Hach PHC729 User manual

DOC022.53.80433
PHC729
05/2021, Edition 2
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.............................................................................................. 7
5.1 Calibration notes................................................................................................... 7
5.2 Calibration procedure........................................................................................... 8
Section 6 Sample measurement ...................................................................... 9
6.1 Sample requirements............................................................................................ 9
6.2 Sample measurement notes................................................................................. 9
6.3 Sample measurement procedure......................................................................... 9
Section 7 Verify the calibration........................................................................ 10
7.1 Verification procedure......................................................................................... 10
Section 8 Maintenance........................................................................................ 11
8.1 Clean the probe.................................................................................................. 11
8.2 Fill the probe....................................................................................................... 12
8.3 Add KCl crystals to the probe............................................................................. 12
8.4 Replace the filling solution.................................................................................. 14
8.5 Soak procedure for dry probes........................................................................... 15
8.6 Storage............................................................................................................... 15
Section 9 Troubleshooting ............................................................................... 16
Section 10 Consumables..................................................................................... 16
10.1 Recommended standards................................................................................. 17
10.2 Accessories...................................................................................................... 18
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Table of Contents
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Section 1 Product overview
The Intellical PHC729 pH probes are digital, combination electrodes with a flat sensing element that
measure the pH of flat surfaces or samples of low depth. The probes use the Red Rod technology
and a saturated KCl electrolyte for high performance. The probes are refillable and have a built-in
temperature sensor. A 59-mL bottle of reference electrolyte filling solution (saturated KCl solution) is
supplied with the probe. Refer to Figure 1.
Note: Do not use the probe to measure the pH of organic solvents, emulsions or samples with many solids. For the
best accuracy, do not use the probe to measure the pH of very alkaline samples.
Figure 1 Probe overview
1 Probe soaker bottle with storage solution 5 Probe soaker bottle holder
2 Filling-hole plug 6 Electrode filling and storage solution
3 Protective tape and filling hole 7 Reference junction
4 Cable 8 Flat sensing element and temperature
sensor
Section 2 Specifications
Specifications are subject to change without notice.
Specifications Details
Probe type Digital combination glass pH probe with refillable electrolyte and built-
in temperature sensor
pH range 0 to 12 pH
pH accuracy ±0.01 pH
Reference type Red Rod (Ag/AgCl in protective tubes)
Reference junction Annular porous ring
Slope –59 mV/pH (85 to 115% at 25 °C (77 °F) per Nernstian theoretical
value)
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Specifications Details
Isopotential point 6.00 pH
Sodium (alkalinity) error <0.3 pH at pH 13 in 0.1 M NaOH
Temperature accuracy ±0.3 °C (±0.54 °F)
Temperature sensor type 30 kΩ NTC thermistor
Operating temperature –10 to 100 °C (14 to 212 °F)
Storage temperature 5 to 40 °C (41 to 104 °F)
Minimum immersion depth <1 mm (<0.04 in.)
Body material Glass
Electrolyte filling solution Saturated KCl
Storage solution Saturated KCl
Cable connection M12 digital output and connector
Dimensions Diameter: 12 mm (0.47 in.)
Length: 200 mm (7.9 in.) total; 103 mm (4.1 in.) below head
Cable length: 1 m (3.3 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 PHC729 probe is intended for use by individuals in the laboratory who measure the pH
of flat surfaces or samples of low depth. The Intellical probes do not treat or alter samples.
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.
CAUTION
Personal injury hazard. Glass components can break. Handle with care to prevent cuts.
Section 4 Preparation for use
N O T I C E
Make sure to remove the protective tape from the filling hole of new probes. A probe with a blocked
filling hole will not operate correctly.
New probes are filled with electrolyte filling solution and have a soaker bottle that contains storage
solution to keep the glass bulb and reference junction hydrated. Prepare the probe for calibration and
measurement as follows.
1. Remove the protective tape from the filling hole. Refer to Figure 2.
Note: Put the soaker bottle on the soaker bottle holder when not in use.
2. Rinse the reference junction and glass bulb with deionized water. Blot dry with a lint-free cloth.
3. If the inner filling solution is low, add more filling solution. Refer to Fill the probe on page 12.
4. If the level of KCl crystals in the probe is less than approximately 0.5 cm (0.2 in.), or for
measurements at high temperatures (> 60 °C (140 °F), add more KCl crystals. Refer to Add KCl
crystals to the probe on page 12.
5. Invert the probe to make sure that the KCl crystals move freely through the liquid. If necessary,
shake the probe to loosen the crystals.
6. Soak the probe in a warm pH 4 buffer solution for approximately 1 hour to condition the probe.
Note: If probe stabilization is slow, soak the probe for 2 hours in a warm pH 4 buffer solution. The soak
procedure helps to dissolve KCl crystals in the reference junction.
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7. 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.
8. Connect the probe to the meter.
9. Remove the filling-hole plug before use. Keep the level of the electrolyte filling solution above the
level of the measurement liquid during use. Refer to Figure 3.
Note: For measurements in low ionic strength (LIS) samples, soak the probe for a maximum of 5 minutes in the
sample before use.
Figure 2 Remove the protective tape
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Figure 3 Probe position during use
1 Filling hole 3 Level of calibration solution
2 Level of electrolyte filling solution 4 Sample surface measurement
Section 5 Calibration
The procedure that follows is applicable to meters that can connect to Intellical pH 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:
• Use prepared pH buffer solutions or mix pH buffer powder pillows with deionized water for
calibration. Discard the prepared buffer solutions after each calibration.
• Use two or three buffer solutions for best results. Two buffer solutions are sufficient if the expected
sample pH is between the pH of the two buffer solutions. The sequence in which the pH buffer
solutions are used is not important. Use buffer solutions that are 2 or more pH units apart.
• For a one-point calibration, use a pH buffer near the expected sample pH.
• 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.
• The pH buffer solutions have known pH values at different temperatures. The meter uses the mV
and temperature readings of the probe in the pH buffer solutions to calculate a calibration slope.
During measurements, the meter adjusts the slope for the sample temperature to determine the
pH value of the sample.
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5.2 Calibration procedure
1. Go to the
calibrate menu.
Select the probe, if
applicable. The
display shows the
pH buffer solutions
to use for calibration.
2. Prepare or pour
the pH buffer
solutions in different
beakers.
3. Open the filling
hole.
4. Rinse the probe
with deionized water.
Dry the probe with a
lint-free cloth.
5. Put the probe in
the first pH buffer
solution. Make sure
that the sensor and
reference junction
are fully in the
solution. Do not put
the probe on the
bottom or sides of
the beaker.
6. Shake the probe
from side to side to
refresh the reference
junction and remove
air bubbles.
Note: Be careful to not
hit the beaker and
damage the probe.
7. Stir slowly, then
read the pH value of
the buffer solution.
The display shows
the temperature-
corrected pH value
when the reading is
stable.
8. Continue with
steps 4 through 7 for
the remaining
buffers or select
Done.
9. Save the
calibration.
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