Hach IntelliCAL ISENH3181 Series User manual

DOC022.53.80107
ISENH3181
05/2021, Edition 6
User Manual

Table of Contents
Section 1 Product overview................................................................................. 3
Section 2 Specifications ...................................................................................... 3
Section 3 Safety information............................................................................... 4
3.1 Intended use ....................................................................................................... 4
3.2 Use of hazard information..................................................................................... 4
3.3 Precautionary labels............................................................................................. 5
3.4 Product hazards.................................................................................................... 5
Section 4 Preparation for use.............................................................................. 5
Section 5 Calibration............................................................................................... 6
5.1 Calibration notes ................................................................................................. 6
5.2 Calibration procedure........................................................................................... 7
Section 6 Sample measurement....................................................................... 8
6.1 Sample measurement notes ............................................................................... 8
6.2 Sample measurement procedure......................................................................... 8
6.3 Interferences ....................................................................................................... 9
Section 7 Verify the calibration.......................................................................... 9
7.1 Verification procedure......................................................................................... 10
Section 8 Maintenance......................................................................................... 10
8.1 Storage............................................................................................................... 10
Section 9 Troubleshooting ............................................................................... 12
9.1 Slope check........................................................................................................ 13
9.2 Standard additions check................................................................................... 13
Section 10 Consumables..................................................................................... 14
10.1 Accessories...................................................................................................... 15
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Table of Contents
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Section 1 Product overview
The Intellical ISENH318 series probes are digital, combination electrodes that measure the ammonia
concentration in wastewater, drinking water and general water samples. The probes have a built-in
temperature sensor, a refillable membrane module and a double-junction reference. The Ammonia
Ionic Strength Adjuster (ISA) increases the solution pH to >11, where ammonium and ammonia are
measured as NH3. A 59-mL bottle of electrode filling solution is supplied with the probe. Refer to
Figure 1.
Figure 1 Probe overview
1 Probe soaker bottle with storage solution 4 Probe body
2 Membrane module protector cap (3x) 5 Electrolyte filling solution
3 Membrane module (3x) 6 Glass electrode and temperature sensor
Section 2 Specifications
Specifications are subject to change without notice.
Specifications Details
Probe type Digital combination gas-sensing ammonia ion selective electrode (ISE)
probe with a refillable outer body, double-junction reference and built-
in temperature sensor
Measurement range 0.01 mg/L (5x10–7 M) to 14,000 mg/L (1 M) as NH3–N
Accuracy ±0.02 mV or 0.05%, whichever is greater
Sample pH range > pH 11 with Ammonia ISA
Reference type Ag/AgCl
Reference junction Double junction (porous PTFE annular ring)
Slope 57 mV/decade (90 to 110% in linear range at 25 °C (77 °F) per
Nernstian theoretical value)
Linear region 0.5 mg/L to 14,000 mg/L as NH3–N
Temperature accuracy ±0.3 °C (±0.54 °F)
Temperature sensor type 30 kΩ NTC thermistor
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Specifications Details
Operating temperature 5 to 50 °C (41 to 122 °F)
Storage temperature 5 to 35 °C (41 to 95 °F)
Minimum sample volume 15 mL
Minimum immersion depth 25.4 mm (1 in.)
Body material (standard) Epoxy
Membrane Replaceable Hach ISENH3181 Ammonia membrane module
Electrolyte filling solution 0.1 M NH4Cl (membrane module)
Reference electrolyte Non-refillable gel reference element
Storage solution Short-term and mid-term storage: 1000 mg/L NH3—N standard
solution
Long-term storage: Hach pH Electrode Storage Solution
Cable connection M12 digital output and connector
Dimensions Diameter: 12 mm (0.47 in.)
Length: 175 mm (6.9 in.) total; 103 mm (4.1 in.) below head
Cable length: ISENH318101: 1 m (3.3 ft); ISENH318103: 3 m (9.8 ft)
Warranty 1 year on the probe. This warranty covers manufacturing defects, but
not improper use or wear.
Certifications CE, FCC/ISED
Section 3 Safety information
3.1 Intended use
The Intellical probes are intended for use by individuals who measure water quality parameters in the
laboratory. The Intellical probes do not treat or alter water.
3.2 Use of hazard information
D A N G E R
Indicates a potentially or imminently hazardous situation which, if not avoided, will result in death or
serious injury.
WARNING
Indicates a potentially or imminently hazardous situation which, if not avoided, could result in death
or serious injury.
CAUTION
Indicates a potentially hazardous situation that may result in minor or moderate injury.
N O T I C E
Indicates a situation which, if not avoided, may cause damage to the instrument. Information that
requires special emphasis.
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3.3 Precautionary labels
Read all labels and tags attached to the instrument. Personal injury or damage to the instrument
could occur if not observed. A symbol on the instrument is referenced in the manual with a
precautionary statement.
Electrical equipment marked with this symbol may not be disposed of in European
domestic or public disposal systems. Return old or end-of-life equipment to the
manufacturer for disposal at no charge to the user.
3.4 Product hazards
CAUTION
Chemical exposure hazard. Obey laboratory safety procedures and wear all of the
personal protective equipment appropriate to the chemicals that are handled. Refer to
the current safety data sheets (MSDS/SDS) for safety protocols.
CAUTION
Chemical exposure hazard. Dispose of chemicals and wastes in accordance with local,
regional and national regulations.
Section 4 Preparation for use
Install a membrane module that contains ammonia electrode filling solution before use.
1. Fill and install the membrane module on the probe. Do not tighten too much. Refer to the
illustrated steps in Figure 2.
Note: Add 12 drops (0.5 mL) of the ammonia electrode filling solution to the membrane module.
2. Condition the probe before use. To condition the probe, soak the probe in a 1000 mg/L NH3—N
standard solution for 30 to 60 minutes. Do not add the ISA to the standard solution.
3. Make sure that the meter has the correct date and time settings. The service-life time stamp in
the probe comes from the date and time settings in the meter.
Note: Some meters automatically open the date and time settings when the meter starts for the first time, or
after battery replacement.
4. Connect the probe to the meter.
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Figure 2 Install the membrane module
Section 5 Calibration
The procedure that follows is applicable to meters that can connect to Intellical ISE probes. Refer to
the applicable meter documentation for meter operation and probe-specific settings.
5.1 Calibration notes
Read the notes that follow before calibration.
• Make sure to install the ammonia membrane module with ammonia electrode filling solution on the
probe.
• Measure the standard solutions from lowest to highest concentration for best results.
• For best results, reset the filling solution after calibration. To reset the filling solution, put the probe
(with installed membrane) in a 1000 mg/L NH3—N standard solution without ISA for 30 seconds to
1 minute.
• Keep all of the solutions (standard solutions and samples) at the same temperature (± 2 °C
(± 3.6 °F)) for best results.
• Stir the standards and samples at a slow and constant rate to prevent the formation of a vortex.
• Use the default calibration options or change the options in the probe settings menu.
• Use the single display mode for calibration when more than one probe is connected to the meter (if
applicable).
• Calibrate the probes and verify the calibration regularly for best results. Use the meter to set
calibration reminders.
• The calibration data is stored in the probe. When a calibrated probe is connected to a different
meter with the same calibration options, a new calibration is not necessary.
• Air bubbles below the sensor when in solution can cause a slow response or error in the
calibration. Make sure to remove air bubbles during calibration.
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5.2 Calibration procedure
1. Go to the
calibrate menu.
Select the probe, if
applicable. The
display shows the
standard solutions to
use for calibration.
2. Add 25 mL of
each standard
solution to different
beakers.
3. Add one
Ammonia Ionic
Strength Adjustor
(ISA) Powder Pillow
to each 25 mL of
standard solution.
Note: As an alternative,
add 0.5 mL of Ammonia
ISA Solution.
4. Add a stir bar to
the first standard
solution. Put the
standard solution on
an electromagnetic
stirrer. Stir at a
moderate rate.
5. Rinse the probe
with deionized water.
Dry the probe with a
lint-free cloth.
6. Put the probe in
the standard solution
with the sensor fully
submerged. Do not
put the probe on the
bottom or sides of
the beaker.
7. Shake the probe
from side to side to
remove air bubbles.
8. Stir for 30 to
60 seconds, then
read the ammonia
concentration of the
standard solution.
9. Do steps 3
through 8 to read the
value of the
remaining standard
solutions.
10. Save the
calibration.
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Section 6 Sample measurement
The procedure that follows is applicable to meters that can connect to Intellical ISE probes. Refer to
the applicable meter documentation for meter operation and probe-specific settings.
6.1 Sample measurement notes
Read the notes that follow before sample measurements.
• Make sure to install the ammonia membrane module with ammonia electrode filling solution on the
probe.
• Rinse the probe with deionized water and dry with a lint-free cloth between measurements to
prevent contamination.
• To measure samples of low concentration after measurements of high concentration, reset the
filling solution for best results. To reset the filling solution, put the probe (with installed membrane)
in a 1000 mg/L NH3—N standard solution without ISA for 30 seconds to 1 minute.
• If the stabilization time is long, try a different stir rate and make sure to condition the probe.
• Keep all of the solutions (standard solutions and samples) at the same temperature (± 2 °C
(± 3.6 °F)) for best results.
• If complete traceability is necessary, enter a sample ID and operator ID before measurement.
Refer to the meter manual for instructions.
• Stir the standards and samples at a slow and constant rate to prevent the formation of a vortex.
• The meter automatically saves the measurement data when the user manually reads each data
point and when the meter is set to read at regular intervals. The user must manually save each
data point when the meter is set to read continuously.
• Air bubbles below the sensor can cause a slow response or error in the measurement. Make sure
to remove air bubbles before and during measurements.
6.2 Sample measurement procedure
1. Pour 25 mL of
fresh sample into a
50‑mL beaker.
2. Add one
Ammonia Ionic
Strength Adjustor
(ISA) Powder Pillow.
Note: As an alternative,
add 0.5 mL of Ammonia
ISA Solution.
3. Add a stir bar.
Put the beaker on an
electromagnetic
stirrer. Stir at a
moderate rate.
4. Rinse the probe
with deionized water.
Dry the probe with a
lint-free cloth.
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