LaMotte COD3 Plus, Руководство оператора

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Ammonia Nitrogen
, Low Range COD3 Plus Colorimeter 10.16
subsequent test results of unknown samples. It is necessary to determine the reagent
blank only when a new lot number of reagents is obtained.
PROCEDURE - SALT WATER
1. Press and hold until colorimeter turns on.
2. Press
ENTER
to select
Testing Menu
.
3. Select All Tests (or another sequence containing 007 Ammonia-N LRS ) from
Testing Menu.
4. Scroll to and select 007 Ammonia-N LRS from menu.
5. Rinse a clean tube (0290) with sample water. Fill to the 10 mL line with
sample.
6. Insert tube into chamber, close lid and select Scan Blank . (See Note.)
7. Remove tube from colorimeter. Use the 1.0 mL plastic pipet (0354) to add 2.0 mL
of *Salicylate Ammonia #1 (3978). Cap and mix.
8. Use the 0.15 g spoon (0727) to add two measures of *Salicylate #2 Reagent
(7457). Cap and mix until dissolved. Wait 1 minute.
9. At end of 1 minute waiting period use 0.1 g spoon (0699) to add two measures
of *Salicylate #3 Reagent Powder (7458). Cap and shake vigorously for at least
30 seconds and all solid has dissolved. Wait 20 minutes for maximum color
development.
10. At the end of the 20 minute waiting period, immediately mix and insert tube into
chamber, close lid and select Scan Sample . Record result.
11. Press to turn colorimeter off or press EXIT to exit to a previous menu or
make another menu selection.
CALCULATIONS:
To express results as Unionized Ammonia (NH
3
):
ppm Unionized Ammonia (NH
3
) =
ppm Ammonia-Nitrogen (NH
3
–N) x 1.2
To express results as Ionized Ammonia (NH
4
):
ppm Ionized Ammonia (NH
4
+ ) =
ppm Ammonia-Nitrogen (NH
3
–N) x 1.3
To determine the percentages of Unionized and Ionized Ammonia-Nitrogen, consult
the Appendix.
NOTE: It is strongly suggested that a reagent blank be determined to account for
any contribution to the test result by the reagent system. To determine the reagent
Testing