AFC 202D - MHz Electronics, Inc
Contents
1. Part Number Control and Power Supply Kit for QUALIFLOW Digital MFC s all series When connecting individually a Digital MFC to a computer use this interface kit which includes Q 2001733 12 e Connector conversion adapter P N q 2001733 06 e Power supply assy 120 230 VAC 15VDC P N Q2001733 14 e Power cord from power supply to MFC length 1 meter P N Q2001733 13 e RS232C cord from MFC to computer length 2 meters P N O2001733 11 Connecting cord for Analog AFC50 AFM55 or digital MFC s all series 2990924Q e D Sub 15 pin female connector MFC side wires ready to weld at the other end e Length 5 meters 2 4 CHECKS BEFORE STARTING UP Before operating the mass flow controller the following checks should be completed Check that tubing is leak proof 2 Check the process sequence and proper function of all other gas components involved 3 Check the voltage of command signals and power supply to the mass flow controller 4 Check that the appropriate gas type is being supplied at the rated pressure 5 Allow the mass flow controller to warm up for 20 minutes then check the zero level output 6 Use dry inert gas for test runs 7 Prior to using the mass flow controller for extremely corrosive gases purge with a dry inert gas for one hour 2 5 DIGITAL CARD 2 5 0 INTRODUCTION QUALIFLOW has designed and developed a digital card for its Mass Flow Controllers MFC that take advantages of the2. 3 1 0 DISASSEMBLY PROCEDURE 0 Remove any mounting plate that may be under the mass flow 1 Unscrew in and outlet fittings 7 and 8 with a 1 wrench 2 Unscrew 14 and remove the cover 19 3 Remove the sensor screws 15 with a 2 5mm hex screw driver after having the lead wires unsoldered from the p c board Handle the sensor 2 with care al Remove the screw 33 in the bottom of the valve Unsolder the magnet actuator wire from the pc board then remove the 4 screws which hold the magnet to valve body Then carefully lift the magnet Do not turn the mass flow controller now 6 Carefully remove the top housing 24 with the bellows and plunger assembly from the valve housing 23 Then carefully unscrew the lower bellow 7 Remove the 4 screws 9 in the top of the top housing 24 which hold the top ring assy 29 Then remove the bushing 32 AFC 202 D User s Manual 17 D 10 018 V04 Note If o rings are dirty cut or cracked they have to be exchanged with appropriate new clean ones 3 1 1 ASSEMBLY PROCEDURE First mount sensor inlet and outlet fittings Caution The sensor capillary sometimes extends beyond the seals o rings When positioned on the base without verifying that capillary ends fit in the holes in the base the capillary can be bend or damaged Therefore center the sensor by means of the mounting screws hold it up and then fasten the screws Normally open valve 1 Check the quality of the contact between 3 8 b
3. CALIBRATION FEATURES retara iiith a a dies 7 SECHON 2 INSTALLATION 0 a 8 205 INTRODUCTION ce o GY o GG o CF E 8 Za UNPACKING io 8 22 MECHANICAL INSTALLATION e inea crap yR CNAU NY iii 8 23 ELECTRICAL INSTALLATION pean atiii e e A FOR GYD SR aiii 10 24 CHECKS BEFORE STARTING UP i GG GU Fd GYN NA Rd 12 2 DG DR O aia 12 2 9 COMMUNICATION MODES aree A eee Bane 16 SECTION 3 MAINTENANCE oo 5532 Avi ici id ENG dnn dd HEN gd 17 BD GENERA Lata 17 3 1 DISASSEMBLY AND ASSEMBLY PROCEDURES occocococcccononncnnocanonnnonnnnanananinanonos 17 3 2 SENSOR CLEANING AND REPLACEMENT oocccccococconocinoninnnnocanoninonnanancnncnnocanecanonos 20 3 3 VALVE CLEANING AND REPLACEMENT eiii Ge TNG WY i YFC o do 20 SECTION 4 TROUBLESHOOTIN Gortari ai 21 40 INIMAL CHECK A A tias 21 Ax SYMPTOM SS uos GRAND A WG A AAA FY SOF 21 SECTION 5 WARRANTY AND SERVICES ssssccscsssociesoncoscessestecsessstscssvsncbesousessceoseoseasens 23 20 PRODUCT WARRANTY am A y Y YD GY FF FFR 2 3 1 SERVICES a 24 APPENDIX A GAS PROCESS NUMBER i c cc s0ssssashossessedasenissteed sesenddevers eoseeacadansendseosens 25 APPENDIX B EXPLODED VIEW OF THE AFC 202D ooooonoccnncccnoccconncconcnannnnnncconccnncnnnnnos 26 APPENDIX C GENERAL MFC PRINCIPLES 00 toni ss Gide aes ees 28 AFC 202 D User s Manual 4 D 10 018 V04 SECTION 1 INTRODUCTION 1 0 AFC 202 D DIGITAL MASS FLOW CONTROLLER The QUALIFLOW Digital Mass Flow Controller AFC202 D offers the highest degree of accuracy
4. by the software Problem 2 Zero reading cannot be adjusted by autozero Possible cause Action Defective sensor Check that sensor voltage between red and orange wires is equal to the voltage between red and blue wires Both must be 4 to 6 volts Contact QUALIFLOW for advice If defective the controller may need replacing Problem 3 Valve will not close Possible cause Action 1 Check the Mfc is properly connected on the gas line Disconnect the MFC after following the procedure 2 Set point is not zero Check set point voltage on PC board pin 9 3 Incorrect solder pad connections See the strap configuration 4 The Mfc is in digital mode and you use it with a set point voltage Change the control mode by the software 5 The parameters min valve for a NC is too high The parameters max valve for a No is too low Increase or decrease one of this parameter by the software 6 Incorrect actuator voltage Voltage across actuator wires must be between OV and 30V 7 Incorrect nozzle adjustment Remove mass flow controller and readjust nozzle 8 Plunger stuck Remove controller and clean up AFC 202 D User s Manual 21 D 10 018 V04 Problem 4 Controller will not open to full scale flow Possible cause Action 1 Check the Mfc is connected in the good way on the gas line Disconnect the MFC after following the
5. which brings a great improvement in process with mixed gases AFC 202 D User s Manual 13 D 10 018 V04 Flow F S 4 100 50 A Setpoint R O New digital MFC RO Analog MFC Time s 4 6 8 10 12 2 5 3 RAMPING The ramping function increases linearly the set point in order to give a progressive raise in the flow It could be used to keep stoechiometric values during transient response of a process The increase of the set point by unit time is chosen by the user see software manual F S setpoint readout Time s 2 5 4 SOFT START The soft start function closes the valve if the set point is lower than 1 F S For a new set point greater than 196F S the regulation starts after a delay that is chosen by the user This way you can avoid big overshoots caused by pressure drop when starting a process F S 1 Time s AFC 202 D User s Manual 14 D 10 018 V04 2 5 6 IN SITU CALIBRATION The calibration can be automatically made by calibration devices with a serial communication The calibration is made with six points without potentiometers The QUALIFLOW software allows to calibrate the MFC from the Molblox device Caltechnics 2 5 7 AUTO ZERO The function AUTO ZERO corrects the drift of the MFC It can be done automatically or by the user The correction can not exceed 0 5 sensor response without autozero correction with autozer
6. 018 V04 The bypass principles are based on the laminar flow theory When flow is laminar the flow is proportional to the differential pressure between inlet and outlet of the tube F TT R a p NR up down p Volumic mass of the gas n Viscosity of the gas I length of the tube R radius of the tube So when a sensor tube radius Rs length Is and a bypass tube are in parallel radius Rb length Ib the flow in the sensor tube is proportional to the flow in the bypass _ R ls AE RED a However this is true only if the flow is laminar so if the tube are small enough This is way bypass are made by several thin tube instead of only one tube It is important to notice that a mass flow meter or controller measure the flow thru the sensor which is not the total flow but only one part of the flow split by the bypass according to last equation In this eguation radius of the sensor tube and bypass tube is at power 4 Conseguently any deposition in one of the tube changing the diameter will change the accuracy of the measurement Also because of the need to have a laminar flow bypass tube and sensor tube may have clogging This why mass flow meter and controller must be used with clean filtered gases CONTROL PRINCIPLES The electronic compares the amplified mass flow rate value measured by the sensor to the desired set point This comparison generates an error signal that feeds the regulating valve The difference is use
7. 202 D User s Manual 10 D 10 018 V04 AFC 202 analog QUALIFLOW Mass Flow Controller A card edge adapters coupled with a RS232 cable is available The card edge connection is widespread in the industry e 1 Case GND 9 Setpoint elsa 10 Power Com RHOD e 3 Readout 11 Signal Com 4 415 VDC 12 Test Softstart e 5 Zero test 13 Zero command e 645VDC 14 45VDC oe Ei 15 Not used En AN o 8 Extra output Figure 2 4 Adapters pin arrangement compatible with QUALIFLOW s analog AFC 202 RS232C D Sub 9 pin RS232C D Sub 9 pin D Sub 15 pin Female d Card edga MA 20 pin D Sub 15 pin Female D Sub 15 pin Female D Sub 15 pin D Sub 15 pin Female Female Connectors Conversion Adapters GUALIFLOW MFC Connector Replaced MFC Connector Model Part Number Analog AFC50 AFM D Sub 15 Main MFC s Card edge 1 Q201733 01 55 pin Digital All Series D Sub 15 Main MFC s Card edge 1 Q201733 07 pin 2 Q201733 08 Digital All Series D Sub 15 Analog AFC50 AFM D Sub15 3 Q201733 09 pin 55 pin 4 Q201733 10 Digital All Series D Sub 15 Main MFC s D Sub 15 4 Q201733 06 pin pin 0 5V to 4 20mA Conversion Adapters MFC Type Model Part Number QUALIFLOW Analog AFC50 AFM55 3 Q201733 05 QUALIFLOW Digital and Main MFC s with D Sub 15 pin connector 3 Q201733 15 AFC 202 D User s Manual 11 D 10 018 V04 Other Accessories
8. in relation to the process seguencing As far as the process parameters will allow this it is recommended that you install an in line filter upstream to the controller in order to prevent from contamination The AFC202 D can be mounted in any position The atmosphere should be clean and dry The mounting should be free from shock or vibration Mounting dimensions are shown in figure 2 1 Prior to installation ensure that all the piping is thoroughly cleaned and dried Do not remove the protective end caps until you are ready to install the controller AFC 202 D User s Manual 8 D 10 018 V04 15 pin D CE AFC 202D MASS FLOW CONTROLLER http Awww qualifow com Pp 182 E 4 Thotes M5 7 M5 Figure 2 1 Dimensions mm 2 2 1 INSTALLATION WARNING Toxic corrosive or explosive gases must be handled with extreme care After installing the mass flow controller the system should be thoroughly checked to ensure it is leak free Purge the mass flow controller with a dry inert gas for one hour before using corrosive gases IMPORTANT When installing the mass flow controller ensure that the arrow on the back of the unit shows the same direction as the gas flow 2 2 1 1 VCR COMPATIBLE COUPLINGS The AFC50 MD mass flow controller is normally supplied with 1 4 male VCR compatible couplings on both sides To install the AFC follow the steps listed below Refer to figure 2 2 1 Chec
9. low purity gas and or a corrosive gas Cleaning can be performed by removing the unit from the system cleaning inlet and outlet fittings separately and pumping alternately reverse and forward for 5 minutes in each direction with a solvent system one micron maximum absolute filtration Next the unit must be blown with Nz for 30 minutes minimum Reinstall cleaned fittings In extreme cases of contamination it may be necessary to separately clean the sensor the bypass and the valve 3 1 DISASSEMBL Y AND ASSEMBL Y PROCEDURES If you disassemble the mass flow controller it will need recalibration in order to reach the specifications given in this manual If the mass flow controller appears to have a fault first perform the checks in the troubleshooting section as it may not be necessary to dismantle the valve Prior to disassembly make sure the unit has been purged with a dry inert gas WARNING if it becomes necessary to remove the controller from the system after exposure to toxic pyrophoric flammable or corrosive gas purge the controller thoroughly with a dry inert gas such as nitrogen before disconnecting the gas connections Failure to purge the controller could cause a fire or explosion reasulting in death CAUTION the electronic circuitry contains CMOS and NMOS components These are easily damaged by static electricity and usual precautions should be taken when installing dismantling or adjusting the mass flow controller
10. or controller The electronics board amplifies and linearizes the sensor signal so the output of the electronics board named readout gives a signal proportional to the total flow circulating thru the mass flow meter or controller Most of the time this signal is a 0 5 V voltage signal 0 means no flow and 5 V means Full scale of the mass flow The full scale is the maximum flow for which the mass flow is designed and calibrated to work with a good accuracy It is always written on the stickers which are on the top of the cover and the side of the mass flow stainless steel base Also written on the sticker is the gas for which the mass flow is calibrated to work with AFC 202 D User s Manual 28 D 10 018 V04 Why using a bypass Because the sensor element can only measure small flow typically 5 sccm So the bypass allow to measure greater amount of flow On a 5 sccm full scale mass flow there is no bypass all the gas flows thru the sensor On a 100 sccm full scale mass flow the bypass is adjusted as when 100 sccm flow thru the mass flow 5 sccm will flow thru the sensor and 95 sccm will flow thru the bypass SENSORS PRINCIPLES Basically the sensor uses the thermal properties of a gas to directly measure the mass flow rate The sensor uses the basic principle that each gas molecule has a specific ability to pick up heat This property called the specific heat Cp directly relates to the mass and physical structure of the m
11. tighten the lower bellow to the stem coming out the top housing remove first the M3 nut putted during step 12 16 Adjust the lower bellow at 47 5mm as when it will be mounted into the housing 23 it should not be compressed or extended AFC 202 D User s Manual 19 D 10 018 V04 17 Assemble top housing to the housing 23 with O ring 27 on bellow assy and O rings 36 38 but without magnet in place for first leak test of O ring 26 Do not forget the snap ring on the top of the upper bellow stem 40 18 Assemble top housing with magnet in place Do not Install the O rings 36 with inert gas 19 Test valve 20 Do final leak test Note For leak testing of the AFC 202 normally close it is necessary to put power on it to open the valve or pumping down from inlet and outlet side at the same time 3 2 SENSOR CLEANING AND REPLACEMENT If it is determined that the sensor is contaminated flush with a solvent in hypodermic needle while running a small wire 0 15 mm diameter available on request Do not immerse the entire sensor assembly in a solvent the solvent will keep under the cover and destroy or at least change the sensor characteristics Slow dry with nitrogen If the sensor resistance has changed or even open circuit is measured the assembly should be replaced The measured resistance between red and green R1 and between red and yellow R2 must be between 160 and 190 Q and QR R2 R1 must be less than 1 Q Check also that there
12. all and its seat on top housing 24 Both parts should be polished without any scratch Place upper bellow 40 in top housing 24 3 Select number of washers M3 crown spring 30 and ball so that the end of the stem of the upper bellow assy is 1 to 1 5 mm below top surface of the top housing with ball on the seat 4 Select now place of the crown spring between the washers so that when the crown spring is on its seat the ball is lifted halfway the space adjusted in step 3 0 5 to 0 75 mm Note keep ball washers and crown spring together with nut M3 5 Now lengthen carefully the upper bellow so that it just contact the crown spring 6 Mounting assy in top housing 7 Place spring 6 over the upper bellow Add spring adjustment ring 31 and screw these over half way the thread length 8 Place the O ring over the upper bellow and put in place in the top Caution The O ring must be very clean clean with alcohol if necessary without any scratch Same think for its chamber in the top housing If not very small leak may occur and with time full the top housing with high pressure with consequence that the valve will stay permanently in open position 9 Place bushing 32 top ring 29 and the 4 M3 screws 9 do not yet tighten 10 Preparing lower bellow assy Be assured there is no gap between bellow and and the part screw at the bottom Unscrew and counter sunk the bellow part as necessary 11 Now screw and tighten the lower bellow to
13. and reliability in controlling high gas flows This range has been designed specifically to prevent contamination and particle deposition lt is therefore ideal when using in semiconductor and optical fiber manufacturing processes lt takes benefit from the digital technology new features such as alarm and maintenance functions are available with the free QUALIFLOW s PC interface digisoft With a specially developed algorithm the regulation is obtained without overshoot and during the transient time the readout matches the real flow 1 1 AFC 202 D USER s MANUAL This manual includes the following sections Section 1 Introduction contains specifications and calibration features Section 2 Installation contains all the information necessary to unpack the AFC202 D without causing contamination install the AFC202 D and check the installation before starting up All data related to digital card and use of a PC with RS232 connection are developed Section 3 Maintenance Section 4 Trouble shooting AFC 202 D User s Manual 5 D 10 018 V04 1 2 SPECIFICATIONS AFC 202 D Flow Range From 30 slm to 400 sIm N2 Control Range Between 2 and 100 F S Valve type Electromagnetic Valve Rest position Normally Open or Close Agouragy ere ate of F S 0 3 of F S if setpoint lt 30 of F S Linearity 0 2 F S per cal Gas Repeatability 0 15 F S Step Response Time lt 2 5 sec SEMI E17 91 Te
14. assembled calibrated packaged and controlled in a class 100 cleanroom 1 3 2 QUALITY CONTROL Each MFC is controlled 24 hours after manufacturing on a different calibration bench The accuracy the dynamic response the stability to pressure variations are double checked AFC 202 D User s Manual 7 D 10 018 V04 SECTION 2 INSTALLATION 2 0 INTRODUCTION This four part section contains all the information necessary to install the AFC202 D mass flow controllers 2 1 UNPACKING 2 2 MECHANICAL INSTALLATION 2 3 ELECTRICAL INSTALLATION 2 4 CHECK BEFORE START UP 2 5 DIGITAL CARD 2 6 COMMUNICATION MODES 2 1 UNPACKING The AFC202 D mass flow controller are manufactured under clean room conditions and has been packed accordingly upon receipt The cardboard packing should be checked for damage If there is visible damage please notify your local QUALIFLOW sales office at once In order to minimize contamination of clean rooms the unit has been packed in two separately sealed plastic bags The outside bag should be removed in the entrance to the clean room The second bag should be removed when you install the unit 2 2 MECHANICAL INSTALLATION 2 2 0 GENERAL Most applications will reguire a positive shutoff valve in line with the mass flow controller Pressurized gas trapped between the two devices can cause surge effects and consideration must be given to the sitting of the shutoff valve upstream or downstream
15. d to drive the control valve The control valve will proportionally open or close until the output is egual to the setpoint Note that valve can be normally open or normally close This is the position that will have the valve when the mass flow is not connected on power supply The valve can be actuated by a magnetic solenoid Then it can be normally open or normally close and response time of the valve itself is almost instantaneous In practise response time of the mass flow controller is limited by the response time of the sensor As sensor is based on thermal exchange it takes 1 to 5 s for the sensor to measure a gas change Several technigues allows to increase this response time and allow to get on the best mass flow response time bellow 5s The valve can be also made by a heating wire which heat a small tube then dilation will move a ball at the end of the tube This kind of valve can be only normally open and is guite slow Mass flow controller using such valve will have response time around 5 to 6 s for flow bellow 5 slm and up to 10 s for flow up to 5 sim However this technology is simple and reliable and can be recommend for many low cost application when response time is not critical AFC 202 D User s Manual 32 D 10 018 V04
16. e stem from 40 with ball O ring grove faced to the seat Look for contacting ball to seat And measure the exposed end of M3 from the stem length is A 23 Disassemble again Place now the ball 29 over the stem same way as above and screw a M3 nut on the stem Adjust nut to the same dimension as A 24 Measure space B between crown spring and ball Disassemble ball and nut M3 25 Prepare a package of small washes M3 27 to a thickness B Normal value 6 washers of 0 8 mm May be necessary to put 5 0 8mm 1 0 5mm or 5 0 8mm 2 0 5mm 26 Mounting assy in top housing 27 Place spring 6 over the upper bellow Add spring adjustment ring 31 screw these over half way the thread length 28 Place the O ring 26 over the upper bellow and put in place in the top housing Caution The O ring 26 must be very clean clean with alcohol if necessary without any scratch Same think for its chamber in the top housing If not very small leak may occur and with time full the top housing with high pressure with consequence that the valve will stay permanently in open position 12 Place package washers B O ring 28 and the ball over the stem and place M 3 nut to prevent dropping of the parts 13 Place bushing 32 topring assy 29 and the 4 M3 screws 9 do not yet tight 14 Preparing lower bellow assy Be assured there is no gap between bellow and the part screwed at the bottom Unscrew and counter sunk the bellow part as necessary 15 Now screw and
17. ers will help you to solve your problems regarding operation calibration connection gas flows gas mixture etc We deliver technical support or maintenance within 24 hours QUALIFLOW offers factory training on mass flow controllers Visit www qualiflow com and find your nearest repair and calibration center Hotline 33 0 4 67 99 84 31 AFC 202 D User s Manual 24 D 10 018 V04 APPENDIX A GAS PROCESS NUMBER Symbol Gas Name Number Density Sp Heat cC SEMI E52 cal g C 0298 Air 008 1 2929 0 2401 1 000 NH3 Ammonia 029 0 7710 0 519 0 68 Ar Argon 004 1 7842 0 1246 1 453 AsH3 Arsine 035 3 481 0 1178 0 666 BCI3 Boron Trichloride 070 5 26 0 130 0 40 CO Carbon Monoxide 009 1 2500 0 495 1 000 CCl4 Carbon Tetrafluoride 101 6 86 0 141 0 309 Cl2 Chlorine 019 3 209 0 116 0 83 B2H6 Dibirane 058 1 24 0 495 0 44 SiH2CI2 Dichlorosilane 067 4 54 0 141 0 43 CHF3 Fluoroform 049 3 125 0 173 0 506 CCI2F2 Freon 12 084 5 5 0 149 0 34 CF4 Freon 14 063 3 96 0 167 0 41 GeH4 Germane 043 3 423 0 138 0 58 He Helium 001 0 1788 1 242 1 454 H2 Hydrogen 007 0 0899 3 400 1 016 HCI Hydrogen Chloride 011 1 635 0 1937 0 981 C2F6 Hexafluoroethane 118 6 16 0 185 0 24 Kr Krypton 005 3 73 0 0596 1 45 CH4 Methane 028 0 7166 0 528 0 722 CH3SICI3 Methyltrichlorosilane 183 6 670 0 164 0 250 N2 Nitrogen 013 1 2503 0 2484 1 000 NO2 Nitrogen Dioxide 026 6 675 0 194 0 41 NF3 Nitrogen Trifluoride 053 3 173 0 178 0 434 N20 Nitrous Oxide 027 1 98 0 206 0 206 02 Oxy
18. full potential of digital technology Not only enabling digital communication these cards improve MFC accuracy and control using a numerical control algorithm They store several calibration curves therefore OUALIFLOW customers can reduce the number of references that they use They also make maintenance operations easier through alarm functions and PC diagnostic via RS232 The development of the digital technology has brought great improvements in e Accuracy Control e Additional capabilities This new digital card is 100 compatible with previous QUALIFLOW analog Mass Flow Controllers However the digital mode is best used for maintenance functions or in calibration mode The RS485 communication and the device net communication allow the use in digital communication mode with standard industry protocol 2 5 1 A BETTER ACCURACY All analog MFC s are calibrated with potentiometers at three points 2 50 and 100 FS to make the error at 0 25 50 75 under 1 FS The numerical MFC s are calibrated at more than 6 points and the response curve is then calculated Their accuracy is 1 of AFC 202 D User s Manual 12 D 10 018 V04 setpoint if setpoint gt 30 of F S 0 3 of F S if setpoint lt 30 of F S So the linearity is much better at small setpoints see the following graph Most of digital MFCs use linear interpolation to calculate the response curve whereas the QUALIFLOW digital board achieved better accuracy with
19. gen 015 1 429 0 2183 0 996 03 Ozone 030 PH3 Phosphine 031 1 523 0 2607 0 688 C3H8 Propane 089 1 98 0 392 0 35 SiH4 Silane 039 1 438 0 3188 0 596 SiF4 Silicon Tetrafluoride 088 4 68 0 168 0 35 Si2H6 Disilane 097 SO2 Sulphur Dioxide 032 2 91 0 149 0 67 SF6 Sulphur Hexafluoride 110 6 5 0 1590 0 27 TiCl4 Titanium Tetrachloride 114 8 465 0 22 0 30 C4F8 Octafluorocyclodutane 129 SiHCI3 Trichlorosilane 147 6 047 0 130 0 348 AFC 202 D User s Manual 25 D 10 018 V04 APPENDIX B EXPLODED VIEW OF THE AFC 202D AFC 202 D User s Manual 26 D 10 018 V04 e 1 lsem ooo 000204 Pinter mang e w A 1 Pvt iting 8 aso Outlet fitting 3 8 sw 500210005 sa i outer iting 38 VOR s0001 1203 Screw M3x8 hex head C 10A 1 Fitting plate assy AFM302VCR_ ull 1 O ring25x2 Viton o y O 14 2 Screws M3x16 panhead 15 2 ScrewsM3x10Hexhead 16 1 ScrewsM3x5Spanhead 17 2 ScrewsM4x10hexhead 18 4 ScrewsMSx10hexhead 20 1 Sticker name plate o 21 Sticker gas range amp S N ooo 22 1 Sticker pin assignment 25 1 Magnet actuator Normaly Open 500600001 NO__ 25A 1 Magnet actuator Normaly Close 500600001 NC O ring 20x2 Viton 808092043 ie l 33 ScrewM3x5panhead 35 4 screwM5x50hexhead 36A 0_ Donotuseonnormaly close a 4 mM AFC 202 D User s Manual 27 D 10 018 V04 APPENDIX C GENERAL MFC PRINCIPLES Mass Flow Con
20. is no short circuit between the tube and the red wire Examine the sensor seals and replace when damaged 3 3 VALVE CLEANING AND REPLACEMENT After having disassembly the valve the status of the shut off ball and the seat in the top housing can be examined The shut off ball can be cleaned with alcohol freon or even a HF solution 5 HF 95 deionised water The conical seat and the ball can be treated with solvent and a felt tip If appropriate polishing equipment is available the seat and shut off ball can be polished After polishing the parts must be cleaned If the critical parts are unfortunately corroded or attacked too much replace Afterwards follow assembling instruction and adjustment instruction AFC 202 D User s Manual 20 D 10 018 V04 SECTION 4 TROUBLESHOOTING 4 0 INITIAL CHECK 1 Check the gas supply pressure and check that the flow path to the mass flow controller has been opened 2 Ensure that the power supply and command signals are correctly transmitted to the D connector pins on the PC board 3 Check that the output signal matches the external reading For pin assignments see figure 2 3 Use the following table to locate the fault 4 1 SYMPTOMS Problem 1 Output reading without gas flow is not zero Possible cause Action 1 Gas flow is actually present Check closure of series shutoff valve 2 Zero reading has drift less than 1 5 Try Autozero function
21. ith flow because the gas flow is too fast and cool the 2 winded resistances instead of cooling the first one and heating the second one This is the reason why bypass is necessary for higher full scale than 5 sccm Also the fact that the coefficients N and Cp are different from one gas to another explains why mass flow can NOT be changed from one gas to another without using a special coefficient to converter the measurement or recalibrate the mass flow Because of sensor saturation if flow is ten time the full scale output will be almost no flow This will never happen on a mass flow controller as the valve of the mass flow will act as a restriction and will not allow the gas to flow ten times the full scale But it can easily happened on a mass flow meter as if there is no restriction on the gas line nothing in the mass flow meter will limit the gas flow BYPASS PRINCIPLES Acting as a restrictive element the bypass is composed of a series of capillary tubes held in a special bypass ring The ring fits around the body and may hold up to 24 tubes The number of tubes and their diameter depend on the customer s specifications of gas type and flow range For high flow rates the bypass tubes are replaced by washers screen bypass that also come in different slot sizes for different flow range Bypass ring Bypass tubes Bypass tubes O O O a Bypass washers equivalent to several thin tubes AFC 202 D User s Manual 31 D 10
22. k the gland to gland space including the gaskets 2 Remove the plastic gland protector caps 3 a When using loose VCR original style gaskets insert the gasket into the female nut b For VCR retainer gaskets snap the gasket onto the male coupling See figure 2 2 4 Tighten the nuts finger tight 5 Scribe both nut and body in order to mark the position of the nut AFC 202 D User s Manual 9 D 10 018 V04 6 While holding the body with a wrench tighten the nut 1 8 turn past finger tight for 316L stainless steel and nickel gaskets VCR retainer gasket Figure 2 2 VCR compatible couplings 2 3 ELECTRICAL INSTALLATION 2 3 0 GENERAL Within this section you will find the following sub sections Connections Digital functions Pressure control Ratio control Communication plug 2 3 1 CONNECTIONS The electrical connections of the AFC202 D are made through a sub D 15 connector see figure 2 3 RS 232 adapters for use in maintenance functions are available model 4 Digital s card sub D 15 connector 9 Signal Com a aga 10 Poner Com 3 TU 11 RS232 Tx 4 CND 12 Valve voltage sarees 5 15 VDC 13 TTL2 6 15 VDC del 7 RS232 Rx 15 TTL3 E 8 Setpoint Figure 2 3 Pin arrangement for digital Card connector Dedicated interface connector is available to allow digital MFC connection to work with other pin arrangement according to figure 2 4 This second pin arrangement is compatible with the AFC
23. lower calibration points thank to polynomial interpolation The RS232 or RS485 or Device net connection let you to change the calibration curve by choosing the corresponding number without disconnecting the MFC 10 calibration curves can be stored in memory To maintain the best accuracy the maximum factor between two full scales of two several calibrations is 3 The set point and the measure are converted by 16 bits CAN for the best accuracy The analog readout is converted by 12 bits CNA which does not alter the accuracy of the flow 5 0 _ 4 096 o 5 3 0 3s O 2 0 a Regular MFC 3 9 q 1 096 0 0 AFC 90MD zero drift 0 20 40 60 80 100 Flow of full scale 2 5 2 AN OPTIMIZED NUMERICAL CONTROL The control of the gas flow is made by a numerical algorithm which assumes a control without overshoot at any set point Each calibration curve is stored with its own optimised regulation parameters which are determined by calculation An analog control is fixed by the electronic components and can not be adapted to each gas and to each full scale For example an analog regulation can not avoid overshoot at low flow rates whereas an algorithm gives fine control at any set point The following typical curves compare the analog regulation with the numerical one As the response time of the digital MFC s are more repeatable and do not depend on electronic components So digital MFC s have closer transient behaviours
24. lter must be fitted in the gas line upstream of the MFC b Gas must comply with the following pressure specifications i Gas pressure must never exceed 10 bars ii Differential pressure must be more than 500 mbar for full scale flow through the MFC valve unless an other value is specified in the user s manual iii Differential pressure must be less than 3 bars for the MFC valve to regulate without gas flow oscillation unless an other value is specified in the user s manual iv Pressure at the mass flow inlet must be regulated by an accurate pressure regulator to prevent gas flow oscillation c Electrical connection requirements are as follows i The system must be wired carefully non observance of the pinout may irreversibly damage the electronic board inside the MFC in which case the warranty will be invalidated ii A stable power supply is required with ripple below 5mV AFC 202 D User s Manual 23 D 10 018 V04 d Gas connections the fittings must be handled carefully Qualiflow guarantees that all fittings have been individually inspected and are scratch free e Fitting procedure the fitting procedure set out in the manual must be followed meticulously Specifically the purge procedure is very important if corrosive gases or toxic gases are used f The mass flow must not be dismounted the MFC warranty will be invalidated if the seal between the MFC block and cover is torn 5 1 SERVICES QUALIFLOW Products Engine
25. me s ADJUSTABLE ALARM 2 5 8 2 TOTALIZER The totalizer indicates the cumulative flow in FS since the last initialisation It is useful to have a look on your gas consumption 2 5 8 3 DATA STORING RETRIEVING The set point the valve voltage and the readout are stored at a frequency of 2 times a minute during 6 hours and can be saved as an excel file These data allow the diagnostic of sensor drift or pressure drop For example an increasing in valve voltage for the same set point could be due to contamination or corrosion Data can be scanned and retrieved at any time without interruption while the MFC runs in control mode 2 6 COMMUNICATION MODES In addition to the ability to use this digital MFC on analog mode with the advantage of communication via serial RS 232C for maintenance calibration or individual control DB 15 connector following options are available RS 485 option can control up to 32 MFC s under MODBUS protocol RJ11 connector DeviceNet or PROFIBUS option this mode allows communication with high speed protocol For more information during utilization contact QUALIFLOW France AFC 202 D User s Manual 16 D 10 018 V04 SECTION 3 MAINTENANCE 3 0 GENERAL No routine maintenance is required on the meters or controllers other than occasional cleaning and re calibration After 3 or 4 years when the unit is run with a ultra clean and non corrosive gas After 1 or 2 years when the unit is run with a
26. mperature Range Between 5 and 50 C Temperature Coefficient lt 0 05 F S C Maximum Inlet Pressure 10 bar Min Differential Pressure 1 5 bar for 30 sim 2 bar for 50 slm 2 5 bar for 100 slm 3 bar for 200 sim 4 5 bar for 400 sim Pressure Coefficient lt 0 1 F S bar Power Input Requirement 15 VDC 15V 600mA Set Point Signal From 0 to 5 VDC Flow Outpout Signal From 0 to 5 VDC Electrical Connector Sub D 15 Construction materials 316L stainless Steel Leak integrity lt 2 10 8 sccm sec He Standard Seals 316L Stainless Steel Seals on request Neoprene for NH3 Viton for other gases Fittings On request Options Kalrez seals Separated electronics Device Net or PROFIBUS RS 485 MODBUS AFC 202 D User s Manual 6 D 10 018 V04 1 3 CALIBRATION FEATURES The Mass Flow Controllers are calibrated close to customer s process Without customer s information the MFCs are calibrated under standard conditions 1 3 0 STANDARD CONDITIONS Without special conditions specified by the customer the MFC is calibrated under the following standard conditions Pressure conditions Pressure Outlet Atmospheric Delta Pressure between 500 mbars and 3 bars Dynamic adjustment no overshoot The mounting position horizontal vertical inlet up or down should be specified by the customer to ensure the best accuracy 1 3 1 MANUFACTURING ENVIRONMENT The MFCs are
27. o correction flow rate sensor response after a long term drift 2 5 8 ADDITIONAL CAPABILITIES Additional capabilities are customized by a free PC Interface see the software s manual in the CD 2 5 8 0 LED INDICATOR The MFC contains three LEDS located on the left hand side The left LED is the watchdog LED When blinking it indicates whether the MFC is on power or not A quick blinking several times per second indicates that the MFC is working on a analog mode The second LED indicates whether the regulation is obtained switched on or not switched off Switched on the third LED indicates an error as a sensor error a communication error a EEPROM error a valve type error a converter A D error 2 5 8 1 ADJUSTABLE ALARM The user chooses three parameters the delta min the delta max and the delay alarm in order to adjust the regulation alarm Delta min and delta max in o FS are the maximum differences between the readout and the set point to get before the delay time If the MFC AFC 202 D User s Manual 15 D 10 018 V04 does not correctly control the alarm is on until the user switches it off For example if the pressure is too low the MFC could not regulate the flow The alarm signal will be generated until the user switches it off This alarm can be switched off by soft Readout F S Regulation LED off i Alarm on Delta Max F S EGNI WW WD O Delta Min 4 F S Ele Hd 0 Alarm Delay Ti
28. olecule and can be determined experimentally The specific heat is well known for many gases and is generally insensitive to changes in temperature or pressure By adding heat to a gas and monitoring the change in temperature the mass flow rate can be determined To illustrate this concept take the case of cool gas flowing through a heated tube Mathematically the heat loss can be described by the First Law of Thermodynamics q F Cp AT Where q is the heat lost to the gas flow F is the mass flow Cp is the specific heat for a constant pressure AT is the net change in gas temperature as it traverses the tube It is important to realize that both the specific heat and the flow rate determine the amplitude of the heat flux As the mass and physical structure of molecules vary widely from gas to gas so does the specific heat Cp For the same molar flow rate the heat flux can differ significantly for different gases If this heat flux is monitored the amplitude can be converted into an electrical signal Given that the specific heat is known for the gas then the mass flow rate can be determined directly from the electrical signal Now the MFC sensor includes capillary tube wound with two heated resistance and thermometers measuring the change in temperature distribution created by the gas flowing inside this tube heating current Sensor schematic For zero flow the upstream and downstream temperature will be eq
29. procedure 2 Incorrect setpoint on PC board pin 8 Check setpoint voltage 3 Incorrect supply pressure Check gas pressure at inlet side of mass flow controller 4 The Mfc is in digital mode and you use it with a set point voltage Change the control mode by the software 5 Incorrect flow reading Check the numerical readout found by the software is correct 6 Incorrect solder pad connections Check the strap configuration 7 The parameters max valve for a NC is too low The parameters min valve for a No is too high Increase or decrease one of this parameter by the software 8 Incorrect actuator voltage Voltage across actuator wires must be between OV and 30V Problem 5 Unstable control Possible cause Action 1 Unstable pressure Check inlet and outlet pressure stability 2 Defective electronics 3 Bad Regulation parameters Replace mass flow controller and contact QUALIFLOW for advice Contact QUALIFLOW 4 Defective Mechanics Contact QUALIFLOW For any other problems contact QUALIFLOW AFC 202 D User s Manual 22 D 10 018 V04 SECTION 5 WARRANTY AND SERVICES 5 0 1 PRODUCT WARRANTY Qualiflow products are guaranteed against defects in materials and workmanship if used in accordance with specifications and not subject to physical damage contamination alteration or retrofit Warranty periods from the date of
30. qualiflow AFC 202D QUALI FLOW Montpellier headquaters 350 rue A Nobel BP7 34935 MONTPELLIER CEDEX 9 France tel 33 4 67 99 47 47 fax 33 4 67 99 47 48 QUALI FLOW Inc 24 Goose Lane TOLLAND CT 06084 CALIFORNIA USA tel 1 860 871 04 01 fax 1 860 871 92 33 QUALI FLOW Technical Center 909 Boggs Terrace Fremont CA 94539 CALIFORNIA USA tel 1 510 440 93 74 fax 1 510 440 93 75 QUALI FLOW J apan 3F Hattori Bldg 4 30 14 Yotsuya Shinjuku ku Tokyo 160 0004 Japan Tel 81 0 3 5366 2801 Fax 81 0 3 3341 3513 AFC 202 D User s Manual D 10 018 V04 Identification D 10 018 03 07 02 User s Manual AFC 202D AFC202D Manual doc Control Approved Olivier L onel 03 07 02 Didier Stupfler 03 07 02 ae History Olivier L onel 17 11 00 Initial Version Issued Olivier L onel 18 01 01 Exploded View added Issued Olivier L onel 26 02 01 New section layout Issued Olivier L onel 03 07 02 Specification update Issued 2002 QUALIFLOW Montpellier France This document contains information proprietary to QUALIFLOW and shall not be used for engineering design procurement or manufacture in whole or in part without consent of QUALIFLOW AFC 202 D User s Manual 3 D 10 018 V04 SECTION t INTRODUCTION a ride 5 1 0 AFC 202 D DIGITAL MASS FLOW CONTROLLER ooocococcoccccnonnocnncnnonninnncnoninonnos 5 LL lt AFC 202 DiS USERSMANUA D ura 5 12 SPECIFICA MON slo 6 1 3
31. shipment are the following AFC90MD series 3 years AFC80MD AFC310MD series 2 years INFLUX AFC50 AFC202 AFC260 amp AFC261 series 1 year Buyers undertake to check and inspect the goods and to notify Qualiflow of shipment incidents by fax phone or e mail as soon as possible after receipting the goods During the warranty period products must only be repaired by authorized Qualiflow service centers otherwise the Qualiflow product warranty will be invalidated Repairs will be performed free of charge during the one year warranty period If MFCs are out of warranty Qualiflow will notify the owner of replacement or repair costs before proceeding Factory service and repairs are guaranteed 90 days The warranty excludes consumable materials and wear parts in teflon viton etc No MFC will be accepted for repair or warranty without a decontamination and purge certificate Each MFC is individually checked visual inspection of fittings helium leak test and flow calibration Qualiflow shall not be responsible for any damage caused by gas leakage or the use of a dangerous gas Users are responsible for following the safety rules applicable to each gas they use Improper use of a Qualiflow MFC will void the warranty and MFCs that have been damaged as a result of improper use will not be replaced by Qualiflow Specific warranty requirements are as follows a Gas must be clean and particle free which means a fi
32. the stem coming out the top housing remove first the M3 nut putted during step 4 12 Press on the stem so to center the ball into the seat then tighten the 4 screws 9 Tight the screws together in order to keep the inner assy in its centered position 13 Adjust the lower bellow length at 47 5mm as when it will be mounted into the housing 23 it should not be compressed or extended 14 Assemble top housing 24 to the housing 23 with O ring 37 on bellow assy and O rings 36 and 38 on top housing but without magnet in place for first leak test of the O ring 26 AFC 202 D User s Manual 18 D 10 018 V04 15 Assemble top housing now with O rings 36 and with magnet in place 16 Adjust valve according the normally open valve adjustment procedure then test the valve 17 Do final leak test Normally close valve 18 Check the quality of the contact between 3 8 ball and its seat on top housing 24A Both parts should be polished without any scratch 19 Place upper bellow 40 in top housing 24A and adjust bellow by pulling or pushing so that the top of the upper bellow stem 40 is adjusted to the top of the housing 24A 20 Remove upper bellow 40 21 Place washers M3 27 over stem and place crown spring 30 Add washers that crown spring 30 just touches the bottom of the bellow assy 0 5 mm Normal value 3 washers of 0 8 mm 22 Place the assy 40 up side down in top housing 24 and put on solid surface seat up Now place ball over th
33. trollers MFCs are used wherever accurate measurement and control of a mass flow of gas is required independently of flow pressure change and temperature change in a given range Mass Flow Meters MFMs are used wherever accurate measurement of gas is required without control of the flow which is done by another device To help understand how an MFC works it can be separated into 4 main components a bypass a sensor an electronic board and a regulating valve feedback circuit FIG 1 Schematic of the mass flow controller The bypass the sensor and one part of the electronic board are the measurement side of the mass flow controller and makes a Mass Flow Meter The regulating valve and the other part of the electronic board are the controlling side of the mass flow controller and exist only on a Mass Flow Controller So every Mass Flow Controller includes a Mass Flow Meter MEASUREMENT PRINCIPLES The flow is divided between a heated sensing tube the sensor where the mass flow is actually measured and a flow restriction or bypass where the majority of flow passes The bypass is designed in a way that flow thru the sensor and thru the bypass is always proportional to the flow range for which the mass flow is build The sensor is designed to deliver an output voltage almost proportional to the gas flow circulating thru it which is due to the bypass design proportional to the total flow circulating thru the mass flow meter
34. ual The windings are heated electrically to 80 C above the ambient temperature When the gas is flowing the upstream region cools down whereas the downstream region heats up causing a temperature gradient along the length of the tube see the sensor temperature profile figure AFC 202 D User s Manual 29 D 10 018 V04 2 Winded Resistances Wa meme i Sensor tube Flow in gt Fd gt TEMPERATURE NO FLOW Sensor tube Flowin gt gt mW R R R 8R SR 1 O sccm 2 Winded Resistances Sensor temperature profile The coils of the heating resistances are made with a thermal sensitive wire so that the temperature differences due to the flow are directly converted into resistances change Those resistance change are convert in voltage by a simple wheatston bridge working zone Sensor measurment 5 sccm Gaz Flow sensor response For flow under 5 sccm the measurement is proportional to the flow with a coefficient which depends on p Volumic mass of the gas Cp specific heat for a constant pressure AFC 202 D User s Manual 30 D 10 018 V04 N spin factor Constant which depend of the molecular structure of the gas and compensates for the temperature dependence of Cp Value of N Monoatomic gas 1 04 Diatomic gas 1 00 Triatomic gas 94 Polyatomic gas 88 For flow higher then 5 sccm the sensor is first non linear then the measurement starts to decrease w
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