LaMotte 2020, Instruction Manual

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CALIBRATION
STANDARD SOLUTIONS
The 2020 has been pre-calibrated in the range of 0 to 1100 NTU with AMCO
TM
primary standards manufactured by Advanced Polymer Systems, Inc. This allows
the 2020 to be used for treated water, natural water or wastewater. Recalibration
of the 2020 by the user is not required. However, a procedure to standardize the
calibration should be performed to obtain the most accurate readings over a
narrow range.
Two AMCO
TM
standards of 1.00 NTU and 10.0 NTU are supplied with the 2020.
Standards of other values are available as accessories. The standards are a
suspension of uniformly sized plastic “micro spheres” in ultra pure water, which
require no preparation and are stable for long periods of time. These standards
were manufactured specifically as a reference to calibrate the 2020. Only
LaMotte specific AMCO
TM
standards should be used with the 2020. These
standards are guaranteed to be accurate to within ±1%, if the following
precautions are observed:
u
The standards will remain stable for up to 4 years prior to opening if stored
between 10 and 40°C.
u
Once the seal of the bottle is broken, the stability of the standard is only
guaranteed for 1 year if stored between 10 and 40°C.
u
Never pour any unused or used standard back into the primary standard
bottle.
u
Do not open the bottle in a dusty or dirty environment. Dust and
contaminants from the air can ruin the quality of the standard solutions.
u
Before filling a tube with a standard, rinse the inside of the tube with a small
amount of standard.
u
Cap the standard bottle and the tube immediately after filling.
With proper preparation techniques, freshly prepared Formazin standards should
be equivalent to the AMCO
TM
standards and can be used for meter calibration. A
4000 NTU Formazin Standard is available from LaMotte Company for use in
preparing calibration standards. (See “Optional Accessories,” pg. 6.) Correct
procedures and approved methods for the use of Formazin standards can be found
in the current edition of Standard Methods for Examination of Water and
Wastewater.
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