Hach-Lange SENSION+ 50, SENSION+ 49 User Manual

DOC022.52.80407

50 49

08/2013, Edition 1

User Manual

Table of Contents

Specifications..............................................................................................................3

General information..................................................................................................3

Safety information........................................................................................................3

Use of hazard information............................................................................................ 3

Precautionary labels....................................................................................................4

Product overview.......................................................................................................4

Meter compatibility....................................................................................................5

Preparation for use....................................................................................................5

Polarize the dissolved oxygen probe................................................................5

Calibration.....................................................................................................................5

Calibration notes..........................................................................................................5

Calibration procedure (pH and conductivity)................................................................ 6

Calibration procedure — DO probe, water-saturated (100%) air................................. 7

Adjust the calibration (manual calibration)...................................................................8

Sample requirements...............................................................................................9

Sample measurement...............................................................................................9

Measurement notes.....................................................................................................9

Measurement procedure............................................................................................ 10

Maintenance...............................................................................................................10

Replace the probes.................................................................................................... 10

Clean the probes.......................................................................................................11

Dissolved oxygen probe............................................................................................12

Clean the probe..................................................................................................12

Replace the membrane module.........................................................................12

Fill the membrane module..................................................................................12

Storage......................................................................................................................13

Rehydrate the pH probe............................................................................................13

Troubleshooting.......................................................................................................13

Troubleshooting notes...............................................................................................15

Examine the probes...................................................................................................15

Replacement parts and accessories...............................................................15

Index...............................................................................................................................17

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Table of Contents

2

Specifications

Specifications are subject to change without notice.

Specification Description

Parameter pH, conductivity and dissolved oxygen (DO)

Measurement range pH: 0 to 14, Conductivity: 5 to 30,000 µS/cm, DO: 0.03 mg/L oxygen to

Temperature sensor Integrated into conductivity sensor

Sensor pH: glass membrane (standard), Conductivity: platinum (platinized),

Reference type (pH) Ag/AgCl

Junction type (pH) Porous pin

Electrolyte pH: Non-refillable gel, DO: Hach electrolyte solution 2759123

Storage solution pH: 3M KCl, Conductivity: distilled water, DO: dry

Number of poles (conductivity sensor) 2

Conductivity cell constant (cm-1) 1.0

Meter compatibility sensION+ MM156 / MM156 DL

Body material Multisensor body: PVC

Length 170 mm

Diameter 40 mm total diameter with 12 mm individual sensors (55 mm diameter

Cable 1.5 m

Connector MP8

1

For use with sensION+ MM156 / MM156 DL portable meters only

saturation, Temperature: 0 to 50 °C (32 to 122 °F)

DO: polarographic with replaceable membrane

Probes body: ABS

Protective shroud: Polycarbonate

with protective shroud installed)

1

General information

In no event will the manufacturer be liable for direct, indirect, special, incidental or consequential
damages resulting from any defect or omission in this manual. The manufacturer reserves the right to
make changes in this manual and the products it describes at any time, without notice or obligation.
Revised editions are found on the manufacturer’s website.

Safety information

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.

Indicates a potentially or imminently hazardous situation which, if not avoided, could result in death or serious
injury.

Indicates a potentially hazardous situation that may result in minor or moderate injury.

W A R N I N G

C A U T I O N

English 3

N O T I C E

Indicates a situation which, if not avoided, may cause damage to the instrument. Information that requires special
emphasis.

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 public disposal
systems after 12 August of 2005. In conformity with European local and national regulations (EU
Directive 2002/96/EC), European electrical equipment users must now return old or end-of-life
equipment to the Producer for disposal at no charge to the user.

Note: For return for recycling, please contact the equipment producer or supplier for instructions on how to return end­of-life equipment, producer-supplied electrical accessories, and all auxiliary items for proper disposal.

Product overview

The 50 49 multisensor is used for pH, conductivity and dissolved oxygen measurements in general
aqueous samples. The 50 49 multisensor has a built-in temperature sensor within the conductivity
probe. Refer to Figure 1. Refer to Sample requirements on page 9 for limitations on use.

The 50 49 multisensor is used with sensION+ meters. Refer to Meter compatibility on page 5.

Figure 1 Product overview

1 Conductivity probe 4 DO polishing cloth 7 Probe storage tube

2 pH probe 5 DO electrolyte (membrane filling

solution)

3 Dissolved oxygen probe 6 Membrane module (DO probe)

8 Protective shroud

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Meter compatibility

The 50 49 multisensor is compatible with the sensION+ handheld meter models: MM156 and
MM156 DL.

Preparation for use

C A U T I O N

Personal injury hazard. Broken glass can cause cuts. Use tools and personal protective equipment to

remove broken glass.

To prepare the probes for calibration or sample measurement:

1. Turn the protective shroud and remove from the multisensor.

2. Turn the probe storage tube(s) and remove from the probe(s). Keep the probe storage tube(s).

3. For conductivity probes: Before initial use, soak the probe sensor in ethanol for 15 seconds.

4. For dissolved oxygen probes: refer to Polarize the dissolved oxygen probe on page 5.

5. Rinse the probe(s) with deionized water. Blot dry with a lint-free cloth.

Polarize the dissolved oxygen probe

Before calibration or measurement of dissolved oxygen with the multisensor, polarize the dissolved
oxygen probe.

The dissolved oxygen probe must be polarized every time the multisensor is disconnected from the
meter or the batteries are removed from the meter. The probe is continuously polarized while it is
connected to the meter.

1. Fill the DO membrane module. Refer to Fill the membrane module on page 12

2. Install the membrane module.

3. Connect the multisensor to the meter. Set the meter to on.

4. Let the dissolved oxygen probe to polarize. Refer to Table 1 for the amount of time.

5. Enter the atmospheric pressure and salinity on the meter. Refer to the meter manual.

Table 1 Polarization times

Disconnect time Polarization time

Less than 5 minutes 10 minutes

5–15 minutes 45 minutes

More than 15 minutes 6 hours

Calibration

Before calibration:

Prepare the probe(s) for use. Refer to Preparation for use on page 5.

Prepare the meter. Refer to the meter manual.

Calibration notes

• For maximum accuracy, calibrate the probe at least once a day.

• Prepare fresh standard solutions for the calibration.

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5

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

• The temperature sensor is within the conductivity probe. Calibration standards must be at same
temperature (ambient temperature is recommended).

• For pH calibration, at least 2 calibration points are necessary.

• For conductivity calibration, use 1-point calibration and select the standard nearest to the expected
measurement range. Refer to the meter manual for other conductivity calibration options.

• Calibration of conductivity cells is important as the conductivity cell constant can change with time.
The calibration identifies the actual cell constant versus the nominal value.

• Do not dilute conductivity standards or samples.

• For dissolved oxygen calibration, a water-saturated air calibration is recommended. Refer to

Calibration procedure — DO probe, water-saturated (100%) air on page 7.

• When the probe is submerged, make sure that there are no air bubbles under the probe sensor
tip(s). Gently shake the probe from side to side to remove any air bubbles.

• Make sure that the reference junction of the pH probe is fully immersed in the solution.

• If the stabilization is slow, shake the multisensor from side to side to stir the solution.

• Always hold the multisensor by the handle. Do not hold by the probe tubes to avoid the heating of
the solutions.

• If a calibration error occurs, refer to Troubleshooting on page 13.

Calibration procedure (pH and conductivity)

1. Connect the

multisensor to the
meter. Set the meter to
on.

Note: For dissolved
oxygen calibration, refer
to Calibration procedure

— DO probe, water­saturated (100%) air

on page 7.

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2. Push Calibrate. The

parameter flashes on
the meter display. Use
the arrow keys to
change the parameter,
if applicable.

3. Push Calibrate to
select the parameter.
The standard flashes
on the meter display.
Use the arrow keys to
select the applicable
standard solution.

Note: pH buffers are
automatically
recognized.

4. Prepare the
standard solutions in
the probe storage
tubes. Add
approximately 6.4 mm
(¼ inch) of standard.

5. Rinse the probe(s)
with deionized water.
Blot dry with a lint-free
cloth.

6. Put the storage tube
in the corresponding
sensor and turn to
tighten.

7. Push Calibrate to
measure the calibration
solution.

8. When the reading is
stable, the meter
prompts for the next
calibration point.
Repeat steps 4–7 for
additional standard
solutions. The
calibration is complete
when the last standard
solution is read. The
meter shows briefly the
message "CAL OK" if
the calibration is
accepted.

Calibration procedure — DO probe, water-saturated (100%) air

1. Set the meter to on.

If the dissolved oxygen
probe is not polarized,
polarize the probe, refer
to Polarize the

dissolved oxygen probe

on page 5.

2. Push Calibrate. The
parameter flashes on
the meter display. Use
the arrow keys to
change the parameter
to DO.

3. Push Calibrate
again to confirm the DO
parameter. "100.0%"
flashes on the meter
display.

Note: The probe can
also be calibrated at
zero oxygen standard.
Use the arrow keys to
select 0% on meter.

4. Rinse the probe(s)
with deionized water.
Blot dry with a lint-free
cloth.

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5. Add approximately

6.4 mm (¼ inch) of

deionized water to the
DO probe storage tube.

6. Invert and shake the
DO probe storage tube
to remove all water
droplets.

7. Immediately put the
DO probe in the storage
tube and turn to tighten.

8. Push Calibrate to
measure the calibration
solution. The calibration
is complete when the
reading is stable. The
meter shows briefly the
message CAL OK if
calibration is accepted.

Adjust the calibration (manual calibration)

A single custom standard value can be specified. Adjust the instrument to read a specified solution
value for pH, DO and conductivity. Use this procedure to calibrate the probe with a single standard
solution.

1. Connect the probe

to the meter. Set the
meter to on.

Note: For dissolved
oxygen calibration,
polarize the probe.
Refer to Polarize the

dissolved oxygen probe

on page 5.

5. Push Read. Wait

until the reading is
stable (stops flashes in
the display).

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2. Rinse the probe with

deionized water. Blot
dry with a lint-free cloth.

6. Push Calibrate. The
parameter flashes on
the meter display. Use
the arrow keys to
change the parameter,
if applicable.

3. Prepare the
standard solution in the
storage tube. Add
approximately 6.4 mm
(¼ inch) of solution.

7. Push and hold
Calibrate, then push
Read. The measured

value flashes. Use the
arrow keys to change
the value.

4. Put the storage tube
in the corresponding
sensor and turn to
tighten.

8. Push Calibrate to
confirm the value. The
meter shows "OK".

Sample requirements

The multisensor probes are not compatible with specific sample types. Probe damage can occur if
used in non-compatible samples.

• Samples should be aqueous. Measurements may be made in partially aqueous or some water­miscible solvents. The results must be interpreted with caution as the full pH scale is shifted when
the solvent system changes.

• The multisensor pH probe is not compatible with solutions that contain silver complexing or binding
agents such as TRIS, proteins and sulfides.

• Proteins can collect on the probe sensors. Make sure the probes stay clean when these types of
samples are measured.

• Do not use multisensor in solutions that are outside the specified temperature range. Refer to

Specifications on page 3.

Sample measurement

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.

N O T I C E

Do not immerse the multisensor if a probe is not connected. Damage to the mini-MP connector will occur.

Before measurement:

Prepare the probe(s) for use. Refer to Preparation for use on page 5.

Calibrate the probe(s). Refer to Calibration on page 5. The manufacturer recommends to calibrate at least once
a day for the best measurement accuracy.

Measurement notes

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

• Do not dilute conductivity standards or samples.

• When the probe is submerged, make sure that there are no air bubbles under the probe tip. Gently
shake the probe from side to side to remove any air bubbles.

• Make sure that the reference junction on the pH probe is fully immersed in the solution.

• If necessary, turn the protective shroud and remove it from the probe. The manufacturer
recommends to measure with the protective shroud installed. The protective shroud prevents
damage to the sensors.

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

• If the stabilization is slow, shake the multisensor from side to side in the solution.

• Do not use probes in areas where EMF is present (i.e., voltaic cells, thermoelectric devices,
electrical generators, resistors and transformers). For use in process units (i.e., spot checking),
make sure that the meter is grounded.

• If a measurement error occurs, refer to Troubleshooting on page 13.

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9

Measurement procedure

1. Connect the

multisensor to the
meter. Set the meter to
on.

Note: Before dissolved
oxygen measurement,
polarize the probe if the
probe is not polarized.

5. Put the protective
shroud on and turn to
tighten.

2. Turn the protective
shroud and remove it
from the multisensor.

6. Put the multisensor
in the sample and stir
with the probes or a stir
stand and stir bar.

3. Turn the probe
storage tubes and
remove the tubes from
the probes.

7. To measure bodies
of water, move the
multisensor up and
down approximately
7-15 cm (3–6 inches) to
circulate the sample
around the probe tips.

4. Rinse the probe(s)
with deionized water.
Blot dry with a lint-free
cloth.

8. Push Read.

9. Repeat steps 4–8 for

additional
measurements.

10. When the
measurements are
done, prepare the
probe for storage. Refer
to Storage
on page 13.

Maintenance

Replace the probes

Each probe of the multisensor has a unique mini-MP connector.

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English

Pull straight to remove or connect the probes. Do not turn the connector. Look to the color coding of
the probe and multisensor connectors. Use the white mark to position the probes in the multisensor
connectors. Refer to Figure 2 for more details.

Figure 2 Replace the probes

1 Blue connector: Dissolved

oxygen probe

2 Green connector: Conductivity

probe

3 Black connector: pH probe

Clean the probes

N O T I C E

Do not rub or touch the tip of the pH or dissolved oxygen sensors.

Clean the probe when there is contamination on the sensor. Symptoms of contamination are:

• Readings are not accurate or consistent.

• The stabilization time is slow.

• A calibration error occurs.

• Contamination is visible on the probe (i.e., dirt).

To clean the dissolved oxygen probe of the multisensor, refer to Dissolved oxygen probe
on page 12.

1. For general contaminants, rinse the probe with deionized water. Blot dry with a lint-free cloth.

2. For other contaminants:

a. Soak the pH and/or conductivity probes of the multisensor in the applicable cleaning agent.

Refer to Table 2.

b. Rinse or soak the sensors for 1 minute in deionized water. Blot dry with a lint-free cloth.

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11

Table 2 Cleaning agent

Contaminant Cleaning agent Soak time

Mineral deposits 0.1 N HCl 5 minutes (maximum)

Fats, grease and oils Warm, mild detergent solution 2 hours (maximum)

Dissolved oxygen probe

Clean the probe

N O T I C E

Use only deionized water and/or the polishing cloth to clean the anode and cathode.

1. Remove the membrane module from the probe:

a. Hold the probe so it is vertical with the tip down.
b. Gently turn the membrane module to remove it from the probe.

2. Soak the membrane module in a mild soap solution.

3. Rinse the membrane module fully with deionized water.

4. Invert the membrane module and shake vigorously to remove any water.

5. Rinse the probe with deionized water. Blot dry with a lint-free cloth.

6. Rub the anode with the polishing cloth supplied. The anode is the outer metallic stem of the probe

that is visible when the membrane module is removed. The polishing cloth removes deposits that
can decrease the probe performance.

7. Fill the membrane module 2/3 full with filling solution and assemble the probe. Refer to Fill the

membrane module on page 12.

Replace the membrane module

Carefully touch the membrane modules to prevent damage.

It is necessary to replace the membrane module periodically. Replace the membrane module when it
is damaged, the probe reading drifts or the probe has a slow response.

Fill the membrane module

Add filling solution to the membrane module if the level of filling solution in the membrane module is
less than 2/3 full.

N O T I C E

1. Remove the membrane module from the probe:

a. Hold the probe so it is vertical with the tip down.
b. Gently turn the membrane module to remove it from the probe.

2. Add filling solution to the membrane module until it is approximately 2/3 full.

3. Install the membrane module on the probe:

a. Carefully tilt the membrane module to remove the air bubbles in the filling solution.
b. Hold the probe with the tip down and slightly tilted.
c. Slowly put the membrane module on the probe. Some filling solution should come out of the

threads of the membrane module. Remove any filling solution on the surface of the probe.

4. If no filling solution comes out of the threads, air may be inside the membrane module cap. Add
more filling solution to the membrane module and repeat step 3.

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English

5. If the probe will be used immediately, polarize the probe. Refer to Polarize the dissolved oxygen

probe on page 5.

6. If the probe will not be used immediately, put the probe in storage. Refer to Storage
on page 13.

Figure 3 Fill the membrane module

1 Anode 2 Cathode 3 Membrane module

Storage

1. Fill the probe storage tube with storage solution to the mark. Refer to Specifications on page 3 for

the applicable storage solution.

2. Put the probe in the storage tube and turn to tighten.

Rehydrate the pH probe

N O T I C E

Do not clean the dissolved oxygen probe of the multisensor with HCl because damage to the membrane will
occur.

If the pH sensor of a probe becomes dry, rehydrate the probe. A dry pH probe will not operate
correctly.

1. Soak the dry probe in a dilute HCl solution for several hours.

2. Rinse the probe with deionized water. Blot dry with a lint-free cloth.

3. Calibrate the probe. Refer to Calibration procedure (pH and conductivity) on page 6.

Troubleshooting

Refer to the table that follows for common problem messages or symptoms, possible causes and
corrective actions.

English

13

Error/Warning Description Solution

Measurement out of range

• Insert the probe into the applicable standard and read again.

• Clean the probes.

• Make sure that there are no air bubbles in the probe's sensors.

• Disconnect the multisensor and then connect the multisensor
again.

• Connect a different probe to make sure if problem is with probe
or meter.

E1 Unstable reading during a

stability measurement or
during calibration.

E2 Probe current: more than

upper limit during
measurement ≥ 250 nA.

pH probe sensitivity out of
range (accepted values
70–105%).

Conductivity calibration
error

E3 Conductivity calibration

error: cell constant is <

0.05 cm-1.

Offset out of range
(accepted values ±58 mV).

E4 Buffer solution not

recognized.

Make sure that the probes are properly immersed in the sample.

• Clean the pH probe and the membrane.

• Make sure that there are no air bubbles in the membrane.

• Make sure that the buffer that is used is specified in
configuration.

• Replace the buffer solution.

• Clean the pH probe.

• Insert the conductivity probe into the applicable standard and
read again.

• Clean the conductivity probe.

• Examine for damage at the conductivity probe sensor, replace
if necessary.

• Insert the conductivity probe into the applicable standard and
read again.

• Clean the conductivity probe.

• Examine for damage at the conductivity probe sensor, replace
if necessary.

• Clean the probe.

• Make sure that there are no air bubbles in the sensors.

• Connect a new probe.

• Clean the probe.

• Make sure that there are no air bubbles in the sensors.

• Make sure that the buffer that is used is specified in
configuration.

• Replace the buffer solution.

• Make sure of the temperature specification in configuration.

Salinity cannot be
calculated TC=0

E5 The standards used for

calibration are identical.

14 English

Change the TC (Temperature Coefficient). Introduce the TC value
at the meter setup to be able to calculate the salinity value. Refer
to meter manual.

• Make sure that the buffer that is used is specified in
configuration.

• Replace the buffer solution.

• Make sure of the temperature specification in configuration.

Error/Warning Description Solution

E6 The calibration solutions

have different
temperatures.

ErA Salinity is set to automatic

and measured value >
50 g/L.

Make sure that the calibration solutions have the same
temperature.

Change the TC value from automatic to the correct value. Refer to
meter manual.

Troubleshooting notes

For the best performance, make sure to:

• Prepare the probe(s) for use before calibration or measurement.

• Obey the calibration and measurement notes.

• Obey the calibration and measurement procedures.

Troubleshooting notes:

• Magnetic stirrers may supply sufficient heat to change solution temperature. Put a piece of
insulating material between the stirrer and beaker.

• Protect the sensing element from direct light during measurement.

• Set the meter to off. Disconnect and then connect the probe again.

• Connect a different probe to identify if the problem is with the probe or the meter.

Refer to Troubleshooting on page 13 for calibration and measurement warnings and errors.

Examine the probes

Note: The lower the sample temperature or the larger the temperature difference between the samples, the longer
the stabilization time will be.

1. Examine the platinized layer of the conductivity probe. Replace the probe if the platinized layer

has been damaged and/or removed.

2. Clean the probes. Replace the DO probe membrane module if necessary.

3. If the DO probe fill solution is contaminated, drain and replace with fresh filling solution.

4. Rinse the pH probe reference junction diaphragm with deionized water. Then, shake the probe

downwards (like a thermometer) to remove any air bubbles in the bulb.

Replacement parts and accessories

Note: Product and Article numbers may vary for some selling regions. Contact the appropriate distributor or refer to
the company website for contact information.

Replacement parts

Description Item no.

pH electrode for 50 49 multisensor LZW9171.99

Conductivity cell for 50 49 multisensor LZW9172.99

DO sensor for 50 49 multisensor LZW9173.99

Handle for 50 49 multisensor LZW9179.99

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Accessories

Description Item no.

Set of 3 x 10 mL printed tubes for portable pH calibration LZW9137.97

Set of 3 x 10 mL printed tubes for portable conductivity calibration LZW9138.99

Electrode storage protector, polypropylene LZW9161.99

Electrode measurement protector, polypropylene LZW9162.99

Tube for DO probe calibration LZW5123.99

Service kit for DO probe (contains two membrane modules and DO filling solution) 5196800

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Tel. [phone]
[phone] (U.S.A. only)
Fax [phone]
[e-mail]
www.hach.com

©

Hach Company/Hach Lange GmbH, 2013.

All rights reserved.

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[e-mail]
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