DAQ_KHOA

B GIO DC V O TOTRNG I HC S PHM K THUT TP.HCMKHOA IN-IN T

TIU LUN MN O LNG THNG MINH

NGNH: K THUT IN TLP CAO HC IN T 13B ti:TM HIU H THNG THU THP D LIU

GVHD: TS. NG VN THUYNHVTH: NGUYN NG KHOA 13852020301

Tnh sn sng cao trong h thng mng doanh nghip

TP. HCM, Thng 06 nm 2014Trang 2

CHNG 1TNG QUAN1. Tng quan v h thu thp d liu (DAQ)1.1 Cc thnh phn ca h DAQ1.1.1 nh nghaThu thp d liu (data acquisition) l qu trnh m tn hiu vt l t th gii thc c chuyn thnh tn hiu in o lng v chuyn sang tn hiu s cho qu trnh x l, phn tch v lu tr bng my tnh.Trong hu ht cc ng dng, h thu thp d liu (Data Acquisition (DAQ) System) c thit k khng nhng ch thu thp d liu m cn c chc nng iu khin. V vy khi ni h DAQ thng hm c chc nng iu khin (Data Acquisition and Control).1.1.2 Cc thnh phn ca h DAQMt h DAQ c xy dng trn c s sc mnh ca my tnh bao gm nhiu khi phn cng t cc nh sn xut khc nhau. Nhim v ca cc nh tch hp l kt hp cc khi phn cng ny thnh mt h thng hon chnhCc thnh phn c bn ca mt h DAQ l : Cm bin v cc b chuyn i Dy ni v truyn thng Khi x l tn hiu Phn cng thu thp d liu PC (h iu hnh) Phn mm thu thp d liu

Hnh 1.1: S chc nng ca h DAQChuyn i v cm bin B chuyn i v cm bin cung cp mt kt ni (thc) gia th gii thc v h DAQ nh vo vic chuyn i cc i lng vt l sang tn hiu in m b x l tn hiu v/hoc h DAQ chp nhn.Cc b chuyn i hin ti c th s dng cho hu ht cc php o vt l v cung cp tn hiu in tng ng. V d: cp nhit, nhit in tr v IC nhit chuyn i nhit sang mt tn hiu in analog, trong khi b o lu lng (flow meter) cung cp mt tn hiu chui xung c tn s ph thuc vo tc ca dng chy.Trong mi trng hp trn, tn hiu in u ra t l vi i lng vt l c o lng theo quan h nh trc.Dy ni v cp truyn thngDy ni: Lin kt ng ra ca chuyn i/cm bin n phn cng khi x l tn hiu hoc t khi x l tn hiu n PC nu khi x l tn hiu cch xa PC. Trng hp phn cng khi x l tn hiu cch xa PC v chun truyn tn hiu l RS-232 hoc RS-485 : cp truyn thng.y thng l thnh phn cng knh nht ca h thng v thng d chu tc ng ca nhiu bn ngoi c bit trong mi trng khc nghit v vy cn quan tm c bit n vn chng nhiu cho dy ni v cp truyn thng gim thiu nh hng ca nhiu.Khi x l tn hiuTn hiu in u ra ca cm bin cn c chuyn sang dng thch hp, c chp nhn bi phn cng khi thu thp d liu, c bit l b chuyn i A/D. Cc nhim v ca khi ny c th l: Lc Khuych i Tuyn tnh ha Cch ly Kch thchPhn cng thu thp d liuChuyn tn hiu dng tng t sang dng s hin th, lu tr v phn tch.c vo tn hiu s cha ng thng tin v qu trnh ca mt h thng. Chuyn tn hiu s t PC sang tn hiu iu khin iu khin mt h thng hay qu trnh. Xut ra tn hiu iu khin dng s.Phn cng thu thp d liu tn ti di nhiu hnh thc khc nhau t nhiu nh sn sut, c th l: card giao tip m rng (plug-in expansion bus boards), intelligent stand-alone loggers and controllers (loi ny c th c nh cu hnh, quan st v iu khin t my tnh qua RS-232 hoc c th hot ng c lp), hoc cc thit b c lp t xa c th iu khin v nh cu hnh t my tnh qua chun giao tip IEEE-488.Phn mm thu thp d liu: c ba la chnc v xut d liu trc tip dng: assembly, hoc cc ngn ng cp cao nh Pascal, C/C++Dng driver i km vi phn cng cung cp bi nh sn xut.Dng gi phn mm ng dng cung cp km vi phn cng thu thp d liu thc hin tt c cc nhim v yu cu cho mt ng dng c th.PC: nh hng rt ln n tc thu thp v x l d liu.1.1.2 Cu trc ca h DAQ1.1.2.1 Vo/ra ti ch (tp trung) vi PCCc mch vo/ra tp trung c cm trc tip vo my tnh qua cc bus m rng. Chng c c im l nh gn, tc thu thp d liu v iu khin nhanh nht, chi ph thp v vy thng c dng. Chng thng c s dng trong cc ng dng m PC gn cm bin v c cu chp hnh.

Hnh 1.2: S vo/ra tp trung1.1.2.2 Vo/ra phn tnSensor v c cu chp hnh thng xa PC, thng trong mi trng sn xut CN, cm bin v c cu chp hnh trong mi trng khc nghit v bao ph trong mt din tch rng cch xa PC hng trm mt.Trong mi trng c nhiu, kh c th nhn c tn hiu nh t cc cm bin nh cp nhit, strain gauge qua ng truyn di.Dy ni t sensor v PC di v c th tn km.Gii php: Vo/ra phn tn, ngha l module x l tn hiu c t gn mi sensor tng ng. Mi sensor cn c mt module x l tn hiu.Gii php ny c th tn km nu c nhiu sensors nhng c b p bi cht lng tn hiu v chnh xc.Dng thng gp ca vo/ra phn tn l b pht s. B pht s ny thc hin tt c cc chc nng x l tn hiu cn thit, c VXL v ADC chuyn tn hiucn o sang dng s. Tn hiu dng s ny c truyn v PC bng chun RS-232 hoc RS-485.RS-232 (point to point) th cng knh khi c nhiu im.i vi RS-485, n gim lng cp truyn, c th kt ni n 32 modules, khong cch truyn c th ln n 10km nu dng multi-drop network. (RS-232: ti a 15m). Thng cn b chuyn i RS-232 sang RS-485 do hu ht cc PC khng h tr chun RS-485.

Hnh 1.3: S khi vo/ra phn tn1.1.2.3 Cc b thu thp d liu c lp hoc phn tnCc b thu thp d liu c lp hoc phn tn c u im ging ca I/O phn tn vi cc b x l tn hiu thng minh, ng thi kh nng t quyt nh t xa lm tng tin cy ca h thng.C th iu khin v nh cu hnh t my tnh dng giao tip ni tip hoc card PCMCIA. Chng c th hat ng c lp m khng cn PC (y l mc tiu chnh) v vy rt hu ch khi phi t cc b thu thp d liu xa hoc trong mi trng khc nghit hoc cc ng dng khng cho php s kt ni lin tc ti my tnh ( ex: iu khin nhit trong cc xe ti ng lnh).S dng card PCMCIA nhp d liu t b thu thp d liu c lp.

Hnh 1.4: Card PCMCIA nhp d liu t b thu thp d liu c lpS b thu thp d liu c lp qua giao tip ni tip RS - 232

Hnh 1.5: S b thu thp d liu c lp qua giao tip ni tip RS 232Kt ni b thu thp d liu c lp qua mng in thoi hoc radio

Hnh 1.6: Kt ni b thu thp d liu c lp qua mng in thoi hoc radioPhng php tng t ca chng trnh hoc ng nhp d liu t mi logger/controller l c sn hoc thng qua mng truyn thng ni tip hoc thng qua s dng di ng v ti s dng th nh.

Hnh 1.7: Mng vo/ra phn tn1.1.2.3 Cc thit b theo chun IEEE-488Chun truyn thng ny cn c gi l GPIB (General Purpose Interface Bus), c thnh lpnm 1965 bi Hewlett-Packard kt ni v iu khin cc thit b o th lp trnh c ca hng. Chun ny nhanh chng c th gii chp nhn v tr thnh chun IEEE-488 nh tc , tnh linh hot v hu ch trong vic kt ni cc thit b trong phng th nghim.GPIB l chun giao tip truyn thng song song tc cao cho php kt ni ng thi 15 thit b trn bus truyn d liu song song.Chun IEEE-488 thng yu cu c b iu khin GPIB nh a ch cho tng thit b v khi to cc thit b s truyn thng vi nhau.Tc truyn thng ti a, chiu di cp truyn ti a, khong cch ti a gia cc thit b ph thuc vo tc v kh nng x l ca b iu khin GPIB v loi cp truyn. Cc thit b theo chun IEEE-488 ph hp cho cc lab nghin cu hoc o th trong cng nghi v c hng ngn sn phm trn th trng h tr chun giao tip ny.

Hnh 1.8: Cu trc h GPIB thng dngCc dng c lp trnh c IEEE-488

Hnh 1.9: Card thu thp d liu h tr IEEE-488

Hnh 1.10: B iu khin p sut Druck DPI 5151.1.3 Khu iu ha tn hiuTn hiu in ng ra ca chuyn i/sensor cn c bin i cho ph hp vi ng vo ca phn cng DAQ. Mt s chuyn i/sensor cn ngun kch thch hoc cu Wheatstone v tuyn tnh ha tn hiu o c chnh xc. Hu ht cc h DAQ u bao gm khu x l tn hiu di mt hnh thc no .Cc chc nng c bn m khu x l tn hiu c th thc hin l: Khuch i Cch ly Lc Kch thch Tuyn tnh haKhu x l tn hiu ca h DAQ phi thc hin nhim v no v cch thc thc hin ph thuc vo s lng v loi chuyn i/sensor, yu cu v ngun kch thch v ni t cho sensor, ng thi khng km phn quan trng l khong cch t cm bin ti PC trung tm.1.1.3.1 Khuch iKhuch i l nhim v chnh yu ca khu x l tn hiu nhm thc hin 2 chc nng quan trng sau: Tng phn gii cho php o. V d nh tn hiu ng ra sensor 0-10mV nu a trc tip vo ADC 12bit vi full-scale 10V ( phn gii 2.44mV ): ch phn bit c 4 mc. Tng t s tn hiu/nhiu (SNR). tn hiu nh ng ra ca sensor cch xa phn cng DAQ nu c truyn trong mi trng nhiu s b nh hng ln ca nhiu. Nu tn hiu nh (b nhiu) ny c khuch i ti phn cng DAQ sau khi c truyn qua mi trng nhiu th nhiu trong tn hiu ny cng c khuch i nh tn hiu cn o. Nu nhiu so snh c vi tn hiu cn o ( SNR thp) s dn n sai s ln cho php o v php o l v ngha.Tng SNR bng cch khuch i tn hiu nh u ra sensor trc khi truyn.VD: Cp nhit loi J c nhy 50uV/0C. Nu tn hiu u ra cp nhit c truyn trong mi trng c nhiu ln vi khong cch 10m, nhiu t ln tn hiu ca cp nhit c th ln n 200uV dn n sai s n 4oC. Nu khuch i tn hiu ti u ra cp nhit ln 500 ln th nhy lc ny l 25mV/0C, sai s do nhiu lc ny (hng uV) l rt nh.1.1.3.2 Cch lyCch ly gip bo v thit b phn cng DAQ, PC cng nh ngi vn hnh khi in p cao trong qu trnh qu , st hay tnh in cng nh hng hc ca cc thit b cao p.Cc b bo v qu p c t u vo ca khu x l tn hiu bo v khu ny. Cch ly cn nhm m bo vng ni t, in p cch chung (xt phn sau) khng nh hng n tn hiu o.C nhiu cch cch lyCch ly dng Opto thng dng cho tn hiu s.

Cch ly bng phng php t trng/in trng dng cho tn hiu tng t: iu ch tn hiu in p thnh tn s, sau truyn tn hiu tn s bng bin p/t v bin i tn s thnh in p u ra.

Hnh 1.11: Cch ly bng my bin p1.1.3.3 Mch LcMch lc nhm loi b nhiu ra khi tn hiu cn o trc khi tn hiu ny c khuch i v a vo ADC. C th lc bng phn cng hoc phn mmLc mm: c tn hiu o nhiu ln hn cn thit v ly trung bnh. Phng php ny loi b c nhiu tun hon hon ton nu cc mu c trung bnh ha trong mt chu k ca nhiuLc bng phn cng: cc mch lc analog (passive and ative) l r nht, cc thng s: Tn s ct Roll-off: dc ca ng cong bin theo tn s ti tn s ct Q-factor: quyt nh li ca mch lc ti tn s cng hng v roll-offMch lc thng thp

Mch lc thng cao

Mch lc Butterworth

1.1.3.4 Tuyn tnh haQuan h gia ng ra ca sensor v tn hiu u vo cn o thng l phi tuyn. Phm mm ca h DAQ thng thc hin chc nng tuyn tnh ha.Nu mi quan h phi tuyn l d on c v c tnh lp li th c th tuyn tnh ha bng phn cng. Thng thng cn mt b x l tn hiu c lp trnh dnh ring cho mt b chuyn i ring bit, tuy nhin sau khi c x l th cc tn hiu o lng ny c quan h trc tip vi i lng ang o.Trong hu ht cc ng dng v o lng th vic tuyn tnh ha bng phn mm c s dng vi 2 k thut chnh l dng bng tra: thi gian thc hin nhanh nhng cn dung lng b nh ln hoc b bng a thc: cc a thc vi bc c la chn ty loi cm bin.1.4 Chng nhiu v ni dy cho ng vo analog1.4.1 Phn loi nhiuNhiu l tn hiu in khng mong mun trong mch. Khng th trit nhiu hon tan m ch c th gim bin nhiu cho n khi bin ca n khng gy nh hng ln tn hiu o.Cc thnh phn tham gia qu trnh sinh nhiu

Cc hnh thc gy nhiu thng gp trong h DAQ Ghp ni h cm (inductive coupling) Ghp ni in dung (capacitive coupling) Ghp ni in tr (conductive coupling)Ghp ni in tr

Ghp ni in tr xy ra khi hai hoc nhiu mch cng chia s tn hiu hi tip chung. trong trng hp nh vy, dng in hi tip t mt mch, chy qua cc tr khng hu hn ca tn hiu hi tip chung, kt qu l lm thay i in th ni t. n kt ni hng lot ni t dn n khp ni dn n ghp ni in tr. Nu in tr ca hi tip chung l 0.1 v dng in hi tip l 1A th in p o c t cm bin nhit l 0,1l=100 mV, tng ng vi sai s l 10 trong cm bin nhit .Ghp ni in dung

Vng in t xy ra trong vng ln cn ca cc ngun in p khc nhau. Ghp ni in dung l vic truyn nhiu bn ngoi thng qua in dung chung gia ngun nhiu v mch nhn. Kt ni vt l ca ghp ni in dung nh hnh 1.12

Hnh 1.12: Kt ni vt l ca ghp ni in dungMch in tng ng ca ghp ni in dung vo mch tn hiu

Ghp ni h cmGhp ni t trng hoc ghp ni h cm l k thut m thi gian thay i dn n dng in thay i sinh ra t trng trong ngun nhiu, kt ni vi cc dng in hi tip ca mch nhn. Kt ni vt l ca ghp ni h cm nh hnh 1.13

Hnh 1.13: Kt ni vt l ca ghp ni h cm

Dy cp cung cp mt dng in hi tip di nht v mnh nht. Tc ng ca ghp ni h cm l minh chng tt nht khi xem xt mch in hnh 1.14, trong tn hiu cp c ghp li bi t trng thay i dng sin vi mt thng lng nh l .

Hnh 1.14: M hnh mch tng ng ca ghp ni h cm gia ngun nhiu v mch tn hiu

Trong :L tng nht, in p trn ti l VS (tn hiu in p ngun). Tuy nhin, t thng gy ra mt in p trong vng lp, n xut hin cng vi cc mch tn hiu thu. in p xut hin trn ti l tng ca ngun in p v t trng cm ng in p khng mong mun (VN).Xon cc dy dn cch in ca vng lp vi nhau, nh th hin trong hnh 1.15, c th lm gim ng k s lng ghp ni h cm trong ng tn hiu.

Hnh 1.15: Gim nhiu ghp ni h cm bng dy xon1.4.2 Gim nhiuDng cp c v bc v ni t v bc : gim nhiu do tng h in dung gy ra

Cng thc in p nhiu l: Ni t v cp

Dng cp c v bc v xon iDng cp xon iDng cp ng trc2 Cc loi cm bin o nhit , khi lng2.1 Cc loi cm bin o nhit 2.1.1 Thermocouples (TCs)Cp nhit ngu c cu to gm 2 dy kim loi khc nhau c ni chung (v in) mt u v u cn li c kt ni chung (v nhit) nh c biu din bn di.

V = VA - VB n gin ha vic s dng TC, ngnh cng nghip to ra mt s cp nhit in tiu chun, vi cht ha hc tiu chun cung cp php o lp li v d on c. Nhng TC thng c i din bi mt t duy nht. Loi cp nhit in ph bin bao gm: J, K, T , E, R , S , v N. Mc d rt nhiu cc TC a ra dung lng tng t, mi ci c mt s kt hp khc nhau ca cc yu t t l, chnh xc tng th, phm vi nhit o v chi ph.Bng 1: Cc tnh cht cp nhit in

Cp nhit da trn o nhit l mi h thng bao gm nhiu hn mt cp nhit in. Cp nhit in o chnh c to ra vo thi im m hai kim loi khc nhau c c kt ni. Tuy nhin, hai cp nhit in thm vo c to ra khi dy cp nhit in chnh c gn vo h thng DAQ.Nhng cp nhit in "khng mong mun" c gi l "lnh". Hnh 1.16 m t mt cu hnh u vo cp nhit in cho thy c hai chc nng cp nhit in l "o" v "lnh". Chc nng lnh cng to ra mt in p u ra, nu khng b, tr thnh mt tn hiu li.Loi b cc li chc nng lnh c gi l b lnh.

Hnh 1.16: Vic kt ni cp nhit in vi s b ngui2.1.2 Resistance Temprature Detectors (RTDs)Nhit in tr RTDs l loi cm bin nhit thng c ch to bng kim loi nguyn cht (hoc pha tp nh) m in tr ca n tng khi nhit tng (nhit in tr dng). Hu ht RTDs c ch to dng vng dy hoc cc ming film kim loi.So vi Thermocouple v Thermistors th RTDs l cm bin nhit c tuyn tnh trong di nhit rng hn v cho chnh xc cao hn.Cc loi RTD

Cc dng mch o ca RTDMch o 2 dy

RTD l thit b in tr th ng nn n yu cu 1 dng in kch thch v RTD c kch thch vi ngun dng IEX.in tr 2 u dy gia thit b o v RTD s gy ra in p ri trn mi u l IEX.RL (volt).in p ri trn u dy vi in p ri trn RTD dn n kt qu c th sai s ng k trong tnh ton nhit .Mch o 2 dy cho kt qu sai s ln.Mch o 4 dy

Mch o 4 dy l mch o tt hn so vi 2 dy v c th kt ni dy di.RTD c kt ni chung 4 u: 2 u dng cung cp ngun kch thch cho thit b, 2 u in p dng o.Vi kt ni ny s loi tr c in p ri gy ra bi dng kch qua in tr u dy (RL1.RL4) v dng chy khng ng k trong 2 in tr (RL2.RL3), ch ri qua in tr RT lm cho php o chnh xc hn.Mch o 3 dy

gim chi ph c th loi b 1 dy, mch 4 dy tr thnh mch 3 dy, sai s ch cn RL1 v RT ca RTD.Bng in tr / Nhit Bng ** i vi Platinum 385, 100 0 C

Kt qu tuyn tnh ha chy bng MATLABM chng trnh MATLAB%Linearclc; clear all;kx=-1:0.1:1;vb=1.2;vob=zeros(5,21);gama=[1 2 5 10 20];A=1; for i=1:1:5 for j=1:1:21 beta=(1+gama(i))/(gama(i)*A); vob(i,j)=vb*A*kx(j)*((gama(i))/(1+gama(i))^2); endendplot(kx,vob(1,:),'--.c',kx,vob(2,:),'--*r',kx,vob(3,:),'--.k',kx,vob(4,:),'-..',kx,vob(5,:),'-..')xlabel('Input Kx')ylabel('Output(V)')axis([-1 1 -0.4 0.4])grid on

Kt qu chng trnh chy bng MATLAB2.1.3 Thermistorsin tr nhit l mt loi cm bin nhit vi gi thnh r, l cc in tr nhit bn dn c ch to t cc oxides ca mt s kim loi nh (Mangan, Nickel, cobalt,v.v). chnh xc ca Thermistors ln hn khong 10 ln so vi Thermocouple nhng khng chnh xc bng RTDs Thermistors thng c dng trong khong nhit t -80 C. 250 C, c tuyn ca loi cm bin nhit ny c phi tuyn cao.2.2 Cm bin o lc (Strain gauge)Cm bin o lc c s dng rng ri trong vic o lng lc hoc c th hn l s bin dng do tc ng ca lc. Cm bin lc vi cc phn t in tr c gn c nh l dng thng gp, n bao gm vt liu in tr (thng dng film mng micromet) c gn ln mt b mt polyester.

Cc thng s c bn: di bin dng: H s bin dng: H s GF ca kim loi l 2H s bin dng GF c cung cp bi nh sn xut cho tng cm bin c th.Thng thng h s ny nm trong khong t 2-4 cho cc cm bin c in tr 120 Ohm, 350 Ohm v 1 Kohm.V d: Nu mt cm bin lc vi in tr danh nh l 350 Ohm v h s bin dng GF l 2.0 b bin dng 1% th in tr ca n s thay i 2% hay 0.57Ohm.V nhy nn mch cu Wheatstone thng c s dng cho cc php o m trong c s thay i rt nh v in tr, c th l cm bin o lc. Mch cu Wheatstone bao gm 4 phn t in tr v c th c kch thch bi mt ngun in p/dng in.Mch cu Wheatstone c bn nh biu din bn di.

Hnh 1.17: Mch cu Wheatstone c bnMch cu

Mch cu

Mch cu ton phn

Chng 2THIT K H THNG THU THP D LIU V IU KHIN NHIT , M TRONG PHNG NH N2.1 Gii thiu h thng nh nH thng c thit k cho phng nh n nhm to ra mi trng thun li cho cy xanh, khc hn vi mi trng khc nghit bn ngoi, tuy nhin khng tch khi s nh hng ca mi trng bn ngoi:1. My lnh2. Qut ht3. Vi phun sng4. n5.Tm lp Polycarbonat6. Xp 7. Cy ging8. Cc nng my lnh

Hnh 2.1 H thng nh nTrong : My lnh: lm gim nhit v lm mt phng nh n. Qut: lm mt phng v to i lu n nh nhit trong phng. Phun sng: lm mt v tng m thch hp cho cy pht trin. n: to nh sng cho cy quang hp v tng nhit lm kh phng lc m cao. Tm lp Polycarbonat: gim bc x nh nng mt tri chiu trc tip vo cy ging. Xp: to vch ngn gia mi trng bn ngoi v bn trong phng nh n.

2.2 S khi h thng

Hnh 2.2 S khi h thngSTTCH THCH

1Mn hnh HMI hin th,iu khin thng s nhit , m

2B vi iu khin PIC16F877A x l tn hiu t cm bin

3B ngun: Cp ngun cho h thng

4My tnh: iu khin h thng thng qua giao din Citect

5Cm bin: Thu nhn cc cc gi tr nhit , m

6PLC b x l trung tm

7C cu chp hnh: Cc ng c iu khin cc thit b nhm thay i yu t nhit , m ( Qut, phung sng, my lnh)

2.3 Cc khi chc nng trong h thng2.3.1 Cm bin:

Hnh 2.3 Cm bin nhit , m SHT75Cm bin SHT75 l loi cm bin tch hp nhit v m do Sensirison sn xut.Mt b cm bin in dung duy nht cc phn t c s dng o m tng i trong khi nhit c o bi mt cm bin khong cch bng tn.

Hnh 2.4 S khi SHT75Tnh hiu Analog t hai cm bin qua khu khuych i a vo b chuyn i analog 14 chuyn i thnh tn hiu s vi mt giao din kt ni. Kt qu l cht lng tn hiu c tt hn thi gian p ng nhanh chng hn.Bng c tnh ca cm ca cm c th hin theo bng i km sau:

Hnh 2.5 Cc c tnh ca cm bin SHT75Cm bin c kt ni vi vi iu khin Pic16f877a theo chun truyn thng sau:

Hnh 2.6 Chun truyn thng gia SHT75 v PIC16f877a2.3.2 Vi iu khin PIC1f877a C nhim v c gi tr cm bin lu tr d liu sau truyn thng qua PLC theo chun RS485

Hnh 2.7 Vi iu khin PIC 16f877aBng 2.1: c tnh k thut ca PIC6F877Ac imPIC16F877A

Tn s lm vicDC 20 MHz

Reset (and delays)POR, BOR(PWRT, OST)

Flash program memory (14 bit-word)8K

Data memory368

Eeprom data memory (bytes)256

Interrupts15

I/O PortsPorts A, B, C, D, E

Timers3

Capture/Compare/PWM modules2

Serial CommunicationsMSSP, USART

Parallel CommunicationsPSP

10-bit Analog-to-Digital Module8 input channels

Analog Comparators2

Instruction Set35 Instructions

Packages40-pin PDIP

2.3.4B x l trung tm: PLC S7-200 (CPU 224)Dng PLC S7-224XP vi 2 cng Freeport mt s dng gio tip vi PIC 16f877A mt giao tip vi mn hnh HMI.

Hnh 2.8 PLC S7-200 (CPU 224)2.3.5 Cng truyn thng PC/PPI: S7-200 dng cng truyn thng ni tip RS485 phc v cho vic ghp ni vi thit b lp trnh hoc vi trm PLC khc.

Hnh 2.9: S chn cng truyn thngBng 2.3: Chc nng chn kt ni PLCChn Gii thch

1 t

2 24 VDC

3 Truyn v nhn d liu

4 Khng s dng

5 t

6 5 VDC(in tr trong 100)

7 24 VDC (120mA ti a)

8 Truyn v nhn d liu

9 Khng s dng

Hnh 2.9 Giao tip PC vi S7 qua cng truyn thng2.3.6. Mn hnh hin th HMI

Bng 2.4: Thng s k thut ca mn hnh iu khin, gim st HMIHin th Kch thc 5,7 115,2 inch (W) x 86,4 (H)

Mn hnhMu TFT

Mu sc hin thi256 Colours 256 Mu sc

phn gii320 x 240 pixels

n nnNgi dng c th thay th CCFL

Touch Panel LoiPhim in tr (analog)

Touch Panel Ngh quyt1024x1024

ng dng b nh2MB FLASH EPROM

B nh sao lu d liu256KB

Giao din ni tip1

Com 1RS232/RS422

Com 2Khng c

Chc nng iu khin PLCKhng c

CF-Card I / FC

Ethernet I / FKhng c

USB I / Fkhng c

in pDC24V

nh giIP65

Nhit hot ng0 C n 50 C

Bn ngoi Kch thc (WxHxD trong mm)171mm [6.73in.] X 138mm [5.43in.] X 60mm [2.36in.]

Cut-out Kch thc (wxh trong mm)156mm x 123.5mm

Lp trnh phn mmGP-Pro PBIII

2.3 Gii thut iu khin ht thng nh n:Hnh 2.10 Lu gii thut iu khin ht thngTrong : T : Nhit bn trong phng nh n. T1