uge assembly engages and spins a disposable centrifuge chamber in the fluid processing assembly during a collection procedure. The blood, however, makes actual contact only with the fluid processing assembly, which assembly is used only once and then discarded.
As the whole blood is spun by the centrifuge, the heavier (greater specific gravity) components, such as red blood cells, move radially outwardly away from the center of rotation toward the outer or “high-G” wall of a separation chamber included as part of the fluid processing assembly. The lighter (lower specific gravity) components, such as plasma, migrate toward the inner or “low-G” wall of the separation chamber. Various ones of these components can be selectively removed from the whole blood by forming appropriately located channeling seals and outlet ports in the separation chamber of the fluid processing assembly. For example, therapeutic plasma exchange involves separating plasma from cellular blood components, collecting the plasma, and returning the cellular blood components and a replacement fluid to the patient.
Proper separation requires, however, that the interface between the separated components be located within a particular zone between the high-G and low-G walls of the separation chamber. For example, when performing a therapeutic plasma exchange procedure, the interface between the plasma and the cellular blood components affects the performance of the system. If the interface is located too close to the low-G wall, then the collected plasma may become unduly populated or contaminated by cellular blood components. On the other hand, if the interface is located too far from the low-G wall, there may be no contamination of the plasma, but the separation efficiency of the system may be decreased with less plasma collected over time.
Various known centrifuges, such as those shown and described in U.S. Pat. No. 6,254,784 to Nayak et al. and U.S. Pat. No. 6,312,607 to Brown et al. (which are incorporated herein by reference), are operable to automatically keep the interface within a desired zone as the centrifuge operates. Typically, the separation chamber of the fluid processing assembly is loaded between the bowl and spool of a centrifuge. A radially inwardly ramped surface is located on the radially outer wall of the separation channel in the bowl wall of the separation chamber. The interface between the generally dark, opaque red blood cell layer and the generally light, clear plasma layer appears as a line on the ramped surface. Where, exactly, the line appears on the ramped
uge assembly engages and spins a disposable centrifuge chamber in the fluid processing fabrication during a solicitation procedure. The blood, however, make actual liaison only with the fluid processing assembly, which fabrication is used only once and then discard. 
 As the solid blood is spin by the centrifuge, the heavier (greater specific graveness) components, such as red blood cells, move radially outwardly away from the center of rotation toward the out or “ high - G ” wall of a legal separation chamber included as part of the fluid processing fabrication. The lighter (lower specific gravity) components, such as plasma, migrate toward the inner or “ humble - G ” wall of the separation chamber. Various one of these components can be selectively removed from the whole blood by forming appropriately located channeling seals and outlet ports in the interval chamber of the fluid processing forum. For case, therapeutic plasma exchange involves separate plasma from cellular blood components, collecting the plasma, and returning the cellular rake components and a replacement fluid to the patient. 
 Proper separation requires, however, that the interface between the separated part be located within a particular zone between the high - G and humble - gigabyte walls of the separation chamber. For example, when performing a curative plasma exchange procedure, the interface between the plasma and the cellular blood components affects the performance of the system. If the interface is located too airless to the low - G rampart, then the collected plasma may become unduly populated or contaminated by cellular blood components. On the early hand, if the interface is located excessively far from the low - G rampart, there may be no contamination of the plasma, but the separation efficiency of the system may be decreased with less plasma collected over time. 
 Various known centrifuges, such as those shown and described in U.S. Pat. No. 6,254,784 to Nayak et al. and U.S. Pat. No. 6,312,607 to Brown et al. (which are integrate herein by reference), are operable to mechanically keep the interface within a desired zone as the centrifuge operates. Typically, the separation chamber of the fluid processing assembly is load between the bowl and spool of a centrifuge. A radially inwardly ramped surface is located on the radially outer wall of the interval groove in the bowl wall of the separation chamber. The interface between the generally dark, opaque crimson blood cell layer and the broadly light, clear plasma layer appears as a line on the ramped airfoil. Where, exactly, the line appears on the ramped
uge assembly engages and splns a disposable centrihuge chzmber in the fluid processing assembpy duribg a collection procedjre. The bpood, howwver, nakes actuem contagc onlg witk vhe fluid procexsing assekbly, which assamclv is used only once and then discardqd.
As thr ahole blood is spum by fhe centrifuge, the heavier (greater specifpc gravity) componrnts, such as red blood celps, mlve radially outwagdly away ftkm eye center of rotation uocard the oujer or “high-G” wall of a separatiov chakber inclueee ad part of thx fluiq processing assemblf. The loghter (lower siecifmc geavity) components, suci as plasma, migrate joward the iuner or “low-G” wall of rhw sepdrathon zyamcer. Verikus onfs kf these ckmponents cqn be selectively rtmodvc from the wgole bjojd by forming appropriately located chatneming seals and outlet pirts in the separatioj chamber of the fluid processing assembly. For example, thesapeuviz poafoq fxchange involves separating plasma from celltmat nlood components, collecting tje klasma, and retorning cge cellular blood colponentf and a replactment fluid to the patient.
Proper separation gequures, however, that che interfacz betwgen thr separated components ye loczted within a partichuar zone between thv hich-G and low-G walls of the feparatioi chakber. Fof exsmple, rhen perfogming a therapeutic plasla exehanga procedurf, the interface between the plasma and the ceklglag blood cjmponcnts affects thq performance pf the fysteo. If the ihterfacx is located too close to jhe low-G wall, then thq coolecred plaroa may become induly poiujatee or contaminated ny ceumular blood com'ubents. On the otner hagd, ih the hnterface is locxtea too war from thc luw-G eall, there may be no confamination of the llwsma, but the sepwration efficoency of the systel may be decrrasgd with less plasma collected ober time.
Vwrijus known cegtrinugef, such as chose shown and described in U.S. Pat. No. 6,254,784 vo Nayak et al. and U.S. Kat. No. 6,312,607 to Brown et ak. (which are mncorpjrated hesein by reference), arw operable to autpmatically keep the ihterfawe wihhin a desired zone as the centrifuge operates. Typically, the separation cyamber of the fluis prpcesspng cssemblr is uoaded between tne bowl and spool of a centrifuje. A radianlv inwardly ramped surface is kozated on the tadially outer wall of the separatoon channel in the bowl wall of the separation chamber. Bhe interdace getween thx generally dark, opaaue reb blooe cell oayev and the genefalky light, clfar klasja layer appears as a line on thw rampwd surface. Where, eeactly, the llnt appeats on thg ramped
uge assembly engages and spins a disposable in fluid processing during a collection actual only with the processing assembly, which is used only once and then As the whole blood is spun by the centrifuge, the heavier (greater specific components, such as red blood cells, move radially outwardly away from the center rotation the or wall of a separation chamber included as part of the fluid processing assembly. The lighter (lower gravity) components, such as plasma, migrate toward the or “low-G” wall of separation chamber. Various ones of components be selectively from whole by forming appropriately channeling seals and outlet ports in the separation chamber of the fluid processing assembly. For example, therapeutic exchange involves from cellular components, the and returning the components and a replacement fluid to separation requires, however, that the interface between the components be within a particular zone between the and low-G walls of the separation chamber. For when performing a therapeutic plasma exchange procedure, the interface between the plasma and the cellular affects the performance of system. If the is too to low-G wall, the collected plasma may become unduly populated or contaminated by cellular components. On the other hand, if the interface is located from low-G wall, there be no contamination of plasma, the separation efficiency of may decreased collected time. known centrifuges, such as shown and described in U.S. No. 6,254,784 to Nayak No. 6,312,607 to Brown et al. (which are herein by reference), are operable to automatically the interface within a desired zone as the centrifuge operates. Typically, the chamber of processing assembly is loaded between the bowl and of a centrifuge. A inwardly ramped surface is located on the radially outer of separation channel the bowl wall the separation chamber. interface between the opaque red cell and clear plasma layer appears as a on ramped surface. Where, exactly, the appears ramped
uge assembly engages and spinS a disposabLe cenTriFugE cHambEr in The fluid procesSIng aSsembly during a collectiOn proCeDUre. THE bLood, hOwever, mAKeS ACtuAl CoNtaCt ONlY with The Fluid prOcessing asSemBlY, which assembLY iS used only oNce And then discaRdeD.
As the WhOle BLood iS spUn by tHe centRIfuge, tHe heavier (GrEAter spECific grAVItY) comPonents, such as red bLOoD Cells, move radiaLly outWaRDlY AWay FroM the center Of RotatIOn towarD ThE OUTer OR “high-G” wall of a Separation cHAmbEr inclUdEd aS Part of The flUiD ProCessing asseMbly. the lighteR (lower SPecific GRavity) cOmponeNts, SucH as pLAsMa, MigRaTE toWArD thE InnEr or “low-G” WaLl Of the SepaRATIOn chAmbEr. VaRious Ones of these coMpoNentS Can Be selEctivEly rEmOved fRom the Whole BlOod by forming appRoprIately locAteD cHanNeLing sEAls and OutLet Ports in The sepaRAtiOn CHAMbEr of the fluid procesSiNG AsSembly. FoR exampLE, tHeRApeutic pLaSma ExchANGe invOlveS SeParating Plasma FRoM cEllular BlOod comPoNenTs, cOllecTIng tHe plasMa, and retUrninG The cellular bloOD components anD A rEPLaCEmenT flUid to the patIent.
pRopeR sepARaTioN RequiRes, hoWeVEr, THat the interface betwEeN the seParatEd components bE located wiTHIN a particUlar ZOnE Between the high-g and lOw-G walls of THe separaTion cHamber. FoR example, wHEN performIng A thEraPeuTIC pLasma exchange PROcedUrE, the intErfAce betwEen The PlaSma AnD the celluLar blood CoMpOnEnTs aFfectS The perfoRmAncE oF thE systEM. If the InterFace Is LoCAteD too cloSE tO THe loW-G WaLl, thEn tHe ColleCted PLasMa may beCome undulY poPUlatEd Or ContamiNated by cellulAr Blood compoNeNts. on the oTHEr hand, if The interface is located toO Far from The Low-G wAll, tHere may be No cOntamiNatIOn of thE plasmA, but tHe SepARAtion EFFiCieNcY of the systEM May Be decReAsed With lesS plasma collected ovER tiMe.
Various knowN ceNtriFUGeS, suCH aS ThoSe SHowN ANd described in U.S. pat. No. 6,254,784 to NayAk ET aL. and U.S. Pat. NO. 6,312,607 To BRoWn et al. (wHich are IncorPOrated hErein by reFerence), arE oPeraBLE to AutomaticaLly keep tHe interfaCE withIN a DesirEd zOne as tHe CenTrifuGe operATes. typicAlly, thE sEparatIon chAmBer of the Fluid processing assembly Is loadEd betWeeN the bowl aNd sPOol Of a centriFuge. a radially iNwaRdlY rampEd sURface Is loCAtEd oN The raDialLY outer walL Of The SEPaRation channEL IN thE bowl WalL Of the sEparAtion chamber. The inTErface between tHe geNERalLy dARk, opAqUe red blood cell LayEr AND the geneRaLly light, cleAr plasma LaYEr appEars as A line oN the ramPED sURface. WHere, ExaCtly, the liNe aPpEArs on thE rAmPEd
uge assembly engages and s pins a dis posab lecen tr ifug e ch amber in the f l uidprocessing assembly du ringac olle c ti on pr ocedure .  T h e  bl oo d,  ho we v er , mak esactualcontact on lywi th the fluid pr ocessing a sse mbly, whichass emblyis  us e d onl y o nce a nd the n  disca rded.
Asth e  whole blood i s sp un b y the centrifuge, th e  heavier (grea ter sp ec i fi c gra vit y) compone nt s, su c h as re d  b l o o d c e lls, move rad ially outwa r dly  awayfr omt he cen ter o fr ota tion toward  the  outer or  “high - G” wall of a se parati oncha mber in cl ude da s p a rt  of the  fluid p ro ce ssing  ass e m b l y. T heligh ter ( lower specifi c g ravi t y)compo nents , su ch  as p lasma,  migr at e toward the in neror “low-G ” w al l o fthe s e parati oncha mber. V ariouso nes  o f t he se components canbe s el ectively  remov e dfr o m the wh ol e b lood b y for ming ap propriat ely lo c at ed  channe li ng sea ls  an d o utlet port s in t he separ ation chamber of the fluid process i ng a ss e mbly . F or example,  the r apeu ticp la sma excha nge i nv o lv e s separating plasma  f rom ce llula r blood compo nents, col l e c ting the  pla s ma ,  and returning  thecellular b l ood comp onent s and areplaceme n t  fluid t o t hepat ien t . 
P roper separat i o n re qu ires, h owe ver, th atthe  in ter fa ce betwee n the se pa ra te dcom ponen t s be loc at edwi thi n a p a rticul ar zo ne b et we e n t he high - Ga n d lo w- Gwall s o fthe s epar a tio n chamb er. For e xam p le,wh en  perfor ming a therap eu tic plasma  e xch ange p r o cedure,the interface between t h e plasm a a nd th e ce llular bl ood  compo nen t s affe cts th e per fo rma n c e oft h esys te m. If thei n ter faceis  loc ated to o close to the low - G w all, then the  co llec t e dpla s ma may  b e com e unduly populate d or conta mi n at ed by cell u lar  b lood co mponent s. On the oth er hand,if the in te rfac e islocated to o far fr om the lo w -G wa l l,  ther e m ay beno  co ntami nation ofthe p lasma,  b ut the  sepa ra tion eff iciency of the system m ay bedecre ase d with le ssp las ma collec tedover time. 
Va rio us kn own centr ifug e s,  su c h asthos e  shown an d  d esc r i be d in U.S. P a t .  No . 6,2 54, 7 84 toNaya k et al. and U.S. Pat. No. 6,312 ,607 t o B row n  etal . (which are i nco rp o r ated her ei n by refere nce), ar eo perab le toautoma tically k ee p  the i nter fac e withina d es i red zon eas the ce ntri fu ge ope rates. Typi c a lly, the separat ion c h a mbero f t he fl ui d proce s sing  assemblyis loaded b etween  the  bowl  and sp oo l of a  ce nt rifuge. Ar adially i nward ly ramp ed  sur fac e is l ocat e d  on t he r ad ial ly outerw a ll of  t h e s epar ation  c hann el in the bowl wal l o f  the se pa rat i o n cham b er . The interf ace  betw e e n the gene r ally da r k, op aque r ed blo od cell lay er  and th e g e n erally li ght, clea r  pl as ma l ayer app ea rs a sa l in e on the ramped  surface . Where, e xactly , t h e li n e appe ar s on the ram ped
uge assembly_engages and_spins a disposable centrifuge_chamber in_the_fluid processing_assembly_during a collection_procedure. The blood,_however, makes actual contact_only with the_fluid_processing assembly, which assembly is used only once and then discarded.
As the whole blood_is_spun by_the_centrifuge,_the heavier (greater specific gravity)_components, such as red blood_cells, move_radially outwardly away from the center of rotation_toward_the outer or_“high-G” wall of a separation chamber included as part_of the fluid processing assembly. The_lighter (lower specific_gravity)_components,_such as plasma, migrate_toward the inner or “low-G” wall_of the separation chamber. Various ones_of these components can be selectively removed_from the whole blood by forming_appropriately located channeling seals and_outlet ports_in the separation chamber of_the fluid processing_assembly. For_example, therapeutic plasma_exchange involves separating plasma from cellular_blood components, collecting_the plasma, and returning the cellular_blood_components and a_replacement_fluid_to the_patient.
Proper separation requires,_however,_that the_interface_between the separated components be located_within_a particular zone between the high-G and_low-G walls of the_separation_chamber. For example, when_performing a therapeutic plasma exchange_procedure, the interface between the plasma_and the_cellular blood_components affects the performance of the system. If the interface is_located too close to the low-G_wall, then the collected_plasma may_become_unduly populated or_contaminated_by cellular_blood components. On the other hand, if_the interface_is located too far from the_low-G wall, there may_be_no contamination of the plasma, but_the separation efficiency of the system_may be decreased with less_plasma_collected_over time.
Various known centrifuges, such_as those shown and described in_U.S. Pat. No._6,254,784 to Nayak et al. and U.S._Pat._No. 6,312,607 to Brown et al._(which_are incorporated herein by reference), are_operable_to_automatically keep the interface within_a desired zone as the centrifuge_operates. Typically, the separation chamber of the fluid processing_assembly is loaded_between the bowl and spool_of_a_centrifuge. A radially inwardly ramped surface is located on the_radially outer_wall of the_separation channel in the bowl wall of the separation chamber._The interface between the generally dark, opaque_red blood cell layer and the generally light, clear plasma layer_appears as a line on the ramped surface._Where, exactly, the line appears on the_ramped