Hach pH Meter Manual

DOC272.53.80023
User instructions Gel-filled pH electrode: Model PHC10101, PHC10103, PHC10105, PHC10110, PHC10115 or PHC10115
Safety Information

Precautionary LabelsRead all labels and tags attached to the instrument. Personal injury or damage to the instrument could occur if not observed.

OverviewThe PHC101 series electrode is a non-refillable gel-filled combination pH electrode with a built-in temperature sensor (Figure 1 on page 2). The PHC10105, PHC10110, PHC10115 or PHC10130 electrode is available with a 5, 10, 15 or 30 meter cable. The PHC10101 or PHC10103 electrode is available with a 1 or 3 meter cable and is intended for laboratory use. The electrode provides pH measurement in wastewater, drinking water and general applications.

SpecificationsSpecifications are subject to change without notice.

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 end-of-life equipment, producer-supplied electrical accessories, and all auxiliary items for proper disposal.

Specification Details

pH range 2.0 to 14.0 pH

pH resolution (selectable resolution and response time) Fast: 0.1, Medium: 0.01, Slow: 0.001

Slope -59 mV/pH (98 to 103 % at 25 °C per nernstian theoretical value)

Sodium (Alkalinity) error -0.6 pH at pH 12.6 in 1 M NaOH

Temperature range 0.0 to 80.0 °C (32.0 to 176 °F)

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

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

Junction Open junctions

Minimum sample depth 20 mm (0.79 in.)

Reference type Ag/AgCl

Dimensions

Standard: Diameter: 12 mm (0.47 in.), Length: 103 mm (4.056 in.), Total legth: 200 mm (7.9 in.), Cable length: 1 or 3 meter (3.3 or 9.8 ft.). Rugged: Diameter 12 mm (0.47 in.), Length: 20 mm (0.78 in.), Total length: 220 mm (8.7 in.), Cable length: 5, 10, 15 or 30 meter (16.4, 32.8, 49.2, or 98.4 ft.)

Cable connection Digital output and connector compatible with HQd meters

Warranty Sensor is covered by a 6 month warranty

1

Preparation for use1. Remove the locking ring and shroud (rugged model).

2. Remove the tape from the reference junctions and the label from the electrode body. Refer to Figure 1.

3. Remove the electrode storage cap and rinse the electrode with deionized water. Blot dry with a lint-free cloth.

4. Install the shroud and locking ring and hand-tighten (rugged model).

5. If the electrode will not be used immediately, fill the storage cap halfway with Hach Electrode Storage Solution or 3M KCl and install the cap.

Figure 1 Electrode overview1 Shroud (rugged model) 5 Rugged electrode (5, 10, 15 or 30 meter cable)

2 Electrode storage cap 6 Standard electrode (1 or 3 meter cable)

3 Glass bulb and temperature sensor 7 Electrode storage cap holder

4 Reference junctions and tape 8 Locking ring (rugged model)

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Calibration

Calibration notes:

• Probes are initially calibrated at the factory. However, regular calibration by the user is recommended for the best measurement accuracy.

• Additional or custom buffer sets along with the minimum number of calibration points can be selected in the Calibration Options. For a two point calibration, it is recommended that two buffers be selected that bracket the expected sample pH. For a one point calibration, select the buffer nearest to the expected sample pH.

• pH buffers can be used in any order. Use of buffers that are one to three pH units apart is recommended.

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

Note: Procedures also apply for rugged model probes.

Before calibration:

The electrode must have the correct service-life time stamp. Set the date and time in the meter before attaching the electrode.

It is not necessary to recalibrate when moving an electrode from one HQd meter to another if the additional meter is configured to use the same calibration options. If the additional HQd meter uses different calibration options (e.g. calibration standards) or acceptance criteria, calibrate the electrode or change the method settings to select a different method.

To view the current calibration, select the DATA LOG key, View Probe Data, then View Current Calibration.

Tighten the cable locking nut securely when connecting the electrode to the meter.

If a calibration error occurs, recalibrate using fresh, high quality buffers. Refer to Troubleshooting on page 11.

If the glass bulb is or becomes dry, soak the electrode in pH 4 buffer for up to two hours.

If any two probes are connected, Push the UP or DOWN arrow to change to the single display mode in order to show the Calibrate option.

If custom calibration or measurement settings are desired, a new method can be created.

Stir the electrode gently during calibration and measurement. Avoid resting the electrode on the bottom or sides of the container.

1. Connect the electrode to the meter.

2. In three separate beakers or appropriate containers, prepare fresh buffers of 4.0, 7.0 and 10.0 pH.

3. Select Calibrate. The screen will display the current calibration buffer set.

4. Rinse the electrode with distilled water. Place the electrode in a pH buffer and push Read. Stir gently. The display will show Stabilizing... and a progress bar as the electrode stabilizes in the standard.

5. The display will highlight the buffer that has been read and display the temperature corrected pH value. Rinse the electrode with deionized water and the next buffer and put it in the next buffer solution.

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Run check standardThe run check standard feature validates instrument performance between sample measurements. Use the run check standard feature for periodic or user-defined interval measurement of a traceable standard solution. Set the criteria for check standards from the Check Standards Options menu.

Note: Access control must be off or a valid password must be entered before any of the check standard method options can be changed.

1. Select Run Check Standard from the meter Options menu.

Note: Select the appropriate electrode If two electrodes are connected to the meter.

2. Obtain the pH buffer solution specified on the display.

3. Place the electrode in the buffer solution and select Read. The display will show Stabilizing... and a progress bar as the electrode stabilizes in the standard. The display shows the value of the check standard and either Check Standard Passed or Check Standard Failed.

If the display shows Check Standard Passed, the check standard measurement is within the accepted limits defined by the administrative user. Select Done to proceed with sample measurement.

If the display shows Check Standard Failed, the measurement is outside of the accepted limits defined by the administrative user and a recalibration is suggested. If the acceptance criteria is set to Cal Expires on Failure:Yes, the display will show the calibration icon and a question mark until the electrode is recalibrated. Calibrate the electrode to correct the electrode calibration and status indicator (Calibration on page 3).

6. Select Read. 7. Repeat steps 4 to 7 until the minimum number of calibration points specified in the pH method have been acquired.

8. When the minimum number of buffer points are collected, the display will show Done. Continue calibrating with the method specified calibration buffers (up to the maximum number specified in the pH method) until all have been used or select Done to review the calibration summary.

9. The display will show the calibration summary. Select Store to accept the calibration and return to the measurement mode.

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Measurement

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 will only be stored when STORE is selected.

Note: Procedures also apply for rugged model probes.

Before measurement:

The electrode must have the correct service-life time stamp. Set the date and time in the meter before attaching the electrode.

The electrode is factory calibrated and ready for initial use. For applications that require greater accuracy and precision, perform a user calibration (Calibration on page 3). Routine calibrations are required.

Tighten the electrode locking nut securely when connecting the electrode to the meter.

Use deionized water to rinse the electrode clean of any exterior salt deposits before measurement. Blot dry with a lint-free cloth.

If complete traceability is required, enter a sample ID and operator ID before measurement.

Never use this electrode with organic solvents or if the pH to be measured is lower than 2.

For optimal response time, condition the electrode for several minutes in a solution comparable to the sample in terms of pH and ionic strength.

Refer to Troubleshooting on page 11 for measurement errors.

To deploy the rugged probe at a distance, toss the electrode with a gentle underhand throw. Do not swing the electrode by the cable as this may cause injury to the user, will cause severe strain on the cable, and will shorten the service life of the electrode. Damage under these conditions is not covered by the product warranty.

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Maintenance

Short-term storageFor optimal performance, the reference junction must not dry out. Store the electrode in the Hach Electrode Storage Solution or 3M potassium chloride (KCl) solution. The electrode can also be stored between uses for up to 2 hours in a sample (if the sample pH is not extreme).

Long-term storage

• Rinse the electrode with deionized water. Dry the electrode with a lint-free cloth.

• Fill the electrode storage cap halfway with Hach Electrode Storage Solution or 3M potassium chloride (KCl) solution.

• Install the electrode storage cap.Make sure that the storage solution in the cap completely covers the glass bulb and reference junction holes.

Rugged probes may be stored with the shroud installed if the storage container is sufficiently large.

Rugged probe maintenanceThe shroud protects the sensor elements during rugged applications. Damage to the sensing elements can occur if the shroud is not installed during field use. Damage under these conditions is not covered under warranty. Before a rugged probe can be cleaned, the shroud must be removed. Install the shroud after the probe is clean.

1. Prepare the electrode for use ( Preparation for use on page 2).

2. Connect the electrode to the meter. Calibrate the probe if desired or necessary for the application (Calibration on page 3).

3. Rinse the electrode with deionized water and then with the sample. Place the electrode in the sample and stir gently. Select Read. The display will show Stabilizing… and a progress bar as the electrode stabilizes in the sample. The display will then show the lock icon and the temperature compensated result will be automatically stored in the data log.

4. Rinse the electrode with deionized water and blot dry with a lint-free cloth.

5. Repeat steps 3 and 4 for additional measurements. When finished with measurement, rinse the sensor area, blot dry and store vertically in Hach Electrode Storage Solution or 3M KCl.

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To remove the shroud

1. Unscrew the locking ring.

2. Slide the shroud and locking ring off the probe.

To install the shroud

1. Place the locking ring on the probe with the threads toward the glass bulb.

2. Slide the shroud on the probe until it is seated in the locking groove.

3. Firmly tighten the locking ring on the shroud.

To clean the probe

• For general contaminants:

• Rinse the probe with deionized water and blot dry with a lint free cloth.

• Soak the glass bulb for 12 to 16 hours in Hach Electrode Cleaning Solution.

• Rinse or soak for 1 minute in deionized water.

• Soak the electrode in pH 4 buffer for up to 20 minutes, then rinse with deionized water. Blot dry with a lint-free cloth.

• For fats, grease and oils:

• Immerse the glass bulb in a warm detergent solution for up to 2 hours.

• Rinse or soak for 1 minute in deionized water.

• Soak the electrode in pH 4 buffer for up to 20 minutes, then rinse with deionized water. Blot dry with a lint-free cloth.

Advanced operationParameter-specific settings can be changed through the Full Access Options menu. Details about menu navigation, available options and how to change them are given in the screens, tables and procedures throughout this section.

The settings that can be changed are shown in Table 1.

Table 1 Parameter-specific settings

Setting Options

Measurement options • Resolution• Upper and lower range limits (defines pH limits per method)

Calibration options

• Buffer set• Buffer set values (if Custom Buffer Set selected)• Calibration reminder• Minimum Cal points• Slope limit

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Change measurement optionsMethods are groups of default or user defined settings relevant to specific applications. If the meter is set to the default method and the Modify Current Settings option is chosen, a prompt will display to name the method after changes are entered. The settings are saved with this name to distinguish them from the default method settings, which cannot be changed. A saved method can be used instead of repeatedly adjusting individual settings. Changes made to a user defined method are automatically saved with the existing name. Multiple methods can be saved for the same probe.

1. Make sure an electrode is connected to the meter.

2. Push the METER OPTIONS key and select (Probe Model) Settings.

3. Select Modify Current Settings.

4. Select Units to change the units to pH (default) or to mV.

Note: The mV option can be used to find the electrode offset in a pH 7 buffer or to measure the slope. Both units are shown when the detail display mode is selected.

5. Select Measurement Options.

6. Update the settings. Refer to Table 2.

7. If prompted, enter a name for the new method settings. Additional changes made to the settings of an existing method are automatically saved with the same method name.

8. Push EXIT until the meter returns to the measurement mode.

Check standard options

• Standard (temperature compensated buffer or custom at 25 ºC)• Check standard reminder• Acceptance criteria• Standard value (at 25 ºC if custom standard selected)

Units • pH• mV

Table 1 Parameter-specific settings

Setting Options

Table 2 Measurement options settings

Setting Options Description

Resolution

0.1 pH—Fast0.01 pH—Fast0.01 pH—Medium (default)0.01 pH—Slow0.001 pH—Slow

The resolution affects the number of decimal places andthe stabilization time. Higher resolution measurementstake more time to stabilize.

Measurement limitsLower limit (default: 2.00)Upper limit (default: 14.00pH)

The measurement limits can be set to match theacceptable values for the sample.When the measurementis above the upper limit setting or below the lower limitsetting, the meter will show an "Out of limits" message.This message is an alert to a potential problemwith process conditions.

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Change calibration options


2. Push the METER OPTIONS key and select (PHC101) Settings.


4. Select Calibration Options.


Table 3 Calibration options settings

Settings Option Description

Buffer set

Color Coded - 4.01, 7.00, 10.01IUPAC - 4.01, 7.00, 10.01, 12.45DIN - 4.65, 9.23IUPAC - 4.01, 6.86, 10.01, 12.45IUPAC - 4.01, 6.86, 9.18, 12.45IUPAC - 4.01, 7.00, 9.18, 12.45Custom Buffer Set (refer to Table 4)Note: Only the minimum cal points must be satisfied for the DONE key to appear on the calibration screen.

Buffer sets used for calibration that are temperature compensated for calibration. Buffer set values will appear on Calibration Options screen.Custom buffer sets are characterized at 25 °C. A custom buffer can also be chosen by selecting Custom Buffer.

Calibration reminder

Reminder repeat: Off, 2 h, 4 h, 8 h, 2 d, 5 d, 7dExpires: Immediately, Reminder + 30 min, Reminder + 1 hr, Reminder + 2 hr, Continue Reading

The meter can be set to make an audible sound when calibration is due.Calibration expires after a specified time.Note: The meter cannot be used to read samples after calibration has expired unless Continue Reading is selected.

Minimum cal points Minimum calibration points: 1, 2 or 3Number of minimum calibration points required before calibration can be completed.

Slope limit Range: 1% to 10% (acceptable calibration slope criteria)

Slope must fall within set limits for successful calibration. A narrow tolerance gives a more accurate calibration.

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6. Additional changes made to the settings of an existing method are automatically saved with the same method name.


Change check standard options


2. Push the METER OPTIONS key and select (PHC101) Settings.


4. Select Calibration Options.


Table 4 Custom buffer set

Buffer set values

Option Description

Std1Std2Std3Std4Std5

4.65pH - 25 °C

Pre-set temperature compensated buffer values.Note: Selected standards must differ by a minimum of 2 pH units. For example, if 4.65 pH is chosen for the first standard, the second standard must differ by at least 2 pH. Standards that do not meet this minimum will appear gray on the screen and will not be selectable.

6.86pH - 25 °C

7.00pH - 25 °C

4.65pH - 25 °C

9.18pH - 25 °C

9.23pH - 25 °C

10.01pH - 25 °C

12.45pH - 25 °C

Custom Buffer

Custom buffer value.Range = 2.000pH to 14.000pH. Custom buffer values are not temperature compensated. Custom buffers should be read at 25 °C.

No Buffer Standard is undefined when this option is selected.

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6. If prompted, enter a name for the new method settings. Additional changes made to the settings of an existing method are automatically saved with the same method name.


Table 5 Check standard options settings

Settings Options Description

STANDARD

4.01pH - 25 ºC4.65pH - 25 ºC6.86pH - 25 ºC7.00pH - 25 ºC9.18pH - 25 ºC9.23pH - 25 ºC10.01pH - 25 ºC12.45pH - 25 ºC

Temperature compensated buffer value for check standard.

Custom

Buffer value for check standard. Standard value will appear on Check Standard Options screen. No temperature compensation for custom buffers.

CHECK STANDARD REMINDER Reminder: On or OffAllow Defer:Yes or No

Turn reminder on or off Allow Deferment of check standard reminders

Acceptance Criteria Acceptance Limits: ±0.000pHCal Expires on Failure:Yes or No

Set tolerance limits for check standard. Recalibration required if check standard fails

Standard value Enter standard value using up/down arrow keys For custom check standard only

TroubleshootingMessage or symptom

Possible cause Action

Probe not supportedSoftware not updated

Update the HQd software to the newest revision at www.hach.com/SoftwareDownloads. Refer to the HQd Series Meter Manual.

HQd meter does not support IntelliCAL probe. Contact a Hach Technical Support Representative.

Connect a probe or Probe requires service

Electrode not connected properly Disconnect, then connect the electrode. Tighten the locking nut.

Software not updated Update the HQd software to the newest revision at www.hach.com/SoftwareDownloads.

Damaged electrodeVerify connectivity with another electrode or meter to confirm isolated issue with the electrode. Contact a Hach Technical Representative.

Large number of methods stored on probe.

Continue to let probe connect. Do not disconnect probe. Refer to the HQd Series Meter manual.

Standard not recognized error

Tape not removed from the reference junctions

Remove the tape.

Storage cap not removed. Remove storage cap.

Incorrect or contaminated buffer solution

Use fresh buffer solution as specified inthe method.

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http://www.hach.com/SoftwareDownloads




pH reading and/or mV reading is same for all solutions

Tape not removed from the reference junctions Remove the tape.

Storage cap not removed Remove the storage cap.

Electrical issue Contact a Hach Technical Support Representative.

Slow response time

Tape not removed from the reference junctions Remove the tape.

Contaminated glass sensor Clean the electrode.

Electrode not prepared for sample For optimum response time, soak the electrode in sample for 10 to 15 minutes prior to sample measurement.

Low sample temperature or temperature difference between samples.

Check the sample temperature. The lower the temperature or the greater the difference of temperatures between samples, traditionally the longer the response time.

Drifting/Inaccurate readings

Contaminated glass sensor Clean the electrode.

CO2 absorption (For Low Ionic Strength or High Purity sample)

Use the LIS chamber for LIS/high purity samples to prevent sample contamination

Air bubbles around innter reference electrode

Rinse reference junction holes with deionized water thoroughly and gently tap the electrode with hand or shake the electrode down to remove any air bubbles.

Improper storage conditions (discolored, contaminated gel or dried out gel).

Clean or condition the electrode and attempt recalibration.The electrode may not function correctly if the electrode has been left dry for extended periods of time. Attempt to recondition the glass sensor and reference junctions:1) Soak the electrode tip in the 4.01, 7.00 and 10.01 buffers each for 5 minutes.2) Repeat an additional 2x for each buffer.3) Soak the electrode tip in a 3.0 M KCl storage solution for 1-2 hours. Rinse with deionized water prior to use.

Electromagnetic Forces (EMF) such as voltaic cells, thermoelectric devices, eletrical generators, resistors and transformers.

Avoid testing in areas where EMF is present. For testing in process units (i.e. spot checking), make sure the equipment is grounded.

Out of range Measurement value is outside of range Verify that the sample is within the range of the electrode.

Temperature out of range

Temperature value is outside of range

Verify that the sample temperature is within the range of the probe using an external thermometer.

Verify that the temperature sensor is working correctly using an external thermometer.

Measured pH buffer temperature is outside range of the electrode

Verify that the standard temperature is within the range of the electrode.

Verify that the temperature sensor is working correctly.

Check standard temperature value is outside of range

Verify that the Check Standard temperature is within the range of the probe.

Out of limits

Measurement value is outside of measurement limits set in the current method

Verify that the sample is within the limits of the current method.

Create a new method with expanded limits.

Check standard value is outside of limits set in the current method

Verify that the check standard is within the limits of the current method.

Create another method that expands the acceptable limits.

Slope out of rangeSlope exceeds the criteria for % of theoretical (as defined in the method slope limit)

Recalibrate using freshly prepared pH buffers.

Clean the electrode and recalibrate.

Troubleshooting (continued)Message or symptom

Possible cause Action

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Parts

Description Quantity Item Number

IntelliCAL pH gel electrode, standard, 1 m cable 1 PHC10101

IntelliCAL pH gel electrode, standard, 3 m cable 1 PHC10103

IntelliCAL pH gel electrode, rugged, 5 m cable 1 PHC10105




Accessories Description Quantity Item Number

Citizen PD-24 USB handy printer, 120-220 VAC 1 2960100

Color coded probe clips (5 color coded sets) 10/pkg 5818400

Low Ionic Strength (LIS) chamber 1 5189900

Meter stand 1 4754900

Printer paper for PD-24, thermal 5/pk 5836000

Protective glove kit for HQd meters 1 5828700

Protective glove, meter 1 5828700

USB and AC power adapter for HQd meters (included w/HQ40d) 1 5826300

USB keyboard for HQd meters (must have 5826300) 1 LZV582

Rugged electrode accessoriesProbe depth marker (rugged cable markers) 1 5828610

Rugged field case for 2 probes with up to 5 m cables (10 m total) Includes: Empty case and insert for meter and probe storage, (4) containers for sample collection

1 8505500

Rugged field case for three probes with up to 5 m cables (15 m total) Includes same accessories as case 8505500.

1 8505501

Rugged field case for probes with > 5 meter cables (30 m total) Includes: Empty case and insert for meter and two probe storage cavities, space for storage of HQd meter with protective glove

1 8505600

Standard electrode accessoriesField kit (Includes glove kit and 5 120 mL sample cups) 1 5825800

Probe holder for HQd meter (IntelliCAL standard models only) 1 5829400

IntelliCAL probe stand (for standard conductivity cell) 1 8506600

ConsumablesDescription Quantity Item Number

Electrode cleaning solution 500 mL 2965249

Electrode storage cap 5/pkg 5857305

Electrode storage cap lid 1 5829800

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Hach electrode storage solution 1 2756549

Color-coded pH standards (buffers)

pH 4.01 ±0.02 at 25 °C, 500 mL 1 2283449

pH 7.00 ±0.02 at 25 °C, 500 mL 1 2283549

pH 10.01 ±0.02 at 25 °C, 500 mL 1 2283649

pH 4.01 ±0.02 at 25 °C, 4 L 1 2283456

pH 7.00 ±0.02 at 25 °C, 4 L 1 2283556

pH 10.01 ±0.02 at 25 °C, 4 L 1 2283656

pH 4.01 ±0.02 at 25 °C, 20 L 1 2283461

pH 7.00 ±0.02 at 25 °C, 20 L 1 2283561

pH 10.01 ±0.02 at 25 °C, 20 L 1 2283661

IUPAC series certified pH standards (buffers)1

pH 4.005 ± 0.010 at 25 °C, 500 mL 1 S11M002

pH 7.000 (Radiometer Analytical) ± 0.010 at 25 °C, 500 mL 1 S11M004

pH 10.012 ± 0.010 at 25 °C, 500 mL 1 S11M007

pH 6.865 ± 0.010 at 25 °C, 500 mL 1 S11M003

pH 9.180 ± 0.010 at 25 °C, 500 mL 1 S11M006

pH 12.45 ± 0.05 at 25 °C, 500 mL 1 S11M008

Technical grade pH standards (buffers)

pH 4.65 at 25 °C, 500 mL 1 S11M010

pH 9.23 at 25 °C, 500 mL 1 S11M011

1 Certified standards ship with certificates for traceability to Standard Reference Materials

Consumables (continued)Description Quantity Item Number

HACH Company World HeadquartersP.O. Box 389Loveland, Colorado 80539-0389 U.S.A. International customers:Tel (800) -227-4224 (U.S.A. only) Tel +001 (970) 669-3050Fax (970) 669-2932 Fax +001 (970) [email protected] • www.hach.com [email protected]

© Hach Company,2009. All rights reserved. Printed in the U.S.A. Edition 1, May 2009

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Hach pH Meter Manual