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Apera Instruments
Instruction Manual for APERA models including: PH700 Benchtop pH Meter, PH700, Benchtop pH Meter, pH Meter, Meter
1 - 1 Brief Introduction Thank you for purchasing Apera Instruments PH700 Benchtop pH meter. This instrument is an outstanding combination of advanced electronics design and sensor technology.
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DocumentDocumentPH700 Benchtop pH Meter Instruction Manual APERA INSTRUMENTS (Europe) GmbH www.aperainst.de Manual Version 3.2 Table of Contents 1 Brief Introduction ............................................................................................................- 1 1.1 Main Features ...................................................................................................................... - 1 - 2 Technical Specifications....................................................................................................- 1 - 3 What's in the Box?...........................................................................................................- 2 - 4 Instrument Description ....................................................................................................- 2 4.1 LCD Display .......................................................................................................................... - 2 4.2 Keypad ................................................................................................................................ - 3 4.3 Connectors .......................................................................................................................... - 4 4.4 Stable reading display mode................................................................................................. - 4 4.5 Data storage, recall, and deletion ......................................................................................... - 4 4.6 Max/Min Function ............................................................................................................... - 5 - 5 pH Measurement.............................................................................................................- 5 5.1 Preparation.......................................................................................................................... - 5 5.2 pH Electrode Information ..................................................................................................... - 5 5.3 Information regarding Calibration......................................................................................... - 6 5.4 pH Meter Calibration............................................................................................................ - 8 5.5 Measuring pH ...................................................................................................................... - 9 5.6 Parameter Setting .............................................................................................................. - 11 5.7 pH Electrode's Maintenance ............................................................................................... - 12 - 6 mV measurement .......................................................................................................... - 13 6.1 ORP measurement ............................................................................................................. - 13 6.2 Notes on ORP measurement............................................................................................... - 13 - 7 Recommended pH Electrodes for Specific Applications ................................................... - 14 - 8 Warranty ....................................................................................................................... - 14 - 1 Brief Introduction Thank you for purchasing Apera Instruments PH700 Benchtop pH meter. This instrument is an outstanding combination of advanced electronics design and sensor technology. It's the most economical choice of a reliable lab-grade benchtop pH meter. Please read this maual carefully to properly use and maintain the meter. Apera Instruments reserves the right to update the contents of this manual without giving prior notices. 1.1 Main Features · The meter has a built-in microprocessor chip, which enables intelligent functions such as automatic calibration, automatic temperature compensation, data storage, parameter setup, max/min reading display, etc. · The advanced automatic calibration mode has calibration guide and self-diganosis functions, automatically recognizing standard buffer solutions (USA or NIST series). · The advanced digital processing technology intelligently improves the meter's response time and measuring accuracy with stable reading display mode available. · The kit comes with a 3-in-1 combination pH Electrode, measuring pH and temperature simultaneously. · IP54 dustproof and spillproof. Connectors are protected by silicone seal caps, effectively ensuring the reliability and service life of the meter under harsh environment. · Detachable electrode holder and 3 bottles of pH buffer solutions come with the kit for convenient use. 2 Technical Specifications pH mV Temp. Others Range Resolution Accuracy Temperature Compensation Calibration Range Resolution Accuracy Range Resolution Accuracy Data Storage Storage Content Power IP Ratings Size and Dimension 0 to 14.00 pH 0.01/0.1 pH ±0.01 pH ±1 digit 0 to 100 °C (Auto or Manual) 1 to 3 points automatic calibration ±1999 mV 1 mV ±0.1% F.S ±1 digit 0 to 100°C; 32 to 212°F 0.1°C; 0.1/1°F ±0.5°C ±1 digit 50 groups Numberings, Measurement, Unit, Temperature, Temperature Compensation Status DC9V/300mA IP54 dustproof and spillproof (240*235*103) mm/1kg - 1 - 3 What's in the Box? Content 3.1 PH700 Benchtop pH Meter 3.2 201T-F Plastic 3-in-1 Combination pH Electrode 3.3 pH standard buffer solutions (4.00/7.00/10.01 pH) 3.4 9V Power Adapter 3.5 Electrode Holder 3.6 Instruction Manual 4 Instrument Description 4.1 LCD Display Quantity 1 1 1 for each 50ml 1 1 set 1 Figure-1 (1) -- Measurement value (2) -- Calibration icons and numberings (3) -- Measurement unit (4) -- Temperature and reminder icons (5) -- The pH unit displayed during calibration (6) -- The pH value displayed during calibration, numberings for storage and recall, and reminder icons (7) -- Icons for data storage and recall -- M+: store measuring data; RM: Recall measuring data (8) -- Self-Diagnosis icons and numberings (9) -- Temperature compensation mode icons: ATC: Auto Temperature Compensation; MTC: Manual Temperature Compensation (10) -- Completed calibration icons (11) -- Stable reading icon (12) -- Icons for maximum and minimum values - 2 - 4.2 Keypad 3.2.1. Keypad operations Figure-2 Short press ----- <1.5 seconds; Long press ----- >1.5 seconds. 3.2.2 For keypad operation, please see Table-1. Table 1 Keypad operations and descriptions Keypad Operation Functions Short Press · Power on/off Short Press · Select measuring mode: pHmV. Long Press · Enter parameter settingP1P2...P4. Short Press · · Enter Calibration mode Cancel any operation and go back to measurement mode Short Press · In calibration mode, press to conduct calibration · In parameter setting, press to confirm selection Short Press · Store measuring data Long Press · Recall stored measuring data · In manual temperature compensation mode, short press to change Short Press temperature, long press to change quickly or · In parameter setting mode, short press to change parameter and settings. Long Press · In recall mode, short press to change numberings, long press to change quickly. Short Press · Buttons for max/min values (refere to section 3.6) - 3 - 4.3 Connectors Symbol REF pH/mV TEMP DC9V Connector Name Socket for reference electrode Socket for pH and ORP electrode Socket for temperature sensor DC9V power socket Connector Type 2 banana type BNC RCA 2.5 direct type 4.4 Stable reading display mode When the measuring value is stable, smiley face icon appears on LCD, see Figure-3. Please do not get the reading value or make calibration until the icon appears and stays. 4.5 Data storage, recall, and deletion Storage When the measurement is stable, press key, the meter displays M+ icon and storage numberings on LCD, and stores the measuring data. In Figure-4, the meter stores the first group of the measuring data. Press again to keep storing. Figure - 3 Figure - 4 Recall stored data In the measurement mode, long press key to recall the last stored Measuring data. The meter displays RM icon and storage numberings. In Figure-5, the meter is recalling the 28th stored measuring data. Keep pressing and to recall the stored measuring data successively. Press and hold and to quickly recall the stored measuring data. Short press to go back to measurement mode. Figure - 5 - 4 - Clear stored data The meter can store 50 groups of data. Once the storage is full, if user presses again, the FUL icon will be displayed on LCD (see Figure-6). The storage needs to be cleared in parameter setting P4 so as to keep storing data. The numberings in M+ indicates the total number of stored data; The numberings in RM indicates the number of stored data in current mode (ph/mV). For example, if 20 groups of data is stored in pH mode, and 10 groups Figure - 6 in mV mode, then the numberings for M+ will be "M+30" in both pH and mV mode; the numberings for RM in pH mode would be "RM20", in mV mode "RM10". 4.6 Max/Min Function Use this function to display the maximum or minimum records out of groups of measuring data. In measurement mode, press , LCD will display flashing icons of "MAX/MIN", indicating the meter has entered the mode of recording maximum and minimum data. After testing, press again, LCD will alternately display the maximum and minimum value in the past measurements. Press to go back to regular measurement mode. 5 pH Measurement 5.1 Preparation Install the electrode holder The electrode holder is composed of a metal stand base, a supporting pole, and an electrode clip. First, install the metal stand base to the meter (screw it on). Please note that the metal base can be installed on either side of the meter. Then install the supporting bar on the metal stand base, and then install the electrode clip on the supporting bar. Connect the power adapter Plug the power adapter tightly into the DC9V socket. The power's voltage should meet the requirements listed on the power adapter. Things needed in addition to what's included in the box A clean cup, distilled water (8-16oz), and tissue papers for rinsing and drying the probe. 5.2 pH Electrode Information pH Electrode The meter comes with the 201T-F 3-in-1 combination electrode with a built-in temperature sensor, which enables the automatic temperature compensation. This electrode is only suitable for regular water solutions' pH testing. Please refer to Section 7 for ideal pH electrodes to use for other specific applications. The electrode's housing adopts polycarbonate materials, which is resistant to shocks and corrosion. A 3M KCL storage bottle comes with the electrode, which is for storing the electrode when not in use to keep the sensitivity of the probe. - 5 - Technical Specifications of the 201T-F pH Electrode Measurement Range: 0 - 14 pH, 0 - 80°C (32 176°F) Junction: Single Ceramic Reference Electrode: Ag/AgCl Connector: BNC/RCA Size: ø12*160 mm Temperature unit: 30K Thermistor Electrode Connectors The pH electrode has two connectors: the BNC connector connects the pH probe; the RCA connector connects the temperature sensor. Plug these two connectors into `pH/mV" and "TEMP" sockets. Please note not to pull the cables in case of poor contact. Please keep the connectors clean and dry. Refer to section 4.7 regarding how to properly maintain the pH electrode. Use the Electrode Screw off the KCL storage bottle, and put it aside (do not dump or spill the KCL solution). Prepare a cup of distilled water, and rinse the electrode in it for a few seconds. Gently shake the probe to remove excess water, and dry it with clean tissue paper (DO NOT rub or wipe the probe, just use paper to dap off excess water). Gently stir the electrode for a few seconds after it's dipped into the test solution and then let it stand still. Wait for the stable measurement (a smiley face appears and stays) and then record the readings. When test is finished, place the electrode in the storage bottle and tighten the cap in order to keep the sensitivity of the pH sensor. 5.3 Information regarding Calibration pH buffer solutions The meter has 2 series of standard buffer solutions: USA and NIST (see Table-2). They can be selected in parameter P1 (see 4.6.1). Calibration icon 3-Point calibration Table-2 pH standard buffer series USA NIST 1.68 and 4.00 pH 1.68 and 4.01 pH 7.00 pH 6.86 pH 10.01 pH 9.18 pH 3-Point Calibration The meter can adopt 1 to 3 points of calibration. The 1st point must be using 7.00 pH (or 6.86 pH) buffer solution, and then choose other buffers to do 2nd point and 3rd point. Please refer to Table-3 for details. In the process of calibration, the slope of acidity range and alkalinity range will be displayed, which indicates the health of your probe. The closer the slope is to 100%, the better the condition of the probe is. - 6 - USA Table-3 Calibration Mode NIS Calibration icon When to adopt 1-Point Calibration 7.00 pH 6.86 pH accuracy ±0.1 pH 7.00 pH and 6.86 pH and 2-Point 4.00/1.68 pH 4.01/1.68 pH Calibration 7.00 pH and 10.01 pH 6.86 pH and 9.18 pH Measuring range: 0 to 7.00 pH Measuring range: >7.00 pH 3-Point 7.00pH, 4.00/ 6.86pH, 4.01/ Calibration 1.68 pH and 10.01 pH 1.68pH, 9.18 pH Wide measuring range How often to calibrate The frequency that you need to calibrate your meter depends on the tested samples, condition of electrodes, and the requirement of the accuracy. For High-Accuracy meaustements ( ±0.02pH), the meter should be calibrated before test every time; For ordinary-accuracy measurements (±0.1pH), once calibrated, the meter can be used for about a week or longer. In the following cases, the meter must be re-calibrated: a) The electrode hasn't been used for a long time or a new electrode is connected. b) After measuring strong acid (pH<2) or strong base (pH>12) solutions. c) After measuring fluoride-containing solution and strong organic solution d) There is a significant difference between the temperature of the test sample and the temperature of the buffer solution that is used in the last calibration. - 7 - 5.4 pH Meter Calibration 1) Press to enter calibration mode. CAL1 icon will flash in the upper right corner of the LCD. 7.00 pH will flash in the lower right corner of the LCD, reminding you to use pH 7.00 buffer to conduct 1st point of calibration. 2) Use distilled water to rinse off electrode and then dry it (with a tissue). Dip it into pH 7.00 buffer solution, stir gently and let it stand still and wait for the reading to become stable. In the lower right corner of LCD, the process of auto recognizing the buffer solution will be displayed. Pressing before the buffer is recognized will generate Er2 (please refer to table 5). 3) When the meter locks 7.00 pH in the lower right corner, stable icon displays on LCD. Then press key to calibrate the meter. End icon appears after calibration is done. The 1st point calibration is finished. In the meanwhile, CAL2 will flash at the upper right corner, and 4.00 pH & 10.01 pH will flash alternately at the bottom right, indicating using pH4.00 or pH10.01 buffer solution to make the 2nd point calibration. 4) Take out the pH electrode, rinse it in distilled water, dry it, and dip it into pH 4.00 buffer solution. Stir the solution gently and let stand still in the buffer solution until a stable reading is reached. The meter's display will show the recognition process of calibration buffer solution at the lower right corner. When the meter recognizes 4.00 pH, stable icon displays on LCD. Press key to calibrate the meter. End icon and electrode slope of acidity range will be displayed after calibration is done. In the meanwhile, CL3 will flash at the upper right corner of the LCD, and 10.01 pH will flash at the lower right, indicating using pH10.01 buffer solution to make the 3rd point calibration. 5) Take out pH electrode, rinse it in distilled water, dry it, and dip it into pH 10.01 buffer solution. Stir the solution gently and let it stand still in the buffer solution until a stable reading is reached. The meter's display will show Figure-7 recognition process of calibration buffer solution at the bottom right of LCD. When the meter recognizes 10.01 pH, stable icon displays on LCD. Press key to calibrate the meter. End icon and electrode slope of alkalinity range display after calibration is done. The meter returns to the measurement mode, the calibration icons L M H will be displayed. Please see Figure-7 for the above calibration process. - 8 - 6) During the calibration process, press key to exit from the calibration mode. The meter can perform one-point, two-point and three-point calibration. Calibration guide icons appear on LCD. 5.5 Measuring pH Screw off the KCL storage bottle, and put it aside (do not dump or spill the KCL solution). Prepare a cup of distilled water, and rinse the electrode in it for a few seconds. Gently shake the probe to remove excess water, and dry it with clean tissue paper or Kimwipes (DO NOT rub or wipe the probe, just use paper to dap off excess water). Gently stir the electrode for a few seconds after it's dipped into the test solution and then let it stand still. Wait for the stable measurement (a smiley face icon appears and stays) and then record the readings. Please refer to Figure-8 for calibration and measurement process of the pH meter. Figure-8 Calibration and measurement process of pH meter Press to turn on the meter. Press key to enter the calibration mode. Submerge the electrode in pH7.00 solution, press key when icon appears. After the 1st point calibration is done, press key to enter the measurement mode. 1st point calibration Submerge the electrode in pH4.00 solution, press key when icon appears. After the 2nd point calibration is done, press key to enter the measurement mode. 2nd point calibration Sample Test Submerge the electrode in pH10.01 solution, press key when icon appears. After the 3rd point calibration is done, the meter enters the measurement mode automatically. 3rdpoint calibration Notes: 1) This default 201T-F electrode will NOT give accurate and stable pH readings when testing purified water such as distilled or deionized water. This because those water do not have enough ions present for the electrode to function properly. To measure distilled or deionized water's pH, users need to use a specialized pH electrode with the meter such as LabSenTM 803 Pure Water pH Electrode. Contact us at 1-614-285-3080 for more details. When testing purified water like spring water or drinking water, it will take longer for the readings to get stabilized (typically 3-5 minutes) because there is very few ions left to be detected by the sensor in those purified water. 2) Purified water such as distilled water and deionized water are recommended for only rinsing the probe for the best result. 3) The 201T-F pH Electrode is NOT suitable for testing high-temperature samples (>176°F). Testing high-temperature samples could cause permanent damage to the electrode. A specialized electrode such as LabSenTM 213 (up to 225°F) should be used in this situation. 4) The electrode housing is polycarbonate. When using cleaning solutions, take cautions on carbon tetrachloride, trichlorethylene, tetrahydrofuran, acetone, etc., which will dissolve the housing and invalidate the electrode. - 9 - 5.5.1 According to the pH isothermal measurement principle, the closer the test sample's temperature is to the calibration solution's, the higher the accuracy of the measurement. This principle is recommended to follow when conducting tests for the best result. Example: If users were to test samples at 150°F, we recommend warming up the calibration solutions to the same temperature before performing calibrations in order to get the most accurate readings. 5.5.2 The instrument has a function to return to factory default setting, which can be set up in P5 (refer to section 5.6). Returning to factory default setting is to restore the meter to theoretical value (zero potential pH is 7.00, slope is 100%), and set all the parameters to default settings. When the meter's calibration or measurement is performing abnormally, users can use this function to let the meter return to factory default mode, and then conduct calibration and test again. Please note that this function is irreversible once used. 5.5.3 Self-Diagnosis In the process of calibration and measurement, the meter has a self-diagnosis function. Please see table 5. Display Icons Table 5 Self-diagnosis Information Contents Wrong pH buffer solution or the buffer solution is out of range. pH electrode zero electric potential out of range (<-60mV or >60mV) pH electrode slope is out of range (<85% or >110%) Press key when reading is not stable during calibration. During calibration, the measuring value is not stable for 3min. How to fix 1. Check whether pH buffer solution is correct. 2. Check whether the meter connects the electrode properly. 3. Check whether the electrode is damaged. 4. Make sure there is no bubble in the electrode's bulb. 1. Make sure there is no bubble in the electrode's bulb. 2. Check whether the electrode is damaged. 3. Check if pH buffer solutions are correct. 4. The pH Electrode is aged. Replace a new one. Press key when icon appears and stays on the screen. 1. Make sure there is no bubble in the electrode's bulb. 2. Check whether the electrode is damaged. 3. The pH Electrode is aged. Replace a new one. * If you find any air bubble in the glass bulb of the pH sensor, simply shake the probe for a few times to remove it. The existence of an air bubble in the glass bulb will significantly decrease the stableness of measurement. - 10 - 5.6 Parameter Setting Symbol P1 P2 P3 P4 P5 Parameter setting content Select pH buffer series Select resolution Select temperature unit Clear stored data Return to factory default Table-6 Parameter USA - NIST 0.1/0.01 pH - No-Yes No-Yes Factory default setting USA 0.01 pH No No 5.6.1 How to do the parameter setting: In measurement mode, long press to enter parameter setting P1. Then press from P1 to P2...P5. For details, please see Table-7. Table-7 pH Parameter Setting to change menu P1 -- Select pH buffer series (USA-- NIS) 1. Long press to enter P1. 2. Press , USA flashes, press to select USA or NIS, press to confirm; USA -- USA SeriesNIS -- NIST Series 3. Press to enter P2 or press to return to measurement mode. P2 -- Select resolution (0.01--0.1) 1. Press , 0.01 flashes, press to confirm; 2. Press to enter P3 or press to select 0.01 or 0.1, press to return to measurement mode. P3 -- Select temperature unit (°C--°F) 1. Press , °C flashes, press to confirm; 2. Press to enter P4 or press to select °C or °F, press to return to measurement mode. P4 -- Clear stored data (No--Yes) 1. Press , "No" flashes, press to confirm; 2. Press to enter P5 or press to select No or Yes, press to return to measurement mode. P5 -- Restore to factory default setting (No--Yes) 1. Press , "No" flashes, press to select No to Yes, press to confirm; The meter returns to measurement mode. 2. If not selecting "Yes", press to return to measurement mode. - 11 - 5.7 pH Electrode's Maintenance 5.7.1 Daily maintenance The soaking solution contained in the supplied protective bottle is used to maintain activation in the glass bulb and junction. Loosen the cap, take out the electrode and rinse in distilled or water before taking a measurement. Insert the electrode and tighten the cap after measurements to prevent the solution from leaking. If the soaking solution is cloudy or moldy, replace the 3M KCL solution. * We DO NOT recommend using other brand's soaking solution, since different chemicals can be used and potential damage can be caused to the electrode) * The electrode should NOT be soaked and stored in purified or distilled water, protein solution, acid fluoride solution, or organic lipids. Distilled water or purified water is only recommended for rinsing electrodes. 5.7.2 Calibration buffer solution For calibration accuracy, the pH of the standard buffer solution must be reliable. The buffer solution should be refreshed often, especially after heavy use. We recommend 10-15 times of use before replacing the pH buffers. 5.7.3 Protect glass bulb The sensitive glass bulb at the front of the combination electrode should not come in contact with hard surfaces. Scratches or cracks on the electrode will cause inaccurate readings. Before and after each measurement, the electrode should be rinsed with distilled water or purified water. If a sample sticks to the electrode or it's contaminated, the electrode should be thoroughly cleaned using a soft brush with soap water and then rinsed with distilled water. After that, soak it in the KCL solution again for at least 6 hours. 5.7.4 Renew glass bulb Electrodes that have been used over a long period of time will become aged. Submerge the electrode in 0.1mol/L hydrochloric acid 24 hours, then rinse the electrode in distilled water, then submerge it in KCL soaking solution for 24 hours. The method to prepare 0.1mol/L hydrochloric acid: dilute 9mL hydrochloric acid in distilled water to 1000mL. For serious passivation, submerge the bulb in 4% HF (hydrofluoric acid) for 3-5 seconds, and wash it in distilled water, then submerge it in the soaking solution for 24 hours to renew it. 5.7.5 Clean contaminated glass bulb and junction (please refer to Table-8) Table-8 Clean contaminated glass bulb and junction Contamination Cleaning Solutions Inorganic metal oxide Dilute acid less than 1mol/L Organic lipid Dilute detergent (weak alkaline) Resin macromolecule Dilute alcohol, acetone, ether Proteinic haematocyte sediment Acidic enzymatic solution (saccharated yeast tablets) Paints Dilute bleacher, peroxide - 12 - 6 mV measurement 6.1 ORP measurement Press key, and switch the meter to mV measurement mode. Connect ORP electrode (the 301Pt-C combination ORP electrode is sold separately) and dip it in sample solution, stir the solution briefly and allow it to stay in the solution until icon appears and get the reading. ORP means Oxidation Reduction Potential. The unit is mV. 6.2 Notes on ORP measurement 6.2.1 ORP measurement does not require calibration. When the user is not sure about ORP electrode quality or measuring value, use ORP standard solution to test mV value and see whether ORP electrode or meter works properly. Table-9 is the data of standard ORP solution for 222 mV. Table-9 °C 10 15 20 25 30 35 38 40 mV 242 235 227 222 215 209 205 201 6.2.2 Clean and activate ORP electrode After the electrode has been used over a long period of time, the platinum surface will get polluted which causes inaccurate measurement and slow response. Please refer to the following methods to clean and activate ORP electrode: (a) For inorganic pollutant, submerge the electrode in 0.1mol/L dilute hydrochloric acid for 30 minutes, then wash it in distilled water, then submerge it in the soaking solution for 6 hours. (b) For organic or lipid pollutant, clean the platinum surface with detergent, then wash it in distilled water, then submerge it in the soaking solution for 6 hours. (c) For heavily polluted platinum surface on which there is oxidation film, polish the platinum surface with toothpaste, then wash it in distilled water, then submerge it in the soaking solution for 6 hours. - 13 - 7 Recommended pH Electrodes for Specific Applications Application Regular water solutions Beverage, beer, or wine analysis Cosmetics Dairy products (milk, cream, yogurt, mayo, etc.) High-Temperature liquid Low-temperature liquid Meat Micro sample testing Purified Water (Low ion concentration samples) Soil Solid or semi-solid samples (cheese, rice, fruit, etc.) Strong acid samples Strong alkalined samples Surface test (skin, paper, carpet, etc.) Titration TRIS buffer solutions Viscous liquid samples Wastewater or emulsion Ideal Apera pH Electrodes to Use with PH700 Meter 201T-F, LabSen 213 LabSen 213 LabSen 851-1, (MP500 temp. probe required) LabSen 823 LabSen 213 LabSen881 (MP500 temp. probe required) LabSen 763 LabSen 241-6, LabSen 241-3 (MP500 temp. probe required) LabSen 803, LabSen 813 LabSen 553 LabSen 753 LabSen 831 (MP500 temp. probe required) LabSen 841 (MP500 temp. probe required) LabSen 371 (MP500 temp. probe required) LabSen 223 LabSen 213, LabSen 223 LabSen 223, LabSen851-1 LabSen 333 8 Warranty We warrant this instrument to be free from defects in material and workmanship and agree to repair or replace free of charge, at option of APERA INSTRUMENTS(Europe) GmbH, any malfunctioned or damaged product attributable to responsibility of APERA INSTRUMENTS(Europe) GmbH for a period of TWO YEARS (SIX MONTHS for the probe) from the delivery. This limited warranty does not cover any damages due to: Transportation, storage, improper use, failure to follow the product instructions or to perform any preventive maintenance, modifications, combination or use with any products, materials, processes, systems or other matter not provided or authorized in writing by us, unauthorized repair, normal wear and tear, or external causes such as accidents, abuse, or other actions or events beyond our reasonable control. APERA INSTRUMENTS (Europe) GmbH Wilhelm-Muthmann-Straße 18, 42329 Wuppertal Germany Email: info@aperainst.de |ww.aperainst.de | Tel. +49 202 51988998 - 14 -