LaMotte pH Meter User Manual

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PREFACE
This manual serves to explain the use of the pH 5 PLUS meter. This manual functions in two ways: fi rst as a step by step guide to
the meter as possible. If there are questions about the use of this meter contact the LaMotte Tech Service Department.
LaMotte Company will not accept any responsibility for damage or malfunction to the meter caused by improper use of the instrument.
The information presented in this manual is subject to change without notice as improvements are made, and does not represent a commitment on the part of LaMotte Company.
WARNING! This set contains chemicals that may be harmful if misused. Read cautions on
individual containers carefully. Not to be used by
children except under adult supervision.
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TABLE OF CONTENTS
1. INTRODUCTION 5
2. GETTING STARTED 6
2.1 Description of Keypad Functions 7
2.2 Description of LCD Annunciators 7
2.3 Inserting & Removing the Rubber Boot/Stand 8
2.4 Inserting New Batteries 8
2.5 Battery Replacement 8
2.6 Connecting the Electrode and Temperature Sensor 9
2.7 Conditioning the pH Electrode 9
2.8 Switching the Meter On 10
3. CALIBRATION 10
3.1 pH Calibration 10
3.1.1 pH Calibration Procedure 11
3.1.2 Changing the pH Buffer Group 12
3.1.3 Resetting User Calibrated Values 13
3.2 Temperature Calibration 13
3.2.1 With Temperature Probe 13
3.2.2 Without Temperature Probe (no ATC) 14
4. MEASUREMENT 15
4.1 Taking Measurements 15
4.2 Holding a Reading 15
4.3 Releasing a Held Reading 15
5. ELECTRODE CARE AND MAINTENANCE 16
6. TROUBLESHOOTING 16
7. SPECIFICATIONS 17
8. REPLACEMENT PARTS AND ACCESSORIES 18
9. WARRANTY 18
10. RETURN OF ITEMS 19
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1. INTRODUCTION
The pH 5 PLUS microprocessor-based handheld meter is economical and easy to use. It has a large custom LCD (Liquid Crystal Display) for clear and easy reading. The pH 5 PLUS measures pH and temperature (°C).
Meters include 4 alkaline “AAA” batteries, a rubber boot /stand, instruction manual, and warranty card. Please refer to Section 8 Replacement Parts and Accessories for information on additional accessories and calibration solutions.
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2. GETTING STARTED
2.1 Description of Keypad Functions
The pH 5 PLUS has four keys on the splash-proof keypad: ON/OFF, HOLD/ENTER, CAL and MODE/INC.
ON/OFF
MODE/INC
CAL
HOLD
ENTER
Powers meter on and off. Meter starts up in the mode that was last used.
Increments values during temperature calibration mode.
Allows calibration for pH or Temperature, or to abort calibration and return to measure without confi rming a value.
Freezes the measured reading for easy viewing. Confi rms calibration value.
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2.2 Description of LCD Annunciators
The large custom LCD consists of 3½-digit segments which uses annunciators for pH or °C (Temperature). Other annunciators include “HO” (when HOLD function is activated) and “LO” (low battery condition).
2.3 Inserting & Removing the Rubber Boot/Stand
1. To remove the meter from the rubber boot, push out the bottom edge of the meter until it is completely out of the boot. Ensure that the probe cables are not connected. See Figure 1.
2. To insert the meter into the rubber boot, slide in the top of the meter before pushing the bottom edge of the meter down to set it into position. Lift up the stand at the back of the meter for bench top applications. Figure 2.
Figure 1 Figure 2
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2.4 Inserting New Batteries
The battery compartment is found at the back of the instrument. To open the battery compartment, push the cover in the direction of the arrow and lift up. Note the polarity of the batteries before inserting them into position. After the batteries have been replaced, reposition the cover and press down until it locks.
2.5 Battery Replacement
The “LO” annunciator on the LCD alerts when battery power is running low.
Caution: Power off the meter before changing battery.
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2.6 Connecting the Electrode and Temperature Sensor
To connect the probe to the meter, align the BNC connector slots with the posts of the meter socket and rotate the connector clockwise until it locks. Do not force the connector. To remove the probe, rotate the connector in a counter-clockwise direction until it unlocks, and slide the connector off the socket.
BNC connector pH probe
2.5 mm mini phono jack for temperature sensor
Insert the mini phono jack of the temperature sensor into the socket on the meter. Unplug the phono jack when not in use or when measuring pH without temperature compensation.
2.7 Conditioning the pH Electrode
For best results condition the pH probe before the fi rst use, or if it has not been used for a long time, by soaking it in pH 4 buffer solution for at least 1 hour. Rinse before use.
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2.8 Switching the Meter On
1. Press the ON/OFF key. All LCD segments will display momentarily as the meter performs a self-diagnostic test. The meter will display “- - -“ if the meter has not been calibrated or if the meter has been reset.
2. Press the MODE key to choose the desired measurement mode.
3. If a temperature probe is not connected, either 25.0°C (factory default) or the last calibrated temperature value will be displayed. If a temperature probe is connected, the current measured temperature will be displayed.
4. “Or” (Over range) indicates the reading exceeds the maximum measurement range.
Ur” (Under range) indicates the reading is under the minimum measurement range (see Section 7 Specifi cations).
3. CALIBRATION
3.1 pH Calibration
The meter is capable of calibrating up to 3 pH values using USA or NIST (nSt) pH buffer standards or 2 pH values with Low Ionic (Pb) pH buffer standard. All new calibration values will automatically override existing data.
USA group 4.01, 7.00, 10.01
NIST group 4.01, 6.86, 9.18
Pb group 4.10, 6.97
For the best results perform at least a 2-point calibration at room temperature (25 °C) using standard buffers. Begin with pH 7.00 (USA group), pH 6.86 (NIST group) or pH 6.97 (Pb group).
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For a 1-point calibration, the calibration should be performed with a pH buffer value closest to the expected sample value being measured.
The meter has automatic buffer recognition that identifi es the correct pH buffer values during the calibration. The meter will accept calibration values that are within ±1.0 pH units of the expected value, otherwise the DISPLAY will fl ash “Er1” and the value will not be accepted. Press CAL to abort the calibration and return to the measurement mode.
Always use new pH buffer solutions for calibration. Do not reuse buffer solutions that may be contaminated and affect the calibration and accuracy of the measurements. Promptly seal containers and store solutions in a dark, dry, cool environment.
Before use, remove the plastic protective cap on the pH probe and condition the glass bulb by soaking it in tap water or pH buffer (preferably pH 4) for 1-2 hours. This will hydrate the glass bulb if the probe is too dry or if it has not been used recently. Always rinse the probe with clean water before and after each calibration or sample measurement to avoid cross-contamination. For details refer to Section 5 on Probe Care and Maintenance.
3.1.1 pH Calibration Procedure
1. Pour a known pH buffer calibration standard solution, e.g. pH
7.00, into a clean, dry container. Turn on the meter and select the pH mode by pressing the MODE key.
2. Dip the pH probe and temperature probe into the solution. Stir gently and wait for the reading to stabilize (approximately 30 seconds depending on the probe condition).
3. Press CAL to enter the pH calibration mode. “CA” will be displayed momentarily before the display will fl ash the current un-calibrated reading.
4. To abort or cancel the calibration without accepting the new value, press the CAL key. The meter will automatically revert to the pH measurement mode.
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5. Allow the reading to stabilize. Press the ENTER key to confi rm the calibration. “CO” will be displayed momentarily before reverting to the pH measurement mode.
6. For the greatest accuracy, perform a multiple-point calibration. Repeat step 1 with additional pH buffer calibration standard solutions.
3.1.2 Changing the pH Buffer Group
The meter can be calibrated with pH standards of USA, NIST (nSt) or Low Ionic (Pb) pH buffer groups. The factory default is the USA buffer group. To abort the buffer group selection, press CAL to revert to the pH measurement mode.
1. Press and hold MODE while switching the meter on using the ON/OFF key. The display will show “bUF” blinking.
2. Press the ENTER key to begin the buffer group selection mode. Use the MODE key to toggle between USA, NIST or Pb as shown below.
Press the ENTER key to confi rm the selection. The meter will automatically revert to the pH measurement mode. The meter will save the selected group indefi nitely until it is changed.
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3.1.3 Resetting User Calibrated Values
The calibrated pH values can be reset to the factory default using the procedure below. The temperature offset will not be reset using this procedure. To abort the reset, press CAL to revert to the measurement mode.
1. Press and hold CAL while switching the meter on using the ON/ OFF key. The DISPLAY will show “rSt” blinking.
2. Press the ENTER key to confi rm. The meter will automatically clear all stored pH calibrations and revert to the measurement mode.
3.2 Temperature Calibration
3.2.1 With Temperature Probe
The temperature probe supplied with the meter is factory calibrated. Over time, the temperature calibration may drift and require recalibration. If the temperature probe is replaced the meter should be recalibrated.
1. Connect the temperature probe to the meter. Press the MODE key until the “°C” annunciator appears on the DISPLAY.
2. Compare the displayed value to a NIST certifi ed thermometer or other thermometer known to be accurate. For the most accurate results, place both the probe and thermometer in a constant temperature bath.
3. Press the CAL key to enter the temperature calibration mode. The DISPLAY will show “CA” momentarily and the displayed reading will fl ash.
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4. Press INC key until the display shows the desired temperature. The meter will allow an adjustable maximum value of ±5 °C from the factory default.
5. To cancel or abort this operation, press the CAL key. To confi rm the calibration, press the ENTER key. A new value will be stored in the meter non-volatile memory. The meter will display “CO” momentarily, and then revert to the measurement mode.
3.2.2 Without Temperature Probe (no ATC)
If a temperature probe is not used, the meter will compensate the pH response based on a temperature value that has been manually set or at the factory default of 25.0 °C.
1. Press the MODE key until “°C” shows on the DISPLAY.
2. Compare the displayed value to a NIST certifi ed thermometer or thermometer that is known to be accurate (dipped into a constant temperature bath).
3. Press the CAL key to enter the temperature calibration mode. The DISPLAY will show “CA” momentarily and the displayed reading will fl ash. Note that the displayed value should be either
25.0 °C or the last set temperature value.
4. Press the INC key until the displays shows the desired temperature. The value can be set from 0 to 100 °C.
5. To cancel or abort this operation, press the CAL key. To confi rm the calibration, press the ENTER key. A new value will be stored in the meter non-volatile memory. The DISPLAY will display “CO” momentarily, and the meter will revert to the measurement mode.
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4. MEASUREMENT
4.1 Taking Measurements
1. Before measurement, rinse the pH probe and temperature probe with clean water to remove any impurities.
2. Power on the meter using the ON/OFF key. Press the MODE key to select the desired mode of operation (pH or Temperature).
3. Dip the probes in the aqueous test sample. Stir gently with the probes and wait for the reading to stabilize. Note the reading. Freeze the displayed if desired—for details refer to Section 4.2 Holding a Reading.
4. Rinse the probes with clean water before taking the next reading or storing the meter.
4.2 Holding a Reading
To freeze or hold the displayed reading, press the HOLD key once. The DISPLAY will display the ”HO” annunciator to indicate the HOLD function is activated.
4.3 Releasing a Held Reading
Press the HOLD key once again to deactivate the HOLD function or to release the frozen reading. The meter will revert to the current measurement mode, and the “HO” annunciator will disappear from the DISPLAY.
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5. ELECTRODE CARE AND MAINTENANCE
For best results, store the pH probe bulb wet. Store the pH glass bulb in pH probe storage solution. NEVER use deionized water for storage. Wash probes with clean water after each use.
pH probes are susceptible to contamination and dirt. Clean them as needed using mild detergent and warm water. Blot the probe gently with soft tissue paper to dry. Avoid excessive rubbing of the glass membrane and avoid touching it with the fi ngers. Recalibrate after cleaning.
6. TROUBLESHOOTING
Problem Cause Solution
No display Batteries not in place. a) Insert batteries.
b) Re-insert batteries in correct polarity.
“LO” displays in the LCD
Unstable reading
Not able to calibrate
Er1
Er3
Er5
Oe
uE
Low battery Replace batteries.
a) Electrode not deep enough in sample
b) Dirty electrode. c) Broken electrode
a) Display freezes b) Faulty electrode c) Inaccurate buffer
Buffer value out of tolerance Use new calibration solution and
ISE slope not within the specifi ed tolerance
Upon exit of calibration mode, a 1-point calibration was attempted with a pH buffer other than 7.00 or 6.86
Over range: reading exceeds maximum value
Under range: reading exceeds minimum value
a) Place electrode deeper in sample.
b)
Clean electrode and recalibrate.
c) Replace electrode.
a) Release reading by pressing HOLD.
b) Replace electrode. c)
Replace expired buffer solutions.
recalibrate. Ensure correct pH buffer group was selected.
Recalibrate
Repeat pH calibration using one or more points which include either 7.00 (USA) or 6.86 (NIST) standards.
Ensure that the value being measured is within the range of the selected mode. Confi rm that electrode(s) are connected and working properly.
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7. SPECIFICATIONS
pH Range 0.00 to 14.00 pH Resolution 0.01 pH Accuracy ±0.01 pH pH Slope Range 80 to 120% No. of Calibration Pts 1 to 3 points (push-button) Buffer Options pH 4.01, 7.00, 10.01 (USA)
pH 4.01, 6.86, 9.18 (NIST)
pH 4.10, 6.97 (Pb) Temperature Range 0.0 to 100.0 oC Resolution 0.1 °C Accuracy ±0.5 °C Temperature Comp. Automatic / Manual (0 to 100 °C)
Features
Auto-Buffer Recognition Yes Hold Function “HO” Auto Shut Off After 17 minutes Low Battery Indication “LO” Display Single Custom LCD Operating Temperature 0 to 50 °C Power Requirements 4 x “AAA” Alkaline Batteries Battery Life 500 hours Meter Dim./Weight 15.7 x 8.5 x 4.2 cm / 255 g
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8. REPLACEMENT PARTS AND ACCESSORIES
Item Description Code
pH Probe 1904 Temperature Probe 1909 AC Adapter, 110 mV 1726-110 AC Adapter, 220 mV 1754 Buffer, pH 4.01, 120 mL 2866-J Buffer, pH 7.00, 120 mL 2881-J Buffer, pH10.00, 120 mL 2896-J Mini Buffer Tablets, pH 4.0, 50 tablets 3983A-H Mini Buffer Tablets, pH 7.0, 50 tablets 3984A-H Mini Buffer Tablets, pH 10.0, 50 tablets 3985A-H
9. WARRANTY
LaMotte Company warrants this instrument to be free of defects in parts and workmanship for 3 years from the date of shipment and the probe to be free of defects in parts and workmanship for 6 months from the date of shipment. If it should become necessary to return the instrument for service during or beyond the warranty period, contact our Technical Service Department at 1-800-344-3100 or tech@lamotte.com for a return authorization number or visit www.lamotte.com for troubleshooting help. The sender is responsible for shipping charges, freight, insurance and proper packaging to prevent damage in transit. This warranty does not apply to defects resulting from action of the user such as misuse, improper wiring, operation outside of specifi cation, improper maintenance or repair, or unauthorized modifi cation. LaMotte Company specifi cally disclaims any implied warranties or merchantability or tness for a specifi c purpose and will not be liable for any direct, indirect, incidental or consequential damages. LaMotte Company’s total liability is limited to repair or replacement of the product. The warranty set forth above is inclusive and no other warranty, whether written or oral, is expressed or implied.
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10. RETURN OF ITEMS
Should it be necessary to return the meter for repair or servicing, pack the meter carefully in a suitable container with adequate packing material. A return authorization number must be obtained from LaMotte Company by calling 800-344-3100 (US only) or 410-778-3100, faxing 410-778-6394, or emailing tech@lamotte.com. Often a problem can be resolved over the phone or by email. If a return of the meter is necessary, attach a letter with the return authorization number, meter serial number, a brief description of problem and contact information including phone and FAX numbers to the shipping carton. This information will enable the service department to make the required
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PO Box 329 • Chestertown • MD • 21620
800-344-3100 • 410-778-3100 • f 410-778-6394
www.lamotte.com
626094-33 3.14
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