Aanderaa 4330 Скачать руководство пользователя страница 19

Страница: 19 / 93

TD 269 OPERATING MANUAL

OXYGEN OPTODE 4330, 4831, 4835

June 2017

page 19 of 93

At normal atmospheric pressure (1013 mbar) the measured

concentration should not be pressure

compensated. As the sensor is submerged you must perform pressure compensation of 0.0032% per

dbar or for every meter increase of the relative pressure.

The relative pressure = absolute pressure (measured with the optode) – atmospheric pressure (normally

set to 1013 mbar).

Example 1: The measured O

concentration with an Optode is 400

M. The measurement was performed

at 1m depth, which is 1dbar relative pressure.

= 400×1.000032= 400.012

Example 2: The measured O

concentration with the Optode is 400

M. The measurement was

performed at 1000m depth, which is 1000dbar relative pressure.

=400×1.032= 412.8

Содержание 4330

Страница 1: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 1 of 93 OXYGEN OPTODE 4330 4835 4831 ...

Страница 2: ...roved accuracy and artificial oxygen consumption by sacrificial anode updated FAQ Rebranded 5 th Edition February 2014 Updated text on page 17 54 and 55 6 th Edition September 2015 Correction in formula page 56 7 th Edition June 2017 New foil Kit 5551 added NOTE The latest version of the FAQ for the Oxygen Optodes is available on our web site Copyright Aanderaa Data Instruments AS Contact informat...

Страница 3: ...libration Coefficients and Salinity Compensation 22 CHAPTER 4 Sensor configuration using Real Time Collector 25 CHAPTER 5 Connection to PC 27 5 1 RS232 Communication Setup 27 5 2 Passkey for Write Protection 28 5 3 Save and Reset 29 5 4 Communication Sleep 29 5 5 Available Commands for the Oxygen Optodes 30 5 5 1 The Get Command 31 5 5 2 The Set Command 31 5 5 3 Formatting the Output String 32 5 5...

Страница 4: ...ode 4835 51 Appendix 6 Primer Oxygen Calculations in the Sensor 52 Appendix 7 Multipoint Calibration 56 Appendix 8 Illustrations 57 Appendix 9 Frequently Asked Questions FAQ 66 Appendix 10 List of scientific papers 84 Appendix 11 Product Change Notification Framework 3 86 Appendix 12 Oxygen Dynamics in Water 89 Seawater and Gases 89 Tables 89 ...

Страница 5: ...r security and future expansion Both the Smart Sensor Terminal protocol and the AADI Real Time protocol was updated with this version of the Smart Sensor firmware see appendix 11 Aanderaa Smart Sensors utilize common communication protocols at the RS232 and RS422 interface where the Smart Sensor Terminal protocol is a simple ASCII command string based protocol and the AADI Real Time is an XML base...

Страница 6: ...tion protocol Chapter 6 describes maintenance procedure for changing foil and functional test for the sensors The Appendix includes the principle behind the Oxygen Optodes electronic and mechanical design calibration procedures including the Stern Volmer Uchida formula implemented with the new Optode framework 3 introduced in August 2012 The new firmware also allows an optional high accuracy multi...

Страница 7: ...tode 4330 4330F D 403 Data sheet Oxygen Optode 4831 4831F D 385 Data sheet Oxygen Optode 4835 Abbreviations O2 Oxygen molecule LED Light Emitting Diode ADC Analogue to Digital Converter DSP Digital Signal Processor EPROM Erasable Programmable Read Only Memory ASCII American Standard Code for Information Interchange MSB Most significant bit UART Universal Asynchronous Receiver Transmitter RTC Real ...

Страница 8: ...ide and Pressure Features common to these sensors include Internal Digital Signal Processor DSP to optimise data acquisition and improve accuracy resolution and stability Multi parameter outputs measured calculated presented within the sensor e g for oxygen O2 in µM O2 in saturation Temperature and Raw data Calibration coefficients stored in sensor and unique sensor identification number Autonomou...

Страница 9: ...0 4831 4835 June 2017 page 9 of 93 Figure 1 1 Illustration of the Oxygen Optode 4330 Figure 1 1A Oxygen Optode 4330 Pin Configuration Screws 4 for attaching the Securing Plate Temperature sensor Sensing Foil Sensor Housing Sensor foot O rings ...

Страница 10: ...4835 June 2017 page 10 of 93 Figure 1 2A Oxygen Optode 4831 Pin Configuration Screws 4 for attaching the Securing Plate Temperature sensor Sensing Foil Sensor Housing Wet mate Connector Subconn MCBH8M Figure 1 2 Illustration of the Oxygen Optode 4831 ...

Страница 11: ...in Configuration 1 1 Pin Configuration The Oxygen Optode 4330 4831 and 4835 pin configuration is given in Figure 1 1A 1 2A and 1 3A above A description of the receptacle notation is given in Table 1 1 Screw for attaching the Securing Plate Temperature sensor Sensing Foil Sensor Housing Sensor foot O rings Screw for attaching the Securing Plate Securing Plate ...

Страница 12: ...ceive line RS232 TXD RS232 Transmit line Analog 1 Analog output no 1 0 5V SGnd 1 Signal ground for Analog output no 1 Analog 2 Analog output no 2 0 5V SGnd 2 Signal ground for Analog output 2 1 2 User Accessible Sensor Properties All configuration settings that determines the behavior of the sensor are called properties and are stored in a persistent memory block flash One property can contain sev...

Страница 13: ...g 31 Last calibration date format YYYY MM DD Calibration Interval INT 1 Recommended Calibration Interval in Days Node Description String 31 User text for describing node placement etc UM High Interface ENUM 1 Sensor interface Select either RS232 or RS422 N A for Oxygen Optode Baudrate ENUM 1 RS232 baudrate 300 1200 2400 4800 9600 57600 115200 1 Flow Control ENUM 1 RS232 flow control None or Xon Xo...

Страница 14: ...nt calibration data air pressure hPa CalDataZero Float 2 Two point calibration data raw phase and temperature 0 air saturation Enable RedReference BOOL 1 Controls the use of the red reference LED RedReference Interval INT 1 Sample interval divisor for use of red reference Examples Value 1 for using red reference for each sample Value 10 for using red reference for each 10th sample Mode ENUM 1 Oper...

Страница 15: ... 9600 may limit the sampling frequency 2 Applicable to 4831 only 1 3 Specifications For product specifications refer Datasheet D378 for 4330 4330F D385 for 4835 and D403 for 4831 4831F on our web site http www aaderaa com or contact aanderaa info xyleminc com You will always find the latest versions of our documentation on the web Customers can register to obtain a username and password necessary ...

Страница 16: ...ls in the dark and to soak sensors in water at least 24 hours prior to calibration or deployment Sensor are delivered with a reusable black rubber protection cap and it is recommended to add a wet piece of natural sponge to keep the sensor foil wet at all times during storage For more details on these and other issue please see pages 46 47 along with FAQ s in appendix The sensing foil is fixed aga...

Страница 17: ...nominal air pressure 1013 25 hPa These values do not need to be salinity compensated The ambient Temperature is presented in ºC The optode raw data are the phase and amplitude of the returned signal after the luminophore quenching CalPhase deg Calibrated phase TCPhase deg Temperature compensated phase C1RPh deg Phase measurement with blue excitation light C2RPh deg Phase measurement with red excit...

Страница 18: ...6 90358e 3 B3 4 29155e 3 If the Salinity property in the optode is set to other than zero zero is the default value the equation becomes 2 2 2 0 2 0 3 3 2 2 1 0 0 S S C T B T B T B B S S C S S S e O O Where S0 is the internal salinity setting 2 4 Depth Compensation of Data The response of the sensing foil decreases to some extent with the ambient water pressure 3 2 lower response per 1000 m of wat...

Страница 19: ...er increase of the relative pressure The relative pressure absolute pressure measured with the optode atmospheric pressure normally set to 1013 mbar Example 1 The measured O2 concentration with an Optode is 400 µM The measurement was performed at 1m depth which is 1dbar relative pressure O2c 400 1 000032 400 012 µM Example 2 The measured O2 concentration with the Optode is 400 µM The measurement w...

Страница 20: ...n corrosion protected by sacrificial anodes As the anode disintegrates oxygen is consumed at all naked exposed metal parts with which the anode is in electrical contact The oxygen consumption can be significant e g during its lifetime normally 1 2 years a 130 g Zn anode mounted on a SEAGUARD RDCP RCM pressure case can consume all oxygen in about 700 l of water In areas where very low circulation c...

Страница 21: ...ion guide TN309 holds an extract of sensor connection disconnection given in the SEAGUARD Operating Manual Note Always replace O rings when removing exchanging or installing a new sensor or a sealing plug Apply Tectyl 506 included in Maintenance Kit in the slit between the Sensor and the Top end plate to prevent crevice corrosion of the Top end plate Figure 3 1 Illustration of the SEAGUARD Top end...

Страница 22: ...this will typically lead to 1 3 lower readings depending on the relative humidity of the air The absolute oxygen level µM is a default parameter and cannot be disabled refer TD262a To enable disable a parameter Select the output parameter from the list press View Edit in the lower part of the window and change the setting by clicking the box box is now checked press Save to save and close the wind...

Страница 23: ...ata The text is by default set to the product name followed by product and serial number e g Optode Sensor 4330 52 Press Next to continue with the next submenu The second submenu in the Oxygen Optode user maintenance holds a setting for the Salinity Select the Salinity property tap View Edit and type the salinity value Press Save to store the setting Note If you are post compensating for the salin...

Страница 24: ...nt situations contact AADI service department RedReference Interval this is a sample interval divisor for use of red reference When the value is set to 1 default the red reference measurement is performed during each sample The value can be increased to reduce power drain or to set a fast sampling interval less than 2 sec When the value is set to e g 10 the red reference measurement is only perfor...

Страница 25: ...n Device Configuration and press Get Current Configuration Check Include User Maintenance to view maintenance settings The password is 1000 Figure 4 1AADI Real Time Collector screen views User accessible sensor properties are found in Deployment settings System Configuration and User Maintenance Refer table Table 1 2 in chapter 1 2 for an overview of the properties Refer chapter 5 7 for a descript...

Страница 26: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 26 of 93 Figure 4 3 Sensor system configuration Figure 4 4 Sensor user maintenance ...

Страница 27: ...al power 5 14V refer Figure 5 1 Note If power cannot be obtained from an USB port a practical solution is to use a 9V alkaline battery 6LF22 to set the sensor up or log it in the laboratory Sensor Cable 4865 5335 are also available in other lengths The cable has a titanium plug and can be used in applications that require a direct connection to a PC in RS232 operations Figure 5 1 Sensor Cable 3855...

Страница 28: ...ain command MainCmd is followed by an optional subcommand SubCmd or sensor property Property The MainCmd and the SubCmd Property must be separated with the space character When entering new settings the Property is followed by parentheses containing comma separated values The command string must be terminated by Carriage Return and Line Feed ASCII code 13 and 10 The command string is not case sens...

Страница 29: ...ffect This can be done by recycling power or entering the Reset command At start up reset the sensor normally presents a start up information string as shown Figure 5 2 Figure 5 2 Sensor start up reset 5 4 Communication Sleep If the property Comm TimeOut is set to other than Always On the serial interface will not be activated after power up or the Reset command Any character will activate the ser...

Страница 30: ...pe only used when changing between standard foil and fast response foil Refer chapter 6 1 Get ConfigXML Outputs info on available properties on XML format Get DataXML Outputs info on available enabled parameters on XML format Get Property Output Property value refer Table 1 2 Get All Output all property values Set Property Value Value Set Property to Value Value Set Passkey Value Set passkey to ch...

Страница 31: ...operty refer example in Figure 5 3 The command name Get followed by a parameter returns the name and unit of the parameter the product and serial number of the sensor and finally the latest parameter reading refer example in Figure 5 3 Figure 5 3 Examples of the Get command A special version Get All reads out all available properties in the sensor 5 5 2 The Set Command The Set command is used for ...

Страница 32: ...DecimalFormat controls the format of the output values either as decimal numbers Yes or in exponential format No Refer Figure 5 5 for an example 5 5 4 XML Commands Get ConfigXML presents the configuration of all the sensor properties in XML format Get DataXML presents all of the enabled parameters in XML format 5 6 Scripting sending a string of commands Often it may be usefully to collect more tha...

Страница 33: ...erties and the input format below follows a description of the properties that are typically set by the user prior to a deployment RS232 application Description of properties regarding the sensing foil and calibration are given in CHAPTER 6 The Mode property is used to set the operation mode Available modes are AiCaP Smart Sensor Terminal AADI Real Time and Analog Output Set Mode to AiCaP when con...

Страница 34: ...e Salinity property according to the known value and the measurements will be salinity compensated inside the sensor before presentation useful for Real Time measurements The Enable HumidityComp property describes compensation of vapour pressure in the calculations of the output parameters Enable HumidityComp can be set to No if measurements are performed in complete dry conditions dry air or if y...

Страница 35: ...eaned using a brush and clean water Carefully use a wet cloth to clean the sensing foil Fouling consisting of calcareous organisms e g barnacles can be dissolved by dipping the sensor instrument in a weak acid solution e g 7 Vinegar If the sensing foil is scratched or if the protective black layer on the foil is removed the sensor will still work as long as there is enough Fluorophore on the foil ...

Страница 36: ...he fast response foil will normally require more frequent calibration but this is highly dependent on the amount of ambient light When saturated with moisture the polymer of the sensing foil will swell a little This will cause a minor approximately 2 change in the response of the Optode For optimum accuracy the foils should be wetted for 48 hours prior to use The protecting cap supplied with the 4...

Страница 37: ... is given below the table NOTE If you use a foil from a different batch new foil coefficients must be entered NOTE After changing the foil and entering new foil coefficients a new two or multipoint calibration should be performed see below Table 6 1 Contents of Sensor Foil Kit 4733 4794 5551 Part no Pieces Description Foil Kit 4733 Foil Kit 4794 Foil Kit 5551 1206005A 1 Standard Sensing Foil packe...

Страница 38: ...oil to fit the optical window It is important that the standard foil is mounted with the black side out and the fast response foil with the non glossy side out Remount the securing plate Figure 6 3 optical signal levels of the fast response foil are quit different from the standard foil If changing from a standard foil to a fast response foil our vice versa the internal amplification should be opt...

Страница 39: ... in the future it should be pre cleaned and rinsed then packed in a light blocking package marked with the foil type and batch number Center the new foil to fit the optical window It is important that the standard foil is mounted with the black side out Remount the securing plate Control and if necessary update the sensing foil coefficients according to the foil certificate refer chapters 3 2 4 1 ...

Страница 40: ...e sensor measurements are representative for the temperature of the foil The saturation will be significantly lower when you breathe on or near the sensing foil The measured temperature should also agree with the ambient temperature 6 2 1 SEAGUARD Applications Leave the Oxygen Optode 4330 4835 mounted onto the SEAGUARD Platform Power the instrument refer TD262a and TD262b for operating instruction...

Страница 41: ...ing updates according to the update interval Press Freeze to temporarily stop the update press Start to restart monitoring Start is the same button as Freeze Press Cancel to stop monitoring The sensor readings should be according to the description in chapter 6 2 Calibration AADI has discovered that an after curing occures in the foils during the first 1 3 months after the foil was manufactured wh...

Страница 42: ... glass of the same water as for air saturation and dissolving 5g of sodium sulphite Na2SO3 in 500ml water 6 2 2 Calibration Procedure using a Terminal Program NOTE To obtain the highest accuracy the sensor s to be calibrated should be submerged into water at least 24 48 hours prior to the calibration If a sensor is allowed to dry out this could lead to a bias in the readings of up to 2 This effect...

Страница 43: ... 2 03067907E 01 1 72740886E 03 Set FoilCoefB 1 23230336E 05 0 0 0 0 0 0 0 0 0 0 0 0 0 Set FoilPolyDegT 1 0 0 0 1 2 0 1 2 3 0 1 2 3 4 0 0 0 0 0 0 0 0 0 0 0 0 0 Set FoilPolyDegO 3 4 3 2 2 2 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Save Type Get All to verify the new coefficients Script files for entering the foil coefficients via text terminal programs will be available from the factory 1 Submerg...

Страница 44: ...y 1000 Do CollectCalDataZero 5 Enter the Do Calibrate command to effectuate the new calibration and store the new coefficients in the sensor memory The save command is automatically performed Set Passkey 1000 Do Calibrate Check that the sensor is working properly by taking it up into the air and rinse off flush the sensor well to remove all of the Zero Oxygen water to not have cross contamination ...

Страница 45: ...emit a photon of lower energy and return to its initial state Some types of luminophores might also return to the initial state when colliding with certain other molecules Figure A 1 Dynamic Luminescence Quenching O2 Absorbing Photon O2 not present L Luminophore in excited state L Luminophore in initial state L L L O2 O2 present L L L Energy transferred to Oxygen molecule Luminophore returned to i...

Страница 46: ...se time foils also exist without the optical isolation layer transparent foils through which the blinking blue and red light can be seen The transparent foils are only available for 4330 and 4831 optodes Figure A 2 Sensing Foil Luminescence Decay Time Due to its fluorescent behaviour the sensing foil will return a red light when it is excited with a blue green light 505 nm If there is O2 present t...

Страница 47: ...y In order to measure this luminescence decay time the sensing foil is excited with a blue green light modulated at 5 kHz The decay time is a function of the phase of the received signal In the Oxygen Optode the relationship between the phase and the O2 concentration is used directly without calculating the decay time Figure A 3 shows a typical relationship between the phase measurement and O2 con...

Страница 48: ... the foil The photodiode is used for sensing the fluorescent light Even thought the sensing foil is highly fluorescent parts of the transmitted light will be directly reflected The photo diode is equipped with a colour filter that stops light with short wavelengths to minimize the influence of the reflected light Further the blue green LED is equipped with a filter that stops light with long wavel...

Страница 49: ...0 100 0 350 400 450 500 550 60 650 700 Wavelength nm Relative Response Blue Green LED Blue Filter Red LED Red Filter Photo Diode 90 80 70 60 50 40 30 20 10 100 0 90 80 70 60 50 40 30 20 10 100 0 350 400 450 500 550 60 650 700 350 400 450 500 550 60 650 700 Wavelength nm Relative Response Blue Green LED Blue Filter Red LED Red Filter Photo Diode ...

Страница 50: ...n of Optode 4330 and 4831 Figure 1 1 and Figure 1 2 and Figure 1 3 and A8 for illustration of the Oxygen Optode 4330 A cylindrical titanium housing shields the electronics from the surrounding water and high pressure pressure resistance for standard sensor is 6000 m These sensors do also exist in a special 12 000 m rated version A 4mm thick sapphire window provides the optical connection between t...

Страница 51: ...w provides the optical connection between the optics inside the Optode and the sensing foil on the outside The foil is fixed to the window by a POM securing plate and is easily replaceable A 10 pin receptacle in the sensor foot provides all electrical connection to the sensor To prevent potential leakage from the sensor to the rest of the measurement system the receptacle is moulded inside a recep...

Страница 52: ...as t B Phase C Phase C t A TPhase 2 1 The A t and B t are 3 rd order temperature dependent polynomials that provides for a possibility for temperature compensation of the phase measurement Normally this option is not used and A t 0 B t 1 Coefficients for A and B are held in the properties called PTC0Coef and PTC1Coef respectively Subsequently the CalPhase is calculated as 3 3 2 2 1 0 TPhase PhaseC...

Страница 53: ...FoilPolyDegO From the partial pressure the air saturation is then calculated as NomAirMix t p ess NomAir p ion AirSaturat vapour Pr 100 where NomAirPress is a property for the nominal air pressure usually 1013 25 hPa and NomAirMix is the nominal O2 content in air by default 0 20946 The pvapour t is the vapour pressure calculated from temperature by the following equation t t vapour e t p 15 273 ln...

Страница 54: ...tionship between the phase shift and oxygen concentration should follow Stern Volmer relationship The above formula is a general two dimensional polynomial with a flexible degree and was introduced since the basic Stern Volmer did not provide satisfactory curve fit In Uchida et al 2008 a modified Stern Volmer function was suggested 𝐎𝐎𝟐𝟐 𝐏𝐏𝟎𝟎 𝐏𝐏𝐜𝐜 𝟏𝟏 𝐊𝐊𝐒𝐒𝐒𝐒 and 𝐾𝐾𝑆𝑆𝑆𝑆 𝑐𝑐0 𝑐𝑐1𝑡𝑡 𝑐𝑐1𝑡𝑡2 𝑃𝑃0 𝑐𝑐3 𝑐𝑐4𝑡𝑡...

Страница 55: ...ormula has been implemented in the Optode firmware serial no 1000 and above In order to use the Stern Volmer Uchida formula the property called Enable SVUformula must be set to yes The coefficients c0 to c6 are stored in the SVUFoilCoef property A possibility for linear correction of the O2 concentration was also introduced 𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎𝐎 𝐮𝐮𝐮𝐮 𝐂𝐂𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝐨𝟎𝟎 𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝐂𝟏𝟏 ...

Страница 56: ...o three reference sensors that are calibrated with respect to high quality Winkler titrations For a standard multipoint calibration the oxygen is changed from 0 to 120 air saturation in 10 steps and temperature from 1 to 30 C in 4 steps resulting in 40 individual calibration points Based on these data 7 coefficients c0 to c6 in the modified Stern Volmer formula derived by Uchida et al 2008 17 is c...

Страница 57: ...x 8 Illustrations Figure no Description Figure A 9 Drawing Cable 4865 Figure A 10 Drawing Cable 3855 Figure A 11 Drawing Cable 5335 Figure A 12 Drawing Cable 4762 Figure A 13 Drawing Cable 4793 Figure A 14 Drawing Cable 5335 Figure A 15 Drawing Cable 5336 Figure A 16 Drawing Cable 5280 ...

Страница 58: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 58 of 93 Figure A 9 Drawing Cable 4865 ...

Страница 59: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 59 of 93 ...

Страница 60: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 60 of 93 Figure A 10 Drawing Cable 3855 Figure A 11 Drawing Cable 5335 ...

Страница 61: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 61 of 93 Figure A 12 Drawing Free end Cable 4762 ...

Страница 62: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 62 of 93 Figure A 13 Drawing Cable 4793 ...

Страница 63: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 63 of 93 Figure A 14 Drawing Cable 5335 ...

Страница 64: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 64 of 93 Figure A 15 Drawing Cable 5336 ...

Страница 65: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 65 of 93 Figure A 16 Drawing Cable 5280 ...

Страница 66: ... stored in the sensor with a set of new constants by entering them manually into the sensor These constants are delivered on a calibration certificate together with the new foil For multipoint calibrated Optodes the SVU Stern Volmer Uchida formula is used for describing the relationship between phase shift temperature and oxygen concentration Enable SVUformula set to yes The coefficients in this f...

Страница 67: ...ct foil constants and to do a new two point calibration if the foil has been changed or moved CCAP3 Q On the paper the specifications of the AADI Optodes appears to be conservative compared to specifications given for other sensors on the market why A After calibration the sensors normally perform better than the given specifications Aanderaa has a tradition to be conservative when giving sensor s...

Страница 68: ...or in the temperature compensation CCAP8 Q When calibrating which substance should I use to remove the oxygen in the water A At Aanderaa we use Sodium sulphite for this purpose Sodium sulphite rapidly removes the oxygen and as long as crystals of the compound can be seen the oxygen level in the water will stay at 0 Sodium sulphite also has the advantage of being inexpensive and the level of toxici...

Страница 69: ...as heating which will contribute to the self heating Therefore it is better to supply the sensor with 5V in high sampling frequency applications Laboratory testing at 5V has revealed that self heating of the sensor can introduce a 1µM giving lower readings than correct when sampled at a 1 second sample interval This error drops to 0 2 µM for a 5 second interval The error of the internal temperatur...

Страница 70: ...y higher readings Please be aware that there is a high risk of having a different temperature at the foil compared to the temperature of the incorporated temperature sensor in air This might lead to errors in the temperature compensation and to readings that are not correct MR 2 Q What is the reason that several sensors plunged into the same water do not give exactly the same values A Depending on...

Страница 71: ...amage or drift MR 6 Q What is the pressure behaviour of the sensor A The pressure effect is that the sensor reads 3 2 lower readings 1000 meters of water depth which means that at 1000 meters you will have to multiply your readings with 1 032 to get the correct absolute values and at 2000 meters with 1 064 etc This effect is the same for every sensor it is linear and fully instantaneously reversib...

Страница 72: ...ore costly The 120 saturation limit is given for extreme conditions which will rarely occur in reality At 0ºC at a salinity of 0 ppt the 100 saturation reading of water is 457µM It is unlikely that in such waters there would be supersaturation seawater 35 ppt at 0ºC contains 358µM at 100 saturation so here there is margin of up to 140 before the sensor reaches the SR10 measuring limit of 500µM To ...

Страница 73: ... from Aanderaa A No for high pressures beyond 100 bar 1000 m the These are pressure rated to 600 bar 6000 m Please look in the Operating Manual or contact Aanderaa for more information The 4831 Optode is delivered with a underwater matable Subcon connector which is pressure rated to 600 bar MR 13 Q Can I use the sensor for long term measurements in for example an on line system just by connecting ...

Страница 74: ...s hours for the foil to become completely wet or dry Taking a sensor which has been sitting in a dry environment for several hours and introducing it into water to make a spot measurement can lead to an error of maximum 2 Keeping the sensor in a humid environment for at least 24 hours will eliminate this error If you would like to do spot measurements where the sensor is out of the water most of t...

Страница 75: ...ially if you are calibrating sensors You have to take into account the local air pressure and if this is not the same inside your laboratory as at the air pressure you enter during calibration it will introduce errors If placing the sensor in a closed incubator the oscillations should not be detectable MR 21 Q How do I convert oxygen data logged by the Optode to other units A The Optode measures a...

Страница 76: ... manual for more information The formulas from Garcia and Gordon 1992 that can be used to post compensate the measured values are also given in the Optode operation manual MR 24 Q How does the air pressure influence the O2 concentration A If the air pressure is high good weather or created by a ventilation system which gives over pressure more oxygen can dissolve For example if the air pressure is...

Страница 77: ...mary production when e g phytoplankton and sea grass grow in the photic zone where there is light oxygen will be produced this can lead to oversaturation 4 Consumption respiration when there is no light phytoplankton consume oxygen and so do animals e g zooplankton and fish living in the water also when organic material is degraded by bacteria oxygen is consumed 5 Waves if waves are breaking they ...

Страница 78: ... at all naked exposed metal parts with which the anode is in electrical contact with The oxygen consumption can be significant e g during its lifetime normally 1 2 years a 130 g Zn anode mounted on a SEAGUARD RDCP RCM pressure case can consume all oxygen in about 700 l of water Water parcels with lower oxygen concentrations will form and can surround the oxygen sensors and lead to artificial dips ...

Страница 79: ... 100 saturation the foil should be ok If the foil is not ok the sensor will return values that are illogical to what should be expected Then the foil needs to be exchanged new calibration constants entered and a new two point calibration performed Remember that the Optode sensors can also be operated with transparent foils so the black protective layer is not essential If using a transparent foil ...

Страница 80: ...he salinity is 0 ppt and the temperature is 20 C the oxygen concentration should be around 284µM but this value is given for an air pressure of 1013 mbar The saturation values can be obtained from tables and or mathematical formulas given in the Operating Manual If the air pressure is higher for example 1030 you should expect higher readings of about 1030 1013 1013 27 1013 2 7 and if it is lower t...

Страница 81: ...COM port is normally used when I use an USB serial adaptor A This varies from PC to PC and it has to be found out in the operative system SSC 4 Q Is OxyView required to change the sampling interval If not how is it done A No Communication and setting of sample intervals can all be done from a standard terminal program like HyperTerminal All this is explained in detail in the Operating Manual SSC 5...

Страница 82: ...hould I think about if I want to use the Optode mounted on a water column profiling CTD or a towed vehicle A In spite of the relatively slow response time with respect to these applications many customers have chosen to use the sensor mounted on a CTD a profiling vehicle or a towed vehicle Users have selected the Optode mainly because of the long term stability and the absence of pressure hysteres...

Страница 83: ...force water towards the foil and assures a good circulation both when going up and down The Optode of course has to be connected to the CTD with a cable SSC 14 Q When powered on does the Optode expect a XON command before it starts or does it just start sending data A The Optode does not wait for an XON before it starts ...

Страница 84: ... Ooptode an evaluation of its functioning in aquatic environments and multivariate investigations on sensor cross sensitivity were presented in Tengberg et al 2006 Other studies include use on autonomous Argo floats Joos et al 2003 Körtzinger et al 2004 and 2005 Johnson et al 2010 and gliders Nicholoson et al 2008 long term monitoring in coastal environments with high bio fouling Martini et al 200...

Страница 85: ...he capture and maintenance of live deep sea organisms Limnology and Oceanography Methods 3 488 498 4 Hydes D J M C Hartman J Kaiser and J M Campbell 2009 Measurement of dissolved oxygen using optodes in a FerryBox system Estuarine Coastal and Shelf Science 83 485 490 5 Jannasch H W L J Coletti K S Johnson S E Fitzwater J A Needoba and J N Plant 2008 The Land Ocean Biogeochemical Observatory A robu...

Страница 86: ... Rönning S Sommer and A Stangelmayer 2006 Evaluation of a life time based optode to measure oxygen in aquatic systems Limnology and Oceanography Methods 4 7 17 17 Uchida H T Kawano I Kaneko and M Fukasawa 2008 In situ calibration of optode based oxygen sensors Journal of Atmospheric and Oceanic Technology 25 2271 2281 18 Wesslander K P Hall S Hjalmarsson D Lefevre A Omstedt A Rutgersson E Sahlée a...

Страница 87: ...4930 ZPulse Doppler Current Sensor 100 4880 R Temperature Sensor 200 4930 ZPulse Doppler Current Sensor 100 General Change Description Most of AADI s Smart Sensors utilized common communication protocols for use at the RS232 and RS422 interface Two protocols are available Smart Sensor Terminal protocol and the AADI Real Time protocol where the Smart Sensor Terminal protocol is a simple ASCII comma...

Страница 88: ...d by setting the interval to zero Set Interval 0 is now illegal A property called Enable Polled Mode is now used for controlling polled non polled mode 6 The Output property is substituted by a Mode property for changing the operation mode for example Set Mode Smart Sensor Terminal Specific properties control the formatting of the output string for example Set Enable Text no 7 The startup notifica...

Страница 89: ...ases Refer Unisense AS for tabulated physical parameters of interest to those working with micro sensors in marine systems http www unisense com Default aspx ID 1109 Tables Refer Unisense AS for Gas tables with diffusion coefficients solubility of oxygen in seawater density of water versus temperature and salinity and much more ...

Страница 90: ...2017 page 90 of 93 http www unisense com files PDF Diverse Seawater 20 20Gases 20table pdf Copies of Unisense AS tables for solubility of oxygen in seawater are given in Figure A Figure A and Figure A NOTE Refer Unisens AS for more information about the tables ...

Страница 91: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 91 of 93 Figure A 17 Copy of Data Table 6 by Niels Ramsing and Jens Gundersen 100 Oxygen Solubility 1013 mbar pressure ...

Страница 92: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 92 of 93 Figure A 18 Copy of Data Table 7 by Niels Ramsing and Jens Gundersen 100 Oxygen Solubility 1013 mbar pressure ...

Страница 93: ...TD 269 OPERATING MANUAL OXYGEN OPTODE 4330 4831 4835 June 2017 page 93 of 93 Figure A 19 Copy of Data Table 8 by Niels Ramsing and Jens Gundersen 100 Oxygen Solubility 1013 mbar pressure ...

Результаты поиска

Содержание 4330

Отзывы:

Бренды по названию

Популярные бренды

Aanderaa 4330, Руководство по эксплуатации

Результаты поиска

Содержание 4330

Отзывы:

Бренды по названию

Популярные бренды