31
2.
Check electrode leakage - The electrode is designed to leak a small
amount of filling solution through the gap between the sensing pellet
and the epoxy body. If the leak rate is too slow or too fast the
performance of the electrode may be adversely affected. The electrode
leak rate should be between 0.2 cm and 3 cm in 24 hours (as measured
from the filling hole to the top of the fill solution).
3.
Check for sample contamination. Some samples contain high levels of
sulfur, heavy metals, waste oil, or other organics that may carry over to
the final extract. If these compounds come into contact with the
electrode, they can poison the sensing element. The output from the
electrode will deteriorate with repeated exposure to these contaminants.
If repeated samples cause a drift error, but the electrode checks out with
the standard solutions, check for sample contamination.
CHECK
ELECTRODE
:
This message indicates that the electrode output has exceeded 180 mV. If
this message appears, the electrode has been damaged or the wrong
electrode has been attached to the
L2000
DXT
analyzer. Check for the
correct electrode then follow steps for restoring an electrode.
Measured Result
9999
:
This result for an unknown measurement indicates that the calculated
reading is above 5000 ppm in analyte concentration. This message only
appears during an unknown measurement. If this occurs, re-analyze the
sample using a smaller sample size. The result 9999 will be stored in the
data file as a result and must be accounted for when interpreting the data
as this is not an actual result.
Measured Result
-9999
:
This result indicates that an unknown reading has resulted in a negative
analyte concentration. This can be caused by either an electrode
malfunction or an improper blank value used, i.e., a large blank value not
representative of the true blank. If this occurs, check the blank value
used or check the electrode function as described above. If the electrode
checks out, investigate possible co-contaminants in the sample that may
have adversely affected the electrode. A value of -9999 will be stored in
the data file and must be accounted for when interpreting the data as this
is not an actual result.
LOW BATTERY
: If the battery voltage drops below the operational level of the instrument,
the display will read
“LOW BATTERY”
followed by the message
“Power Off”
at which time the instrument will turn off automatically.
TEMPERATURE
OUT OF RANGE:
A temperature error can be caused by either: