6
Certifi cations:
CE Mark
Safety:
Low Voltage Directive (2006/95/EC)
IEC 61010-1:2001, EN 601010-1:2001,
2nd edition
EU
EMC:
EMC Directive (2004/108/EC)
EN 61326-1:2006, EN 61000-4-2:1995
including A1:1998 and A2:2001, EN
61000-4-3:2002, EN 61000-4-4:2004,
EN 61000-4-5:1995 including A1:2001,
EN 61000-4-6:1996 and A1:2001, EN
61000-4-11:2004, EN 55011:2007, IEC
61000-3-2:2005, EN 61000-3-2:2006,
IEC 61000-3-3:1994, EN 61000-3-3:1995
including A1:2001 and A2:2005
US
EMC
CFR 47, Part 15 Subpart B:2007
CAN
EMC
ICES-003, Issue 4, February 2004
AU/NZ
EMC
AU/NZ: CISPR 11:2004
Weight:
362 g, 13 oz (meter only)
USB Interface:
mini B
STATISTICAL & TECHNICAL DEFINITIONS RELATED TO PRODUCT
SPECIFICATIONS
Method Detection Limit (MDL):
“The method detection limit (MDL) is defi ned as the
minimum concentration of a substance that can be measured and reported with 99%
confi dence that the analyte concentration is greater than zero and is determined from
analysis of a sample in a given matrix containing the analyte.”
1
Note that, “As Dr. William
Horwitz once stated, ‘In almost all cases when dealing with a limit of detection or limit of
determination, the primary purpose of determining that limit is to stay away from it.’”
2
Accuracy:
Accuracy is the nearness of a measurement to the accepted or true value.
3
The accuracy can be expressed as a range, about the true value, in which a measurement
occurs (i.e. ±0.5 ppm). It can also be expressed as the % recovery of a known amount of
analyte in a determination of the analyte (i.e. 103.5 %).
Resolution:
Resolution is the smallest discernible diff erence between any two
measurements that can be made.
4
For meters this is usually how many decimal places are
displayed. (i.e. 0.01). Note that the resolution many change with concentration or range. In
some cases the resolution may be less than the smallest interval, if it is possible to make a
reading that falls between calibration marks. A word of caution, that resolution has very little
relationship to accuracy or precision. The resolution will always be less than the accuracy
or precision but it is not a statistical measure of how well a method of analysis works. The
resolution can be very, very good and the accuracy and precision can be very bad! This is not
a useful measure of the performance of a test method.
Repeatability:
Repeatability is the within-run precision.
5
A run is a single data set, from
set up to clean up. Generally, one run occurs on one day. However, for meter calibrations, a
single calibration is considered a single run or data set, even though it may take 2 or 3 days.
Reproducibility:
Reproducibility is the between-run precision.
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Detection Limit (DL):
The detection limit (DL) for the 2020t/i is defi ned as the minimum
value or concentration that can be determined by the meter, which is greater than zero,
independent of matrix, glassware, and other sample handling sources of error. It is the
detection limit for the optical system of the meter.
