SC-300 Pro Kit Manual
Contents
1. ccccccc ccc cescescsscsscsscsscssccscssessesssssssssessesseseees 15 Calibration Of pH c cccccccccccceccccsscsscssccsscsscssccsscsscsssssssscssscsucsessecssssscssscsuesessessessesseseseeess 15 Measuring o a OO 16 Measuring Titratable Acidity TA by Titration cccceccccecccccssceccsecsscsscssecssessessssssesseseeeees 16 Finishing oa eroe di cats caseecersd xt coesieatptanenetacraaccsatueiectsvedeneasteneonnaeeseece ctaieatoredemaecdansonsetenitecdsaieatee 18 Warranties Liabilities amp Hazards cccccccccccccccccccsseccceseccccsecceucecsceeccseuuseceeeuscseeeecsseeeseeeaess 19 Appendix A Test Mod e cccceccccccccescesccscescesccsscssccsecsscssecsscsscesccsscssssecsscssessecssssecsesaseesecaseasens 20 Appendix B Sulfite amp TA Adjustmentt 0 0 00cccccccc cece ccccesccssccsscesecssscssessecssecsscsesssessueeseees 22 Appendix C1 Troubleshooting pH and TA Issues 0ccccccccccecesccsscescescsescesecseesseesessseesens 23 Appendix C2 Troubleshooting SO ssues 0 ccccccccccccccccesccesccscesecsscssscssecssesssesssssesseeeseeees 23 US Patent pending SC 300 Pro Kit Manual 1 Version 1 5 Materials provided in the kit 1 Vinmetrica SC 300 SO pH instrument Part number SC 300 1 2 SO Electrode Part number SC 100 3 blue polycarbonate housing 3 pH Electrode Part number SC 200 3 red polycarbonate housing Two 5 mL syringes Two 3 mL polyethylene transfer pipettes One 252. Electrode care Do not touch the glass bulb nor attempt to wipe it with anything When necessary you may gently blot excess liquid away from the electrode surface but avoid directly touching it The pH electrode should always be kept in the liquid storage bottle with its pH storage solution available from Vinmetrica when not in use Rinse the electrode with DI water and gently blot or shake off excess water Push the electrode through the hole in the cap about an inch then gently screw the bottle onto the cap so that the electrode is in contact with the solution in the bottle Assembling the Pro Kit Equipment l Remove the items from their packaging the Lab Support Stand the Vinmetrica Electrode Holder the Double Burette Clamp the 10 mL Glass Burette and the Magnetic Stirrer Carefully pull out the glass burette from its cardboard cylindrical container and out of its bubble wrap Use caution not to exert too much force on the burette as it is fragile and can break 2 For the burette assemble as shown below First remove the attached Teflon stopcock bag which is wrapped around the burette See Figure 4 Open the bag unscrew the red cap remove the black rubber o ring and the red plastic washer from the stopcock assembly See Figure 5 Now insert the stopcock into the slot on the glass burette it should fit snugly See Figure 6 The threaded section on the end of the Teflon stopcock should be protruding through the glass burette slot
3. Vinmetrica SC 300 Pro Kit User Manual Oinmetrica Vinmetrica SC 300 Pro Kit is a simple and robust device that provides high accuracy in determination of sulfite SO2 pH and titratable acidity TA levels in wine These are essential parameters to control in the effort to make high quality wines The Pro kit includes lab accessories for the SC 300 Analyzer Table of Contents Materials Provided in the C0 ce ceecsca neon apceesscsecsmneecescascaacsmon snanaadioennensieszsneoranwnmenacdeceneeeseezonncee 2 Things you will 1c 2 6 teen en Smee ot re a ene ne er reens 2 Why Test for SO2 pH and TA i ccccececcccccesccsscescssccsccsscsscssccsscssessscsscssccsssssesessssseesssseusesessessseeeeeeees 3 Theory of 0 e118 0 en rr renee 4 BS UND OO 5 Setting up the SC 300 for the first tHme cc cceseesseeccecceeeeeeesseecceeceesaeeeseeeeceeeeessaaeseeeeeess 5 Assembhne the Pro Kit Equipe N essenin iea e a 6 Burette Maintenance cccccccccessesscssesscsscsscsscsscsscescesecsecsecsscsscsscsscsscsceseesessecsessecsecsueeeeeeeaees 8 Burc O R IN ceca sacar ca scars neces cg vor TEENA NIEA ON EAT ENANS 9 Instrument Operation 0 cccccc ccc ccc ceccssccsscesccssecsscsccssccsscsccssccsscssecssecssssscssecsessessseessseseeaees 10 1s ot 1 3 ae ee re EE eee eee ee ne 12 Measuring Free Sulfite SO2 by Titration cccccccecccccescesccscsscesccsscssessecsscsscssessuessesssessens 12 Measuring Total Sulfite SO by Titration
4. Reattach the red plastic washer onto the threaded section then the black rubber o ring and finally screw on the red cap See Figure 7 Tighten appropriately but not so much that it is difficult to turn the valve to the open or closed positions Figure 4 The Burette and Figure 5 Disassembly Figure 6 Stopcock Figure 7 Reattached its Teflon Stopcock of Teflon Stopcock inserted into Burette Teflon Stopcock red cap 3 Open the Magnetic Stirrer from its packaging then insert the double AA batteries included For pH measurements or SO amp TA Titrations you can use the 25 mL cylindrical container included SC 300 Pro Kit Manual 6 Version 1 5 with the magnetic stirrer Another option is to replace the cylindrical container with the titration beaker Figure 8 included with the SC 300 Assemble the Lab Support Stand by attaching the long metal rod and screwing it into the large blue metal base We have found that adding a drop of super glue to the threads of the metal rod can prevent loosening of the assembly Then place the magnetic stirrer below the lab support stand as shown below in Figure 8 To attach the Vinmetrica Electrode Holder loosen the thumb screw on the Holder and slide it onto the Lab Support Stand rod Figure 9 then tighten the thumb screw to adjust it to an appropriate height Figure 10 Make sure the Vinmetrica logo can be read upright Attach the Double Burette clamp to the Lab Support Stand using its thumb screw
5. a constant moderate swirling motion If the electrode is not held in a stand hold it against the side of the vessel with one finger and grasp the vessel with the remaining fingers so that the two move together See Figure 23 Verify that the current is less than 50 and the green PROCEED LED is lit See Figure 24 If the current is greater than this and or the red STOP LED is lit and the buzzer sounds your sample has less than 2 ppm SO and there is no need to proceed Verify that your SO has been preconditioned by following step 3 in the Instrument Operation section of the manual Titrate the sample by adding the SO Titrant drop wise from the syringe See Figure 23 or from the burette See Figure 24 being sure to note the starting volume mark on the syringe or burette Try to accomplish the titration as rapidly as possible in 3 minutes or less but be careful near the endpoint so as not to overrun it here dispense one or two drops at a time Be sure to maintain stirring or swirling throughout the entire procedure If the magnetic stirrer turns off turn it back on SC 300 Pro Kit Manual 13 Version 1 5 Figure 23 Manual stirring Figure 24 Automated stirring Figure 25 Make sure Figure 26 Once the device technique Hold the electrode technique Turn on the that the PROCEED beeps for 15 seconds or 20 against the side of the titration magnetic stirrer add SO2 LED is lit You should be sets of beep beep beak
6. current of 50 0 or higher for longer than 5 seconds then the electrode should be preconditioned by allowing it to stand in this solution for a period of time anywhere from 15 minutes to several hours as needed until the current drops below 50 0 and the PROCEED conditions are achieved with the green PROCEED LED lit and no sound is coming from the instrument Normally this preconditioning only needs to be done for the first time the electrode is used See the Appendix C2 for additional testing of the SO function 4 pH mode In this mode the meter measures the pH The pH electrode must be attached If the instrument has not yet been calibrated the message doCal scrolls across the screen and you need to do a calibration see Calibration of pH below We recommend re calibrating the instrument for pH once each day of use Warning Be careful not to press ENTER when the pH electrode is attached while the instrument is in SO mode as this can potentially damage the pH electrode If this does happen and the pH electrode does not respond correctly place it into the pH 4 Reference solution for an hour and it should return to normal function J TA mode This is for titration in determining titratable acidity TA As in the pH mode the pH is displayed and the pH electrode must be attached The green PROCEED LED is lit if the SC 300 Pro Kit Manual 10 Version 1 5 pH is below 8 2 while the red STOP LED is lit if the pH is 8 2 o
7. handle is horizontal When filling the burette make sure the SO gt titrant has completely filled the bottom of the burette including the tip Sometimes bubbles can be trapped in the tip of the burette but can usually be dislodged by opening and closing the stopcock while the burette 1s above a waste container If you spill any titrant on the outside of the burette be sure to clean it up with a paper towel or dry rag If the spilled titrant is not cleaned from the outside of the burette you may introduce these spilled titrant droplets into the wine sample leading to an inaccurate reading Be sure to record your starting burette or syringe volume refer to Burette Reading section under the Setup section for how to measure accurately SC 300 Pro Kit Manual 12 Version 1 5 Place 25 mL of wine or must in the titration vessel We recommend using the 25 mL sampling pipette provided in the kit draw the sample up to the 0 mL mark and then dispense the sample into your titration vessel by letting the tip of the pipette touch the side of the vessel while the sample drains See Figure 21 NEVER pipette any reagents by mouth Also make sure the pipette you are using is completely clean before submerging into your wine sample Using the transfer pipettes see Figure 22 add about 2 mL Acid Reagent and 2 mL Reactant solution to the titration beaker the two transfer pipettes should come with red and yellow labels with red for the Acid Reagent and yellow for
8. instrument using something metallic like a paper clip or pin to connect the center hole of the connector to its outer sheath With the input shorted out the reading should be pH 7 00 0 05 If out of this range the meter is probably bad Contact us at info vinmetrica com or tel 760 494 0597 Bear in mind that this test is not 100 fool proof the instrument might still have trouble reading pH values different from 7 00 but generally if this test passes it is much more likely to be an electrode problem SC 300 Pro Kit Manual 24 Version 1 5 Help What do I do if my pH electrode was attached to my SC 300 when in SO mode Is my pH electrode broken No don t worry your pH meter should still work To fix it leave your pH electrode in the pH 4 reference solution for an hour and it should return to normal function Enabling SO mode with the pH electrode attached could cause the pH electrode to wear out more quickly Because of its design SO mode cannot be accessed unless you press ENTER after pressing the MODE button this is another safeguard we installed to prevent this from becoming a problem Appendix C2 Troubleshooting SO Issues How stable are the reagents The SO reagents and the pH TA reagents are all warranted to last for 6 months We have found that in fact except the TA Titrant our reagents are stable for well over 12 months if stored tightly capped out of the heat and direct sunlight And of cou
9. the detergent mix approximately half a gram about an 1 8th of a teaspoon with about 50 milliliters mL of distilled water into a small bottle We recommend capping the bottle and shaking well for a minute or until the detergent is dissolved Bubbles may form but the detergent will still be effective The detergent solution should be made fresh every time you clean the burette as it loses its potency quickly if stored as a liquid After you have run distilled water through your burette close the stopcock and fill with the Burette Detergent solution You can open and close the stopcock over a waste bucket or sink to allow the solution to pass into the tip of the stopcock We recommend letting this detergent solution sit in the burette for one hour Dispense the detergent solution then rinse the burette with distilled water twice more During this time we recommend opening and closing the stopcock to make sure the stopcock is turning easily If it is not remove the stopcock and clean it thoroughly Once drained allow to hang dry by hanging the burette upside down with the stopcock in the open position Once the burette is dry cover the top opening with a piece of tape This will prevent dust from getting in that can cause aberrations when reading the burette Remove the tape when you re ready to titrate SC 300 Pro Kit Manual 8 Version 1 5 Burette Reading ALWAYS use eye protection and preferably gloves latex or nitrile when using glassware an
10. the rubber neck gently so the electrode is further stabilized into the slot You are now ready to titrate SC 300 Pro Kit Manual 7 Version 1 5 Note The magnetic stir bar that is placed within the 25 ml cylindrical container or titration beaker can potentially damage the SO and pH electrodes When adjusting the height of the electrodes make sure that the stir bar in the beaker is below the bottom of the electrode You do not want the spinning magnetic stir bar to strike the SO or pH electrode Figure 12 The glass Figure 13 The burette Figure 14 The glass Figure 15 The Pro Kit burette should be placed sits firmly between the burette tip can be slid into Assembly is complete Go between two sets of notches of the four the Electrode Holder s take some measurements spring arm knobs on the spring arm knobs of the front open slot for Double Burette Clamp Double Burette Clamp accurate titrations Burette Maintenance Keep the burette clean and wash with deionized distilled water when you are finished using the burette This is especially important for TA titrations because the TA Titrant is caustic and can etch the burette Every so often you will want to clean your burette with a cleaning solution to maintain accuracy of the burette The included 2 grams of Burette Detergent is specially formulated to clean glassware The dry detergent ships in an Eppendorf tube that has markings with approximate half gram increments Upon first receiving
11. to adjust for height as shown in Figure 11 below Usually with the burette attached to the Double Burette Clamp you may need to adjust both of them to the right height to read it properly Figure 8 The Magnetic Figure 9 The Vinmetrica Figure 10 The thumb Figure 11 The Double stirrer and beaker with the Electrode Holder slides screw makes adjusting Burette Clamp slides pH electrode inserted into onto the Lab Support The Vinmetrica Electrode easily onto the Lab the Electrode Holder Stand Holder s height easy Support Stand to the wine sample Carefully open the Double Burette Clamp s spring arms with your thumb and forefinger and place the burette in between the four indentations in the double burette clamp s spring arm s plastic knobs See Figure 12 Slowly release the clamp spring to secure the burette between these four spring arm plastic knobs See Figure 13 You can adjust the burette at any time by raising and lowering it within the spring arm clamps of the Double Burette Clamp When making these adjustments hold onto the burette and do not apply too much force to it as the burette is delicate The burette tip can be placed into a convenient slot on the Vinmetrica Electrode Holder See Figure 14 to make it easier to titrate Finally insert the electrode that you wish to use into one of the open side slots as seen in Figure 8 Once the rubber neck of the electrode is sitting on top of the electrode holder you can press down on
12. C 300 Pro Kit Manual 22 Version 1 5 Appendix C1 Troubleshooting pH and TA Issues I can t calibrate the pH on my SC 300 When calibrating your pH electrode remember these points l The displayed pH may not be correct until after you press ENTER 2 If the instrument signals stable pH but displays Bad Cal after pressing ENTER try laying it flat on the table when the next stable signal is signaled press the ENTER button quickly without handling the instrument Sometimes the instrument may pick up noise from its environment particularly if you handle it at the last second while it s trying to achieve a stable reading This sensitivity is usually only an issue during calibration 3 If values appear to drift leave the electrode in the pH 4 01 reference solution for 30 minutes 4 If you intend to read pH values in samples that are at a different temperature than ambient it s best to have your reference solutions at that temperature also before calibrating 5 Finally refer to the next FAQ question if these steps do not help What should I do if my pH electrode is acting sluggish erratic and is difficult to calibrate Reconditioning and cleaning of pH electrodes Even in normal use and storage performance of pH electrodes may show deterioration over time which typically shows up as noisy erratic or sluggish electrode readings and or difficulty calibrating Assuming the meter itself is working see Meter test
13. METRICA S BREACH OF THESE TERMS AND CONDITIONS BREACH OF WARRANTY NEGLIGENCE STRICT LIABILITY OR OTHER TORT WITH RESPECT TO THE MATERIALS OR ANY SERVICES IN CONNECTION WITH THE MATERIALS IS LIMITED TO AN AMOUNT NOT TO EXCEED THE PRICE OF THE MATERIALS IN NO EVENT SHALL VINMETRICA BE LIABLE TO BUYER FOR ANY INCIDENTAL CONSEQUENTIAL OR SPECIAL DAMAGES INCLUDING WITHOUT LIMITATION LOST REVENUES AND PROFITS HAZARDS AND TOXICITY All Materials offered by Vinmetrica are intended for use by individuals who are familiar with laboratory procedures and their potential hazards The Materials contain chemicals which may be harmful if misused Due care should be exercised with all Materials to prevent direct human contact Glassware can break and chemicals can splash during experiments Always use safety glasses We strongly recommend using nitrile or latex gloves and wearing long pants long sleeves and closed toed shoes Keep out of reach of children Vinmetrica 1945 Camino Vida Roble Suite Carlsbad CA 92008 www vinmetrica com 760 494 0597 info vinmetrica com Copyright 2010 13 Sportsman Consulting LLC DBA Vinmetrica All rights reserved SC 300 Pro Kit Manual 19 Version 1 5 Appendix A Test Mode Test Mode provides various special functions that may be useful in testing the device for example if troubleshooting is necessary Test Mode is entered when the POWER button is pressed longer than 2 seconds while turning the
14. below then there are two main causes for this l Clogging of the reference junction most likely 2 Fouling of the glass membrane happens occasionally or after prolonged service The following procedures will often provide renewed stability and pH sensitivity If the electrode cannot be restored by one of these methods it needs to be replaced Unblocking the reference junction The reference electrode junction is usually the problem when the electrode can t calibrate in its expected ranges This junction is a fine pored frit that allows electrical contact of a reference electrode with the solution being tested It can become clogged over time SC 300 Pro Kit Manual 23 Version 1 5 Soak electrode in hot NOT boiling water about 60 C for 5 10 mins Allow to cool to room temperature then place in pH 4 reference solution for 5 minutes Try to recalibrate If this does not work try remedy 2 Place the pH electrode into the pH storage solution available from Vinmetrica part number SC 200 10 or a solution of 2 5M KCI with optionally added 0 01M KHP at 60 C and allow electrode and solution to cool to room temperature then place in pH 4 reference solution for 5 minutes Try to recalibrate If this doesn t work try remedy 3 Soak in 0 1M HCI note this can be made by diluting 1 mL of the SO Acid Solution with 20 mL DI water or 0 1M nitric acid HNO3 for 1 hour Rinse with DI water then place in pH 4 reference solution
15. button to resume from where you were Electrodes Attach the desired electrode pH or SO Figures 2 amp 3 via the BNC connector protruding from the top Be sure to secure the electrode plug to the BNC connector to insure proper function Figure 2 Attach the Electrode Figure 3 Be sure the Electrode you are using to the BNC attachment is screwed into place connector on the SC 300 on the BNC connector SO electrode Remove any protective cover from the electrode tip some electrodes are shipped without one This cover is for shipping protection and need not be used routinely Put the electrode on its side or hang it from an electrode stand if you have one The SO electrode blue is sturdy with its plastic housing but do take care not to let things touch or strike the platinum wires they are somewhat fragile and will break if bent and straightened repeatedly Electrode care When done always rinse with DI water and let air dry There is no need to store the SO electrode in any kind of solution SC 300 Pro Kit Manual 5 Version 1 5 6 pH electrode Attach the pH electrode via the BNC connector on the top of the SC 300 see Figures 2 amp 3 A note about the pH electrode The pH electrode is fragile and should always be handled carefully Remove the liquid storage bottle by unscrewing the cap first then gently pulling the bottle followed by the cap off the electrode Rinse the electrode in a little distilled water before each use
16. d chemical reagents To get the most accurate results when titrating there are a few things to keep in mind We recommend reading from the bottom of the meniscus See Figure 17 on the following page First use a thick sheet of white paper note card or the back of a business card and draw a black band down the center of the paper about an inch and a half thick See Figure 16 When taking a measurement hold the paper about an inch behind the burette and the black band about a half an inch below the meniscus See Figure 18 This provides a clear view of the bottom of the meniscus which helps make a precise consistent measurement Second when filling the burette make sure the titrant in most cases this will be either the SO Titrant or the TA Titrant has completely filled the bottom of the burette including within the tip Sometimes bubbles can be trapped in the tip of the burette but can usually be dislodged by opening and closing the stopcock while the burette is hovering over a waste container We also recommend washing a couple of milliliters of the titrant you are using through the burette to remove any excess water or contaminants that may remain from a previous titration Finally make sure there are not any large bubbles in the burette after filling If there are cover the top of the burette with some saran wrap or parafilm if you have it and make sure the stopcock is in the closed position Then take the burette out of its clamp and hold the
17. e is simply determined by placing the calibrated pH electrode into a sample and reading the value TA is determined by titrating a5 mL sample of wine to an endpoint pH of 8 2 with the TA titrant 0 133N NaOH from the syringe in the kit From the known concentration of the TA titrant and its volume required to reach the endpoint the TA is simply calculated results are in units of g L tartaric acid SC 300 Pro Kit Manual 4 Version 1 5 Setup Setting up the SC 300 for the first time l The SC 300 See Figure 1 runs on two standard AA batteries alkaline cells recommended To insert the batteries open the battery housing on the bottom of the back of the unit by removing the two screws and gently prying off the lid Install the batteries with the negative end contacting the coiled springs and the positive end contacting the raised metal inserts then close the housing If desired you can prop the unit up using its folding stand Low Battery Detection When the battery level is getting low the instrument will show a low battery icon on the upper left side of the display but continues to operate without impairment to any function Replace the batteries as soon as practicable When the battery level drops too far the instrument does not operate It rapidly flashes the low battery icon for 3 0 seconds beeps and shuts itself off Auto Shut off The SC 300 shuts off after 30 minutes If this happens unexpectedly just press the POWER
18. e syringe or burette being sure to note the starting volume mark on the syringe or burette During the titration the pH will gradually rise from its starting value below 4 usually As you approach pH 7 go slowly in adding successive drops of titrant so as not to overrun the endpoint Be sure to mix thoroughly after each successive drop of titrant Take the endpoint as the first addition of TA Titrant that causes the pH to stay above 8 2 for longer than 15 seconds The red STOP LED and the beeper will provide additional indication of the endpoint See Figure 30 Read the endpoint volume off of the syringe or burette To silence the beeper after the endpoint select pH mode or turn off the instrument 10 Calculate the TA value as V 0 133 75 TA g LTartaric where V mL Titrant needed to reach the endpoint 0 133 normality of the Titrant mL sample If you use 5 mL of sample as directed and the Titrant is 0 133 N as supplied then the calculation is simply TA 2x V i e 2 times V Finishing up 1 Turn off the instrument 2 Rinse the SO electrode and syringe with distilled water Let air dry 3 Be sure to rinse and store the pH electrode in its storage solution as directed under Setting up the SC 300 for the first time item 6 4 Store all reagents tightly capped and away from heat and sunlight gt Discard waste samples and solutions in accordance with local regulations Acidic solutions can be neu
19. e the electrode in the solution to be tested Be careful not to let the electrode strike any surfaces 4 Allow the pH reading to stabilize Typically this takes about 10 15 seconds Read the pH value on the display Note Once you ve completed the pH test you can start the TA test Start with precisely a 5 mL wine sample before beginning the pH amp TA combined measurement You can use a clean 5 mL sampling pipette provided in the kit to pipette this amount Measuring Titratable Acidity TA by Titration l If you are working with a sample of must we recommend homogenizing your sample in a blender before proceeding otherwise your TA values can be very inaccurate Take 100 mL or more of your must and put it in a blender on high for 30 seconds Allow solids to settle for 2 minutes before sampling or use a cheese cloth or mesh strainer to remove solids 2 Fill the syringe by drawing up the TA Titrant 0 133N NaOH Expel bubbles and set the plunger on the syringe to a readable point preferably the 5 0 mL point Note the 5 0 mL setting allows determination of up to 10 g L TA in a standard 5 mL wine sample If you are using the burette use the syringe to dispense the TA titrant into the top of the burette Make sure the burette stopcock is in the closed the red handle is horizontal position When filling the burette make sure the TA titrant has completely filled the bottom of the burette including the tip Sometimes bubbles can be trapped in t
20. ectrode in the following steps See Figure 28 Rinse the electrode briefly with DI water Insert the electrode into the titration vessel so that the tip is fully submerged to just above the circulation gaps cutouts at the tip of the electrode If you are stirring manually begin now use a moderate swirling motion If the electrode is not held in a stand hold it against the side of the vessel with one finger and grasp the vessel with the remaining fingers so that the two move together while swirling See Figure 27 Figure 27 Manual stirring Figure 28 Automated Figure 29 Make sure that Figure 30 Once the pH technique Hold the stirring technique Turn on the green PROCEED arrives at or passes 8 20 electrode against the side of the magnetic stirrer add LED is lit You should be you are done with the the titration beaker and TA Titrant by slowly reading a pH close to what titration The red STOP swirl gently add TA Titrant opening the burette you expect your wine is at LED will be lit and the with other hand stopcock valve You are ready to titrate instrument will be beeping SC 300 Pro Kit Manual 17 Version 1 5 8 Verify that the pH is less than 7 and the green PROCEED LED 1s lit see Figure 29 If the pH is greater than this and or the red STOP LED is lit and the beeper sounds your sample has less than 0 1 g L TA and there is no need to proceed 9 Titrate the sample by adding the TA Titrant drop wise from th
21. er and swirl gently add Titrant by slowly opening the reading close to 0 0 when you are done with the SO2 Titrant with other hand burette stopcock valve you first start You are titration The red STOP now ready to titrate LED will also remain lit 10 During the titration the LCD display will show transient currents the red STOP LED will 11 12 briefly illuminate and the beeper will sound beep beep These transient indicators will last longer and longer as you approach the endpoint Figure 26 Take the endpoint as the first addition of Titrant that causes the display to exceed 50 and the red LED and beeper to stay on for longer than 15 seconds or a count of 20 sets of beep beep It is important to maintain stirring or swirling to detect the endpoint well Do not add titrant while the red STOP LED is lit Read the remaining titrant volume off of the syringe or burette Calculate the volume of titrant used V using the Syringe Starting volume minus final volume e g Burette final volume minus starting volume e g V 5 0 mL 3 5 mL 1 5 mL The free SO content is calculated in units of parts per million ppm as 64 V N 1000 ppm Free SO 2 S Where V mL SQ Titrant needed to reach the endpoint N normality concentration of the Titrant and S mL of your wine sample Tf you use a 25 mL wine sample as directed and the SO Titrant s normality is 0 0156 as supplied in the kit then
22. evel of the stir bar SC 300 Pro Kit Manual 11 Version 1 5 Procedures Measuring Free SQ by Titration l Make sure the SO electrode is attached and preconditioned as described in step 3 of the Instrument Operation section Turn on the instrument and select SO2 mode with the MODE button Press ENTER to confirm selection of SO2 mode Figure 19 P Figure 19 Once in SO gt Figure 20 Withdraw Figure 21 Dispense 25 Figure 22 The transfer MODE the instrument the titrant from its bottle mL of your wine into the pipette One full squeeze should read using a clean 5 mL titration beaker using the of the transfer pipette in P E55 EnkEr syringe If you are using 25 mL sampling pipette either the Acid solution Press ENTER to activate the glass burette use the Make sure this is clean or Reactant should be SO MODE syringe to fill it before putting the pipette approximately 2 mL into your wine container 2 Fill the syringe by drawing up the SO Titrant the bottle with the blue label Figure 20 Expel bubbles and set the plunger on the syringe to a readable point preferably the 5 0 mL point Make sure the outside of the syringe is dry to minimize any inaccuracies Note the 5 0 mL setting allows determination of up to 100 ppm SO in a standard 25 mL wine sample If using the burette use the syringe to dispense the SO titrant into the top of the burette Make sure the burette stopcock is in the closed position where the red
23. for 5 minutes Try to recalibrate If this does not work try remedy 4 Soak in 1 10 dilution of bleach in a 0 1 0 05 solution of liquid detergent in hot water with vigorous stirring for 15 mins Rinse with DI water then place in pH 4 reference solution for 5 minutes Try to recalibrate Cleaning the pH electrode s glass membrane The glass bulb is a thin membrane of a special kind of glass that actually does the job of responding to the pH of the solution It can sometimes become dirty and poorly responsive I Immerse electrode tip in 0 1M HCI see above for how to make for about 15 secs rinse with distilled water then immerse in 0 1M NaOH you can use a little of your TA Titrant for this for another 15 sec Cycle the electrode through these solutions several times rinsing with DI water in between then rinse and check for performance in pH buffer 4 00 and 7 00 Some other tricks protein deposits can be removed by soaking in pepsin in 0 1M HCI for 15 mins Inorganic deposits may be removed by soaking in 0 1M tetrasodium EDTA solution for 15 mins Grease and oil deposits may be removed by rinsing the electrode in mild detergent in methanol solution Instrument test You want to be sure that the instrument is responding correctly A quick test is to simply short out the electrode connector 1 2 Disconnect the electrode and put the instrument in pH mode Short out the electrode connector at the top of the
24. he tip of the burette but can usually be dislodged by opening and closing the stopcock while the burette is above a waste container If you spill any SC 300 Pro Kit Manual 16 Version 1 5 TA titrant on the outside of the burette be sure to clean it up with a paper towel or dry rag If the spilled titrant is not cleaned from the outside of the burette you may introduce these spilled titrant droplets into the wine sample leading to an inaccurate reading Be sure to record your starting burette or syringe volume Caution the TA Titrant is caustic and can cause damage to clothing skin and eyes We recommend use of laboratory safety glasses and latex or nitrile gloves during this procedure If any solutions contact skin or eyes flush with plenty of water Place 5 0 mL wine or must in the titration vessel 100 mL polypropylene beaker We recommend using the 5 mL pipette provided in the kit draw sample up to the 0 mL mark then dispense the sample into your titration vessel by letting the tip of the pipette touch the side of the vessel while the sample drains For best accuracy do not blow out the liquid that remains in the tip Add about 15 ml of deionized DI water distilled water Turn on the instrument Make sure the pH electrode is attached If necessary calibrate it as described above Select TA mode with the MODE button If you are using a magnetic stirrer turn it on to stir at a moderate rate Be sure the stir bar will not strike the el
25. instrument on Remove the pH electrode if it is attached Test Mode is organized into sections Press the POWER button briefly to move to the next section After the last section Test Mode restarts the first WARNING DO NOT MOVE THROUGH SECTIONS WITH THE pH PROBE ATTACHED This can damage the electrode Only connect the pH electrode if needed in section 2 or 4 Always remove the pH electrode before leaving these sections Combinations of the yellow MODE LEDs are illuminated to indicate the section number as shown in the table below The Stop LED red is illuminated when an error is detected by the instrument The Proceed LED green is illuminated to indicate no error detected The green LED does not guarantee proper functioning it only indicates that no problem could be automatically detected The user should make careful observations to discern proper operation To exit Test Mode hold the POWER button down 5 10 seconds until the instrument shuts off If the device does not shut off after 10 seconds of holding down the button move to the next section by releasing then pressing again the POWER button briefly then try to exit again 1 Version None The version number of the instrument software is displayed The instrument goes through a 2 Burn in None continuous burn in cycle exercising relay sound LEDs and display 3 pH pH probe or precision An uncalibrated pH level is shown in two voltage source Do alter
26. mL serological sampling pipette Figure 1 The SC 300 instrument One 5mL serological sampling pipette 100 mL polypropylene titration beaker SO Reagent set Part number SC 100 2 SO Titrant solution 0 0156N Acid reagent Reactant solution 10 pH TA reagent set Part number SC 200 2 pH 4 01 Reference solution pH 7 00 Reference solution TA Titrant 0 133N NaOH 11 Lab Support stand the large blue metal base with its long metal rod Part number SC 300 3 12 Vinmetrica Electrode Holder Part number SC 300 8 13 Double Burette Clamp Part number SC 300 6 14 10 mL Glass burette with Teflon Stopcock with 2 grams of Burette detergent Part number SC 300 7 15 Magnetic Stirrer includes two AA batteries stir bar and 25 mL cylindrical container Part number SC 300 4 ee Ss Things you will need Two standard AA batteries alkaline type pA Distilled water which usually can be found at your local grocery store It s handy to have a wash bottle for rinsing Rinse bottle available from Vinmetrica Part number SC 100 17 3 Optional IN Sodium Hydroxide solution Gf you want to do total SO2 Available from Vinmetrica Part number SC100 7 SC 300 Pro Kit Manual 2 Version 1 5 Why Test for SO pH and TA Testing for sulfite SO2 is crucially important for making sure your wine does not spoil by oxidation or from microbial growth Having the proper SO level in your wine gives you this protection By monitoring your SO gt le
27. mentation the pH can increase somewhat and should be monitored Typically wine pH and TA are inversely related when pH goes up TA goes down and vice versa Adjustments may be made to your wine to prevent wine instability See Appendix B for more information on adjustments SC 300 Pro Kit Manual 3 Version 1 5 Theory of Operation 1 Sulfite S02 The SC 300 with the SO electrode and reagents provided can be used to determine sulfite levels in wine musts and other samples It relies on the Ripper titration based on the quantitative reaction of the SO with iodine generated during the titration which oxidizes the SO in the sample under acid conditions IO 5I 6H gt 3 3HO generation of iodine 12 from iodate IO SO bL H2O gt 21 SO 3 2H reaction of SO and iodine When all the SO is titrated at the endpoint excess iodine appears in solution This is detected as current with the SO electrode and signaled by audible and visual indicators The endpoint is much more sensitive than the starch color change commonly employed for Ripper titration and it is sharp and clear even when titrating red wines and musts From the known concentration of the titrant and its volume required to reach the endpoint the free SO2 is simply calculated 2 pH and TA The SC 300 kit also provides a pH electrode and reagents for calibration and determination of pH and titratable acidity TA values in wines and other samples The pH valu
28. n occur If it doesn t you may have an electrode problem read in the next section below how to fix this Now add one drop of a concentrated sulfite solution 1 10 1s fine and verify that the STOP signal ends and the PROCEED light illuminates If this happens your electrode is probably OK as well 4 Finally you can check your SO reagents with the ascorbic acid vitamin C test located on our website vinmetrica com FAQ Sometimes when the SO electrode is first shipped it can be shipped hot A hot electrode is one that is overly sensitive this can be fixed by pre conditioning your SO electrode To pre condition your electrode l First attach the SO electrode to the SC 300 analyzer turn the power on and press the MODE button until the instrument is in SO2 mode then press ENTER Put 20 mL of distilled water de ionized water in a beaker and add half a bulb squeeze of the acid solution half a bulb squeeze of the reactant solution and let the SO electrode sit in this solution 2 Then add one drop of 10 potassium metabisulfite solution KMBS to the beaker with the electrode in it Swirl gently The instrument LCD should now read 0 0 in units of nanoamps or close to it If it is reading significantly higher than 20 on the screen let the electrode sit in the solution for half an hour 3 After half an hour rinse the electrode with distilled water Put it in about 20 mL of distilled water Again add half a bulb squeeze of each
29. nating parts First the integer not exceed 0 5 V portion of pH level is shown 1 to 14 Next three decimal places are shown Readings above 14 000 are shown as Readings below 0 000 are shown as SO probe or SO The SO current in nanoamperes 1s probe simulator e g displayed For values under 10 one 450 kOhm resistor decimal place is shown SC 300 Pro Kit Manual 20 Version 1 5 ex Section Equipment Required 5 pH pH probe or precision The raw voltage output from the Voltage voltage source Do instrument s pH amplifier is displayed as not exceed 0 5 V X XX volts Readings can range from 0 00 to 4 10 6 SO SO probe or The raw voltage output from the Voltage SO probe simulator instrument s current amplifier is displayed as X XX volts X XX if less than 1 00 7 DAC None The Digital Analog Converter DAC is Test Disconnect probe cycled through its 32 levels Note Ignore red LED error indication 8 Battery Install two AA The battery voltage is displayed as X XX Voltage batteries volts 9 Character None Every ASCII character space to is displayed Due to the limitations of the 7 segment format some characters are not used by the software 10 Number The display cycles through showing Display every possible digit and every decimal point 11 Sound The beeper is turned on continuously Test SC 300 Pro Kit Manual 21 Version 1 5 Appendix B Sulfite and TA Adjus
30. ne of the reference solutions e g pH 4 01 4 The instrument will determine which calibration solution is being used and will display the apparent pH value This may be different by as much as 0 40 from the value of the reference solution e g the LCD may display 4 41 when the pH electrode is sitting in the pH 4 01 reference solution When the pH level is sensed as stable the nominal value is shown on the display flashing and the CAL LED flashes to convey that calibration for this value 1s ready Press the ENTER button to accept the calibration 5 The display stops flashing scrolling the message Lood CAL and four beeps are rapidly sounded to indicate success Note if an error occurs during this process the message SC 300 Pro Kit Manual 15 Version 1 5 bAd CAL will scroll and a single beep will sound the instrument will then continue to wait for a stable pH level Repeat step 4 Following the Good CAL message the display will now show the calibrated pH value 6 Now rinse the electrode again and place it in the second member of the calibration set e g pH 7 00 reference solution Repeat the process to get a second Lood LAL message Exit into pH or TA mode Measuring pH 1 Make sure the pH electrode is attached Calibrate it as described above if necessary Select pH mode with the MODE button 2 Rinse the pH electrode with DI water Gently shake off or carefully blot away excess liquid 3 Plac
31. o seconds at start up will cause the instrument to enter Test Mode see Appendix A The instrument will go through a power up sequence After a few seconds the instrument will start in whatever mode was last selected The mode is indicated by the yellow LED panel on the left Select the desired mode by pressing the MODE button Zi SO mode This is for titration in determining ppm of SO see below under Procedures The SO electrode must be attached Warning The pH electrode can be damaged by connecting it to the instrument in SO2 mode As a safety precaution you must press the ENTER button after selecting SO mode to confirm that the SO electrode is attached before the mode will be enabled However scrolling through the MODE selections such that you pass by the SO selection with a pH electrode attached is safe as long as you do not press ENTER to confirm the SO mode After pressing ENTER with the SO electrode attached you should see the display show a value less than 50 usually 0 0 and the green PROCEED LED should be on 3 Precondition the SQ Electrode We recommend that you precondition your SO electrode before you use it for the first time With the SO Electrode attached and the SC 300 instrument in SO2 Mode place the SO electrode in 20 mL H20 and add 2 drops of Acid Solution Stir moderately If the instrument registers the STOP condition with the red STOP LED Itt the beeper sounding and the LCD displaying a
32. of the acid solution and the reactant and swirl in the usual way keeping constant motion The instrument may or may not indicate STOP as above If it does not add a drop of the SO Titrant solution This should make the STOP condition occur If it doesn t you may have an electrode problem 4 Now add one drop of KMBS solution 1 10 is fine swirl and verify that the STOP signal ends and the PROCEED light illuminates If this is the case your electrode has been conditioned If the electrode is still hot and the PROCEED light does not illuminate let it sit in 20 mL of distilled water with a half bulb full of the acid solution for a few hours Now repeat the test from step 3 If it works great If not call us and we will try to troubleshoot or replace your electrode Technical assistance info vinmetrica com tel 760 494 0597 SC 300 Pro Kit Manual 26 Version 1 5
33. owder as your sulfite additive We recommend double checking your calculations and choosing the appropriate Desired molecular SO level usually 0 8 mg L after primary fermentation Once you have added the amount of sulfite that fits to your methods stir your wine thoroughly and take another SO2 measurement If the measurement matches the Desired level of free SO then you are done otherwise make incremental additions and repeated SO measurements until you reach your desired level Adjusting TA in your wine We recommend adjusting your titratable acidity levels by adding tartaric acid for non grape wines fruit acids can be used but remember additions of malic acid if done improperly can make wine overly sour or tart If your wine s pH is too high indicating low acidity and TA levels too low you can add tartaric acid to decrease the pH and increase TA By measuring TA you can figure out how much tartaric acid to add without making your wine overly tart or sharp If your TA is too high some winemakers like to do a cold stabilization which results in precipitation of tartaric acid before bottling to decrease the tartness Another method to decreasing your TA level is to add calcium carbonate or potassium carbonate CaCO or K2CQO3 For the chemically inclined we recommend Zoecklein s book Wine Analysis and Production which goes over theory and practice behind these adjustment techniques and many wine analytical techniques S
34. r greater see below under Measuring TA by Titration 6 CAL mode This is for calibrating the pH electrode which must be attached The display initially shows CAL for a few seconds as it prepares to read pH and lets readings settle Thereafter the display shows the measured pH level with two decimal places 7 Calibration works with one of the following reference calibration sets pH 4 01 and 7 00 or 4 7 pH 7 00 and 10 00 or 7 10 pH 3 00 and 7 00 or 3 7 Vinmetrica recommends use of the pH 4 7 Reference Solution set provided with the kit 8 The magnetic stirrer has two modes Pressing the light bulb button on the magnetic stirrer activates a light underneath the sample and the stirrer The power button activates just the stirrer After pressing either button the stirrer remains active for 60 seconds a feature to conserve its batteries If during the titration it turns off simply press the button again for it to continue We recommend using the light mode because it helps us indicate when the stirrer stops Plus when doing TA titrations watching the wine turn from deep red to dark green is cool Note When using the magnetic stirrer be sure that the electrode does not touch the spinning stir bar as this can potentially damage the glass bulb of the pH electrode or the platinum wires of the SO electrode If you are using the Vinmetrica Electrode Holder adjust the electrode s height so that its probe end 1s above the l
35. rse these reagents will last much longer if not cross contaminated with each other How can I check the accuracy of my reagents It s rare that the SO reagents go bad but if you are concerned about it run the Ascorbic Acid Test method located in the FAQ section of the website to check your SO gt reagents If you are worried about your TA Titrant you can run the KHP test also located on the Vinmetrica website in the FAQ section under Manuals Tests and How To Videos at vinmetrica com FAQ I m getting strange results in SO mode how do I know if my instrument is working correctly For SO2 measurements with the SC 300 there are several quick tests you can do to make sure the instrument is not faulty 1 Be sure the battery is good per the manual s instructions 2 Short out the terminals on the BNC connector at the back using a paper clip or similar metal piece The device should indicate STOP with its red LED and buzzer or beeper If this does not happen there may be a problem with the instrument contact us for more information SC 300 Pro Kit Manual 25 Version 1 5 Sh Connect the electrode and put it in about 20 mL of distilled water add about 1 ml half a bulb squeeze of each of the acid solution and the reactant and swirl in the usual way keeping constant motion The instrument may or may not indicate STOP as above If it does not add a drop of the SO Titrant solution This should make the STOP conditio
36. saran wrapped end tightly Rotate and invert the burette to allow the bubbles to move out of the column of titrant Once the bubbles have been displaced you are ready to titrate oe tts jo Figure 16 On a thick white Figure 17 The Meniscus of the Figure 18 Reading the Meniscus of sheet of paper or a business card water column This curve is the water column is easier and more use a black marker to draw a formed because of interactions precise if you use the paper with the band approximately an inch and of water with the glass burette black band held up an inch behind the a half thick This card will assist We recommend measuring the burette and its black band 1 2 an inch you in reading the burette titrant volume from the bottom below the meniscus In this picture the accurately of the meniscus In the picture value from Figure 17 is further the value is about 3 27 mL resolved to 3 26 mL Before beginning the titration record the starting titration volume using the thick white paper with the black band and then begin titrating slowly Record the final titration volume using the same technique You can also checkout these websites for more burette info http www titrations info pipette burette or http www csudh edu oliver demos buretuse buretuse htm SC 300 Pro Kit Manual 9 Version 1 5 Instrument Operation l Turn on the instrument by pressing the POWER button briefly Note depressing the POWER button longer than tw
37. the Reactant It is not necessary to be extremely accurate in this step with these pipettes 2 mL is roughly the amount that fills the pipette up to the 2 mL mark after a single thorough squeeze of the bulb To preserve the shelf life of these reagents take care not to cross contaminate the transfer pipettes If they do get contaminated rinse them off with distilled water and let air dry Caution the Acid reagent is corrosive and can cause damage to clothing skin and eyes The Reactant solution should not be ingested ALWAYS use safety glasses We recommend the use of laboratory latex or nitrile gloves during this procedure If any solutions contact skin or eyes flush with plenty of water If you are using a magnetic stirrer turn it on to stir at a moderate rate The Magnetic Stirrer provided with the SC 300 Pro Kit operates at a suitable preset speed Make sure your electrode is not being struck by the spinning stir bar To prevent this we recommend using the Vinmetrica Electrode Holder to stabilize your electrode Rinse the electrode briefly with distilled water Insert the electrode into the titration beaker so that the tip is completely submerged to just above the circulation gaps cutouts at the tip of the electrode but above the level of the stir bar approximately half an inch from the bottom of the titration beaker If you are using the Vinmetrica Electrode Holder adjust it to a similar level If you are stirring manually begin now use
38. the calculation is simply ppm Free SO 20 V i e 20 times V 1 64 mg SO2 mmol SO2 V mL N meq mL 1000 mL L 2 meq mmol SO2 S mL SC 300 Pro Kit Manual 14 Version 1 5 Measuring Total SO by Titration optional requires IN NaOH l Place 25 mL wine or must in the titration vessel See Figure 21 2 Add 10ml 1N sodium hydroxide Vinmetrica Part number SC 100 17 and mix well Let stand approximately 10 minutes 3 Using the transfer pipettes add approximately 8 mL of the Acid Reagent and 2 mL of the Reactant solution to the vessel Remember that if you are using the transfer pipettes in the kit 2 mL is the amount that fills the bulb with a vigorous squeeze so dispense four of these for the Acid Reagent 4 Proceed from step 5 in the Free SO2 procedure above The result calculated will be total SO rather than free SO in parts per million ppm Calibration of pH 1 Be sure the pH electrode is attached to the unit then select CAL mode by pressing the MODE button until the CAL LED illuminates 2 Choose a calibration set that corresponds to the range you are working in Usually for wine this will be at pH values below 4 so use the 4 7 set If you have a source of a pH 3 00 reference solution you can use this in place of pH 4 3 Rinse the electrode with DI water shake or blot off excess liquid gently and place the electrode into a small vessel like the pH 4 Reference Solution cap containing o
39. tments Using the Winemaker Magazine Sulfite Calculator Winemaker Magazine s Sulfite Calculator at http winemakermag com guide sulfite is an excellent tool for calculating how much sulfite should be added to your wine We will briefly go over the process here for some clarification First select a Preferred method of Sulfite addition we recommend using a 10 solution of Potassium metabisulfite KMBS You can prepare this solution by weighing out 10g of KMBS and dissolving it in a FINAL volume of 100 mL DI water Next choose the wine type red or white Keep the Desired Molecular SO at 0 8 mg L and enter your wine s pH value hit your keyboard s Enter button after entering the value One thing to notice is that after entering in your Desired molecular SO and your wine s pH the calculator will ask you to enter the Desired level of free SO2 The value you should enter for this field should appear in the Notes section within the following text 1 The recommended level of free SO gt for this type of wine molecular SO2 amp pH is your value mg L Then input the Current level of Free SO2 which you determined from measuring Free SO with the Vinmetrica SC 300 Finally enter the volume of wine to be corrected Choose liters or gallons we prefer liters because the answer is returned in mL The Amount of sulfite to be added should be in mL or fluid ounces of 10 sulfite solution or in grams if you use sulfite p
40. tralized by slow addition of baking soda sodium bicarbonate with stirring until effervescence ceases Technical assistance info vinmetrica com tel 760 494 0597 SC 300 Pro Kit Manual 18 Version 1 5 WARRANTIES AND LIABILITIES l The materials provided in the kit as described on pages 1 and 2 above Materials are warranted as follows The SC 300 instrument electrodes and non reagent accessories are warranted against defects in workmanship for 12 months from date of purchase The reagents are warranted to perform as described herein up until any stated expiration date or 6 months after purchase whichever is later THE WARRANTIES IN THESE TERMS AND CONDITIONS ARE IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED INCLUDING WITHOUT LIMITATION ANY WARRANTIES OF MERCHANTABILITY NONINFRINGEMENT OR FITNESS FOR A PARTICULAR PURPOSE SAID WARRANTIES BEING EXPRESSLY DISCLAIMED 2 Buyer agrees that its sole and exclusive remedy against Vinmetrica shall be limited to the repair and replacement of Materials or parts of Materials provided Vinmetrica is promptly notified in writing prior to the expiration of the warranty period specified above of any defect Vinmetrica s liability for any damages due Buyer shall be limited to the purchase price of the Materials 3 VINMETRICA S MAXIMUM LIABILITY FOR ALL DIRECT DAMAGES INCLUDING WITHOUT LIMITATION CONTRACT DAMAGES AND DAMAGES FOR INJURIES TO PERSONS OR PROPERTY WHETHER ARISING FROM VIN
41. vels you can make adjustments when needed especially before starting primary fermentation after malolactic fermentation has completed after racking or when ready to bottle To correctly adjust sulfite you need values for your current Free SO level and your wine s pH both of which can be measured with the Vinmetrica SC 300 analyzer The key parameter in protecting your wine is Molecular SO2 which for most wines should be at 0 8 ppm mg L following primary fermentation This in turn depends on the Free SO it can also be referred to as unbound SO and the pH Overall you can reach your target Molecular SO2 by measuring and adjusting your free SO levels and considering your wine s particular pH See Table 1 Table 1 Free SO concentrations necessary to attain 0 8 mg L Molecular SO at a designated pH FreeSO2 ppm 13 16 21 26 32 40 so 63 79 99 125 We recommend using a sulfite calculator for determining how much sulfite to add to your wines after taking a sulfite measurement with the SC 300 Pro Kit Winemaker Magazine s Sulfite Calculator at http winemakermag com guide sulfite can walk you through the process See Appendix B for more information on how to adjust your wine for sulfite Monitoring your wine s pH is especially important for the first few months of the wine making process Proper pH and Titratable Acidity TA levels influence mouth feel and provide wine stability During malolactic fer
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