Hanna Instruments HI 95711 - Manual (Page 11)

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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.
• 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.
• Proper use of the powder reagent packet:
(a) use scissors to open the powder packet;
(b) push the edges of the packet to form a spout;
(c) pour out the content of the packet.
(a) (b) (c)
GENERAL TIPS FOR AN ACCURATE MEASUREMENT
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• Select the parameter code for free chlorine “701”
ot total chlorine “711” by holding ZERO/SET
(see pag. 13).
• 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.
• Add the content of one packet of the specific
test reagent, for:
Free Chlorine: Total Chlorine:
1 packet of 1 packet of
HI 93701-0 HI 93711-0
• Replace the cap and shake gently for 20 seconds
(or 2 minutes in case of seawater analysis)
• Replace the cuvet into the holder and ensure
that the notch on the cap is positioned securely
into the groove.
or
MEASUREMENT PROCEDURE