User's Manual

11
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.
Under range. A blinking "0" for 771 or “0.00” for 701 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 (i.e. “500” for
chlorine Ultra High Range 771 or “5.00” for chlorine Low Range
701) 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 (i.e.
“200” for chlorine Ultra High Range 771 or “2.00” for chlorine
Low Range 701) indicates a low signal-to-noise ratio condition.
In this case accuracy of the result is not guaranteed. Repeat the
measurement procedure.
14
MEASUREMENT PROCEDURE
MEASUREMENT PROCEDURE FOR 771
• Select the parameter code “771” for Chlorine
ULTRA HIGH RANGE by holding ZERO/SET
(see page 13).
• When the LCD displays “771”, it is ready.
• Fill the cuvet with 10 mL of unreacted
sample, up to the mark, and replace the
cap.
• Place the cuvet into the holder and ensure
that the notch on the cap is positioned
securely into the groove.
• Press ZERO/SET and “SIP” will blink on the
display.
• After a few seconds the display will show
“-0.0-”. The meter is now zeroed and ready for
measurement.
• Remove the cuvet from the instrument. Remove
the cap.
• Add the content of one packet of
HI 95771A-0 Chlorine Ultra HR reagent A.
• Add the content of one packet of
HI 95771B-0 Chlorine Ultra HR reagent B.
Replace the cap and shake gently for 20
seconds.