Actron E20CP-III, Руководство по эксплуатации

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VIII. IMPROVING ANALYTICAL ACCURACY AND REPEATABILITY
Sample Temperature
Samples should always be analyzed at or very close to room temperature. Never evaluate a hot or warm product,
as this will affect the score.
Grind Specification
The grind coarseness / fineness will affect the amount of surface area that the analyzer sees. It is important to
have a grind similar to the CBC standard for auto-drip:
WEIGHT OF COFFEE RETAINED ON SCREEN #10 & #14 (1168 - 1651 Microns): 03.5%
(00.0% - 03.5%)
WEIGHT OF COFFEE RETAINED ON SCREEN #20 & #28 (589 - 833 Microns): 71.5%
(65.0% - 75.0%)
WEIGHT OF COFFEE PASSING THROUGH SCREEN #28 (Smaller than 589 Microns): 25.0%
(25.0% - 35.0%)
If you do not have access to screens, you can adjust the grind by observing the surface of the coffee during
sample preparation. When the particles plow (form waves) during a second-pass of troweling, the grind is too
coarse. If the surface compacts, compresses and cakes, the grind is too fine. Remember, what looks like an
identical surface to the eye may appear quite different to the analyzer.
Time from Roasting / Cooling / Grinding to Analysis
Once coffee is roasted it begins to decompose. Since the E20CP-III is a system based on chemistry analysis, it
will see the change of decomposition much in the same way you taste it in the cup. A sample’s score can change
(lower) as much as 4 points in 24 hours.
To eliminate this variable, it is important to analyze samples as soon as possible after roasting /cooling. Within
15 minutes is preferable.
NOTE: The drawer must be closed within 30 seconds to read the sample or the calibration will time-out and the
analyzer will not take a reading. If this occurs you must fully close and then fully open the sample drawer to
allow the unit to recalibrate.
Analyzer & Calibration Disk Recertification
The calibration disk set must be periodically re-certified to maintain analyzer accuracy
See Page 21: E20CP-III ANALYZER & CALIBRATION DISK RECERTIFICATION