Hach-Lange PHC108 User Manual

User Manual

PHC108

Safety information

DOC022.52.80428

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.

Specifications

W A R N I N G

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.

C A U T I O N

Personal injury hazard. Glass components can break. Handle with care to prevent cuts.

Specifications are subject to change without notice.

Specifications Details

Probe type Digital combination pH probe with non-refillable polymer electrolyte reference and built-in

temperature sensor

Body material Stainless steel (glass internal)

pH range pH 2 to 12

pH resolution User-selectable stabilization time and resolution—Fast: 0.1, Fast: 0.01, Medium: 0.01, Slow:

0.01 or Slow: 0.001

pH accuracy ±0.02 pH

Sodium (alkalinity) error <0.1 pH at pH >11 in 0.1 M NaCl

Slope –59 mV/pH (85 to 115% at 25 °C (77 °F) per Nernstian theoretical value)

Isopotential point pH 7.00

Temperature compensation 30 kΩ NTC thermistor

Temperature accuracy ±0.3 °C (±0.54 ° F)

Operating temperature 0 to 60 °C (32 to 140 °F)

Storage temperature 5 to 40 °C (41 to 104 °F)

Junction type Ceramic pin + open junctions

Reference type Ag/AgCl

Electrolyte Non-refillable polymer

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Specifications Details

Storage solution 3M KCl + glycerine

Minimum sample depth 15 mm (0.59 in.)

Dimensions Body diameter: 6 mm (0.24 in.)

Body length: 85 mm (3.35 in.)

Total length: 182 mm (7.17 in.)

Cable length: 1 m (3.28 ft)

Cable connection M12 digital output and connector compatible with HQd meters

Product overview

The probe is a digital pH combination electrode with non-refillable electrolyte (polymer), a
stainless steel body and an integrated temperature sensor. The probe is for laboratory
use and has a spear-shaped glass sensor that measures pH in semi-solid media
applications. Refer to Figure 1.

Note: Do not use the probe with organic solvents, low ionic strength or high alkaline sample types.

Figure 1 Probe overview

1 Storage protector 3 Reference junction

2 Cable, 1 meter (3.28 ft) 4 Glass bulb and temperature sensor

Preparation for use

Prepare the probe for use before a calibration or a sample measurement.

1. Turn the storage protector counter-clockwise to loosen the cap.

2. Remove the storage protector from the probe.

3. Fully rinse the reference junction and the glass bulb with deionized water to remove

all of the storage solution or possible salt particles. Dry with a no-lint cloth.

Note: For the best stabilization time, condition the probe for 2 hours in pH buffer 4.01 before use, if
the probe was not used for 3 weeks or more. In low ionic strength (LIS) samples, condition the
probe for a maximum of 5 minutes in the sample before use. In all other cases a condition before
use is not necessary.

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Calibration

Before calibration:

The probe must have the correct service-life time stamp. Set the date and the time in the meter before the probe is attached.

It is not necessary to calibrate again if a calibrated probe is moved from one HQd meter to another. Make sure that the
additional meter is configured to use the same calibration options.

To view the calibration data, push , then select View Probe Data>View Current Calibration.

If two probes are connected, push the UP or DOWN arrow to change to the single display mode to show the Calibrate option
(available only on HQ40d and HQ440d meters).

Prepare the probe for use (refer to Preparation for use on page 2).

Calibration notes:

• Use buffers that are two pH units apart.

• Select additional standard sets with the minimum number of calibration points in the
Calibration Options. For a two-point calibration, select: one buffer with a pH above
and one buffer with a pH below the sample pH. For a one-point calibration, select the
buffer nearest to the sample pH.

• The calibration is recorded in the probe and the data log. Send the calibration to a
PC, a printer or a flash memory stick if connected.

• Use a laboratory stirrer or shake the probe from side to side in the solution to refresh
the reference junction.

• The meter display shows "Stabilizing" and a progress bar as the probe stabilizes in
the standard. The display shows the buffer and the temperature corrected pH value
when the measurement is stable.

• The calibration and sample measurement conditions must be as similar as possible
(e.g., the temperature of the solution, the stir procedure, the stir rate and the position
of the probe).

• If a calibration error occurs, refer to Troubleshooting on page 10.

1. Connect the probe
to the meter. Make
sure that the cable
locking nut is correctly
connected to the
meter. Set the meter
to on.

Calibration procedure:

2. Push Calibrate.

The display shows the
buffers that are
necessary for
calibration.

3. Prepare the fresh
buffers in separate
beakers or applicable
containers.

4. Rinse the probe
with deionized water.
Dry with a no-lint
cloth.

5. Put the probe in
the pH buffer solution
and stir lightly. Make
sure to fully put the
reference junction into
the standard.

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6. Push Read. Wait

until the reading
stabilizes.

7. Do steps 4–6
again to collect the
minimum number of
calibration points
specified in the
calibration options.

Sample requirements

8. Push Done to view

the calibration
summary.

Note: The display will
not show "Done" until
the minimum number
of calibration points is
collected.

9. Push Store to
accept the calibration
and go back to the
measurement mode.

N O T I C E

Some probes are not compatible with specific sample types. Probe damage can occur.

• Do not use the probe in applications where must apply pressure to introduce the
probe into the sample (e.g., solids, viscous samples, samples containing solids, etc.).
For these applications, it is necessary to first open a path with a stainless steel
perforator before inserting the probe.

• Do not use the probe in puncture applications where glass is not permitted.

• Probes with an Ag/AgCl reference system and a single junction are not compatible
with solutions that contain silver complexing or binding agents (e.g., TRIS, proteins
and sulfides). To measure in these solutions, use a double junction probe, a probe
with an Ag+ (silver ion) barrier or a Red Rod* probe.

• Proteins can collect on the sensing element. Make sure that the probe stays clean
when these types of samples are measured.

• Do not use the probe in solutions that are out of the temperature range of the probe.
Refer to Specifications on page 1.

• For low ionic strength (LIS) or high purity samples, use an LIS chamber or a flow cell
to prevent sample contamination.

Measurement

Before measurement:

The probe must have the correct service-life time stamp. Set the date and the time in the meter before the probe is attached.

If the complete traceability is necessary, enter a sample ID and an operator ID before the measurement. Refer to the HQd
meter manual for more information.

A regular calibration is necessary for the best measurement accuracy (refer to Calibration on page 3).

Prepare the probe for use (refer to Preparation for use on page 2).

Measurement notes:

• Data is automatically stored in the data log when Press to Read or Interval is
selected in the Measurement Mode. When Continuous is selected, data is only
stored when Store is pushed.

*

Radiometer Analytical’s Red Rod technology: Encapsulation of reference elements with a red protection tube.

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• For the best stabilization time, condition the probe for several minutes in the sample
or in a solution comparable to the sample in terms of pH and ionic strength before the
initial sample measurement.

• Do not put the probe on the bottom or sides of the container.

• Use a laboratory stirrer or shake the probe from side to side in the solution to refresh
the reference junction.

• The meter display shows "Stabilizing" and a progress bar as the probe stabilizes in
the sample. The display shows the lock icon when the measurement is stable.

• If a measurement error occurs, refer to Troubleshooting on page 10.

Measurement procedure:

1. Connect the probe

to the meter. Make
sure that the cable
locking nut is correctly
connected to the
meter. Set the meter
to on.

6. Do steps 3–5
again to make more
measurements.

2. Condition the
probe in the sample.

7. When
measurements are
done, put the probe in
storage (refer to

Storage

on page 10).

Run Check Standard

3. Rinse the probe

with deionized water
and then with the
sample. Dry with a
no-lint cloth.

4. Put the probe in
the sample and stir
lightly. Make sure to
fully put the reference
junction into the
sample.

5. Push Read. Wait
until the reading
stabilizes.

The Run Check Standard feature validates the instrument performance between sample
measurements. Use the Run Check Standard feature for a periodic or a user-defined
interval measurements of a traceable standard solution. Set the criteria for check
standards from the PHC108 Settings menu.

Note: Access control must be set to off or a valid password must be used to change the Run Check
Standard options.

1. Push . The Full Access Options menu shows.

2. Select Run Check Standard.

Note: Select the correct probe if two probes are connected to the meter.

3. Use the standard solution shown on the display.

4. Rinse the probe with deionized water. Dry the probe with a no-lint cloth.

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