Hanna Instruments HI 95706 - Manual (Page 10)

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The flashing digits indicate that:
1) the month can be set
2) the day can be set
“Storage”: this prompt appears for 1 second at the end of the
calibration procedure, to indicate that the calibration data has
been stored.
“Error”: the concentration of the calibration solution used is not
correct. Repeat the calibration procedure with the right standard
solution, and verify it is not expired. If the calibration procedure fails
again, contact your dealer or the nearest Hanna Customer Service
Center.
ERROR MESSAGES
a) on zero reading
This indicates that the zeroing procedure failed due to a low signal-
to-noise ratio. In this case press ZERO again.
“No Light”: the instrument cannot adjust the light level. Please check
that the sample does not contain any debris.
“Light Low”: there is not enough light to perform a measurement.
Please check the preparation of the zero cuvet.
“Light High”: there is too much light to perform a measurement.
Please check the preparation of the zero cuvet.
b) on sample reading
There is too much light for the sample measurement. Please check
if the right sample cuvet is inserted.
“Inverted”: the sample and the zero cuvet are inverted.
“Zero”: a zero reading was not taken. Follow the instruction in
the measurement procedure for zeroing the meter.
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Under range. A blinking "0.00" indicates that the sample absorbs
less light than the zero reference. Check the procedure and make
sure you use the same cuvet for reference (zero) and measurement.
A flashing value of the maximum concentration indicates an
over range condition. The concentration of the sample is beyond
the programmed range: dilute the sample and re-run the test.
A flashing value lower than the maximum concentration indicates
a low signal-to-noise ratio condition. In this case accuracy of the
result is not guaranteed. Repeat the measurement procedure.
The instructions listed below should be carefully followed during testing to ensure best accuracy.
GENERAL TIPS FOR AN ACCURATE MEASUREMENT
• Suspended matter in large amounts may cause
interference, therefore this should be removed by
prior filtration.
• For a correct filling of the cuvet: the liquid in the
cuvet forms a convexity on the top; the bottom of
this convexity must be at the same level of the 10
mL mark.
• It is important that the sample does not contain any
debris. This would corrupt the reading.
• Each time the cuvet is used, the cap must be
tightened to the same degree.
• Whenever the cuvet is placed into the measurement
cell, it must be dry outside, and completely free of
fingerprints, oil or dirt. Wipe it thoroughly with
HI 731318 (tissue for wiping cuvets, see chapter
ACCESSORIES) or a lint-free cloth prior to insertion.