Hach-Lange ISEF12103 User Manual - Manual (Page 12)

Message or symptom Possible cause Action
Drifting/inaccurate readings
Dirty sensing element Clean the probe (refer to Clean the probe
on page 10).
Clogged reference Rinse reference junction with deionized water
thoroughly and shake the probe downward to
remove any air bubbles. The air bubbles will not be
visible.
Improper storage conditions Clean or condition the probe and attempt another
calibration. To re-condition the probe and reference
junctions, allow the probe to soak in a conditioning
solution (that contains ISA) for at least 30 minutes
prior to use.
Stabilization criteria not optimized
for the application Adjust the stabilization criteria in the measurement
options menu.
Magnetic stirrers may generate
sufficient heat to change solution
temperature. Put a piece of insulating material between the stirrer
and beaker.
Damaged probe Contact a Technical Support Representative.
Electromagnetic Forces (EMF)
such as voltaic cells, thermoelectric
devices, electrical generators,
resistors and transformers Do not use in areas where EMF is present.
Bubbles trapped under sensor tip Gently shake the probe until bubbles are removed
from under sensor tip.
Out of range Measurement value is outside of
range Make sure that the sample is within the range of the
probe.
Out of limits
Check standard value is outside of
limits set in the current method Make sure that the standard is within the limits of the
current method.
Make another method that expands the acceptable
limits.
Measurement value is outside of
measurement limits set in the
current method. Make sure that the sample is within the limits of the
current method.
Make a new method with an expanded range.
Temperature out of range
Calibration temperature value is
outside of range Make sure that the sample temperature is within the
range of the probe.
Make sure that the temperature sensor is working
correctly.
Measured temperature is outside
the range of the probe. Make sure that the standard temperature is within
the range of the probe.
Make sure that the temperature sensor is working
correctly.
Check standard temperature value
is outside of range Make sure that the check standard temperature is
within the range of the probe.
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