Hanna Instruments HI 121 User Manual

Instruction Manual

OFF

LOG

CHANNEL

CFM

CAL

Calibration Check

HI 123

pH / mV / ISE Meter

HI 121 & HI 123

pH/mV/ISE/Temperature

Bench Meters

with Calibration Check

www.hannainst.com

Dear Customer, Thank you for choosing a Hanna Instruments product. Please read this instruction manual carefully before using the instruments. This manual will provide you with the necessary information for correct use

of the instruments, as well as a precise idea of their versatility. If you need additional technical information, do not hesitate to e-mail us at

tech@hannainst.com or turn to the back cover for our worldwide contact list. These instruments are in compliance with directives.

WARRANTY

HI 121 and HI 123 are guaranteed for two years against defects in workmanship and materials when used for their intended purpose and maintained according to instructions. Electrodes and probes are guaranteed for six months. This warranty is limited to repair or replacement free of charge.

Damage due to accidents, misuse, tampering or lack of prescribed maintenance is not covered.

If service is required, contact the dealer from whom you purchased the instrument. If under warranty, report the model number, date of purchase, serial number and the nature of the problem. If the repair is not covered by the warranty, you will be notified of the charges incurred. If the instrument is to be returned to Hanna Instruments, first obtain a Returned Goods Authorization number from the Technical Service department and then send it with shipping costs prepaid. When shipping any instrument, make sure it is properly packed for complete protection.

TABLE OF CONTENTS

WARRANTY .................................................................................................................... 2

PRELIMINARY EXAMINATION .......................................................................................... 3

GENERAL DESCRIPTION .................................................................................................. 3

FUNCTIONAL DESCRIPTION HI 121 .................................................................................. 4

FUNCTIONAL DESCRIPTION HI 123 .................................................................................. 5

HI 121 AND HI 123 SPECIFICATIONS ........................................................................... 10

OPERATIONAL GUIDE .................................................................................................... 11

pH CALIBRATION .......................................................................................................... 15

ENHANCED CALIBRATION MESSAGES ............................................................................ 20

ELECTRODE CONDITION & ELECTRODE RESPONSE TIME ................................................. 21

RELATIVE mV CALIBRATION ........................................................................................... 22

ISE CALIBRATION .......................................................................................................... 23

GOOD LABORATORY PRACTICE (GLP) .............................................................................. 25

SETUP ......................................................................................................................... 30

LOGGING ...................................................................................................................... 34

AutoHOLD .................................................................................................................... 38

PRINTING (HI 123 only) ................................................................................................ 39

TEMPERATURE CALIBRATION (for technical personnel only) ........................................... 43

mV CALIBRATION (for technical personnel only) ............................................................ 44

PC INTERFACE .............................................................................................................. 45

pH BUFFER TEMPERATURE DEPENDENCE ..................................................................... 48

ELECTRODE CONDITIONING & MAINTENANCE ................................................................ 49

PRINTER MAINTENANCE (HI 123 only) .......................................................................... 52

TROUBLESHOOTING GUIDE ........................................................................................... 53

TEMPERATURE CORRELATION FOR pH SENSITIVE GLASS ................................................ 55

ACCESSORIES .............................................................................................................. 56

PRELIMINARY EXAMINATION

Remove the instrument from the packing material and examine it carefully to make sure that no damage has occurred during shipping. If there is any damage, notify your Dealer or the nearest Hanna Service Center.

Each instrument is supplied with:

• HI 1131P Glass-body Combination pH Electrode

• HI 7662-T Temperature probe

• pH 4.01 & 7.01 Buffer solutions, 20 mL each

• HI 7071S Electrolyte solution

• 5 paper rolls (HI 123 only)

• 12VDC Power Adapter

• Instruction Manual

Note: Save all packing material until you are sure that the instrument

functions correctly. All defective items must be returned in the original packing with the supplied accessories.

GENERAL DESCRIPTION

The Hanna HI 121 and HI 123 are professional bench meters with two input channels for pH, ORP (Oxidation Reduction Potential), ISE and Temperature measurements with Calibration Check.

Relative mV feature is also provided on both channels. Calibration Check performs a set of diagnostic tests during calibration using

the history of electrode slope and offset to detect problems that can cause loss of accuracy.

Calibration Check Features are:

• Enhanced Calibration Messages

• Electrode Condition on LCD Display

• Electrode Response Time on LCD Display

• Calibration Alarm Time Out

• Out of Calibration Range

Other features include:

• Up to five-point calibration with seven memorized buffers (1.68, 4.01,

6.86, 7.01, 9.18, 10.01 and 12.45 pH) and two custom buffers.

• pH calibration using pH buffers with 0.001 resolution.

• pH reading with manual or automatic temperature compensation.

• Two Log on demand (up to 50 samples) and Autologging (up to 1000 samples) corresponding to each input channel.

• Two selectable alarm limits.

• User selectable AutoLOG modes.

• Printing feature in four selectable languages (HI 123 only).

• Large easy-to-read LCD which shows the pH or ISE, mV and Temperature simultaneously, together with graphic symbols.

• AutoHOLD feature to freeze first stable reading on the LCD.

• GLP feature to view last calibration data for pH, ISE and Relative mV.

• PC interface.

FUNCTIONAL DESCRIPTION

NUMResoIon

RelmVmVpH

AutoLOG

SETGLPAutoHOLD

ON OFF

Front Panel

Primary LCD

Secondary LCD

Electrode Condition

Electrode Response

Rear Panel

678910

RS232POWERTEMPpH/ORPPINISEREF

RCL

LOG

MODE

CHANNEL

CFMCAL

Calibration Check

pH / mV / ISE Meter

HI 121

1) Left Keyboard

2) ON switch

3) OFF switch

4) Right Keyboard

5) Reference input socket for ISE channel

6) BNC electrode connector for ISE channel

7) Pin input socket for pH channel

8) BNC electrode connector for pH channel

9) Temperature probe socket

10) Power adapter socket

11) RS232 serial communication connector

FUNCTIONAL DESCRIPTION

ON OFF

NUMResoIon

RelmVmVpH

AutoLOG

PaperPrintAutoHOLD

Front Panel

Primary LCD

Secondary LCD

Electrode Condition

Electrode Response

Rear Panel

678910

Paper Roll

RS232POWERTEMPpH/ORPPINISEREF

LOG

CHANNELCFMCAL

Calibration Check

HI 123

pH / mV / ISE Meter

HI 123

1) Left Keyboard

2) ON switch

3) OFF switch

4) Right Keyboard

5) Reference input socket for ISE channel

6) BNC electrode connector for ISE channel

7) Pin input socket for pH channel

8) BNC electrode connector for pH channel

9) Temperature probe socket

10) Power adapter socket

11) RS232 serial communication connector

12) Printer

1 2

10 11 12

NUMResolutionISE

RelmVmVpH

AutoLOG

SETGLPAutoHOLD

HI 121 KEYBOARD ON THE LEFT

Shortcuts to alternate functions

1) AutoHOLD key, to freeze the first stable reading on the LCD.

2) GLP key, to display Good Laboratory Practice Information.

3) SET key, to enter/exit SETUP mode.

4) key, to toggle between parameters while in RECALL or SETUP

modifying mode (backwards), to toggle between absolute mV and temperature while in Relative mV mode and between pH buffer and temperature while in pH calibration mode.

5) AutoLOG key, to start/stop AutoLOG mode.

6) key, to toggle between parameters while in RECALL or SETUP

modifying mode (forwards), to toggle between absolute mV and temperature while in Relative mV mode and between pH buffer and temperature while in pH calibration mode.

7) pH key, to select pH channel.

8) mV key, to select mV range.

9) RelmV key, to select Relative mV range.

10) ISE key, to select ISE channel.

11) Resolution key, to select pH resolution.

Numerical keys

10) key, to change sign.

12) NUM key, to activate the numerical keys (0 to 9).

RCL

LOG

MODE

CHANNEL

CFMCAL

Calibration Check

pH / mV / ISE Meter

HI 121

HI 121 MAIN KEYBOARD ON THE RIGHT

1) CAL key, to enter and exit/escape calibration mode.

SET key (second function), to enter/exit SETUP mode.

2) CFM key, to confirm different values.

GLP key (second function), to display Good Laboratory Practice Information.

3) CHANNEL key, to select the measurement input channel, pH or ISE.

CLR key (second function), to clear calibration or logged data.

4) key, to manually increase temperature value or other parameters.

AutoHOLD key (second function), to freeze the first stable reading on the LCD.

5) key, to manually decrease temperature value or other parameters.

AutoLOG key (second function), to start/stop AutoLOG mode.

6) MODE key, to select the measurement unit or to switch focused data.

7) 2nd key, to select second key function.

8) LOG key, to store measured data.

9) RCL key, to enter/exit view logged data mode.

Note: To select second key function, press 2nd and then the desired key.

The “2nd” tag will appear on the LCD until the desired key is pressed. To leave second key function selection, press 2nd again.

1 2

10 11 12

NUMResolutionISE

RelmVmVpH

AutoLOG

PaperPrintAutoHOLD

HI 123 KEYBOARD ON THE LEFT

Shortcuts to alternate functions

1) AutoHOLD key, to freeze the first stable reading on the LCD.

2) Print key, to obtain a printout or to cancel printing.

3) Paper key, to pull out the paper.

4) key, to toggle between parameters while in RECALL or SETUP

modifying mode (backwards), to toggle between absolute mV and temperature while in Relative mV mode and between pH buffer and temperature while in pH calibration mode.

5) AutoLOG key, to start/stop AutoLOG mode.

6) key, to toggle between parameters while in RECALL or SETUP

modifying mode (forwards), to toggle between absolute mV and temperature while in Relative mV mode and between pH buffer and temperature while in pH calibration mode.

7) pH key, to select pH channel.

8) mV key, to select mV range.

9) RelmV key, to select Relative mV range.

10) ISE key, to select ISE channel.

11) Resolution key, to select pH resolution.

Numerical keys

10) key, to change sign.

12) NUM key, to activate the numerical keys (0 to 9).

LOG

CHANNEL

CFMCAL

Calibration Check

HI 123

pH / mV / ISE Meter

HI 123 MAIN KEYBOARD ON THE RIGHT

1) CAL key, to enter and exit/escape calibration mode.

SET key (second function), to enter/exit SETUP mode.

2) CFM key, to confirm different values.

GLP key (second function), to display Good Laboratory Practice Information.

3) CHANNEL key, to select the measurement input channel, pH or ISE.

CLR key (second function), to clear calibration or logged data.

4) key, to manually increase temperature value or other parameters.

AutoHOLD key (second function), to freeze the first stable reading on the LCD.

5) key, to manually decrease temperature value or other parameters.

AutoLOG key (second function), to start/stop AutoLOG mode.

6) MODE key, to select the measurement unit or to switch focused data.

Paper key (second function), to pull out the paper.

7) 2nd key, to select second key function.

8) LOG key, to store measured data.

9) RCL key, to enter/exit view logged data mode.

Print key (second function), to obtain a printout or to cancel printing.

Note: To select second key function, press 2nd and then the desired key.

The “2nd” tag will appear on the LCD until the desired key is pressed. To leave second key function selection, press 2nd again.

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HI 121 AND HI 123

SPECIFICATIONS

OPERATIONAL GUIDE

POWER CONNECTION

Plug the 12 VDC adapter into the power supply socket. Notes: • These instruments use non volatile memory to retain the pH,

mV, Ion, temperature calibrations and all other settings, even when unplugged.

• Make sure a fuse protects the main line.

ELECTRODE AND PROBE CONNECTIONS

For HANNA P type pH or ORP electrodes (with internal reference) connect the electrode’s BNC to the socket on the back of the instrument (#8 on page 4 and 5) and the pin to the appropiate socket (#7 on page 4 and 5).

Notes: • Electrode condition and response information is displayed on the

bar graph gauges during the day the calibration is performed only if HANNA P type (PIN) electrodes are used.

• If the electrode is not recognized as a HANNA P type electrode, the bar graph gauges will blink (25 seconds OFF, 4 seconds ON, full bar graph).

For Ion measurements, connect the electrode’s BNC to the appropiate socket (#6 on page 4 and 5) and the reference (for electrodes with separate reference) to the reference input socket (#5 on page 4 and 5).

For temperature measurements and automatic temperature compensation, connect the temperature probe to the appropriate socket.

INSTRUMENT START-UP

• Turn the instrument on by pressing the ON switch.

• All LCD tags are displayed and a beep is heard while the instrument performs a self test.

• The instrument displays then the date on the primary LCD and the time on the secondary LCD, along with the “Remove protective cap” and “Unscrew electrode refilling cap” messages alternatively blinking. These messages alert the user to follow displayed instructions in order to take proper measurements and to improve electrode response.

• The instrument automatically defaults to pH or mV measurement

CHANNEL

mode, if a HANNA P type pH or ORP electrode is detected.

• If no HANNA P type electrode is detected, the instrument starts in the same range as it was at power off.

pH MEASUREMENTS

Make sure the instrument has been calibrated before taking pH measurements.

• Press CHANNEL to enter pH channel.

Note: To change pH resolution, press MODE or simply

Resolution from the left keyboard.

• Submerge the electrode tip and the temperature probe approximately 4 cm (1½”) into the sample to be tested. Allow time for the electrode to stabilize.

• The pH is displayed on the primary LCD and the temperature on the secondary LCD.

OUT CAL RANGE feature warns the user if the current reading is out of the calibrated area. The calibrated area is that part of the pH range in which the calibration point assures an accurate reading. If the reading is taken out of the calibration area, the “OUT CAL RANGE” message will blink. The calibrated area is calculated in according with the pH resolution used during the reading. To avoid having this message, the calibration points have to be well distributed in the desired measurement range.

If measurements are taken successively in different samples, it is recommended to rinse the electrode thoroughly with deionized water or tap water and then with some of the next sample to prevent cross-contamination and to condition the electrode before immersing it into the sample solution.

The pH reading is affected by temperature. In order to measure the pH accurately, the temperature effect must be compensated for. To use the Automatic Temperature Compensation feature, connect and submerge the HI 7662-T temperature probe into the sample as close as possible to the electrode and wait for a few seconds.

If the temperature of the sample is known, manual temperature compensation can be performed by disconnecting the temperature probe.

The display will then show the default temperature of 25 ºC (77 ºF) or the last temperature reading with the “ºC” (or “ºF”) tag blinking.

The temperature can be adjusted with the ARROW keys or the numerical keypad (from –20.0 ºC to 120.0 ºC or from –4.0 ºF to 248.0 ºF).

Press NUM to change the temperature value with the numerical keys. The “2nd” tag will blink. Press CLR or 2nd then CLR if you want to delete digits of the displayed value. The remaining digits will shift to right. Introduce the desired value. If the value is out of temperature range, a long beep will be heard. Press NUM to confirm the new value or CAL to escape without changing the temperature.

mV/ORP MEASUREMENTS

Oxidation-reduction potential (REDOX) measurements provide the quantification of the oxidizing or reducing power of the tested sample.

To correctly perform a redox measurement, the surface of the ORP electrode must be clean and smooth.

• Press MODE or simply mV from the left keyboard to enter mV range.

• Submerge the tip of the ORP electrode (4 cm/1½”) into the sample to be tested and allow a few seconds for the reading to stabilize.

• The instruments display the mV reading on the primary LCD and the temperature on the secondary LCD, along with “Channel” and “ORP” tags if a Hanna ORP electrode with pin is used.

Note: If an ORP electrode with pin is not detected, “Channel”, “pH” and

“ORP” tags will be displayed on the LCD.

• If the reading is out of range, the closest full-scale value will be displayed blinking on the primary LCD.

RELATIVE mV MEASUREMENTS

To enter Relative mV mode, press MODE or simply RelmV from the left keyboard. The relative mV reading will be displayed on the primary LCD and the current temperature value on the secondary LCD.

Note: Press or from the left keypad to toggle between temperature

and absolute mV reading on the secondary LCD.

The Relative mV reading is equal to the difference between the absolute mV input value and relative mV offset established in the relative mV calibration.

ION MEASUREMENTS

To measure Ion concentration, an independent input channel is provided.

• Press CHANNEL or simply ISE from the left keyboard to select ISE channel.

• Submerge the tip of the ISE electrode 4 cm (1½”) into the sample to be tested and allow a few seconds for the reading to stabilize.

• The instruments display the ppm reading on the primary LCD and the temperature on the secondary LCD.

Note: To view the mV or Rel mV reading on the ISE channel, press MODE

or simply mV/RelmV keys from the left keyboard.

TEMPERATURE MEASUREMENTS

Connect the HI 7662-T temperature probe to the appropri- ate socket. Immerse the temperature probe into the sample and allow the reading on the secondary LCD to stabilize.

Notes: • The temperature can be displayed in Celsius degrees (ºC) or in

Fahrenheit degrees (ºF) (see SETUP for details, page 30).

• Make sure that the temperature probe is in the same sample that is measured (pH or ISE).

pH CALIBRATION

Calibrate the instrument often, especially if high accuracy is required. The instrument should be recalibrated:

• Whenever the pH electrode is replaced.

• At least once a week.

• After testing aggressive chemicals.

• If “CAL DUE” tags are blinking during measurement.

• If “OUT CAL RANGE” message blinks during pH measurement (the measurement range is not covered by current calibration).

PREPARATION

Pour small quantities of the buffer solutions into clean beakers. If possible, use plastic or glass beakers to minimize any EMC interferences.

For accurate calibration and to minimize cross-contamination, use two beakers for each buffer solution. One for rinsing the electrode and one for calibration.

If you are measuring in the acidic range, use pH 7.01 or 6.86 as first buffer and pH 4.01 or 1.68 as second buffer. If you are measuring in the alkaline range, use pH 7.01 or 6.86 as first buffer and pH 10.01/9.18 or 12.45 as second buffer.

For extended range measurements (acidic and alkaline), perform a five-point calibration by selecting five of the available buffers.

PROCEDURE

If 0.001 pH resolution is selected, each selected standard buffer value can be updated in according with the value on the production lot certificate at 25 ºC (77 ºF). Press 2nd then SET key when a standard pH buffer with

0.001 resolution is selected. The buffer value will start blinking and it can

be changed with the ARROW keys in a ±0.020 pH window. Calibration has a choice of 7 memorized buffers: pH 1.68, 4.01, 6.86,

7.01, 9.18, 10.01, 12.45 and 2 custom buffers.

The custom buffers are a special option that allows the user to calibrate in a buffer solution different from a standard one. Up to two custom buffers can be set in SETUP menu (see page 30). When selected during calibration, the “CUSTOM C1” or “CUSTOM C2” tags are displayed on the LCD and the custom buffer value can be changed in a ±1.0 pH window, around the set value.

For accurate measurements it is recommended to perform a five-point calibration. However, at least a two-point calibration is suggested.

The instruments will automatically skip the buffers used during calibration and the buffers which are in a ±0.2 pH window, around one of the calibrated buffers.

All new calibrations will override existing stored calibration data, in a ±0.2

CAL

pH window, at these calibration points. The slopes adjacent to the calibration points will be reevaluated.

If the new calibration point has no correspondence in the existing stored calibration data, it is added to it if this is not full, or the instrument will ask which buffer will be replaced by the current buffer.

If at least a two-point calibration has been performed and an offset correction of the electrode is desired, keeping unchanged the existing slopes, perform a one-point calibration with “OFFS” option selected in SETUP menu. If “Pnt” option is selected, the slopes adjacent to the calibration points will be reevaluated.

FIVE-POINT CALIBRATION

• Immerse the pH electrode and the temperature probe approximately 4 cm (1½”) into a buffer solution of your choice (pH 1.68, 4.01, 6.86, 7.01,

9.18, 10.01, 12.45, custom buffer 1 or 2, if these were set) and stir gently. The temperature probe should be close to the pH electrode.

• Press CAL. The “CLEAR CAL IF NEW ELECTRODE” message will be displayed blinking on the LCD for a few seconds if the instrument was calibrated before and calibration was not cleared.

Press CLR or 2nd then CLR if you are using a new electrode or want to clear calibration history, or wait a few seconds to continue.

Press CAL again or the ARROW keys to skip this message. Note: It is very important to clear calibration history when a new

electrode is used because most errors and warning messages that appear during calibration depend on calibration history.

• The instruments will display the measured pH on the primary LCD and the “7.01” buffer on the secondary LCD, together with “CAL” and “Cal Point 1” tags and “7.01” tag blinking.

• If necessary, press the ARROW keys to select a different buffer value.

• The “ ” tag will blink on the LCD until the reading is stable.

CFM

• When the reading is stable and close to the selected buffer, “CFM” tag blinks.

• Press CFM to confirm calibration.

• The calibrated value is then displayed on the primary LCD and the secondary LCD will display the second expected buffer value, together with “CAL”, “Cal Point 2” and “7.01” tags and the corresponding buffer tag blinking.

• After the first calibration point is confirmed, immerse the pH electrode and the temperature probe approximately 4 cm (1½”) into the second buffer solution and stir gently. The temperature probe should be close to the pH electrode.

• If necessary, press the ARROW keys to select a different buffer value.

• The “ ” tag will blink on the LCD until the reading is stable.

• When the reading is stable and close to the selected buffer, “CFM” tag blinks.

• Press CFM to confirm calibration.

• The calibrated value is then displayed on the primary LCD and the secondary LCD will display the third expected buffer value.

• After the second calibration point is confirmed, immerse the pH electrode and the temperature probe approximately 4 cm (1½”) into the third buffer solution and stir gently. The temperature probe should be close to the pH electrode.

• If necessary, press the ARROW keys to select a different buffer value.

• The “ ” tag will blink on the LCD until the reading is stable.

• When the reading is stable and close to the selected buffer, “CFM” tag blinks.

• Press CFM to confirm calibration.

• The calibrated value is then displayed on the primary LCD and the secondary LCD will display the fourth expected buffer value.

CFM

• After the third calibration point is confirmed, immerse the pH electrode and the

CFM

temperature probe approximately 4 cm (1½”) into the fourth buffer solution and stir gently. The temperature probe should be close to the pH electrode.

• If necessary, press the ARROW keys to select a different buffer value.

• The “ ” tag will blink on the LCD until the reading is stable.

• When the reading is stable and close to the selected buffer, “CFM” tag blinks.

• Press CFM to confirm calibration.

• The calibrated value is then displayed on the primary LCD and the secondary LCD will display the fifth expected buffer value.

• After the fourth calibration point is confirmed, immerse the pH electrode and the temperature probe approximately 4 cm (1½”) into the fifth buffer solution and stir gently. The temperature probe should be close to the pH electrode.

• If necessary, press the ARROW keys to select a different buffer value.

• The “ ” tag will blink on the LCD until the reading is stable.

• When the reading is stable and close to the selected buffer, “CFM” tag blinks.

• Press CFM to confirm calibration.

• The instruments store the calibration values and return to normal measurement mode.

FOUR, THREE or TWO-POINT CALIBRATION

• Proceed as described in “FIVE-POINT CALIBRATION” section.

• Press CAL after the appropriate accepted calibration point. The instruments will return to measurement mode and will memorize the calibration data.

ONE-POINT CALIBRATION

Two SETUP selectable options are available: “Pnt” and “OFFS”. If the “Pnt” option is selected, the adjacent slopes will be reevaluated. If the “OFFS” option is selected, an electrode offset correction is performed

keeping unchanged the existing slopes.

• Proceed as described in “FIVE-POINT CALIBRATION” section.

• Press CAL after the first calibration point was confirmed. The instruments will memorize the one-point calibration data and will return to measurement mode.

Notes: • Press MODE or / from the left keyboard to toggle between

pH buffer and temperature reading during calibration.

• Each time a buffer is confirmed, the new calibration parameters replace the old calibration parameters of the corresponding buffer.

If current confirmed buffer has no correspondence in the existing stored calibration and this is not full, the current buffer is added to the existing stored calibration.

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