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VISCTM User's Manual - Cole

1. 1 K Walters Rheometry Chapman and Hall London 1975 52 Theory of Operation pressure sensor array Thus the sensor can be treated as an ideal two dimensional system and the viscosity can be calcu lated from first principle equations 6 Apparent Shear Rate Yapp wh Shear Stress t SUPE a 4 Oh T Viscosity n Yapp Q flow rate w width of channel h height of channel For Newtonian fluids the above calculations are sufficient For Non Newtonian fluids the apparent shear rate is different from the true shear rate and the Weissenberg Rabinowitsch correction must be applied For more information please visit www rheosense com Principle html 53 Technical Specifications Part Number Accuracy of reading Repeatability Flow Rate pl minute 0 5 450 Temperature Range C F 18 40 64 104 Temperature Accuracy C F 0 15 0 27 Humidity Range o 90 non condensing Battery Life 100 measurements per charge Power VDC 8 Use only the supplied adaptor Pipette Volume ul 400 Dimensions L x W x H cm 14 5 X 21 6 X 7 1 5 7 X 8 5 x in 2 8 Weight kg Ibs 0 8 1 76 Waste Container Volume ml Advanced Operation Mode Available Sensor Cartridges HAot1 o1 Flow Channel Depth um 50 Shear Rate Range 1 s 6 5 5 850 Viscosity Range mPa s 0 2 100 t Only when measurement is taken with a new pipette 54 Technical Specifications 0 5 450
2. 64 Shear Stress Pa M1 4 NxtPg lt E gt 2 3 SID 10RB05100143 Sensor Serial Number P SCALE 50 3 Percent Full Scale 65 8ul R 2 1 000 Total volume ul R value M1 t4 NxtPg lt E gt 3 3 The R value is an indicator of the quality of the measurement It denotes how linear the pressure drop across the sensor is Ideally it will equal 1 000 If the R value is below 0 980 the measure ment result may not be reliable 4 System Information Entering this function brings up three screens with detailed information on the system RhcoSense uvist yro Ricokensa MISC H W CTRL_C1 0 128K F W C1A 20110120 ware version number firmware product version number hard S N H1110 00001 4 3 Version number and the serial number of the pVISC unit Screen 2 sensor element chan CH WIDTH mm 3 16 CH_DEPTH um 49 83 MAX P Pa 40000 0 S element channel depth in S I D 10RB05100143 2 3 micrometers maximum pres nel width in millimeters sen System Information 39 Menus and System Options sure of the sensor element in Pascals and the sensor ID number of the currently installed sensor cartridge Screen 3 safety limit of the SAFETY LIMIT 4078 DIAMETER mm 3 18 sensor element in UTI counts VOLUME ul 400 inner diameter of the dispos 3 3 able pipette nominal volume of the pipette 5 System Configuration This function allows certain pa rameters of the system to be
3. Main Menu screen has been entered press the MENU button at any point to go back a level 1 SET ADVANCED MEAS 2 SET SAMPLE ID Press 1 to enter the Set Ad 3 VIEW PREVIOUS MEAS _ vanced Measurement menu lt MENU gt t No 1 3 1 SET NEW PARAMETERS There are two screens in the 2 VIEW LOAD PROTOCOL Set Advanced Measurement 3 SAVE NEW PROTOCOL mMenu Press the Navigation Select No 4 2 Arrows to move between them 4 DELETE A PROTOCOL Press 1 to enter the Set New 5 LOAD FACTORY PARAM Parameters menu Select No _ 2 2 Setting Advanced Parameters 26 Operating Modes 1 RATE s AUTO There are two screens in the 2 MEAS VOL ul AUTO Set New Parameters menu 3 PRIME VOL ul AUTO Press the Navigation Arrows to Run Menu or No 1 2 Move between them To edit a menu item press the number 4 PAUSE T s 5 button corresponding to that item To change a parameter enter a number value on the Run Menu or No _ 2 2 keypad while the value is blinking then press ENTER To cancel the change press the MENU button To return to the previous menu press the MENU button To start a meas urement with the newly set parameters press the RUN STOP button The parameters are 1 Rate The units for Rate are either s inverse seconds for shear rate or pl m microliters minute for flow rate This is the rate at which the sample fluid is pumped through the sensor cartridge The available flow rate ra
4. the 3 Results screens VISC mPars 2 125 23 00 C 604 7 s 70 4 ul SCALE 50 8 Run Menu Home _ 1 3 S STRESS Pa 128 64 Shear Stress Pascals F RATE ul m 173 0 Flow Rate microliters minute SLOPE Pa mm 30 4 Pressure Slope Pa millimeter Run Menu Home _ 2 3 Automatic Mode In Detail 23 Operating Modes SID 10RC10100094 Sensor Serial Number 01 13 11 12 51 43 Time Stamp Date and Time M TIME s 8 Measurement Time seconds Run Menu Home _ 3 3 After the Measurement After the measurement has finished 3 options will be avail able 1 Press the RUN STOP button The system will take an other measurement without running the priming opera tion The pVISC will continue to take measurements as long as there is sample remaining in the pipette Once the sample has run out the pusher will automatically return to the Home position Press the MENU button The Main Menu screen is dis played Advanced parameters and functions can be se lected from here Press the HOME button The pusher will return to the Home position to enable removal loading of the pipette and the display will return to the Ready screen Press the RUN STOP button at any point to halt the pusher After the Automatic Mode Measurement 24 Operating Modes Advanced In the Advanced mode you may set all the parameters of the measurement or leave them for the system to decide This may be especially useful if a repetitive me
5. 1 13 11 12 51 43 M TIME s 8 Run Menu Home _ 3 3 Automatic Mode Overview 19 Operating Modes Automatic Mode In Detail When the pVISC is powered on using the ON OFF switch on the left side of the unit the LCD will briefly display RheoSense uVISC vX X RheoSense uVISC vX X Oo INITIALIZATION mm dd yy hh mm ss 23 00 C 400 0 ul vX X is the product version number mm dd yy is the date and hh mm ss is the time in hours minutes and seconds The box symbol is the battery charge indicator After these two Initialization screens the Ready screen will appear LOAD SAMPLE amp mmm At this point the instrument is PRESS RUN 23 00 C ready to take a measurement Auto mode Load a pipette with sample as Menu t Change mode described in the previous sec tion and mount it in the unit as shown in the Quick Start section Press the RUN STOP but ton on the keypad to the left of the LCD display The display will show STARTING MEASUREMENT STARTING MEASUREMENT PAUSING FOR RELAXATION BASELINE MEAS TIME s 1 Automatic Mode In Detail 20 Operating Modes STARTING MEASUREMENT Checking relaxation and base MOVING TO PLUNGER line measurement could take a VOL ul 400 0 few seconds The pusher then moves towards the pipette until it contacts the plunger The decreasing volume readout while the pusher is moving represents the potential volume remaining in the pipette based on the posit
6. 18 40 64 104 0 15 0 27 o 90 non condensing 100 Measurements per charge 8 Use only the supplied adaptor 400 14 5 X 21 6 x 7 1 5 7 x 8 5 x 2 8 0 8 1 76 HCo2 01 100 1 7 1 453 500 20 000 Contact Rheosense for applications outside this range 55 Quick Reference Guide To do This Take a measurement Press the RUN STOP button from e Any Ready screen p 16 e Any Results screen p 23 e After setting any parameter in the Set New Parameters screen p 27 Measure at a specific From a Ready screen press MENU 1 shear flow rate Set Advanced Meas 1 Set New Pa rameters 1 Rate Enter a new value then press ENTER RUN STOP p 27 Load a User Protocol From a Ready screen press MENU 1 Set Advanced Meas 2 View Load Protocol Up Down Arrow to change ENTER p 32
7. CE uVISC User s Manual The Revolutionary Viscometer S RHEOSENSE INC RheoSense pVISC Portable Viscometer User s Manual Foreword Rev 1 2 Thank you for your purchase of the yVISC Viscometer This instrument contains the most advanced microfluidic viscosity sensor on the market today The pVISC was designed to be intuitive and easy to use but there are a few things that should be kept in mind when operating it If you re like most people and don t like reading manuals at least glance through the Precautions and Quick Start sections before using the instrument for the first time An understanding of the basics is all you need to get accurate repeatable results right from the start Once a few measurements have been taken the rest of this manual can be used for reference and learning the ad vanced functions of the instrument 2678 Bishop Drive Suite 270 San Ramon CA 94583 Phone 925 866 3802 Fax 925 866 3804 www rheosense com info rheosense com or service rheosense com US Patent Numbers 7 290 441 and 6 892 583 The information contained in this document is believed to be correct but Rheosense Inc accepts no liability for any errors it contains and reserves the right to alter specifications without notice 10 Precautions Read these instructions Keep these instructions Heed all warnings Remove the waste container before flipping the unit over or the waste liquid will spill Never man
8. NTER Confirms a keyed in value HOME Button Sends the pusher to the home position from the Ready or Results screens to enable the removal or loading of a pipette Hardware Overview Removing Exchanging the sensor cartridge we Grasp the top of the sensor cartridge and pull up 10 Hardware Overview Removing the waste container Grasp the waste container by the protruding tab and pull out ward 11 Quick Start 1 Power the unit on with the On Off Switch on the side Load a pipette with sample by grasping the flange and slowly drawing back the plunger while the tip of the pi pette is in the sample sy 4 yy ENSE 400 ul 12 Quick Start 3 Mount the pipette in the unit by guiding the tip into the sample inlet port and firmly pushing down on the flange of the pipette until it clicks into place ki ooo Tsc AN om 4 Press the RUN STOP button on the keypad Loading the Pipette General Considerations e Whenever handling a pipette always hold it by the rec tangular flange This minimizes heat transfer to the sam ple fluid Do not hold the pipette by the plunger when filled as this may result in expelled sample or a bubble being drawn into the tip e After filling the pipette wipe the excess fluid off the out side of the pipette with lint free wipes This will help prevent lint or foreign particles from entering the sensor element and damaging it e Do not over fi
9. OCOL TO DELETE a new protocol the Protocols L View ENT Del 8 8 full screen will appear In or der to save the new protocol a currently saved protocol must first be deleted View the cur rently saved protocols by using the Up Down Navigation Ar rows Press ENTER to delete the selected protocol or press MENU to exit without deleting Saving Measurement Protocols 3i Operating Modes Retrieving and Deleting Measurement Protocols To load a previously saved protocol From the Main Menu press 1 to enter the Set Advanced Measurement menu then press 2 to get to the View Load 1 USER PROTOCOL 1 SR 334 5 PV 25 ul Protocol screen The first PT 7s MV 100 ul saved protocol will be dis t View ENT Load_1 8 Played Use the Up Down Navigation Arrows to scroll through the saved protocols Press ENTER to load the proto col shown and return to the Advanced mode Ready screen Press the MENU button to return to the Set Advanced Meas urement screen To delete a previously saved protocol From the Main Menu press 1 to enter the Set Advanced Measurement menu Press 4 1 USER PROTOCOL 1 to get to the Delete a Protocol SR 334 5 Py 25 yl Screen The first saved proto PT 7s MV 100ul c l will be displayed Use the View ENT Del_1 8 Up Down Navigation Arrows to scroll through the saved protocols Press ENTER to delete the protocol shown Press the MENU button to return to the Set Advanced Measurement m
10. X X E m a INITIALIZATION RheoSense uVISC vX X 1 The unit initializes when it eum i first turned on This second mm dd yy hh mm ss screen appears briefly as ini 23 00 C 400 0 ul tialization completes LOAD SAMPLE amp i ma 2 When this screen appears PRESS RUN 23 00 C load a pipette with sample and Auto mode insert it into the unit Menu t Change mode STARTING MEASUREMENT 3 This appears after the PAUSING FOR RELAXATION RUN STOP button is pressed TIME s 1 Automatic Mode Overview 17 Operating Modes STARTING MEASUREMENT BASELINE MEAS STARTING MEASUREMENT 4 The pusher moves to the MOVING TO PLUNGER plunger when this appears VOL ul 400 0 STARTING MEASUREMENT PLUNGER DETECTED PAUSING FOR RELAXATION TIME s 1 PRIMING 5 When this screen appears 23 00 C 55s 0 1 ul 1 sec P 23 0 0 5 the sensor is being primed with test fluid STARTING MEASUREMENT PAUSING FOR RELAXATION TIME s 1 Automatic Mode Overview 18 Operating Modes STARTING MEASUREMENT BASELINE MEAS VISC mPages 2 13 6 The viscosity measure 23 00 C 605 1 s ment begins when this screen SCALE 49 5 appears VISC mPass 2 12 23 00 C 604 7 s 7 Here the final results are 70 4 ul SCALE 50 8 displayed Run Menu Home _ 1 3 S STRESS Pa 128 64 F RATE ul m 201 3 SLOPE Pa mm 30 4 Run Menu Home _ 2 3 S N 10RC10100094 0
11. allows modification of the system time and date so the time stamp of stored meas urements is accurate To change the time or date 1 SET TIME hh mm ss 2 SET DATE mm dd yy press the number on the key pad that corresponds to that item The first number hh for time or mm for date will be Select _ gin blinking Enter 2 digits on the keypad and the next number will blink mm for time or dd for date After entering the last 2 digits press ENTER Note that time is Setting Time and Date 41 Menus and System Options only available in the 24 hour format 7 Diagnostics When the system boots up it runs a self MEMS OK diagnostic routine This func SENSOR BD OK tion shows the results of the EEPROM OK diagnostics and in the event of BATTERY OK a system malfunction or failure can help in troubleshooting the problem 8 Maintenance This screen shows information on the us WASTE VOL ml 7 0 of the en The camer MEAS COUNT 176 keeps track of the number o V_BAT V 8 0 measurements performed and 7 the total volume of fluid dis pensed during those measure ments When the Waste Volume counter reaches 40 ml the system will show an alert that the waste container needs to be emptied 40 ml corresponds to 100 measure ments of 400 ul each Item 3 is the current voltage level of the rechargeable battery Diagnostics Maintenance 42 Warning and Error Messages The following Warning Messages
12. alue is reached and any previ ously measured sample has been moved through the sensor priming stops When replacing higher viscosity fluid with lower viscosity fluid the system will generally require a larger priming volume If 50 of full scale cannot be reached even at the maximum pumping rate of the system priming will be stopped after 200 pl have been pumped or the viscosity has stabilized After priming the system waits for the stress created by the moving fluid to dissipate before the baseline is measured For higher viscosity fluids this could take 10 20 seconds STARTING MEASUREMENT STARTING MEASUREMENT PAUSING FOR RELAXATION BASELINE MEAS TIME s 1 Automatic Mode In Detail 22 Operating Modes Once the measurement starts the following information is displayed Viscosity mPa s temperature VISC mPaes 2 132 23 00 C 605 1 s C pumping rate s or ul SCALE 49 5 min cumulative dispensed volume ul pressure repre sented as a percentage of full scale and the measurement progress bar All the values ex cept dispensed volume are instantaneous readings The measurement stops automatically when the reading has stabilized The data displayed on the Results screen are all average values except the volume which is the cumulative amount dispensed including priming To view other pa rameters of the measurement use the Up Down Navigation Arrows on the keypad to move among
13. any of the Ready screens 1 SET ADVANCED MEAS 2 SET SAMPLE ID 3 VIEW PREVIOUS MEAS lt MENU gt t No 1 3 4 SYS INFO 5 SYS CONFIG 6 SET TIME amp DATE lt MENU gt t4 No 2 3 7 DIAGNOSTICS 8 MAINTENANCE lt MENU gt t No 3 3 Move among the three screens by pressing the Up Down Navigation Arrows To select a menu item press the number on the keypad that corre sponds to that item To move back a level in any of the menus press the MENU but ton Each item is detailed be low 1 Set Advanced Measurement See the detailed description in section 7 2 Set Sample ID Entering this function brings up the screen seen at the top of page 37 The ID must be set before a measurement is taken in order for it to appear in the data log Main Menu 36 Menus and System Options SET SAMPLE ID The current sample ID is H1 shown To edit the sample ID press the Up Arrow To exit Edit 4 Return _ press the Down Arrow or MENU button When the edit sample function SET SAMPLE ID is active the cursor will blink Use the numeric keypad to t Del HOME Symbol enter alpha numeric charac ters Pressing a number button in quick succession will scroll through the available num ber and letters for that button Wait 1 5 seconds for the cursor to advance Button functions are Up Navigation Arrow Delete Down Navigation Arrow Space MENU button Cancel changes and exit edit
14. asurement needs to be done at a specific shear flow rate or the same amount of sample needs to be used for each measurement In addition measuring a given sample at multiple shear flow rates may help you determine if a sample is Non Newtonian If a fluid is Newtonian has the same viscosity at all shear rates gener ally Auto mode is all that is needed If a testing protocol re quires a specific shear flow rate Advanced mode must be used since the shear flow rate is always determined by the system in Auto mode Two other parameters in Advanced mode may be left for the system to decide or specified by the user Measurement Volume and Priming Volume These two parameters are always handled by the system in Auto mode The Advanced mode parameters are described fully in the Setting Advanced Parameters section In general customiz ing the parameters to a specific measurement task can make routine measurement processes more efficient The Advanced mode is not available on all 4VISC models Advanced Operating Mode 25 Operating Modes The Advanced mode Ready screen shows the currently set shear flow rate The factory default setting is Auto mode the system will determine the rate as it does in the Automatic Measurement mode To change the system Rate units shear s or flow ul m see Section 8 Menus and System Options Setting Advanced Parameters From the Ready screen press the MENU button to enter the Main Menu screen Once the
15. e Results screens will be displayed Depending on the sensor cartridge in use the percent full scale SCALE parameter may be very low This is because cleaning is most effective when the solvent is pumped fairly slowly through the microfluidic channel which leads to low full scale pressure readings Because of this the viscosity value of the cleaning fluid after a cleaning run may not be entirely accurate After cleaning if there are no more measurements to be made leave the empty solvent pipette in the pVISC unit If removing the sensor cartridge store the cartridge with the stopper firmly pressed into the inlet port Cleaning Mode 34 Menus and System Options The pVISC has the following menu item structure Main Menu 1 Set Advanced Meas 2 Set Sample ID 3 View Previous Meas 4 Sys Info 5 Sys Config 6 Set Time amp Date 7 Diagnostics 8 Maintenance gt Set Advanced Meas 1 Set New Parameters gt 2 View Load Protocol 3 Save New Protocol 4 Delete a Protocol 5 Load Factory Param Set New Parameters 1 Rate 2 Measure Volume 3 Priming Volume 4 Pause Time System Config 1 Rate Type 2 Button Sound 3 Auto Sleep Set Time amp Date 1 Set Time 2 Set Date 35 Menu Tree Menus and System Options The Main Menu consists of three screens The Main Menu is accessed by pressing the MENU button while in
16. e priming step again Out of Sample The pusher reached the end of its travel Please wait before the measurement finished This clears when the pusher returns to the home position Warnings 44 Warning and Error Messages Warning Message Description Action Required Priming Time Out The system was unable to achieve a Measure Again stable value during the priming opera tion This can happen if the previously measured sample had a much different viscosity than the current sample and residue is left Repeat the measurement again or perform a cleaning cycle with an appropriate solvent No Pipette The system was told to take a measure Please wait ment without a pipette loaded This clears when the pusher returns to the home position Unstable Tempera The system is measuring an unstable ture ambient temperature which could af fect measurement quality Press ENTER dT 0 5 C min ASASI to continue with the measurement or the MENU button to abort Low Battery Level The battery requires recharging Use Please Recharge the supplied power adapter to recharge it Warnings 45 Warning and Error Messages Warning Message Description Action Required No Data Exists This appears when the user tries to view previous measurements but none have been taken Sleep Mode in30 The system has been idle and will enter sec To Keep Op sleep mode in 30 seconds Press the eration Press Menu MENU bu
17. enu Retrieving and Deleting Measurement Protocols 32 Operating Modes Cleaning In general samples may be tested consecutively without cleaning the sensor cartridge in between However the sen sor cartridge must be cleaned if The pVISC will not be used for a day or longer The sensor cartridge will be removed from the unit and stored for a day or longer The sensor cartridge is going to be removed from the unit for an hour or longer and has been used with a sam ple comprised of particulate matter and high volatility solvent such as ink The sample fluid about to be tested is immiscible with the previous sample i e testing an aqueous solution after testing an oil based calibration standard You are unsure whether you should run a cleaning cycle Cleaning is fast easy and will protect your instrument from damage To clean the sensor cartridge fill a new pipette with a solvent that is miscible with the sample s used a small mixture of the sample and solvent appears homogeneous and not cloudy Mount the pipette in the yVISC and from a Ready Cleaning Mode 33 Operating Modes screen use the Up Down Navigation Arrows to move to the Cleaning mode Ready screen Press the RUN STOP button to begin the cleaning procedure The system will dispense the entire contents of the pipette at 100 l m so for a full pipette the cleaning cycle will take about 4 minutes At the end of the cycle the standard thre
18. factory default is Auto mode Setting Advanced Parameters 28 Operating Modes 4 Pause Time seconds After priming the system must pause to wait for the stress created by the moving fluid to dissipate before an accurate baseline can be measured The available pause times are 0 36 000 seconds The factory default is 5 seconds Note that the pause time function may also be used as a timer Saving Measurement Protocols After the Advanced mode parameters have been set they can be saved as a user protocol for future use Up to 8 different protocols may be saved at a time To save a user protocol from the Main Menu press 1 to enter the Set Advanced Meas urement menu then press 3 to enter the Save New Protocol function Ifa previously created protocol is loaded its ID will ID EMPTY be shown above the protocol SR 334 5 PV 25 ul values If no protocol is PT 7s MV 100 ul loaded EMPTY will be dis t Edit ID 4 GoNext _ played in the ID field To change the protocol values press the MENU button to return to the Set Advanced Meas urement menu and follow the instructions in the previous section To edit or assign a protocol ID for the current set of parameters press the Up Navigation Arrow Saving Measurement Protocols 29 Operating Modes ID USER PROTOCOL 1 When the Edit ID screen is SR 334 5 PV 25 il active the cursor will blink PT 7s MV 100ul Use the numeric keypad to t Del HOME Symbo
19. ical measurements always use a new pipette 49 Calibration and Maintenance Your PVISC Viscometer has been calibrated with NIST trace able standards The calibration of the unit is valid for 1 year from the date of purchase Each sensor cartridge comes with its own calibration certificate valid for 6 months from the date of calibration For re calibration please contact Rheo sense at service rheosense com The following maintenance schedule is recommended Daily Wipe excess sample away from the inlet of the sensor cartridge with lint free wipes dampened with cleaning agent Dip a lint free swab in cleaning agent and wipe the interior walls of the sensor cartridge inlet Use a cleaning agent that is compatible with the sample s that was were run See the list on page 51 for recom mended cleaning agents Run 1 2 cleaning cycles with an appropriate solvent when done using the instrument for the day 2 3 if measuring inks Turn off the power switch and leave the empty solvent pipette in the yWISC unit until it will be used again If removing the sensor cartridge store the cartridge with the stopper firmly pressed into the inlet port Monthly Wipe residue away from the drain hole near the exit tube of the sensor cartridge using lint free wipes dampened with an appropriate solvent 50 Calibration and Maintenance e As Needed Empty the waste container Charge the bat tery using only the supplied power adapter Wi
20. ion of the pusher Once the plunger has been reached the display will show STARTING MEASUREMENT The pause for relaxation could PLUNGER DETECTED take a few seconds or longer PAUSING FOR RELAXATION depending on the viscosity of TIME s 1 the fluid Priming now commences PRIMING 23 00 C 55s Priming is the act of filling the 0 1 ul Jeet microfluidic channel with the P 23 0 0 5 test fluid Priming is always performed at the start of a measurement when the pusher is not in contact with the pi pette plunger If the microfluidic channel is dry it must be filled with sample before an accurate baseline can be read If the channel is wet from a previous sample the previous fluid must be completely replaced Even trace amounts of a previ ous sample could cause significant error in the measurement Automatic Mode In Detail 21 Operating Modes Priming volumes typically range from 10 to 200 ul On the Priming screen 5 pieces of data are displayed the current temperature in degrees Celsius C the current pumping rate in inverse seconds s or microliters per minute l min total pumped volume in microliters ul elapsed time in sec onds and the current pressure in Pascals Pa Also displayed with the pressure is a number which represents the percent of full scale pressure of the sensor The yVISC will attempt to pump the fluid at a rate that results in a pressure reading of 50 of full scale Once this v
21. l enter alpha numeric charac ters Pressing a number button in quick succession will scroll through the available number and letters for that button Wait 1 5 seconds for the cursor to advance Here is a list of button functions Up Navigation Arrow Delete Down Navigation Arrow Space MENU button Cancel changes and exit edit mode ENTER button Confirm new protocol ID Number buttons Type numbers and letters HOME button Scrolls through 8 symbols _ The protocol values displayed are SR or FR Shear Rate in inverse seconds or Flow Rate in microliters per minute depending on the system setting PV Priming Volume in microliters PT Pause Time in seconds MV Measurement Volume in microliters Saving Measurement Protocols 30 Operating Modes ID USER PROTOCOL 1 After the protocol ID has been SR 334 5 PV 25 ul input press the ENTER button PT 7s MV 100ul Lhe Edit ID screen will be ex t Edit ID 4 GoNext ited Press the Down Arrow to go to the Save Confirmation 1 USER PROTOCOL 1 screen Press the ENTER but SR 334 5 PV 25 ul PT 7s MV 100 ul ENT Save MENU Ret _ ton to commit the ID and pro tocol values to memory Press ing the MENU button will re turn the system to the Set Advanced Measurement menu Once saved the Advanced mode Ready screen will be shown ALL USER PROTOCOL If all User Protocol Slots are SLOTS FULL CHOOSE filled when attempting to save PROT
22. ll the pipette as this may prevent the pi pette from fitting into the yVISC unit Minimizing Bubbles The pVISC disposable pipette has been designed with a very small dead volume but a small bubble about 1 1 5 pl in vol ume will always be trapped when drawing sample into a dry pipette If the bubble is dispensed into the instrument erro neous values may result Always try to load the pipette so there are no bubbles in it To remove the small bubble that results when first drawing sample use one of the following two techniques General Considerations Minimizing Bubbles 14 Loading the Pipette A This technique may be employed for samples of all vis cosities 1 Insert the pipette into the sample and draw a small amount of liquid into the pipette Only draw in enough liquid to see the formation of the bubble 2 Fully expel the liquid into a waste container 3 Insert the pipette back into the sample and slowly draw the desired amount of sample into the pipette B This technique will only work for lower viscosity samples 1 Insert the pipette tip into the sample and draw the desired amount of sample into the pipette 2 Hold the pipette vertically by the rectangular flange so the tip is pointing at the ceiling Flick the side of the pipette until the bubble rises to the tip 3 Push the plunger slightly until the bubble is expelled from the tip Minimizing Bubbles 15 Operating Modes There are three ope
23. may occur during operation of the pVISC A brief description and tips for correcting the problem are given In most cases press the MENU button to clear the warning A typical lt WARNING gt Insufficient Meas Measure more Warning screen looks like this PRESS lt MENU gt Warning Message Description Action Required Insufficient Meas Too little sample was available to get an Measure More accurate reading This could happen when the measurement is stopped pre maturely by the user or if there was not enough sample remaining in the pipette when the measurement started Let the measurement complete on its own or Meas Not Good The system was unable to take a stable Measure Again measurement most likely due to a bub ble in the flow channel Warnings 43 Warning and Error Messages Warning Message Description Action Required Over Full Scale This appears in Advanced Mode when Use Auto Mode the shear flow rate is too high for the pressure range of the sensor Reduce the shear flow rate or use Auto mode to find an appropriate shear flow rate Low Full Scale The pressure of the leading flow sensor Change Flow did not go above 4 of full scale during Rate the measurement Increase the flow or shear rate to ensure accurate readings Low Pressure This appears during priming if there is a bubble or the flow channel has not been entirely wetted with the sample The system will attempt th
24. mode ENTER button Confirm new sample ID Number buttons Enter numbers and letters HOME button Scrolls through 8 symbols _ Setting Sample ID 37 Menus and System Options 3 View Previous Measurements Entering this function brings up the data log display The most recent measure ment record is displayed first A total of 20 records are held in memory Once the 20 slots labeled Mo Mig are filled new measurements overwrite the old records in order of date written with the oldest record being over written by the newest measurement The measurement record slots are static so when one slot is filled a new measurement will overwrite the next slot i e after Mig is filled Mo will be overwritten Pressing the ENTER button will allow you to scroll through the 3 screens in each record The MENU button will return you to the Main Menu and the Up Down Navigation Arrows allow you to switch from one meas urement record to another Each measurement record contains the following three screens ID 1 Sample ID 01 20 11 12 01 09 Time Stamp Date and Time 23 10 C 2 235 mPaes Temp C Viscosity mPa s M1 t NxtPg lt E gt 1 3 Measurement Number The most recent measurement record is denoted by an asterisk next to the measurement number Viewing Previous Measurements 38 Menus and System Options Flow Rate ul m F RATE ul m 275 5 S RATE s 539 60 Shear Rate s S STRESS Pa 128
25. modified The following options are available 1 RATE SHEAR 7 Rate The system may be set to 2 BUTTON SOUND ON 3 AUTO SLEEP ON ters per minute or shear rate Select 4 4 in inverse seconds To use either flow rate in microli change the units press 1 on the keypad use the Navigation Arrows to select the desired units then press ENTER Factory default is shear rate Note that for a given shear rate the flow rate will not always be the same for different sensor cartridges and vice versa For a given flow rate the shear rate depends on the depth of the microfluidic flow channel in the sen sor element which can vary between sensor cartridges Button Sound Buttons on the front panel will beep System Configuration 40 Menus and System Options when pressed if this feature is turned on To change the setting press 2 on the keypad use the Up Down Naviga tion Arrows to select on or off then press ENTER Fac tory default is on Automatic Sleep This function will allow the system to enter sleep mode automatically when there has been no activity for 10 minutes Sleep mode greatly reduces bat tery consumption but does not eliminate it entirely Turn the main power switch off if the system will not be used for several hours or more To change the setting press 3 on the keypad use the Navigation Arrows to se lect on or off then press Enter Factory default is on 6 Set Time amp Date This function
26. netseectesaseseeneveaie ence ee igs eevwesncsendeueeednvaess EEEN EE 33 Menus and System Options cccccesseeesteeeeseeeeeeeeees 35 Warning and Error Messages cssccesseeseeseeseeeeeees 43 Tips For Best Results ccssscccsssccsssescsssscssnnscessenes 49 Calibration and Maintenance cccccccccssseeeeseeeeeseeees 50 Theory of Operation cccsccsssccssscsssesssessseesenssseeees 52 Technical Specifications ccccccssecssteseseeceeesseeesseeees 54 Quick Reference Guide cccccccssscecsseceesseeeeeseeeesseeees 56 Hardware Overview sensor pipette cartridge pipette retaining clip sample outlet adapter tube display keypad jack Hardware Overview pusher sensor Standby cartridge button lid pusher trough ASB waste ON OFF connector container switch port Hardware Overview Standby Toggles the unit in and out of sleep mode when the main power is on RUN STOP Starts a measurement from the Ready or Results screens or stops a measurement at any point in the cycle This will also halt the pusher when it is moving to the home position except when the unit is first powered on MENU Return Selects a menu or navigates backwards Hardware Overview Navigation Arrows Moves between multiple pages of data or through menu items Data Entry Buttons Use these to enter numeric parameters or alpha numeric data labels E
27. nge is 0 5 450 l m The available shear rate will de pend on the specific sensor cartridge used Factory de fault is Auto mode the system will determine the rate as it does in the Automatic Measurement mode See sec tion 13 Technical Specifications for the shear rate ranges of available sensor cartridges Setting Advanced Parameters 27 Operating Modes 2 Measurement Volume ul The available measurement volume range is 5 400 pl Auto mode may also be se lected in which case the system will determine when to end the measurement based on the stability of the viscos ity reading The factory default is Auto mode 3 Priming Volume pl Priming is the act of filling the mi crofluidic channel with the test fluid Priming is always performed at the start of a measurement when the pusher is not in contact with the pipette plunger If the microfluidic channel is dry it must be filled with sample before an accurate baseline can be read If the channel is wet from a previous sample the previous fluid must be completely replaced Even trace amounts of a previous sample could significantly skew the measurement results The available priming volume range is 1 200 pl Auto mode may also be selected in which case the system will end the priming once it determines all the previous sam ple fluid has been replaced When replacing higher viscosity fluid with lower viscosity fluid the system will generally require a larger priming volume The
28. pe down the keypad and housing using a soft cloth dampened with water and a mild detergent The classes of chemicals in the table below are compatible with the pVISC Viscometer for measuring or cleaning The wetted parts of the fluid path include Polypropylene HDPE PEEK Perlast Borosilicate glass silicon and gold When using solvents always work in a well ventilated area or fume hood For information on chemicals not listed here please contact Rheosense t Results may vary depending on usage Aquet Detergent 1 and Phenols avoid contact with water the front panel Aliphatic Alchohols Amides Benzenes aromatic Esters Ethers Hydrocarbons Chlorinated Hydrocarbons Ketones 51 Theory of Operation The pVISC Viscometer uses VROC Viscometer Rheometer On a Chip microfluidic sensor technology The VROC sensor measures viscosity from the pressure drop of a test liquid as it flows through a rectangular slit This is a well known scientific principle and is described in Rheology textbooks The VROC sensor consists of a rectangular glass flow channel and a monolithic Silicon pressure sensor array as depicted in the diagram below not to scale Pressure Sensors The width of the flow channel is much greater than the depth so the flow effects from the edges of the channel are negligi ble The geometry of the sensor also ensures a fully developed laminar flow and a linear pressure drop along the
29. rating modes available on the pVISC Automatic Advanced and Cleaning Automatic mode is the One Touch measurement mode in which the system decides all parameters of the measurement For Newtonian fluids fluids that have the same viscosity at all shear rates Auto matic mode is generally all that is needed to get accurate re peatable data Advanced mode gives the user control over all the parameters of the measurement This can be beneficial when a test at a specific shear or flow rate is required or a certain volume must be tested each time Cleaning mode simplifies the task of cleaning the microfluidic flow channel in the sensor with optimized solvent flow rates LOAD SAMPLE amp EEE PRESS RUN 23 00 C Auto mode Menu t Change mode From the Ready screen switch between the 3 operating modes by pressing the Up Down Navigation Arrows From any of these screens press the LOAD SAMPLE amp EEE RUN STOP button to start a PRESS RUN 23 00 C measurement using any of Advanced 100 0 s these modes The Main Menu Menu t Change mode screen can also be accessed LOAD SAMPLE amp Ezi from any of the operating PRESS RUN 23 00 C modes Ready screen by press ing the MENU button Cleaning mode Menu t Change mode Operating Modes Operating Modes Automatic Mode Overview The diagrams below show the screens that will appear as the LVISC performs an automatic measurement RheoSense uVISC v
30. tton to abort Waste Bottle Full The internal flow counter has deter Check Empty mined that 40 ml of sample have been Bottle pumped into the waste bottle since the last time the counter was cleared Press ENTER to reset the counter or the MENU button to ignore the warning Warnings 46 Warning and Error Messages When the system encounters a situation that prevents it from operating the following Error Messages may occur Try to clear the error by power cycling the unit using the ON OFF switch Contact Rheosense lt System Error gt Customer Support if the prob NO SENSOR BOARD lem persists A typical System Error screen looks like this Description Action Required No Sensor Board The system was powered on without a sensor cartridge inserted or the sensor cartridge was removed while the system was on Insert a sensor cartridge to continue Wrong Tempera The internal temperature sensor has ture Check PT1K malfunctioned or failed Contact Rheo sense for assistance MEMS Error The system has experienced an over pressure event that could have perma nently damaged the sensor element Reduce the shear flow rate if possible System Errors 47 Warning and Error Messages Description Action Required Out Of Range Use The fluid being tested is too viscous for Higher Range Car the current sensor cartridge Switch to tridge a cartridge that has a higher viscosity range Empt
31. ually depress a pipette plunger once a full pipette has been mounted into the unit as permanent damage to the sensor may result Do not allow particles larger than 5 of the sensor chan nel depth in the sample see the System Information menu for the sensor channel depth Use only the supplied power adapter to charge the unit Use only Rheosense pVISC Pipette tips in the unit accuracy is only guaranteed with a new pipette for each measurement Be careful not to spill liquid into the pusher trough open ing or into the exposed sensor cartridge slot Always perform a cleaning cycle with an appropriate cleaning solution after measuring sample fluids that leave residues behind as they evaporate 11 12 13 14 15 16 Precautions Use only lint free wipes to clean excess sample fluid from the tip of the pipette before mounting in the unit available through Rheosense Use only lint free swabs to clean the inlet port of the sensor cartridge available through Rheosense Always replace the rubber stopper in the sensor cartridge inlet port when the cartridge is not in use and there is no pipette in place Keep the original packaging material in case the unit should ever need to be shipped Do not attempt to open a sensor cartridge Doing so will void the calibration and warranty and may cause perma nent damage to the sensor Contact only qualified Rheosense personnel for servicing Servicing is req
32. uired when the viscometer fails to operate normally or has been damaged in any way including but not limited to liquids having been spilled into the vis cometer exposure to rain or condensation or the unit having been dropped ig ot ae 10 1l 12 13 14 Table of Contents Foreword Meee ane eee eee te ere Tene tna eee 2 Pieca aa NE 3 Table of Contents 5 Hardware OVEIVICW ccccccesssssccccecessseccececessseeeceseees 6 ick Sia ersa 12 Loading the Pipette sa secsiswasceassscbanetonncanderanateusecvenseesscexendes 14 General Considerations cccccccessseceesssceceesseeccessceeeeseeeees 14 Minimizing Bubbles cscccsscsssssssssssessssssssssrssseseseceaseees 14 perading Modes amp cissusscassccensscacecevendeahdeaiarencoavecddaueneen 16 PV EC sec nese rions ar sae e Ee oE EEE ENEE EEEE 17 Automatic Mode Overview ccccssccssssccesssecessssceessssecssssecssaaecssees 17 Automatic Mode In Detail cceceeseesessscesseeseceeeceeceseesaeenseenaes 20 After the MCAS PE NIE T Cy ciscsevesesstsdoarencaseceerascardeuntecevetsiomediedsnetieess 24 Advanced carcsscscantey oa aseecantys oes satab ssa naasesensnicasasinannaneeo aaa eRes 25 Setting Advanced Parameters ssssessssssnsssseresssescesessnsenns 26 Saving Measurement Protocols ccecesscssecseeeseeeecseeeeeeseeeeeseeaeens 29 Retrieving and Deleting Measurement Protocols cee 32 Cl aniNp vacate vp sacti
33. y Invalid The memory of the sensor cartridge has EEPROM malfunctioned or failed Contact Rheo sense for assistance Pump Stalled The pump mechanism has malfunc Check Motor tioned or failed Contact Rheosense for Switch assistance Inter CPU Comm The system electronics have malfunc tioned or failed Contact Rheosense for assistance System Errors 48 Tips For Best Results Be aware of possible temperature differences between samples and the pVISC unit If the samples and instru ment were stored in different places prior to testing let them sit together with the unit on at the same location for 20 minutes or so before taking a measurement In some cases a 1 C difference in temperature can lead to an error of 5 or greater When measuring several samples of different viscosities start with the lower viscosities and move to the higher ones Each new sample will require less priming volume saving time and sample If repeated measurements of one sample shows a gradual increase or decrease in viscosity the priming volume may not have been sufficient Repeat the measurement until the reading is stable then note the total volume dis pensed until that point for future reference To conserve sample volume when measuring consecutive samples that have a difference of more than 50 in vis cosity run a cleaning cycle in between the two measure ments This will greatly reduce the priming volume needed For crit

VISCTM User's Manual - Cole

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