background image

Multi 3430

Overview

10

ba75865e19

04/2015

Function display

indicators

AutoCal 
e.g. TEC

Calibration with automatic buffer recognition, e.g. 
with the buffer set: Technical buffers

ConCal

Calibration with any buffers

Error

An error occurred during calibration

AR

Stability control (AutoRead) is active

HOLD

Measured value is frozen (

<AR>

 key)

Batteries are almost empty

Mains operation

Mains operation with charge function
Batteries are automatically charged in the back-
ground.

Data are automatically output to the USB-B inter-
face at intervals

Data are output to the USB-A interface (USB flash 
drive)

Data are output to the USB-A interface (USB 
printer)
If there is a USB-B connection (such as to a PC) at 
the same time, the data are output only to the 
USB-B interface.

Power supply via the USB-B interface
Batteries are not being charged

Summary of Contents for WTW Multi 3430

Page 1: ...OPERATING MANUAL ba75865e19 04 2015 Multi 3430 DIGITAL METER FOR DIGITAL IDS SENSORS...

Page 2: ...015 WTW GmbH Reproduction in whole or even in part is prohibited without the express written permission of WTW GmbH Weilheim Printed in Germany The latest version of the present operating manual is av...

Page 3: ...0 3 3 2 Connecting the power pack charging the batteries 20 3 3 3 Switching on the meter 21 3 3 4 Setting the date and time 22 4 Operation 23 4 1 Switching on the meter 23 4 2 Login with a user name 2...

Page 4: ...General information 64 4 9 2 Measuring 65 4 9 3 Settings for D O sensors menu or measurement and calibration settings 67 4 9 4 FDO Check procedure check of the FDO 925 70 4 9 5 D O calibration 72 4 9...

Page 5: ...USB A USB printer interface 109 4 14 5 Data transmission to the USB A interface USB memory device 110 4 14 6 MultiLab Importer 111 4 15 MultiLab User 111 4 16 Reset 111 4 16 1 Resetting the measuremen...

Page 6: ...Multi 3430 6 ba75865y19 04 2015 9 2 Firmware Update for IDS Sensors 132...

Page 7: ...bidity measure ments quickly and reliably The Multi 3430 provides the maximum degree of operating comfort reliability and measuring certainty for all applications The Multi 3430 supports you in your w...

Page 8: ...e under 2 sec in this operating manual A long keystroke approx 2 sec is indicated by the underscore behind the key symbol e g MENU ENTER_ 1 2 3 F1 F2 Softkeys providing situation dependent functions e...

Page 9: ...tings Confirms entries Opens the menu for system settings PRT PRT_ Outputs stored data to the interface Outputs displayed data to the interface in intervals ESC Cancels an action MENU ENTER MENU ENTER...

Page 10: ...lue is frozen AR key Batteries are almost empty Mains operation Mains operation with charge function Batteries are automatically charged in the back ground Data are automatically output to the USB B i...

Page 11: ...annot return any voltages or currents that are not allowed SELV and current circuit with current limiting WTW IDS sensors and IDS adapters meet these requirements Connectors 1 Digital sensors pH ORP c...

Page 12: ...o not concern this sensor To be able to use the automatic sensor recognition a meter that sup ports the automatic sensor recognition e g Multi 3430 and a digital IDS sensor are required In digital IDS...

Page 13: ...cedure A message is displayed while the data are being updated in the sensor 1 6 IDS adapter for analog sensors With the aid of an IDS adapter you can also operate analog sensors on the Multi 3430 An...

Page 14: ...Multi 3430 Overview 14 ba75865e19 04 2015...

Page 15: ...perience the operators will know the necessary safety precautions to take when handling chemicals Safety instructions Safety instructions in this operating manual are indicated by the warn ing symbol...

Page 16: ...left the factory in a safe and secure technical condition Function and operational safety The smooth functioning and operational safety of the meter can only be guaranteed if the generally applicable...

Page 17: ...you are in any doubt please contact the supplier of the meter Obligations of the purchaser The purchaser of this meter must ensure that the following laws and guidelines are observed when using danger...

Page 18: ...Multi 3430 Safety 18 ba75865e19 04 2015...

Page 19: ...in the following ways Battery operation with NiMh rechargeable batteries Mains operation with the supplied power pack The NiMh rechargeable batteries are automatically charged while the power pack is...

Page 20: ...ltage at the operating site must lie within the input volt age range of the original power pack see section 7 1 CAUTION Use original power packs only see section 7 1 CAUTION The batteries in the batte...

Page 21: ...ing feature to avoid unnecessary power consumption during battery operation The energy saving feature switches off the meter during battery opera tion if no key is pressed during the adjusted interval...

Page 22: ...Multi 3430 Commissioning 22 ba75865e19 04 2015 cable 3 3 4 Setting the date and time 3 See section 4 3 5...

Page 23: ...on is activated by the administrator via the MultiLab User PC software see the MultiLab User operating manual Switching off Press the On Off or On Off_ key 4 2 Login with a user name After activation...

Page 24: ...sing enter the User name menu item and confirm with MENU ENTER The user name is highlighted 3 Using select a user name and confirm with MENU ENTER 4 If a password is required Using enter the Password...

Page 25: ...er name menu item and confirm with MENU ENTER The user name is highlighted 3 Using select a user name and confirm with MENU ENTER 4 Using enter the Change password menu item and confirm with MENU ENTE...

Page 26: ...ion 4 3 1 and section 4 3 3 4 3 1 Operating modes The meter has the following operating modes Measuring The measurement data of the connected sensors is shown in the measured value display Calibration...

Page 27: ...operating situation 4 3 3 Navigation Measured value display In the measured value display you can use to select one of several connected sensors The selected sensor is displayed with a colored backgr...

Page 28: ...colon The current setting is displayed on the right hand side The setting mode is opened with MENU ENTER Subsequently the setting can be changed with and MENU ENTER Example Functions Functions are de...

Page 29: ...ng the language section 4 3 4 Setting the date and time see section 4 3 5 Calibration record Calibration data storage Buffer TEC Single point calibration yes Calibration interval 7 d Unit for slope mV...

Page 30: ...isplay appears The instrument is in the measuring mode 2 Open the Storage config menu with MENU ENTER_ The instrument is in the setting mode 3 Select the System submenu with The current selection is d...

Page 31: ...t the required language with General Interface Clock function Service information Reset System 15 03 2014 08 00 Language Deutsch Acoustic signal off Volume 5 Illumination on Brightness 50 Switchoff ti...

Page 32: ...es Therefore check the time at regular intervals Note After a fall of the supply voltage empty batteries the date and time are reset Setting the date time and date format The date format can be switch...

Page 33: ...ate function Reset of all sensor independent system settings to the default con dition 3 Select and confirm the Time menu with and MENU ENTER The hours are highlighted 4 Change and confirm the setting...

Page 34: ...ion on off System General Brightness 0 15 22 Changes the display bright ness System General Switchoff time 10 min 1h 24 h Adjusts the switch off time System General Temperature unit C F Temperature un...

Page 35: ...shes on the display as soon as the measured value is outside the stability range when you switch over between the measured parameters with M System Interface Extended Oxi output The measured values fo...

Page 36: ...storage function is active or with automatic data transmission 4 4 5 Display illumination The meter automatically switches the display illumination to energy saving mode if no key is pressed for 20 se...

Page 37: ...th More 15 03 2014 08 00 More SenTix 940 B092500013 15 03 2014 08 00 Man temperature 25 C pH resolution 0 001 mV resolution 0 1 Buffer TEC Calibration interval 7d Unit for slope mV pH QSC SenTix 940 B...

Page 38: ...ration and measurement settings siehe section 4 7 3 Preparatory activities Perform the following preparatory activities when you want to measure When operating a sensor without integrated temperature...

Page 39: ...ction is pre maturely terminated the current measurement data are output to the 1 Perform the preparatory activities according to section 4 7 1 2 Immerse the IDS pH sensor in the test sample 3 Select...

Page 40: ...ngs The settings are made in the menu for calibration and measurement settings of the pH ORP measurement To open the settings display the required parameter in the measured value display and press the...

Page 41: ...calibrate regularly by the flashing sensor symbol in the measur ing window Calibration Unit for slope mV pH Unit of the slope The display refers to the Nernst slope of 59 2 mV pH 100 x determined slop...

Page 42: ...a tion The pH values are valid for the specified temperature values The temperature dependence of the pH values is taken into consideration during the calibration Alternative temperature on off Takes...

Page 43: ...454 25 C 3 TEC WTW Technical buffers 2 000 4 010 7 000 10 011 25 C 4 Merck 1 4 000 7 000 9 000 20 C 5 Merck 2 1 000 6 000 8 000 13 000 20 C 6 Merck 3 4 660 6 880 9 220 20 C 7 Merck 4 2 000 4 000 7 000...

Page 44: ...C 15 Baker 4 006 6 991 10 008 25 C 16 Metrohm 3 996 7 003 8 999 25 C 17 Beckman 4 005 7 005 10 013 25 C 18 Hamilton Duracal 4 005 7 002 10 013 25 C 19 Precisa 3 996 7 003 8 999 25 C 20 Reagecon TEC 2...

Page 45: ...4 7 3 Stability control The calibration procedure automatically activates the stability control function The current measurement with stability control can be termi nated at any time accepting the cur...

Page 46: ...tion The zero point and slope are evaluated separately The worse evaluation of both is taken into account The evaluation appears on the display and in the calibration record Multi 3430 Ser no 09250023...

Page 47: ...QSC color scale flashes It is still possible to measure Note To ensure the high measuring accuracy of the measuring system cal ibrate after the calibration interval has expired Setting the calibratio...

Page 48: ...ion procedure is automatically finished with the measurement of buffer solution 1 and the calibration record is displayed 1 In the measured value display select the measured parameter pH or mV with M...

Page 49: ...ext buffer appears voltage dis play 8 If necessary finish the calibration procedure as a single point cal ibration with M The calibration record is displayed 15 03 2014 08 00 9 Thoroughly rinse the ID...

Page 50: ...ish the calibration procedure as a two point cal ibration with M The calibration record is displayed 15 03 2014 08 00 15 Thoroughly rinse the IDS pH sensor with deionized water 16 Immerse the IDS pH s...

Page 51: ...is determined by linear regression 19 Wait for the measurement with stability control to be completed or terminate the stability control and take over the calibration value with MENU ENTER The calibr...

Page 52: ...record is displayed 1 In the measured value display select the measured parameter pH or mV with M 2 Start the calibration with CAL The calibration display for the first buffer appears voltage dis pla...

Page 53: ...e the stability control and take over the calibration value with MENU ENTER The pH value of the buffer solution is displayed 8 Set the nominal buffer value for the measured temperature with 9 Accept t...

Page 54: ...rol The AR status indicator is displayed The measured parame ter flashes 15 Wait for the measurement with stability control to be completed or terminate the stability control and take over the calibra...

Page 55: ...the measurement with MENU ENTER The measured value is checked for stability stability control The AR status indicator is displayed The measured parame ter flashes 23 Wait for the measurement with stab...

Page 56: ...the MENU ENTER key in the measured value display Menu item Setting function Description Calibration Calibration data stor age Display Displays the calibration records Further options Scroll through t...

Page 57: ...lid calibration is available back ground color Measured values in this range are suitable for documentation 2 Measuring range for which no valid calibration is available light gray Measured values in...

Page 58: ...what is necessary to restore the optimum measuring quality e g clean calibrate or replace the sensor Sensor evaluation with without QSC function 15 03 2014 08 00 Info QSC color scale The double arrow...

Page 59: ...te As soon as the QSC function was enabled for an IDS sensor it is not possible to return to the sensor evaluation with the sensor symbol for this sensor Carrying out a QSC initial calibration Note Ca...

Page 60: ...ably changed after some normal calibrations Carrying out a QSC control calibration 4 As soon as the three point calibration has been successfully carried out you can decide whether to accept or discar...

Page 61: ...with several sensors connected to one Multi 3430 in one test sample Preparatory activities Perform the following preparatory activities when you want to measure 4 8 2 Measuring the ORP Note IDS ORP s...

Page 62: ...d time interval The minimum duration until a measured value is assessed as stable is the monitored time interval The actual duration is mostly longer 3 Select the mV display with M 1 Freeze the measur...

Page 63: ...measuring settings of the ORP measurement To open the settings display the required parameter in the measured value display and press the MENU ENTER key After completing the settings switch to the mea...

Page 64: ...ing cases Measurement in grounded test samples Measurement in one test sample with several sensors connected to one Multi 3430 Temperature measurement IDS D O sensors measure the temperature with a te...

Page 65: ...s displayed in the measuring win dow of the D O sensor In the measuring window of the IDS conduc tivity sensor providing the measured salinity value the Sal status indicator is displayed Manual determ...

Page 66: ...measurement data are not output to the interface 2 Release the frozen measured value again with AR The HOLD function is switched off The HOLD status display disappears 1 Freeze the measured value wit...

Page 67: ...correction Salinity salinity equivalent Settings The settings are available in the menu for measurement and calibration settings To open the settings display the required parameter in the measured va...

Page 68: ...days The FDO Check status display indica tor in the measuring window reminds you to check the sensor regularly Sal automatic on off Automatic salt content correction for concentration measurements Th...

Page 69: ...al filter is character ized by the response time t90 This is the time after which 90 of a signal change is displayed This menu item is only available if sensor and meter support this func tion Firmwar...

Page 70: ...ity assurance measures FDO Check procedure Check in water vapor saturated air Use the check and storage vessel to carry out the FDO Check proce dure Stability control AutoRead The Stability control fu...

Page 71: ...air saturated water the nominal value for the relative D O saturation abbreviated saturation is 100 Therefore the validity scope is 98 102 The check resulted in a measured value of 99 3 The measureme...

Page 72: ...ures Calibration in water vapor saturated air To calibrate the FDO 925 sensor use the check and storage vessel Stability control AutoRead In calibration the Stability control function AutoRead is auto...

Page 73: ...storage vessel long enough so it can adapt to the ambient temperature Display Calibration record Relative slope S 0 94 1 06 S 0 92 0 94 or S 1 06 1 08 S 0 90 0 92 or S 1 08 1 10 Error Error S 0 90 or...

Page 74: ...ty stability control The AR status indicator is displayed The measured parame ter flashes 5 Wait for the AutoRead measurement to be completed HOLD AR display or accept the calibration value with MENU...

Page 75: ...e MENU ENTER_ key in the measured value display Menu item Setting function Description Calibration Calibration data stor age Display Displays the calibration records Further options Scroll through the...

Page 76: ...nsors connected to one Multi 3430 Temperature measurement IDS sensors measure the temperature with a temperature sensor inte grated in the IDS sensor Preparatory activities Perform the following prepa...

Page 77: ...you switch the HOLD function off Note If the HOLD function is active you can e g start a manual measure ment with stability control Stability control AutoRead The stability control function AutoRead...

Page 78: ...the Stability control function manually The AR status indicator appears while the measured value is assessed as not stable A progress bar is displayed and the display of the measured parameter flashes...

Page 79: ...mperature compensation off Note The reference temperature and temperature compensation are set in the menu for the parameter conductivity see section 4 10 4 Application tips Select the following tempe...

Page 80: ...ith M The possible settings are individually displayed for each sensor Below the setting menu is displayed for two IDS sensors TetraCon 925 LR 925 01 Default settings are printed in bold Setting menu...

Page 81: ...set here Temp comp TC Method nLF Lin off Procedure for temperature com pensation see section 4 10 3 This setting is only available for the measured parameters and Temp comp TC Linear coeff 0 000 2 00...

Page 82: ...This setting is only available for the measured parame ters and Temp comp TC Linear coeff 0 000 2 000 10 000 K Coefficient of the linear tem perature compensation This setting is only available when t...

Page 83: ...KCl In the delivery condition the calibrated cell constant of the IDS sensor is set to 0 475 cm 1 conductivity measuring cell TetraCon 925 Stability control AutoRead In calibration the Stability cont...

Page 84: ...uctivity parame ter with M 3 Start the calibration with CAL The cell constant that was calibrated last is displayed 4 Immerse the IDS conductivity sensor in the control standard solution 0 01 mol l KC...

Page 85: ...ss the MENU ENTER key in the measured value display Menu item Setting function Description Calibration Calibration data storage Display Displays the calibration records Further options Scroll through...

Page 86: ...ies Avoid gas bubbles e g air bubbles in the test sample Use suitable vessels for measurement and calibration see operating manual of the VisoTurb 900 P sensor Heed the minimum depth of immersion for...

Page 87: ...If the HOLD function is active you can e g start a manual measure ment with stability control Stability control AutoRead The stability control function AutoRead continually checks the stability of the...

Page 88: ...longer 4 11 3 Settings for turbidity sensors 1 Freeze the measured value with AR The HOLD status indicator is displayed 2 Using MENU ENTER activate the Stability control function manually The AR stat...

Page 89: ...gular intervals Menu item Possible setting Explanation Calibration Calibration record Displays the calibration record of the last calibration Calibration Calibration data storage Display Displays the...

Page 90: ...ndard solution Range FNU NTU 1 0 0 1 0 2 5 0 200 0 3 200 0 4000 0 As the standard with turbidity value 0 0 FNU you can use clean tap water or filtered deionized water in a suitable cal ibration vessel...

Page 91: ...at an angle 8 Position the turbidity sensor in the measuring vessel see sec tion 4 11 1 9 Use and to set the concentration of the standard solution for each digit and confirm with MENU ENTER The stand...

Page 92: ...Calibration data storage Display To open the Cal ibration menu press the MENU ENTER key in the measured value display 12 Immerse the turbidity sensor in the test sample at an angle 13 Position the tur...

Page 93: ...er options Scroll through the cali bration records with Output the displayed cal ibration record to the interface with PRT Output all calibration records to the interface with PRT_ Quit the display wi...

Page 94: ...of all main measured values Example Depth of immersion as main and secondary measured value MPP 9x0 IDS with a pH IDS sensor of the XXX P series When the probe is equipped to capacity MPP 930 with 3 I...

Page 95: ...uipment of the MPP 9x0 IDS the following value is displayed as the depth of immersion the depth of immersion of the connected IDS sensors averaged value for all IDS sensors of the XXX P series the dep...

Page 96: ...04 2015 1 Connect the IDS sensors of the XXX P series or Close any open plug in positions on the MPP 9x0 IDS with blind plugs 2 Connect the MPP 9x0 IDS multi parameter probe to the meter The depth of...

Page 97: ...DPT Then you can enter the salinity salt content of the test sample see section 4 12 3 If the salinity correction is switched on the Sal display appears in the measurement window of the parameter dep...

Page 98: ...e Stability control function monitors whether the measured values are stable during the monitored time interval 2 Release the frozen measured value again with AR The HOLD function is switched off The...

Page 99: ...use M to switch to the measured value display The possible settings are displayed individually for each sensor Default settings displayed in bold Setting menu Measured parameter Time interval Stabilit...

Page 100: ...be is still open Connect a sensor or Close the plug in position with a blind plug A blind plug is not recognized Check the blind plug Unplug all sensors from the meter Connect the blind plug to the me...

Page 101: ...an IDS sensor of the XXX P series directly to the meter with a cable 4 Carry out the function Calibrate the IDS sensor see section for measured param eter Reset the IDS sensor see section for measured...

Page 102: ...ID number Measured value of the connected sensor Measured temperature value of the connected sensor AutoRead info AR appears with the measured value if the AutoRead criterion was met while storing sta...

Page 103: ...13 2 Automatic storage at intervals The storage interval Interval determines the time interval between automatic storage processes Each storage process transmits the cur rent dataset to the interface...

Page 104: ...Max available storing duration Graphical display of the storage usage Menu item Possible setting Description ID number 1 10000 ID number for the dataset series Interval 1 s 5 s 10 s 30 s 1 min 5 min...

Page 105: ...h off function are deactivated Terminating the automatic storage function prematurely Proceed as follows to switch off the automatic storage function before the adjusted storage duration has expired 1...

Page 106: ...as an exam ple The same settings and functions are available for the automatic storage Settings Menu item Setting function Description Data storage Manual data storage Display Displays all measurement...

Page 107: ...rage How to erase the measurement data memory is described in section 4 13 3 EDITING THE MEASUREMENT DATA STORAGE Manual data storage 3 of 64 15 03 2014 11 24 16 ID number 1 SenTix 940 B20234008565 pH...

Page 108: ...a the USB B interface Installation of the USB driver on the PC System requirements of the PC for installation of the USB driver PC with at least one free USB connection and CD ROM drive Windows 2000 W...

Page 109: ...transmit data to a USB memory device is described in an extra section see section 4 14 5 The following table shows which data are transmitted to the interface in which way 1 Connect a USB memory devic...

Page 110: ...5 The following table shows which data are transmitted to the interface in which way Current measured values of all connected sensors Manual With PRT Simultaneously with every manual storage process s...

Page 111: ...initialize all sensor settings and sensor independent settings separately from each other 4 16 1 Resetting the measurement settings Note The calibration data are reset to the default settings togethe...

Page 112: ...t settings To open the settings display the required parameter in the measured value display and press the MENU ENTER key Dissolved oxygen The following settings for D O measurements are reset to the...

Page 113: ...n The sensor settings are reset under the Reset menu item in the menu for calibration and measurement settings To open the settings display the required parameter in the measured value display and pre...

Page 114: ...are reset in the menu Storage config System Reset To open the Storage config menu press the MENU ENTER_ key in the measured value display Setting Default settings Language English Acoustic signal on V...

Page 115: ...the rechargeable batteries are posi tioned correctly The signs on the batteries must correspond to the signs in the battery compartment Note Dispose of used batteries according to the local regulatio...

Page 116: ...h Disinfect the housing with isopropanol as required CAUTION The housing is made of synthetic material ABS Thus avoid con tact with acetone or similar detergents that contain solvents Re move any spla...

Page 117: ...y Charge the batteries see section 3 3 2 CONNECTING THE POWER PACK CHARGING THE BATTERIES Replace the batteries see section 5 1 MAINTENANCE Cause Remedy Operating condition undefined or EMC load unall...

Page 118: ...ting erases all data on the USB memory device Back up all data before reformatting Cause Remedy The USB B interface is con nected to a PC Disconnect the PC from the USB B interface Connected USB memor...

Page 119: ...What to do if Multi 3430 119 ba75865e19 04 2015 Error message Memory error 1 Cause Remedy Instrument storage was not found Please contact the service...

Page 120: ...lyte dried out Exchange IDS pH sensor Cause Remedy IDS pH sensor The values determined for zero point and slope of the IDS pH sensor are outside the allowed limits Recalibrate Junction contaminated Cl...

Page 121: ...le Adjust temperature if neces sary IDS pH sensor test sample Conductivity too low Use suitable IDS pH sensor Temperature too high Use suitable IDS pH sensor Organic liquids Use suitable IDS pH sensor...

Page 122: ...ng medium Defective sensor Replace sensor Note More information as well as notes on cleaning and replacement of sensors are given in the documentation of your sensor Cause Remedy Measured value outsid...

Page 123: ...ection light Check the calibration Minimum depth of immersion not observed Heed the minimum depth of immersion of the sensor 2 cm Cause Remedy Measured value outside the measuring range Select a suita...

Page 124: ...Multi 3430 What to do if 124 ba75865e19 04 2015...

Page 125: ...her days 85 Power supply Rechargeable batteries 4 x 1 2 V NiMH rechargeable batteries type AA Operational life Approx 150 h Power pack charging device Kuantech Co Ltd KSAC 0900110W1UV 1 Input 100 240...

Page 126: ...This equipment has been tested and found to comply with the limits for a Class A digital device pursuant to Part 15 of the FCC Rules These limits are designed to provide reasonable protection against...

Page 127: ...the oxygen in a gas mixture or liquid Electromotive force of an electrode The electromotive force U of the combination electrode is the measur able electromotive force of an electrode in a solution It...

Page 128: ...of dissolved salts to the mass of the solution in g kg In practice this dimension cannot be measured directly Therefore the practical salinity according to IOT is used for oceanographic monitoring It...

Page 129: ...88 90 D Dataset 82 Date and time 31 Default settings Measured parameter 91 System settings 94 Display 11 E Energy saving feature 23 F Firmware update 107 I Initial commissioning 21 23 Initialize 91 In...

Page 130: ...lity control automatic 35 Conductivity 73 O2 65 ORP 61 pH 38 Storage interval 83 Storing in memory 63 Automatic 83 Manual 83 T Temperature compensation 75 Temperature measurement Conductivity 71 O2 63...

Page 131: ...and on you can check whether the meter has taken over the new software version see page 117 1 Install the downloaded firmware update on a PC An update folder is created in the Windows start menu If a...

Page 132: ...irmware update on a PC An update folder is created in the Windows start menu If an update folder already exists for the sensor or sensor type the new data are displayed there 2 In the windows start me...

Page 133: ......

Page 134: ...water needs Developing new technologies that will improve the way water is used conserved and re used in the future is central to our work We move treat analyze and return water to the environment and...

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