Hach POCKET COLORIMETER II User manual

28838-88
POCKET COLORIMETER™II
ANALYSIS SYSTEMS
INSTRUCTION MANUAL
Free Ammonia
Monochloramine
© Hach Company, 2006. All rights reserved. Printed in the U.S.A. te/dk 9/06 2ed

1—2
Important Note
This manual is intended for use with the following Pocket Colorimeter™ II
instrument:Free Ammonia/Monochloramine Cat. No. 59530-26

1—3
Table of Contents
Instrument Keys and Display.............................................................................1—5
Instrument Cap Cord........................................................................................... 1—6
Nitrogen, Free Ammonia and Chloramine (Mono) ....................................1—9
Measuring Hints .................................................................................................1—9
Interferences......................................................................................................1—18
Color Development Time.................................................................................1—20
Accuracy Check (Monochloramine Test).......................................................1—21
Accuracy Check (Free Ammonia Test)...........................................................1—24
Method Performance........................................................................................1—25
Standard Calibration Adjust Method.............................................................1—25
Summary of Method........................................................................................1—26
Safety.................................................................................................................1—26
Replacement Parts............................................................................................1—27
Instrument Operation.......................................................................................... 2—3
Key Functions.....................................................................................................2—3
Menu Selections..................................................................................................2—4
Switching Ranges............................................................................................... 2—4
Setting the Time .................................................................................................2—4
Recalling Stored Measurements........................................................................2—5
Battery Installation.............................................................................................2—6

1—4
Table of Contents, continued
Error Codes..............................................................................................................2—9
Error Messages ....................................................................................................2—9
Standard Calibration Adjust............................................................................2—13
User-Entered Calibration..................................................................................2—15
Overview............................................................................................................2—15
Calibration Procedure Using Prepared Standards.........................................2—17
Entering a Predetermined Calibration Curve.................................................2—20
Editing a User-entered or Factory Calibration Curve...................................2—22
Exiting the Calibration Routine......................................................................2—24
Deleting Calibration Points..............................................................................2—24
Retrieving the Factory Calibration .................................................................2—25
Maximum/Minimum Displayed Value...........................................................2—26
Certification ...........................................................................................................2—28
How to Order.........................................................................................................2—35
Repair Service.......................................................................................................2—37
Warranty.................................................................................................................2—38

1—5
InstrumentKeysandDisplay
Item Description
1POWER/BACKLIGHT Key
2ZERO/SCROLL Key
3MENU Key
4 Numeric Display
5 Range Indicator
6 Range Indicator
7 Menu Indicator
8 Calibration Adjusted Indicator
9 Battery Low Indicator
10 READ/ENTER Key

1—6
InstrumentCap Cord
The instrument cap for the Pocket Colorimeter™ II doubles as a light shield.
Accurate measurements cannot be obtained unless the sample or blank is covered
with the cap. Use the instrument cap cord to secure the cap to the body of the
colorimeter and prevent loss of the cap. See Figure 1 on page 1—7.
1. Loop the instrument cap cord through the ring on the cap.
2. Remove the battery compartment cover. Press the knotted end of the cord into
the hole indicated by the arrow.
3. Slide the cord into the slot on the battery compartment cover. Snap the cover
into place.

1—7
Instrument Cap Cord, continued
Figure 1 Attaching the Instrument Cap Cord

1—8

1—9
Nitrogen,Free AmmoniaandChloramine (Mono)
(0.04–4.50 mg/L Cl2and 0.02–0.50 mg/L NH3–N)
Indophenol Method* Method 10200
Scope and Application: For finished chloraminated drinking water
Measuring Hints
•Collect samples in clean glass bottles. Results are most reliable from samples
analyzed as soon as possible after collection.
•This method is intended for finished, chloraminated drinking water samples
that have a measurable combined (total) chlorine disinfectant residual.
Sampleswherethedisinfectant residual has disappeared and exhibit a chlorine
demand may produce low ammonia test results. Blanks and ammonia
standards analyzed without a disinfectant residual must be prepared using
high quality, reagent grade water.
•For more accurate chloramine results, determine a reagent blank for each new
lot of reagent using deionized water in place of the sample. Subtract the
reagent blank value from the final chloramine results.
Note: The Pocket Colorimeter™ II is designed to measure solutions contained insample cells. DO
NOT dip the meter in the sample or pour the sample directly into the cell holder.
* U.S. Patent 6,315,950

1—10
Nitrogen, Free Ammonia and Chloramine (Mono), continued
1.Press the POWER key to
turn the meter on.
The arrow should indicate
the monochloramine
channel (Cl2).
Note:
See page 2—4 for
information on selecting the
correct channel.
2.Fill two cells with 10 mL
of sample.
Label one cell “Free
Ammonia” and one cell
“Monochloramine”.
3.Place the cell for
Monochloramine
measurement into the cell
holder.
FA M
M

1—11
Nitrogen, Free Ammonia and Chloramine (Mono), continued
4.Cover the cell with the
instrument cap. 5.Press ZERO/SCROLL.
The display will show
“- - - -” then “0.00”.
Remove the cell from the
cell holder.
6.Add the contents of one
pillow of Monochlor F to
thecell for Monochloramine
measurement.
M

1—12
Nitrogen, Free Ammonia and Chloramine (Mono), continued
7.Cap the cell and shake
for 20 seconds to dissolve
the reagent.
A green color will form if
monochloramine is present.
8.Add one drop of Free
Ammonia Reagent Solution
tothecell for FreeAmmonia
measurement.
9.Cap the reagentbottleto
maintain reagent
performance and stability.
10
mL
5
mL
M
FA

1—13
Nitrogen, Free Ammonia and Chloramine (Mono), continued
10. Cap the cell and mix.
Note:
If the sample becomes
cloudy by the end of the
reaction period, pretreat the
sample and retest. See
Interferences on page 1—18.
11. Wait five minutes.
Note:
Color development
time is dependent on sample
temperature. See Table1on
page 20. for correct times.
12. Place the prepared
Monochloramine sample
into the cell holder.
10
mL
5
mL
FA
HRS MIN SECHRS MIN SEC
M

1—14
Nitrogen, Free Ammonia and Chloramine (Mono), continued
13.Cover the cell with the
instrument cap. 14.Press READ/ENTER.
The results are displayed in
mg/L Monochloramine
(as Cl2).
Leave the cell in the meter.
15.Change the channel.
The arrow will indicate the
free ammonia channel
(NH3–N).

1—15
Nitrogen, Free Ammonia and Chloramine (Mono), continued
16.WIth the
Monochloramine sample
still in the cell holder, press
ZERO/SCROLL.The display
will show 0.00.
Removethesamplecellfrom
the meter.
17.Add the contents of
one pillow of Monochlor F
tothecell for FreeAmmonia
measurement.
Note:
The reaction period
indicated in step 11 on page
13must becompleted before
the addition of Monochlor F
to the cell for free ammonia
measurement
18.Cap and shake for 20
seconds to dissolve the
reagent.
A green color will form if
ammonia or
monochloramine is present.
FA
10
mL
5
mL
FA

1—16
Nitrogen, Free Ammonia and Chloramine (Mono), continued
19.Wait 5 minutes.
Note:
Color development
depends on sample
temperature. See Table 1 on
page 1—20 for correct times.
20.Place the prepared Free
Ammonia sample into the
cell holder.
21. Cover the cell with the
instrument cover.
HRS MIN SECHRS MIN SEC
FA

1—17
Nitrogen, Free Ammonia and Chloramine (Mono), continued
22.Press READ/ENTER.
The results are displayed in
mg/L free ammonia as
nitrogen (NH3–N)
23.Returnthemetertothe
chlorine channel for the
next measurement.

1—18
Nitrogen, Free Ammonia and Chloramine (Mono), continued
Interferences
The following do not interfere in free ammonia determination when at or below
the stated concentration.
Substance Level Tested
Aluminum 0.2 mg/L Al
Chloride 1200 mg/L Cl
Copper 1 mg/L Cu
Iron 0.3 mg/L Fe
Manganese 0.05 mg/L Mn
Nitrate 10 mg/L NO3–N
Nitrite 1 mg/L NO2–N
Phosphate 2 mg/L –PO4
Silica 100 mg/L SiO2
Sulfate 1600 ppm as CaCO3

1—19
Nitrogen, Free Ammonia and Chloramine (Mono), continued
Samples containing high levels of both Total Hardness and Alkalinity may become
cloudy after the addition of the Free Ammonia Reagent Solution. If this occurs by
the end of the first reaction period, the sample for Free Ammonia measurement
must be pretreated as follows:
Note: The sample for Monochloramine measurement does not need pretreatment.
1. Measure 10 mL of sample into the cell for Free Ammonia measurement.
2. Add the contents of one Hardness Treatment Reagent Powder Pillow
(Cat. No. 28823-46) to the sample.
3. Cap the cell and invert until the reagent is dissolved.
4. Remove the cap.
5. Continue with the analysis at step 2using the pretreated sample as the Free
Ammonia cell.
Zinc 5 ppm Zn
Substance Level Tested

1—20
Nitrogen, Free Ammonia and Chloramine (Mono), continued
Color Development Time
Test results are strongly influenced by sample temperature. Both reaction periods
in the procedure are the same and depend on the temperature of the sample.The
reaction periods indicated in the procedure are for a sample temperature of
18-20 °C (64-68 °F). Adjust both reaction periods according to Table 1.
Table 1 Reaction Period
Sample Temperature Reaction Period
(Minutes)
°C °F
54110
7459
9488
10 50 8
12 54 7
14 57 7
16 61 6