Gardner LCM IV User Manual

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Standard programs
The current result of the actual reading and all further 
measurements will be displayed in the selected color scale.
Alternative
1.
Tap the touch-sensitive area Result 
2.
The result is shown in the next color scale in the list.
5.5.1.4 Change the measuring range after a measurement
1.
Tap the touch-sensitive areas for the upper or lower limits of 
the barchart.
2.
Enter the new limit and press OK to confirm. 
Note: The changed measurement range limit is displayed in blue.
Note: It is only possible to change the limits inside the measuring range 
of the color scale. It is not possible to expand the range, e. g. to Hazen 
2000.
The current result and all further measurements will be displayed 
with the new measuring range.
5.5.2 Determination of the iodine color value
DIN 6162 defines the iodine color value as mg iodine per 100 mL 
potassium iodide solution. Color matching with the iodine color 
scale determines the depth of color of clear liquids like solvents, 
plasticisers, resins, oils and fatty acids, whose color is similar to 
that of a solution of iodine and potassium iodide of the same 
thickness.
For iodine color values of less than or approximately 1, the 
determination of the Hazen value according to DIN-ISO 6271 is to 
be preferred. Taking and preparing samples is described in 
Chapter 
The iodine color value can be determined 
with sufficient accuracy using an 11 mm disposable glass round 
cuvette.
5.5.3 Determination of the Hazen color value (Pt-Co or APHA method)
The Hazen color value (ISO 6271, also referred to as the "APHA 
method" or Platinum-Cobalt Scale) is defined as mg platinum per 
1 liter of solution. The Hazen parent solution comprises 1.246 g 
potassium-hexachloroplatinate (IV) and 1.00 g cobalt(II) chloride, 
which is dissolved in 100 mL hydrochloric acid and topped up to 
1000 mL with distilled water.
The Hazen-color scale is used to evaluate the colors of nearly 
water-clear products. It has narrower gradations in the light 
yellow range than the Iodine Color Scale and extends to 
water-clear color casts.
Note: Samples with Hazen values of between 50 and 1000 can be 
measured with sufficient accuracy in 10 mm square and 11 mm round