. Troubleshooting
17.1 General Errors
Error Message
Possible Causes
Remedy
Factory Cal. Failure
Need Factory Service
The EEPROM chip which
contains the factory calibration
information has failed.
The unit must be returned to TPS for
service.
EEPROM Write Failure
Need Factory Service
User calibration settings have
been lost or corrupted.
Switch the meter OFF for 5 seconds and
switch back ON. If the problem persists,
return the unit to TPS for service.
Data Pointer Error
Logged Data Lost
Data stored in memory has been
lost or corrupted.
Switch the meter OFF for 5 seconds and
switch back ON. If the problem persists,
return the unit to TPS for service.
17.2 Dissolved Oxygen Troubleshooting
Symptom
Possible Causes
Remedy
Unit fails to calibrate, even
with new sensor.
Calibration settings outside of
allowable limits due to previous
failed calibration.
Initialise the unit. See section 15.
•
Zero calibration fails
(Zero is greater than
7.0%)
•
Air calibration fails (Span
is less than 70% or greater
than 135%).
•
Unstable or inaccurate
readings.
1. Membrane is leaking or
broken.
2. Gap between membrane and
gold cathode is dry.
3. Incorrectly fitted membrane.
4. Electrode is empty.
5. Electrode is faulty.
Replace membrane and refill electrode.
ED1 Undo the barrel 3 turns, then re-
tighten to re-flush the filling solution.
YSI Gently pump the pressure
compensation diaphragm several
times.
Membrane should be smooth and convex
with no wrinkles. Re-fit membrane if
necessary.
Replace membrane and re-fill electrode.
Return electrode to factory for repair or
replacement
Blackened Silver anode.
Electrode has been exposed to
sulphides or other chemical
poisoning.
ED1 Remove barrel and soak in 5%
Ammonia solution for 10 minutes. If
anode is still blackened, sand silver
tube with #800 Wet & Dry sandpaper.
YSI Remove pressure compensation
diaphragm and membrane, then soak
in 5% Ammonia solution for 10
minutes.
If cleaning is unsuccessful, return the
sensor to the TPS factory for cleaning and
service.
Tarnished or scratched Gold
cathode.
Electrode has been chemically
poisoned or physically damaged.
Return to the TPS factory for cleaning and
service.
Meters displays “
Probe
”
instead of Dissolved
Oxygen data.
Meter has been calibrated on
ED1 and then a YSI sensor is
connected, or vice versa.
Re-calibrate the Dissolved Oxygen reading
on the new sensor. Meter only keeps
calibration data for one Dissolved Oxygen
sensor.
Meter displays
OVR ppM
or
OVR%
instead of
Dissolved Oxygen data.
1. Electrode has not yet
polarised.
2. Electrode is faulty
Wait for 2-3 minutes for the electrode to
polarise after the
smart
CHEM
-D
is
switched on.
Return electrode to factory for repair or
replacement.
Reading does not change in
any sample being measured
Auto Stability Function has
frozen display (notice the ).
Turn Auto Stability Function OFF or re-
start sampling (see section 7).
Summary of Contents for smartCHEM-D
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