Hanna Instruments HI 96733 User Manual

Page 6

The instructions listed below should be carefully followed during testing to ensure best accuracy.
• Color or suspended matter in large amounts may cause

interference, therefore these should be removed by
treatment with active carbon and by prior filtration.

• For a correct filling of the cuvette: the liquid in the

cuvette forms a concavity on the top; the bottom of this
concavity must be at the same level of the 10 mL mark.

• In order to measure exactly 0.5 mL of reagent with the 1 mL syringe:

(a) push the plunger completely into the syringe and insert the tip into the solution.
(b) pull the plunger up until the lower edge of the seal is exactly on the 0.0 mL mark.
(c) take out the syringe and clean the outside of the syringe tip. Be sure that no drops are

hanging on the tip of the syringe, if so eliminate them. Then, keeping the syringe in
vertical position above the cuvette, push the plunger down into the syringe until the lower
edge of the seal is exactly on the 0.5 mL mark. Now the exact amount of 0.5 mL has
been added to the cuvette, even if the tip still contains some solutio

GENERAL TIPS FOR AN ACCURATE MEASUREMENT

Under range:

A blinking “0.0” indicates that the sample

absorbs less light than the zero reference. Check the procedure
and make sure you use the same cuvette for reference (zero) and
measurement.

Over Range:

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.

c) during calibration procedure

Standard Low:

The standard reading is less than expected.

Standard High:

The standard reading is higher than expected.

Cap error:

Appears when external light enters in the analysis

cell. Assure that the cuvette cap is present.

Cooling lamp:

The instrument waits for the lamp to cool down.

d) other errors and warnings

Battery low:

The battery must be replaced soon.

Dead battery:

This indicates that the battery is dead and must

be replaced. Once this indication is displayed, the meter will
lock up. Change the battery and restart the meter.

(c)

(a)

(b)

Probable level of
liquid taken up
by syringe