Plc Hung Yen

8/3/2019 Plc Hung Yen

1/137

Lp trnh PLC

Bi:Khoa CNTT HSP KT Hng Yn


2/137


3/137

Lp trnh PLC

Bi:Khoa CNTT HSP KT Hng Yn

Phin bn trc tuyn:< http://voer.edu.vn/content/col10164/1.1/>

Hoc lieu Mo Vietnam - Vietnam Open Educational Resources


4/137

Ti liu ny v s bin tp ni dung c bn quyn thuc v Khoa CNTT HSP KT Hng Yn. Ti liu ny tun thgiy php Creative Commons Attribution 3.0 (http://creativecommons.org/licenses/by/3.0/).Ti liu c hiu nh bi: July 30, 2010Ngy to PDF: July 30, 2010 bit thng tin v ng gp cho cc module c trong ti liu ny, xem tr. 127.


5/137

Ni dung

1 Chng 1: Tng quan v PLC

1.1 M U . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 Lch s pht trin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.3 Cu trc v nguyn l lm vic ca PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.4 Phn loi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.5 Cu trc phn cng PLC S7-300 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2 Chng 2 : Ngn ng lp trnh v ng dng

2.1 Gii thiu cc ngn ng lp trnh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452.2 Chu trnh lm vic, lp trnh v cu trc chng trnh . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . 472.3 Tp lnh PLC S7 - 300 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

3 Chng 3 : Ngn ng lp trinh Step 7

3.1 CI T STEP 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 953.2 Son tho mt Project mi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 963.3 Son tho chng trnh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1043.4 Chy th, np chng trnh xung phn cng, gim st hot ng ca chng

trnh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1194 Chng 4 : La chn, lp t, kim tra v bo tr h thng

4.1 La chn, lp t, kim tra v bo tr h thng .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123Attributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 7


6/137

iv


7/137

Chng 1

Chng 1: Tng quan v PLC

1.1 M U1

Trong cc h thng sn xut, trong cc thit b t ng v bn t ng, h thng iu khin ng vai triu phi ton b cc hot ng ca my mc thit b. Cc h thng my mc v thit b sn xut thngrt phc tp, c rt nhiu i lng vt l phi iu khin c th hot ng ng b hoc theo mt trnht cng ngh nht nh nhm to ra mt sn phm mong mun. Tng i lng vt l n l c th ciu khin bng mt mch iu khin c s dng tng t hay gin on. iu khin nhiu i lng vtl ng thi chng ta khng th dng cc mch iu khin tng t m phi s dng h thng iu khinl gc. Trc y cc h thng iu khin l gc c s dng l h thng l gc r le. Nh s pht trinnhanh chng ca k thut in t, cc thit b iu khin l gc kh lp trnh PLC (Programmable LogicController) xut hin vo nm 1969 thay th cc h thng iu khin r le. Cng ngy PLC cng tr nnhon thin v a nng. Cc PLC ngy nay khng nhng c kh nng thay th hon ton cc thit b iukhin lo gc c in, m cn c kh nng thay th cc thit b iu khin tng t. Cc PLC c s dngrng ri trong cng nghip.

Chc nng chnh ca PLC l kim tra trng thi ca cc u vo v iu khin cc qu trnh hoc cch thng my mc thng qua cc tn hiu trn chnh u ra ca PLC. T hp l gc ca cc u vo tora mt hay nhiu tn hiu ra c gi l iu khin l gc. Cc t hp l gc thng c thc hin theotrnh t iu khin hay cn gi l chng trnh iu khin. Chng trnh iu khin c lu trong b nhca PLC c th bng cch lp trnh bng thit b cm tay ni trc tip vi PLC hoc lp trnh trn mytnh c nhn nh cc phn mm chuyn dng v truyn vo PLC qua mng hay qua cp truyn d liu. Bx l tn hiu, thng l cc b vi x l tc cao, thc hin chng trnh iu khin theo chu k. Khongthi gian thc hin mt chu trnh iu khin t lc kim tra cc tn hiu vo, thc hin cc php tnh lo gchoc i s c c tn hiu iu khin, cho n khi pht tn hiu n u ra c goi l chu k thi gianqut.

1This content is available online at .

1


8/137

2 CHNG 1. CHNG 1: TNG QUAN V PLC

Figure 1.1

PLC trong cng nghip thng c cu hnh n gin nht, bi v cc chng trnh trnh iu khin qutrnh cng ngh hay my mc thng c hot ng 24/24 v khng cn bt c s can thip ca con ngitrong qu trnh iu khin. PLC ch dng qut chng trnh iu khin khi ngt ngun hoc khi cng tcngng c kch hot. S khi n gin ho ca PLC c th hin trn hnh

Trn u vo ca PLC c th c cc knh tn hiu tng t hoc cc knh tn hiu s. Cc knh tn hiuny xut pht t cc cm bin, t cc cng tc hnh trnh, cng tc ng ngt mch in hoc t cc bin

l gc tng ng vi cc cc trng thi ca my mc, thit b. Tn hiu vo c b x l trung tm x lnh cc php tnh l gc hay s hc v kt qu l cc tn hiu ra. Cc tn hiu tn hiu ra l cc tn hiutruyn in nng n cho cc c cu chp hnh nh cun ht, n hiu, ng c vv.

in p trn u vo ca PLC l in p cng sut thp, tng ng vi mc t 0V n 5V mt chiu.Khi ta ni cc u vo c mc in p cao hn 5V, thng phi dng cc knh c cc mch chuyn i bin in p vo thnh in p tng ng vi mc +/ 5VDC. in p trn u ra ca PLC c th cnhiu mc in p khc nhau, nhng u c mc nng lng thp. Nu cn phi iu khin c cu chphnh c mc nng lng cao hn, ta phi s dng cc thit b khuych i cng sut.

1.2 Lch s pht trin2

Vo khong nm 1968, cc nh sn xut t a ra cc yu cu k thut u tin cho thit b i khinl gc kh lp trnh. Mc ch u tin l thay th cho cc t iu khin cng knh, tiu th nhiu in nngv thng xuyn phi thay th cc r le do hng cun ht hay gy cc thanh l xo tip im. Mc ch thhai l to ra mt thiu b iu khin c tnh linh hot trong vic thay i chng trnh iu khin. Cc yucu k thut ny chnh l c s ca cc my tnh cng nghip, m u im chnh ca n l s lp trnh ddng bi cc k thut vin v cc k s sn xut. Vi thit b iu khin kh lp trnh, ngi ta c th gimthi gian dng trong sn xut, m rng kh nng hon thin h thng sn xut v thch ng vi s thay itrong sn xut. Mt s nh sn xut thit b iu khin trn c s my tnh sn xut ra cc thit b iukhin kh lp trnh cn gi l PLC.



9/137

3

Nhng PLC u tin c ng dng trong cng nghip t vo nm 1969 em li s u vit hnhn cc h thng iu khin trn c s r le. Cc thit b ny c lp trnh d dng, khng chim nhiukhng gian trong cc xng sn xut v c tin cy cao hn cc h thng r le. Cc ng dng ca PLC nhanh chng rng m ra tt c cc ngnh cng nghip sn xut khc.

Hai c im chnh dn n s thnh cng ca PLC chnh l tin cy cao v kh nng lp trnh ddng. tin cy ca PLC c m bo bi cc mch bn dn c thit k thch ng vi mi trng cngnghip. Cc mch vo ra c thit k m bo kh nng chng nhiu, chu c m, chu c du, bi vnhit cao. Cc ngn ng lp trnh u tin ca PLC tng t nh s thang trong cc h thng iukhin l gc, nn cc k s lm quen vi s thang, d dng thch nghi vi vic lp trnh m khng cnphi qua mt qu trnh o to no. Mt s cc ng dng ca my tnh trong sn xut trong thi gian ub tht bi, cng chnh v vic hc s dng cc phn mm my tnh khng d dng ngay c vi cc k s.

Khi cc vi x l c a vo s dng trong nhng nm 1974 1975, cc kh nng c bn ca PLCc m rng v hon thin hn. Cc PLC c trang b vi x l c kh nng thc hin cc tnh ton v xl s liu phc tp, iu ny lm tng kh nng ng dng ca PLC cho cc h thng iu khin phc tp.Cc PLC khng ch dng li ch l cc thit b iu khin l gc, m n cn c kh nng thay th c ccthit b iu khin tng t. Vo cui nhng nm by mi vic truyn d liu tr nn d dng nh s

pht trin nhy vt ca cng nghip in t. Cc PLC c th iu khin cc thit b cch xa hng vi trmmt. Cc PLC c th trao i d liu cho nhau v vic iu khin qu trnh sn xut tr nn d dng hn.Thit b iu khin kh lp trnh PLC chnh l cc my tnh cng nghip dng cho mc ch iu khin

my, iu khin cc ng dng cng nghip thay th cho cc thit b cng nh cc r le, cun ht v cctip im.

Ngy nay chng ta c th thy PLC trong hng nghn ng dng cng nghip. Chng c s dng trongcng nghip ho cht, cng nghip ch bin du, cng nghip thc phm, cng nghip c kh, cng nghipx l nc v cht thi, cng nghip dc phm, cng nghip dt may, nh my in ht nhn, trong cngnghip khai khong, trong giao thng vn ti, trong qun s, trong cc h thng m bo an ton, trong cch thng vn chuyn t ng, iu khin r bt, iu khin my cng c CNC vv. Cc PLC c th c ktni vi cc my tnh truyn, thu thp v lu tr s liu bao gm c qu trnh iu khin bng thng k,qu trnh m bo cht lng, chn on s c trc tuyn, thay i chng trnh iu khin t xa. Ngoi raPLC cn c dng trong h thng qun l nng lng nhm gim gi thnh v ci thin mi trng iu

khin trong cc cc h thng phc v sn xut, trong cc dch v v cc vn phng cng s.S ra i ca my tnh c nhn PC trong nhng nm tm mi nng cao ng k tnh nng v khnng s dng ca PLC trong iu khin my v qu trnh sn xut. Cc PC gi thnh khng cao c th sdng nh cc thit b lp trnh v l giao din gia ngi vn hnh v h thng iu khin. Nh s phttrin ca cc phn mm ho cho my tnh c nhn PC, cc PLC cng c trang b cc giao din ho c th m phng hoc hin th cc hot ng ca tng b phn trong h thng iu khin. iu ny c ngha c bit quan trng i vi cc my CNC, v n to cho ta kh nng m phng trc qu trnh giacng, nhm trnh cc s c do lp trnh sai. My tnh c nhn PC v PLC u c s dng rng ri trongcc h thng iu khin sn xut v c trong cc h thng dch v.

PLC c sn xut bi nhiu hng khc nhau trn th gii. V nguyn l hot ng, cc PLC ny ctnh nng tng t ging nhau, nhng v lp trnh s dng th chng hon ton khc nhau do thit k khcnhau ca mi nh sn xut. PLC khc vi cc my tnh l khng c ngn ng lp trnh chung v khngc h iu hnh. Khi c bt ln th PLC ch chy chng trnh iu khin ghi trong b nh ca n, ch

khng th chy c hot ng no khc. Mt s hng sn xut PLC ln c tn tui nh: Siemens, Toshiba,Mishubisi, Omron, Allan Bradley, Rocwell, Fanuc l cc hng chim phn ln th phn PLC th gii. CcPLC ca cc hng ny c ng dng rng ri trong cng nghip s dng cng ngh t ng ho.

Cc thit b iu khin PLC to thm sc mnh, tc v tnh linh hot cho cc h thng cng nghip.Bng s thay th cc phn t c in bng PLC, qu trnh iu khin tr nn nhanh hn, r hn, v quantrng nht l hiu qu hn. PLC l s la chn tt hn cc h thng r le hay my tnh tiu chun do mts l do sau:

-Tn t khng gian: Mt PLC cn t khng gian hn mt my tnh tiu chun hay t iu khin r le thc hin cng mt cc nng.


10/137


- Tit kim nng lng: PLC tiu th nng lng mc rt thp, t hn c cc my tnh thng thng.-Gi thnh thp : Mt PLC gi tng ng c 5 n 10 r le, nhng n c kh nng thay th hng

trm r le.- Kh nng thch ng vi mi trng cng nghip: Cc v ca PLC c lm t cc vt liu cng, c

kh nng chng chu c bi bn, du m, m, rung ng v nhiu. Cc my tnh tiu chun khng ckh nng ny.

- Giao din tc tip: Cc my tnh tiu chun cn c mt h thng phc tp c th giao tip vi mitrng cng nghip. Trong khi cc PLC c th giao din trc tip nh cc m un vo ra I/O.

- Lp trnh d dng: Phn ln cc PLC s dng ngn ng lp trnh l s thang, tng t nh s u ca cc h thng iu khin r le thng thng.

- Tnh linh hot cao: Chng trnh iu khin ca PLC c th thay i nhanh chng v d dng bngcch np li chng trnh iu khin mi vo PLC bng b lp trnh, bng th nh, bng truyn ti quamng.

1.3 Cu trc v nguyn l lm vic ca PLC3

1.3.1 Cu trc chungPLC l thit b iu khin logic kh trnh (Program Logic Control), l loi thit b cho php thc hin linhhot cc thut ton iu khin s thng qua 1 ngn ng lp trnh, thay cho vic phi th hin thut ton bng mch s.

Cng nh cc thit b lp trnh khc, h thng lp trnh c bn ca PLC bao gm 2 phn: khi x ltrung tm (CPU) v h thng giao tip vo/ra (I/O) nh s khi:

Figure 1.2



11/137

5

1.3.1.1 Khi x l trung tm:

L mt vi x l iu khin tt c cc hot ng ca PLC nh: Thc hin chng trnh, x l vo/ra vtruyn thng vi cc thit b bn ngoi.

1.3.1.2 B nh

C nhiu cc b nh khc nhau dng cha chng trnh h thng l mt phn mm iu khin cc hotng ca h thng, s LAD, tr s ca Timer, Counter c cha trong vng nh ng dng, ty theoyu cu ca ngi dng c th chn cc b nh khc nhau:

1. B nh ROM: l loi b nh khng thay i c, b nh ny ch np c mt ln nn t c sdng ph bin nh cc loi b nh khc.

2. B nh RAM: l loi b nh c th thay i c v dng cha cc chng trnh ng dng cngnh d liu, d liu cha trong Ram s b mt khi mt in. Tuy nhin, iu ny c th khc phc bngcch dng Pin.

3. B nh EPROM: Ging nh ROM, ngun nui cho EPROM khng cn dng Pin, tuy nhin ni dungcha trong n c th xo bng cch chiu tia cc tm vo mt ca s nh trn EPROM v sau np li

ni dung bng my np.4. B nh EEPROM: kt hp hai u im ca RAM v EPROM, loi ny c th xa v np bng tnhiu in. Tuy nhin s ln np cng c gii hn.

Mt PLC c y cc chc nng nh: b m, b nh thi, cc thanh ghi (registers) v tp lnh chophp thc hin cc yu cu iu khin phc tp khc nhau. Hot ng ca PLC hon ton ph thuc vochng trnh nm trong b nh, n lun cp nht tn hiu ng vo, x l tn hiu iu khin ng ra.

nh gi mt b PLC ngi ta da vo 2 tiu chun chnh: Dung lng b nh v s tip im vo/raca n. Bn cnh cng cn ch n cc chc nng nh: B vi x l, chu k xung clock, ngn ng lptrnh, kh nng m rng s cng vo/ra.

Bn cnh , mt b PLC hon chnh cn i km thm mt n v lp trnh bng tay hay bng mytnh. Hu ht cc n v lp trnh n gin u c RAM cha ng chng trnh di dng honthin hay b sung. Nu n v lp trnh l n v xch tay, RAM thng l loi CMOS c pin d phng,ch khi no chng trnh c kim tra v sn sng s dng th n mi truyn sang b nh PLC. i vi

cc PLC ln thng lp trnh trn my tnh nhm h tr cho vic vit, c v kim tra chng trnh. Ccn v lp trnh ni vi PLC qua cng RS232, RS422, RS458, . . .Trong h thng iu khin PLC cc phn t nhp tn hiu nh: chuyn mch, nt n, cm bin, ... c

ni vi u vo ca thit b PLC. Cc phn t chp hnh nh: n bo, r le, cng tc t,... c ni nli ra ca PLC ti cc u ni.

Chng trnh iu khin PLC c son tho di cc dng c bn (s c trnh by phn sau) sc np vo b nh bn trong PLC, sau t ng thc hin tun t theo mt chui lnh iu khin cxc nh trc.

H cn cho php cng nhn vn hnh thao tc bng tay cc tip im, nt dng khn cp m botnh an ton trong cc trng hp xy ra s c.

PLC c xem nh tri tim trong mt h thng iu khin t ng n l vi chng trnh iu khinc cha trong b nh ca PLC, PLC thng xuyn kim tra trng thi ca h thng thng qua cc tnhiu hi tip t thit b vo t c th a ra nhng tn hiu iu khin tng ng n cc thit b ra.

PLC c th c s dng cho nhng yu cu iu khin n gin v c lp i lp li theo chu k, hoclin kt vi my tnh ch khc hoc my tnh ch thng qua mt kiu h thng mng truyn thng thchin cc qu trnh x l phc tp.

1.3.1.3 Tn hiu vo

Mc thng minh ca mt h thng iu khin ph thuc ch yu vo kh nng ca PLC c ccc d liu khc nhau t cc cm bin cng nh bng cc thit b nhp bng tay.

Tiu biu cho cc thit b nhp bng tay nh: nt n, bn phm v chuyn mch. Mt khc, o, kimtra chuyn ng, p sut, lu lng cht lng ,... PLC phi nhn cc tn hiu t cc cm bin. V d: tip


12/137


im hnh trnh, cm bin quang in,...tn hiu a vo PLC c th l tn hiu s (digital) hoc tn hiutng t (analog), cc tn hiu ny c giao tip vi PLC thng qua cc modul nhn tn hiu vo khcnhau khc nhau DI (Digital Input) hoc AI (Analog Input),....

1.3.1.4 i tng iu khin

Mt h thng iu khin s khng c ngha thc t nu khng giao tip c vi thit b ngoi, cc thitb ngoi thng dng nh: mt, van, rle, n bo, chung in,...cng ging nh thit b vo, cc thit bngoi c ni n cc cng ra ca modul ra (output). Cc modul ra ny c th l DO (Digital Output)hoc AO (ra tng t).

1.3.2 Nguyn l lm vicCPU iu khin cc hot ng bn trong PLC. B x l s c v kim tra chng trnh c cha trongb nh, sau s thc hin th t tng lnh trong chng trnh, s ng hay ngt cc u ra. Cc trngthi ng ra y c pht ti cc thit b lin kt thc thi. V ton b cc hot ng thc thi u phthuc vo chng trnh iu khin c gi trong b nh.

PLC thc cht chy bng m my vi h thng s nh phn, do tc qut vng chng trnh c tht n vi phn ngn giy, cc Software dng lp trnh PLC tch hp c phn bin dch. Cc dng lnhkhi lp trnh chng ta a t chng trnh vo th trnh bin dch s chuyn i sang m my v ghi tngbit 0 hay bit 1 ln ng vo v tr c a ch c quy c trc trong PLC ln PC c thc thi xyra ngc li v trnh bin dch lm xong nhim v ca mnh trc khi tr chng trnh ln Monitor..

H thng Bus l tuyn dng truyn tn hiu, h thng gm nhiu ng tn hiu song song:- Address Bus: Bus a ch dng truyn a ch n cc Modul khc nhau.- Data Bus: Bus dng truyn d liu.- Control Bus: Bus iu khin dng truyn cc tn hiu nh th v iu khin ng b cc hot ng

trong PLC.Trong PLC cc s liu c trao i gia b vi x l v cc modul vo ra thng qua Data Bus. Address

Bus v Data Bus gm 8 ng, cng thi im cho php truyn 8 bit ca 1 byte mt cch ng thi haysong song.

Nu mt modul u vo nhn c a ch ca n trn Address Bus, n s chuyn tt c trng thi uvo ca n vo Data Bus. Nu mt a ch byte ca 8 u ra xut hin trn Address Bus, modul u ratng ng s nhn c d liu t Data bus. Control Bus s chuyn cc tn hiu iu khin vo theo dichu trnh hot ng ca PLC. Cc a ch v s liu c chuyn ln cc Bus tng ng trong mt thi gianhn ch.

H thng Bus s lm nhim v trao i thng tin gia CPU, b nh v I/O. Bn cch , CPU ccung cp mt xung Clock c tn s t 18 MHZ. Xung ny quyt nh tc hot ng ca PLC v cungcp cc yu t v nhthi, ng h ca h thng.

* Vng qut ca chng trnh:PLC thc hin cc cng vic (bao gm c chng trnh iu khin) theo chu trnh lp. Mi vng lp c

gi l mt vng qut (scancycle). Mi vng qut c bt u bng vic chuyn d liu t cc cng vo sti vng b m o I, tip theo l giai on thc hin chng trnh. Trong tng vng qut, chng trnh

c thc hin t lnh u tin n lnh kt thc ca khi OB1.Sau giai on thc hin chng trnh l giai on chuyn cc ni dung ca b m o Q ti cc cng ras. Vng qut c kt thc bng giai on x l cc yu cu truyn thng (nu c) v kim tra trng thica CPU. Mi vng qut c th m t nh sau:


13/137

7

Figure 1.3

Ch : B m I v Q khng lin quan ti cc cng vo/ra tng t nn cc lnh truy nhp cng tngt c thc hin trc tip vi cng vt l ch khng thng qua b m.

Thi gian cn thit cho PLC thc hin c mt vng qut c gi l thi gian vng qut (Scantime). Thi gian vng qut khng c nh, tc l khng phi vng qut no cng c thc hin trong mtkhong thi gian nh nhau. C vng qut c thc hin lu, c vng qut c thc hin nhanh tuthucvo s lnh trong chng trnh c thc hin, vo khi lng d liu truyn thng. Trong vng qut .Nh vy gia vic c d liu t i tng x l, tnh ton v vic gi tn hiu iu khin n i tngc mt khongthi gian tr ng bng thi gian vng qut. Ni cch khc, thi gian vng qut quyt nhtnh thi gian thc ca chng trnh iu khin trong PLC. Thi gian vng qut cng ngn, tnh thi gianthc ca chng trnh cng cao.

Nu s dng cc khi chng trnh c bit c ch ngt, v d khi OB40, OB80,... Chng trnh cacc khi s c thc hin trong vng qut khi xut hin tn hiu bo ngt cng chng loi. Cc khichng trnh ny c th thc hin ti mi vng qut ch khng phi b g p l phi trong giai on thchin chng trnh. Chng hn mt tn hiu bo ngt xut hin khi PLC ang giai on truyn thng vkim tra ni b, PLC s tm dng cng vic truyn thng, kim tra, thc hin ngt nh vy, thi gian

vng qut s cng ln khi cng c nhiu tn hiu ngt xut hin trong vng qut. Do nng cao tnhthi gian thc cho chng trnh iu khin, tuyt i khng nnvit chng trnh x l ngt qu di hocqu lm dng vic s dng ch ngt trong chng trnh iu khin.

Ti thi im thc hin lnh vo/ra, thng thng lnh khng lm vic trc tip vi cng vo/ra m chthng qua b nh m ca cng trong vng nh tham s. Vic truyn thng gia b m o vi ngoi vitrong giai on 1 v 3 do h iu hnh CPU qun l. mt s modul CPU, khi gp lnh vo/ra ngay lptc h thng s cho dng mi cng vic khc, ngay c chng trnh x l ngt, thc hin vi cng vo/ra.


14/137


1.3.3 u nhc im ca PLC trong cng nghip1.3.3.1 c im h thng iu khin dng Rle

- Tn km rt nhiu dy dn .- Thay th rt phc tp.- Cn cng nhn sa cha tay ngh cao.- Cng sut tiu th ln .- Thi gian sa cha lu.- Kh cp nht s nn gy kh khn cho cng tc bo tr cng nh thayth.Tm li: nhng h thng relay c iu khin ng ngt mt thit b sau khi thc thi tc v theo mt

khong thi gian xc nh, chng ta hay dng cc b Timer Controller, khi m cc s kin, sn phm, . . .chng ta dng cc b Counter Controller c th l bng s c kh hay hin th bng Led 7 on, LCD . . . ccgi tr ci t c thao tc trn cc b controller ny, nhng vn s bt u phc tp dn khi trong hthng cn nhiu b timer hay counter ring l nhng phi phi hp c h thng trong mt tc v lin tcv khng c tnh lp li, lc ny t iu khin ca ta bt u qu ti v s lng controller, dy ni iu

khin, cable ngun bt u tng ln v khi h thng cn s thay i cc tham s trong qu trnh iu khinchng ta s tn rt nhiu cng sc ln lt thit lp tng b Timer hay Counter. Qu phc tp. Chngta cha tnh n kh nng lo ho cc thit b, tnh chnh xc s t t km i theo thi gian, cha tnh nkh nng h hng tc thi ca s lng thit b ny s tiu tn ca chng ta kh nhiu tin chi cho vicchun on v thay th v chng ta cn cha tnh n s thi gian v ch khi ngng h thng khng vnhnh sn xut c, c l cc s kin nu trn hon ton ng vi cng thc: Xc sut ca s ln hng hcs tng t l thun vi tng s cc thit b c tham gia trong qu trnh iu khin.

1.3.3.2 c im h thng iu khin dng PLC

S ra i ca h iu khin PLC lm thay i hn h thng iu khin cng nh cc quan nim thit kv chng, h iu khin dng PLC c nhiu u im nh sau:

- Gim 80% s lng dy ni.

- Cng sut tiu th ca PLC rt thp .- C chc nng t chun on do gip cho cng tc sa cha c nhanh chng v d dng.- Chc nng iu khin thay i d dng bng thit b lp trnh (my tnh, mn hnh) m khng cn

thay i phn cng nu khng c yu cu thm bt cc thit b vo, ra.- S lng rle v timer t hn nhiu so vi h iu khin c in.- S lng tip im trong chng trnh s dng khng hn ch.- Thi gian hon thnh mt chu trnh iu khin rt nhanh (vi ms) dn n tng cao tc sn xut .- Chng trnh iu khin c th in ra giy ch trong vi pht gip thun tin cho vn bo tr v sa

cha h thng.- Lp trnh d dng, ngn ng lp trnh d hc.- Gn nh, d dng bo qun, sa cha.- Dung lng b nh ln c th cha c nhng chng trnh phc tp.- Hon ton tin cy trong mi trng cng nghip.

- Giao tip c vi cc thit b thng minh khc nh: my tnh, ni mng, cc Modul m rng.- tin cy cao, kch thc nh.- Gi c c th cnh tranh c.c trng ca PLC l kh nng c th lp trnh c, ch s IP di quy nh cho php PLC hot ng

trong mi trng khc nghit cng nghip, yu t bn vng thch nghi, tin cy, t l h hng rt thp,thay th v hiu chnh chng trnh d dng, kh nng nng cp cc thit b ngoi vi hay m rng s lngu vo nhp v u ra xut c p ng tu nghi trong kh nng trn c th xem l cc tiu ch u tincho chng ta khi ngh n thit k phn iu khin trung tm cho mt h thng hot ng t ng.


15/137

9

1.3.4 ng dng ca PLC trong cng nghipT cc u im nu trn, hin nay PLC c ng dng trong rt nhiu lnh vc khc nhau trong cngnghip nh:

- H thng nng vn chuyn.- Dy chuyn ng gi.- Cc robot lp gip sn phm .- iu khin bm.- Dy chuyn x l ho hc.- Cng ngh sn xut giy .- Dy chuyn sn xut thu tinh.- Sn xut xi mng.- Cng ngh ch bin thc phm.- Dy chuyn ch to linh kin bn dn.- Dy chuyn lp gip Tivi.- iu khin h thng n giao thng.- Qun l t ng bi u xe.- H thng bo ng.- Dy chuyn may cng nghip.- iu khin thang my.- Dy chuyn sn xut xe t.- Sn xut vi mch.- Kim tra qu trnh sn xut .

1.4 Phn loi4

1.4.1 V hnh dngC hai kiu c cu thng dng vi cc h thng PLC l kiu hp n v kiu modul ni ghp. Kiu hp n

thng c s dng cho cc thit b iu khin lp trnh c nh v c cung cp di dng nguyn chichon chnh.Kiu modul ghp ni: gm nhiu modul ring cho b ngun, CPU, cng vo/ra.... c lp trn thanh

ray. Kiu ny c th s dng cho cc thit b lp trnh mi kch c.

1.4.2 V s lng cc u vo/raCn c vo s lng cc u vo/ ra, ta c th phn PLC thnh bn loi sau:

- Micro PLC l loi c di 32 knh vo/ ra- PLC nh c n 256 knh vo/ ra- PLC trung bnh c n 1024 knh vo/ ra- PLC c ln c trn 1024 knh vo/ra.



16/137


Figure 1.4

Cc micro PLC thng c t hn 32 u vo/ra. Trn hnh 1.2 l v d v micro PLC h T100MD-1616do hng Triangle Research International sn xut. Cu to tng i n gin v ton b cc b phn ctch hp trn mt bng mch c kch thc nh gn. Micro PLC c cu to gm tt c cc b phn nhb x l tn hiu, b ngun, cc knh vo/ra trong mt khi. Cc Micro PLC c u im hn cc PLCnh l gi thnh r, d lp t.

Mt loi micro PLC khc l DL05 ca hng Koyo, loi ny c 30 knh vo/ ra

Figure 1.5

Mt loi micro-PLC khc l loi x ri 90 ca Fanuc. Loi ny c 8 knh vo v 8 knh ra.


17/137

11

Figure 1.6

PLC loi nh c th c n 256 u vo/ra. Trn hnh 1.5 l PLC ca hng OMRON loi ZEN 10C.Loi PLC ny c 34 knh vo/ ra gm: 6 knh vo v 4 knh ra trn m un CPU, cn li 3 m un vo/ra, vi 4 knh vo v 4 knh ra cho mi m un.


18/137


Figure 1.7

Hng Siemens c cc PLC loi nh nh S5-90U, S5-95U, S5-100U (hnh 1.6), S7 200 l cc loi PLCloi nh, c s lng knh vo/ ra nh hn 256. Cu to ca cc PLC loi nh cng tng t nh cu toca cc PLC loi trung bnh, v u l dng m un. im khc bit l dung lng b nh, s lng knhvo/ ra ca cc m un khc nhau v ln v tc x l thng tin cng khc nhau. PLC ca Siemensc dng rng ri trong hu ht cc nc c nn cng nghip pht trin.


19/137

13

Figure 1.8

Cc PLC trung bnh c th c dn 1024 u vo/ra. Loi CJ1M ca Omron trn hnh 1.8 c 320 knhvo/ ra.

Figure 1.9

Loi PLC CQM1 hay CQMIH ca Omron trn hnh c 512 knh vo ra


20/137


Figure 1.10

Hng Siemens c mt s x ri S7-200 l ccloi PLC hng trung bnh. S lng knh vo/ra ca S-300c th trong khong t 256 n 1024.

Cc PLC loi ln c nhiu hn 1024 u vo/ra. Loi ny c tc x l rt cao, dung lng b nhln v thng c dng trong iu khin cc h thng thit b cng ngh phc tp. Hng Omron c PLCloai CJ1 trn hnh 1.10, l loi c ti 1280 knh vo/ ra v loi CJ1H c ti 2560 knh vo/ra.

Figure 1.11


21/137

15

Hng Omron cn c loai CS1 trn hnh, l loi PLC c ln vi 5120 knh vo/ ra

Figure 1.12

Cc PLC loi ln ca Siemens l cc loi x ri S7-300, S7-400. Cc loi ny c s lng knh vo/ rart ln. Cc knh ny khng th u trc tip ln PLC m phi thng qua cc b dn knh v tch knh (demultiplexeur v multiplexeur). Trn hnh 1.12 l PLC S7400 ca Siemens. y l loi PLC mnh nhtca Siemens hin nay. Cu hnh ca PLC ny c biu din bng hnh. Cc PLC trung bnh v ln c ccm un vo/ra c th lp rp vi nhau trn cng mt gi tiu chun, cho php lp thm hoc tho btra m khng cn tt ngun. Cc PLC c kt ni vi nhau thng qua mng ETHERNET cng nghip


22/137


Figure 1.13


23/137

17

Figure 1.14


24/137


Figure 1.15

Hnh 1.13a.Cu trc ca S7-400


25/137

19

Figure 1.16

Hnh 1.14. S kt ni mng ca S7-400 trong cng nghipCc PLC loi ln thng dng iu khin mc cao. mc thp thng l cc thit b iu khin

tng t, hay thit b iu khin s vi cc PLC loi nh, hay loi trung bnh. mc thp, ch yu l ccthit b iu khin trc tip cc thit b cng ngh, cc c cu chp hnh, cc ng c, bm, van, cun ht,n hiu vv. iu khin mc cao bao gm cc iu khin lin quan n phn qun l h thng v qunl d liu ca h thng iu khin. mc ny, cc d liu c th c thu thp t cc cc thit b iu


26/137


khin mc thp hoc t bn ngoi h thng thng qua mng ni b v mng Internet. Cc d liu t ccPLC c truyn v cc my tnh trung tm lu tr v x l. Trng hp cc h thng sn xut t ngc iu khin bng thng k, y chnh l iu khin mc cao, tng ng vi cu trc qun l ca hthng. Hot ng ca h thng iu khin c iu chnh da theo kt qu phn tch, nh gi t cc dliu thng k, nh vy gip cho vic sn xut lun dng ti u nht v hiu qu nht. PLC S7-400 caSiemens l mt trong nhng loi PLC ln v rt mnh trong cc h thng iu khin sn xut qui m nhcc nh my cng nghip. Loi PLC ny c th kt ni trc tip qua mng Ethernet cng nghip vi ccthit b iu khin mc cao hn trao i d liu hoc thng cc cc cc knh giao din khc nh MPI ,PROFIBUS, EIB hay giao din AS thu thp d liu v iu khin nh hnh 1.14.

1.4.3 V hng sn xut v sn phmC nhiu hng sn xut PLC. Chng ta chn 4 hng tiu biu gm: Mitsubishi, Omron, Siemens, Teleme-canique.

CP1L - Th h Micro PLC mi cho tng laiTi a 160 I/O, RS-232 / 485 / 422- Kt ni vi mun m rng CPM1- B nh 5/10Kstep, c memory unit ngoi- Lp trnh cng USB bng CX-P V7.1- Chy m phng bng CX-Simulator

Figure 1.17

CPM1A, CPM2A - Loi Micro PLC thng dng


27/137

21

Table 1.1

CP1H - Loi Compact PLC cao cp (All-In-One)

Figure 1.18


28/137


PLC c va CJ1M

Figure 1.19

Cch th hin cc dng lnh v nguyn tc gi v thc thi chng trnh cng nh cc cng c dng g ri khi tho chng rt ging nhau c php v cch th hin.

Trn nn tng ph hp cc ng dng, tnh kinh t, tnh cnh tranh, cc nh sn xut PLC gii thiukh nhiu dng sn phm ph hp trong dy sn phm ca mnh, cc sn phm c ng dng n gin nh

(Logo-Siemens, Alpha-Mitsubishi, Zen-Omron, Smart-Telemecanique).Chng ta s quan tm ti cc h PLC c i ch vo/ra trn di 512 I/O (512 input/output) b nhchng trnh tng n 32KB hoc 64KB Step v cc thnh phn ngoi vi kt ni thm c th iu khintrong cc h thng t ng va v nh, n l, gn nh p ng hu ht cc yu cu iu khin theo ca cc nh thit k.

Mitsubishi: (Software m t GX-Developer V8.0Up) h Fx-xx ca hng tun th quy c gn a chmang tnh k tha v pht trin trong tng lai (ch ni v cc a ch cho cc cng vo/ra, v cc ng vov ra ny s c ni trc tip vi cc thit b ra lnh v chp hnh bn ngoi).

V d: dng Fx-xx c a ch ng vo InputDigital c gn theo nhm tng byte, bt u l byte 0tng ng chng ta c cc a ch: X000 n X007 (8 bit = 1 byte) hay cn gi l h c s 8.

Nh vy, nhm byte th 2 tip theo quy c gn a ch s bt u bng X010 n X017 a ch ngra c gn k hiu Y v bt u t Y000 n Y007 tun th tng t nh cch gn ng vo X

Cc a ch c gn theo quy c trn ch bao gm trong dng sn phm PLC c seri FX, cc dng saut seri A, Q-A c nng cp ln nhm 2 byte nh vy a ch


29/137

23

Figure 1.20

c gn lc ny s bt u bng X000 cho n X007, tun theo th t m ca h c s 16 . . .Tri qua hn 25 nm, t khi Mitsubishi Electric gii thiu PLC gn u tin trn th trng chu Au.

T Mitsubishi tr nn hng dn u th gii trong khu vc ny, vi hn 6 triu trong s nhng s ci

t b iu khin.Vi nhng kch thc gn ca h v chi ph thp nhng b iu khin c m ra vin cnh mi trongk thut t ng cng nghip. Nhiu ng dng cho t ng ha .

Lot FX3U m by gi ang c gii thiu l h PLCs gn v cng thnh cng ca Mitsubishi Electricth h th ba.

Tnh tng thch - nh phm vi b cp in (tip in) rng ca h nhng b iu khin FX c thc s dng khp th gii.

Tnh Ton cu - Nhng b iu khin MELSEC FX ph hp vi tt c cc tiu chun cng nghipquc t chnh.


30/137


Figure 1.21

FX1N kt hp nhng li ch ca mt b iu khin gn khng t vi nhng kh nng m rng linh hotca mt h iu khin m un. N c th c m rng cho ti 128 u vo v nhng u ra v vi mtphm vi ton din ca nhng m un chc nng c bit. FX1N cng lm ni bt mt b iu khin nhv tng hp mnh.

Th truyn thng ca FX1N v nhng kh nng ni d liu lm cho n tr nn l tng cho nhng ng

dng ni kch thc phn cng b iu khin, nhng c tnh truyn thng, nhng chc nng v tc xl c bit l mi th ph bnh.Nhng u im ca lot FX1N:- 14 ti 128 u vo v nhng u ra- Tc x l cao- Ample lp trnh dung lng nh (nhng bc 8,000) v nhng phm vi thit b- Hp nht b iu khin nh v- Ton din phm vi ca chc nng v nhng m un m rng c bit cho nhng yu cu ring l- Tch hp b iu khin PID- Cung cp kt ni m nhng mng- Tch hp ng h thi gian thc- Giao din lp trnh thn thin vi n v lp trnh b phn mm ng dng hay cm tay lp trnh trn

nn Windows MS

S x l tn hiu tng t vi nhng b tip hp m rng chnThe FX2N t nhng tiu chun trong khu vc k thut t ng cng nghip v l mt trong nhngb iu khin tiu th- ln nht worldwide. N c nhiu c tnh bnh thng c tm thy trong nhngb iu khin ln hn Ch dn FX2N lgc l mt trong nhng h thng PLC gn nhanh nht sn c. N cnhng kh nng truyn thng v mt phm vi rng ca s m rng rng ln v nhng m un chc nngc bit sn c cho cu hnh ca nhng h thng chnh xc.


31/137

25

Figure 1.22

Hng Siemens (c)

Figure 1.23

PAC Sn phm tch hp gia PLC v WinCC lp trnh iu khin v m phng h thngiu khin t ng


32/137


Figure 1.24

Figure 1.25

1.5 Cu trc phn cng PLC S7-3001.5.1 H thng Module5

PLC S7-300 cu trc dng module gm cc thnh phn sau:5This content is available online at .


33/137

27

CPU cc loi khc nhau: 312IFM, 312C, 313, 313C, 314, 314IFM, 314C, 315, 315-2 DP, 316-2 DP,318-2,

Module tn hiu SM xut nhp tn hiu tng ng /s: SM321, SM322, SM323, SM331, SM332,SM334,SM338, SM374

Module chc nng FM Module truyn thng CP Module ngun PS307 cp ngun 24VDC cho cc module khc, dng 2A, 5A, 10A Module ghp ni IM: IM360, IM361, IM365

Cc module c gn trn thanh ry nh hnh di, ti a 8 module SM/FM/CP bn phi CPU, tothnh mt rack, kt ni vi nhau qua bus connector gn mt sau ca module . Mi module c gn mts slot tnh t tri sang phi, module ngun l slot 1, module CPU slot 2, module k mang s 4 . . .

Figure 1.26

Nu c nhiu module th b tr thnh nhiu rack (tr CPU312IFM v CPU313 ch c mt rack), CPU rack 0, slot 2, k l module pht IM360, slot 3, c nhim v kt ni rack 0 vi cc rack 1, 2, 3, trn mirack ny c module kt ni thu IM361, bn phi mi module IM l cc module SM/FM/CP. Cp ni haimodule IM di ti a 10m. Cc module c nh s theo slot v dng lm c s t a ch u cho ccmodule ng vo ra tn hiu. i vi CPU 315-2DP, 316-2DP, 318-2 c th gn a ch ty cho cc module.


34/137


Figure 1.27

Mi a ch tng ng vi mt byte. Vi cc module s a ch mt ng vo hay ra l x.y, x l a chbyte, y c gi tr t 0 n 7. V d module SM321 DI 32 c 32 ng vo gn k CPU slot 4 c a ch l I0.y,I1.y, I2.y, I3.y, I l k hiu ch ng vo s. Module analog c a ch theo word, v d module SM332 AO4c 4 ng ra analog gn slot 5 rack 1 c a ch PQW400, PQW402, PQW404, PQW406, ng ra s c khiu l Q cn ng vo analog k hiu l PIW.

Cc CPU 312IFM, 314 IFM, 31xC c tch hp sn mt s module m rng

CPU 312IFM, 312C: 10 ng vo s a ch I124.0 . . .I124.7, I125.1; 6 ng ra s Q124.0. . .Q124.5.

CPU 313C: 24 DI I124.0..126.7, 16DO Q124.0..125.7, 5 ng vo tng ng AI a ch 752..761, haing ra AO 752..755 CPU 314IFM: 20 ng vo s I124.0 . . . I126.3; 16 ng ra s Q124.0 . . .Q125.7; 4 ng vo tng ng

PIW128, PIW130, PIW132, PIW134; mt ng ra tng ng PQW128.

1.5.1.1 Module CPU

Cc module CPU khc nhau theo hnh dng chc nng, vn tc x l lnh. Loi 312IFM, 314IFM khng cth nh. Loi 312IFM, 313 khng c pin nui. Loi 315-2DP, 316-2DP, 318-2 c cng truyn thng DP. Ccn bo c ngha sau:

- SF ... () ... li phn cng hay mm,- BATF ... () ... li ngun nui,- DC5V ... (l cy) ... ngun 5V bnh thng,- FRCE ... (vng ) ... force request tch cc- RUN ... (l cy) ... CPU mode RUN ; LED chp lc start-up w. 1 Hz; mode HALT w. 0.5 Hz- STOP mode ... (vng) ... CPU mode STOP hay HALT hay start-up; LED chp khi memory reset

request- BUSF ... () ... li phn cng hay phn mm giao din PROFIBUSKha mode c 4 v tr:- RUN-P ch lp trnh v chy- RUN ch chy chng trnh- STOP ngng chy chng trnh


35/137

29

- MRES reset b nhTh nh c th c dung lng t 16KB n 4MB, cha chng trnh t PLC chuyn qua v chuyn

chng trnh ngc tr li cho CPU.Pin nui gip nui chng trnh v d liu khi b mt ngun (ti a 1 nm), ngoi ra cn nui ng h

thi gian thc. Vi loi CPU khng c pin nui thi cng c mt phn vng nh c duy tr.Thng qua cng truyn thng MPI (MultiPoint Interface) c th ni : my tnh lp trnh, mn hnh OP

(Operator panel) , cc PLC c cng MPI (S7-300, M7-300, S7-400, M7-400, C7-6xx), S7-200, vn tc truynn 187.5kbps (12Mbps vi CPU 318-2, 10.2 kbps vi S7-200) . Cng Profibus DP ni cc thit b trn theomng Profibus vi vn tc truyn ln n 12Mbps.

Figure 1.28

* Cc vng nh ca PLCVng nh chng trnh (load memory) cha chng trnh ngi dng (khng cha a ch k hiu v

ch thch) c th l RAM hay EEPROM trong CPU hay trn trn th nh.Vng nh lm vic (working memory) l RAM, cha chng trnh do vng nh chng trnh chuyn

qua; ch cc phn chng trnh cn thit mi c chuyn qua, phn no khng cn li vng nh chngtrnh , v d block header, data block

Vng nh h thng (system memory) phc v cho chng trnh ngi dng, bao gm timer , counter,


36/137


vng nh d liu M, b nh m xut nhp. . .Trn CPU 312IFM v 314 IFM vng nh chng trnh l RAM v EEPROM; cc CPU khc c pin nui,

vng nh chng trnh l RAM v th nh. Khi mt ngun hay ch MRES ( reset b nh) RAM sb xa. Mt s vng nh ca RAM ( timer, counter, vng nh M, khi d liu..) c th khai bo l lu gi(retentive) bng phn mm S7 chuyn cc vng ny sang b nh lu gi (NVRAM non volative ) dkhng c pin nui, kch thc c th ty loi CPU.

Bng sau cho mt s thng s chnh ca cc CPU


37/137

31

Figure 1.29


38/137


1.5.1.2 Module ngun nui (PS)

Figure 1.30

Module ngun nui. C 3 loi:2A, 5A, 10A.

1.5.1.3 Module m rng cng tn hiu vo/ra (SM)

Module vo s c cc loi sau:

SM 321; DI 32 _ 24 VDC SM 321; DI 16 _ 24 VDC SM 321; DI 16 _ 120 VAC, 4*4 nhm SM 321; DI 8 _ 120/230 VAC, 2*4 nhm SM 321; DI 32 _ 120 VAC 8*4 nhm

Module ra s:

SM 322; DO 32 _ 24 VDC/0.5 A, 8*4 nhm SM 322; DO 16 _ 24 VDC/0.5 A, 8*2 nhm


39/137

33

SM 322; DO 8 _ 24 VDC/2 A, 4*2 nhm SM 322; DO 16 _ 120 VAC/1 A, 8*2 nhm SM 322; DO 8 _ 120/230 VAC/2 A, 4*2 nhm SM 322; DO 32_ 120 VAC/1.0 A, 8*4 nhm SM 322; DO 16 _ 120 VAC ReLay, 8*2 nhm SM 322; DO 8 _ 230 VAC Relay, 4*2 nhm SM 322; DO 8 _ 230 VAC/5A Relay,1*8 nhm

1.5.1.4 Module vo/ ra

SM 323; DI 16/DO 16 _ 24 VDC/0.5 A SM 323; DI 8/DO 8 _ 24 VDC/0.5 A

1.5.1.5 Module Analog in

Module analog in c nhiu ng vo, dng o in p, dng in, in tr ba dy, bn dy, nhit . Cnhiu tm o, phn gii, thi gian chuyn i khc nhau. Ci t thng s hot ng cho module bngphn mm S7- Simatic 300 Station Hardware v/hoc chng trnh ngi dng s dng hm SFC 55, 56,57 ph hp (xem mc ) v/hoc ci t nh modulle tm o (measuring range module) gn trn moduleSM. Kt qu chuyn i l s nh phn ph hai vi bit MSB l bit du.

Figure 1.31

SM331 AI 2*12 : module chuyn i hai knh vi sai p hoc dng, hoc mt knh in tr 2/3/4 dy,dng phng php tch phn, thi gian chuyn i t 5ms n 100ms, phn gii 9, 12, 14 bit + du, cctm o nh sau: 80 mV; 250 mV; 500 mV; 1000 mV; 2.5 V; 5 V;1 .. 5 V; 10 V; 3.2 mA; 10 mA; 20 mA; 0 .. 20 mA; 4 ..20 mA. in tr 150 [U+F057]; 300 [U+F057]; 600 [U+F057]; o nhiy dng cp nhit E, N, J, K, L, nhit k in tr Pt 100, Ni 100. Cc thng s mc nh c ci sn


40/137


trn module, kt hp vi t v tr ca module tm o (bn v tr A, B, C, D) nu khng cn thay i thc th s dng ngay

Figure 1.32

Figure 1.33


41/137

35

Figure 1.34

Figure 1.35

SM331, AI 8*12bit , 8 knh vi sai chia lm hai nhm, phn gii 9 (12, 14 ) bit + du SM331, AI 8*16bit , 8 knh vi sai chia lm 2 nhm , phn gii 15 bit + du

Module Analog Out:


42/137


Cung cp p hay dng ph thuc s nh phn ph hai- SM332 AO 4*12 bit: 4 ng ra dng hay p phn gii 12 bit, thi gian chuyn i 0.8 ms .- SM332 AO 2*12 bit- SM332 AO 4*16 bitModule Analog In/Out- SM 334; AI 4/AO 2 * 8 Bit- SM334; AI 4/AO 2* 12 Bit

Figure 1.36


43/137

37

1.5.1.6 Module ghp ni (IM)

Module IM360 gn rack 0 k CPU dng ghp ni vi module IM361 t cc rack 1, 2, 3 gip kt nicc module m rng vi CPU khi s module ln hn 8. Cp ni gia hai rack l loi 368. Trong trng hp

ch c hai rack, ta dng loi IM365.

Figure 1.37

1.5.1.7 Module c chc nng iu khin ring (FM)

FM350-1 : m xung mt knh FM350-2 : m xung tm knh FM351, 353, 354, 357-2 : iu khin

nh v

FM352: b iu khin cam in t FM355: b iu khin h kn

1.5.1.8 Module phc v truyn thng (CM)

Module phc v truyn thng trong mng gia cc PLC vi nhau hoc gia PLC vi my tnh


44/137


1.5.2 Cu trc b nh6

1.5.2.1 Kiu d liu

Figure 1.38



45/137

39

Figure 1.39

1.5.2.2 Vng nh d liu, i tng v cch truy cp

PLC thng yu cu b nh trong cc trng hp: Lm b nh thi cho cc knh trng thi I/O. Lm bm trng thi cc chc nng trong PLC nh nh thi, m, ghi cc Relay.

Mi lnh ca chng trnh c mt v tr ring trong b nh, tt c mi v tr trong b nh u c nhs, nhng s ny chnh l a ch trong b nh. a ch ca tng nh s c tr n bi mt b m ach bn trong b vi x l. B vi x l s gi tr trong b m ny ln mt trc khi x l lnh tip theo.Vi mt a ch mi, ni dung ca nh tng ng s xut hin u ra, qu trnh ny c gi l qutrnh c.

B nh bn trong PLC c to bi cc vi mch bn dn, mi vi mch ny c kh nng cha 2000 -16000 dng lnh , ty theo loi vi mch. Trong PLC cc b nh nh RAM, EPROM u c s dng.

+ RAM (Random Access Memory) c th np chng trnh, thay i hay xa b ni dung bt k lcno. Ni dung ca RAM s b mt nu ngun in nui b mt. trnh tnh trng ny cc PLC u ctrang b mt pin kh, c kh nng cung cp nng lng d tr cho RAM t vi thng n vi nm. Trongthc t RAM c dng khi to v kim tra chng trnh. Khuynh hng hin nay dng CMOS RAMnh kh nng tiu th thp v tui th ln.

+ EPROM (Electrically Programmable Read Only Memory) l b nh m ngi s dng bnh thngch c th c ch khng ghi ni dung vo c. Ni dung ca EPROM khng b mt khi mt ngun, nc gn sn trong my, c nh sn xut np v cha h iu hnh sn. Nu ngi s dng khngmun m rng b nh th ch dng thm EPROM gn bn trong PLC. Trn PG (Programer) c sn ch ghiv xa EPROM.

+ EEPROM (Electrically Erasable Programmable Read Only Memory) lin kt vi nhng truy xut linhng ca RAM v c tnh n nh. Ni dung ca n c th c xa v lp trnh bng in, tuy nhin s lnl c gii hn. Mi trng ghi d liu th t l a cng hoc a mm, c s dng trong my lp trnh.a cng hoc a mm c dung lng ln nn thng c dng lu nhng chng trnh ln trong mtthi gian di.


46/137


* Kch thc b nh:- Cc PLC loi nh c th cha t 300 -1000 dng lnh ty vo cng ngh ch to.- Cc PLC loi ln c kch thc t 1K - 16K, c kh nng cha t 2000 -16000 dng lnh. Ngoi ra cn

cho php gn thm b nh m rng nh RAM, EPROM.

1.5.2.2.1 Cu trc b nh:

B nh gm 48KB RAM, 48KB ROM, khng c kh nng m rng v tc x l gn 0.3ms trn 1000 lnhnh phn, b nh c chia trn cc vng:

+ Vng cha chng trnh ng dng:- OBx (Organisation block): Min cha chng trnh t chc, trong :- Khi OB1: Khi t chc chnh, mc nh, thc thi lp vng. N c bt u khi qu trnh khi ng

hon thnh v bt u tr li khi n kt thc.- Khi OB10 (Time of day interrupt): c thc hin khi c tn hiu ngt thi gian.- Khi OB20 (Time delay interrupt): c thc hin sau 1 khong thi gian t trc.- Khi OB35 (Cyclic Interrupt): khi ngt theo chu k nh trc- Khi OB40 (Hardware Interrupt): c thc hin khi tn hiu ngt cng xut hin ng vo I124.0

I124.3- FC (Function): Min cha chng trnh con c t chc thnh hm c bin hnh thc trao i d

liu vi chng trnh gi n, c phn bit bi cc s nguyn. V d: FC1, FC7, FC30ngoi ra cn ccc hm SFC l cc hm c tch hp sn trong h iu hnh.

- FB (Function Block): tng t nh FC, FB cn phi xy dng 1khi d liu ring gi l DB (DataBlock) v cng c cc hm SFB l cc hm tch hp sn trong h iu hnh.

+ Vng cha cc tham s h iu hnh v chng trnh ng dng:- I (Process image input): Min b m d liu cc ng vo s. Trc khi bt u thc hin chng trnh,

PLC s c tt c gi tr logic ca cc cng vo ri ct gi chng trong vng I. khi thc hin chng trnhCPU s s dng cc gi tr trong vng I m khng c trc tip t ng vo s.

- Q (Process image output): tng t vng I, min Q l b m d liu cng ra s. Khi kt thc chngtrnh, PLC s chuyn gi tr logic ca b m Q ti cc cng ra s.

- M (Memory): Min cc bin c. Do vng nh ny khng mt sau mi chu k qut nn chng trngng dng s s dng vng nh ny lu gi cc tham s cn thit. C th truy nhp n theo bit (M), byte(MB), theo t (MW) hay t kp (MD).

- T (Timer): Min nh phc v b thi gian bao gm vic lu tr cc gi tr t trc (PV-Preset Value),cc gi tr tc thi (CV-Current Value) cng nh cc gi tr logic u ra ca Timer.

- C (Counter): Min nh phc v b m bao gm vic lu gi cc gi tr t trc (PV-Preset Value),cc gi tr tc thi (CV-Current Value) cng nh cc gi tr logic u ra ca Counter.

- PI: Min a ch cng vo ca cc module tng t (I/O External input). Cc gi tr tng t ti cngvo ca module tng t s c module c v chuyn t ng theo nhng a ch. Chng trnh ng dngc th truy cp min nh PI theo tng byte (PIB), tng t (PIW) hoc theo tng t kp (PID).

- PQ: Min a ch cng ra ca cc module tng t (I/O External output). Cc gi tr tng t ti cngvo ca module tng t s c module c v chuyn t ng theo nhng a ch. Chng trnh ng dngc th truy cp min nh PI theo tng byte (PQB), tng t (PQW) hoc theo tng t kp (PQD).

+ Vng cha cc khi d liu, c chia thnh 2 loi: DB (Data block): Min cha cc d liu c t chc thnh khi. Kch thc hay s lng khi do

ngi s dng qui nh. C th truy nhp min ny theo tng bit (DBX), byte( DBB), tng t (DBW),t kp (DBD).

L (Local data block): Min d liu a phng, c cc khi chng trnh OB, FC, FB t chc v sdngcho cc bin nhp tc thi v trao i d liu ca bin hnh thc vi nhng khi gi n. Tonb vng nh s b xo sau khi khi thc hin xong. C th truy nhp theo tng bit (L), byte (LB), tLW), hoc t kp (LD).


47/137

41

Kch thc cc vng nh ty thuc vo tng loi PLC

Figure 1.40

1.5.2.2.2 Phng php truy cp vng nh:

a ch nh trong PLC S7-300 bao gm hai thnh phn: phn ch v phn s.


48/137


V d:

Figure 1.41

Truy nhp theo byte: Bao gm cc kiu Byte (1 byte), Word (2 byte), Double word (4 byte)Quy cch: Tn vng nh, kch thc, a ch byte u tin

1.5.2.2.2.1 Vng nh cc u vo I:

- Ti thi im u tin mi vng qut PLC ly tn hiu t cc u vo v ghi cc gi tr tng ng vovng nh u vo.

- Truy nhp: Kiu: Bit I[a ch byte].[a ch bit] I0.1Byte, word, Double word I[kch thc][a ch byte u tin]V d: IB4, IW1, ID2

1.5.2.2.2.2 Vng nh cc u ra Q:- Trong qu trnh thc hin cc cng vic trong mt vng qut (bao gm c chng trnh iu khin), PLCs ghi cc gi tr tng ng ca cc vo vng nh ny, cui vng qut PLC s gi cc gi tr ny n ccu ra tng ng.

- Truy nhp: Kiu: Bit Q[a ch byte].[a ch bit] Q0.0Byte, word, Double word Q[kch thc][a ch byte u tin]V d: QB2, QW1, QD4

1.5.2.2.2.3 Vng nh M:

- Cc nh thuc vng nh (M) dng lu tr trng thi ca qu trnh hot ng hoc cc thng tin iukhin khc.

- Truy nhp:Kiu: Bit M[a ch byte].[a ch bit] M10.1Byte, Word, Double word M[kch thc][a ch byte u tin]V d: MB20, MW8, MD6

1.5.2.2.2.4 Vng nh thi gian T

- Mi b thi gian c hai gi tr c lu tr trong vng nh T: Gi tr m thi gian hin ti (16 bit), vgi tr bit timer (1 bit).

- Truy nhp: T [s th t b timer] T3


49/137

43

1.5.2.2.2.5 Vng nh b m C:

- Mi b m c hai gi tr c lu tr trong vng nh C: Gi tr m hin ti (kiu BDC, 12 bit), v gitr bit counter (1 bit).

- Truy nhp: C [s th t b timer] C1

1.5.2.2.2.6 Vng nh cc u vo, u ra Analog AI, AQ:

- PLC chuyn i mt gi tr in p (hoc dng in) thnh mt s nh phn (12 bit) lu tr trong vngnh analog (hoc ngc li).

- Cch truy nhp vi tn hiu vo: PI[kch thc][a ch byte u tin]V d: Truy nhp: Kiu: Byte, Word, Double wordPIB20, PIW8, PID6- Cch truy nhp vi tn hiu ra: PQ[kch thc][a ch byte u tin]V d: Truy nhp: Kiu: Byte, Word, Double wordPQB20, PQW8, PQD6

1.5.2.2.2.7 Vng nh ca cc khi d liu DB:- M khi d liu DB hoc DI bng lnh OPN

V d: OPN DB 1 // M khi d liu DB (Open data Block)Hoc OPN DI 1 // M khi d liu DI (Open instance data Block)- M mt bt trong khi d liu DBXV d: A DB3.DB 0.5 // m bit s 5 ca byte 0 trong khi d liu DB3- M mt Byte, mt WORD hoc mt mt DW trong khi d liu DBxV d: L DB3. DBB2 // ch ti Byte 2 trong khi d liu DB3L DB3. DBW2 // ch ti WORD 2 trong khi d liu DB3L DB. DBD2 // ch ti DWORD 2 trong khi d liu DB3

1.5.2.2.2.8 Vng nh trong cc khi chng trnh OB, FBx v FCx

- Ch 1 bitV d: A L0.2// ch bt s 2 ca Byte 0 trong min d liu a phng- Ch mt Byte, Word hoc DWV d: L LB0 // ch byte 0 trong min d liu a phngL LW0 // ch Word 0 trong min d liu a phngL LD0 // ch DWord 0 trong min d liu a phng


50/137



51/137

Chng 2

Chng 2 : Ngn ng lp trnh v ngdng

2.1 Gii thiu cc ngn ng lp trnh1

Lp trnh cho S7 v cc PLC khc ca hng Siemens da trn 3 phng php c bn:- Phng php hnh thang (Ladder logic - LAD).- Phng php khi hm (Function Block Diagram - FBD).- Phng php lit k cu lnh (Statement List - STL).Chng ny s gii thiu cc thnh phn c bn ca ba phng php v cch s dng chng trong lp

trnh.Nu chng trnh c vit theo ngn ng LAD (hoc FBD) th c th chyn sang ngn ng STL hay

FBD (hoc LAD) tng ng. Nhng khng phi bt c chng trnh vit theo STL no cng chuyn sangngn ng LAD hay FBD c. B tp lnh STL c trnh by trong gio n ny u c mt chc nngnh cc tip im, cun dy, cc hp (trong LAD) hay IC s trong FBD.

Nhng lnh ny phi phi hp c trng thi cc tip im quyt nh v gi tr trng thi u rahoc gi tr logic cho php hoc khng cho php thc chc nng ca mt (hay nhiu) cun dy hoc hp.Trong lp trnh lgic thng hay s dng hai ngn ng LAD v STL v n gn gi hn i vi chuyn ngnhin. Sau y l nhng nh ngha cn phi nm khi bt tay vo thit k mt chng trnh:

2.1.1 Ngn ng bng lnh (STL)Ngn ng lit k lnh, k hiu l STL (Statement List). y l ngn ng lp trnh thng thng ca mytnh. Mt chng trnh c ghp bi nhiu lnh theo mt thut ton nht nh, mi lnh chim mt hngv u c cu trc chung l: "tn lnh" + "ton hng". Mt s lnh c bit th c th ch c tn lnh mkhng cn ton hng.

V d:1

This content is available online at .

45


52/137

46 CHNG 2. CHNG 2 : NGN NG LP TRNH V NG DNG

Figure 2.1

2.1.2 Ngn ng s thang (LAD)Ngn ng hnh thang, k hiu l LAD (Ladder Logic) Vi loi ngn ng ny rt thch hp vi ngi quenthit k mch iu khin logic. Chng trnh c vit di dng lin kt gia cc cng tc:

V d:


53/137

47

Figure 2.2

2.2 Chu trnh lm vic, lp trnh v cu trc chng trnh2

2.2.1 Cc phng php lp trnh

2.2.1.1 Lp trnh tuyn tnh

Phn b nh ca CPU dnh cho chng trnh ng dng c tn gi l logic Block. Nh vy logic block l tnchung gi tt c cc khi bao gm nhng khi chng trnh t chc OB, khi chng trnh FC, khi hmFB.

Trong cc loi khi chng trnh th ch c khi duy nht khi OB1 c thc hin trc tip theovng qut. N c h iu hnh gi theo chu k lp vi khng thi gian khng cch u nhau m ph thucvo di ca chng trnh. Cc loi khi chng trnh khc khng tham gia vo vng qut.

Vi t chc chng trnh nh vy th phn chng trnh trong khi OB1 c y iu kin ca mtchng trnh iu khin thi gian thc v ton b chng trnh ng dng c th ch cn vit trong OB1 l nh hnh v sau.

Cch t chc chng trnh vi ch mt khi OB1 duy nht nh vy c gi l lp trnh tuyn tnh.2This content is available online at .


54/137


Figure 2.3

Khi OB1 c h thng gi xoay vng lin tc theo vng qut.Cc khi OB khc khng tham gia vo vng qut c gi bng nhng tn hiu bo ngt. S7-300 c nhiu

tn hiu bo ngt nh tn hiu bo ngt khi c s c ngun nui, c s c chp mch cc modul m rng,tn hiu bo ngt theo chu k thi gian, v mi loi tn hiu bo ngt nh vy cng ch c kh nng gi mtkhi OB nht nh. V d tn hiu bo ngt s c ngun nui ch gi khi OB81, tn hiu bo ngt truynthng ch gi khi OB87.

Mi khi xut hin tn hiu bo ngt h thng s dng cng vic ang thc hin li, chng hn nh tm

dng vic thc hin chng trnh trong OB1, v chuyn sang thc hin chng trnh x l ngt tong cckhi OB tng ng. V d khi ang thc hin chng trnh trong khi OB1 m xut hin ngt bo s ctruyn thng, h thng s tm dng vic thc hin chng trnh trong OB1 li gi chng trnh trongkhi truyn thng OB87. Ch sau khi thc hin xong chng trnh trong khi OB87 th h thng miquay tr v thc hin tip tc phn chng trnh cn li trong OB1.

2.2.1.2 Lp trnh cu trc

Vi kiu lp trnh c cu trc th khc v ton b chng trnh iu khin c chia nh thnh cc khi FCv FB mang mt nhim v c th ring v c qun l chung bi nhng khi OB. Kiu lp trnh ny rtph hp cho nhng bi ton phc tp, nhiu nhim v v li rt thun li cho vic sa cha sau ny.


55/137

49

Figure 2.4

Khi OB (Organization Block): Khi t chc v qun l chng trnh iu khin. C nhiu loi khiOB vi nhng chc nng khc nhau ,chng c phn bit vi nhau bng mt s nguyn i sau nhm

k t OB.V d: OB10, OB85, ...

Khi FC (Program Block): Khi chng trnh vi nhng chc nng ring ging nh 1 chng trnhcon hoc mt hm ( chng trnh con c bin hnh thc). Mt chng trnh ng dng c th c nhiukhi FC v cc khi FC ny c phn bit vi nhau bng mt s nguyn sau nhm k t FC.

V d: FC1,FC2. . ..

Khi FB (Function Block): L loi khi FC c bit c kh nng trao i 1 lng d liu ln vi cckhi chng trnh khc .Cc d liu ny phhi c t chc thnh khi d liu ring c tn gi lData block.Mt chng trnh ng dng c th c nhiu khi FB v cc khi Fb ny c phn bitvi nhau bng mt s nguyn sau nhm k t FB. Chng hn nh FB1,FB2 . . .

Khi DB (Data Block): Khi cha cc d liu cn thit thc hin chng trnh. Cc tham s ca

khi do ngi dng t t .Mt chng trnh ng dng c th c nhiu khi DB v cc khi DB nyc phn bit vi nhau bng mt s nguyn sau nhm k t DB. V d: DB1,DB2,...

Chng trnh trong cc khi c lin kt vi nhau bng cc lnh gi khi, chuyn khi. Xem nhng phnchng trnh trong cc khi nh l cc chng trnh con th S7_300 cho php gi chng trnh con lngnhau ,tc l chng trnh con ny gi mt chng trnh con khc v t mt chng trnh con c gi ligi ti mt chng trnh con th 3,. . . S cc lnh gi lng nhau ph thuc vo tng chng loi module CPUm ta ang s dng. V d i vi module CPU 314 th s lnh gi lng nhau nhiu nht c th cho php l8.Nu s ln gi khi lng nhau m vt qu con s gii hn cho php ,PLC s t chuyn qua ch Stopv t c bo li.


56/137


2.2.1.3 Cc khi OB c bit

Trong khi khi OB c thc hin u n tng vng qut trong giai on thc hin chng trnh th cckhi OB khc ch c thc hin khi xut hin tn hiu bo ngt

tng ng ,ni cch khc chng trnh vit cho cc khi OB ny chnh l chng trnh x l tn hiu ngt(event).Chng bao gm:

OB10 ( Time of Day Interrupt):Chng trnh trong khi s c thc hin khi gi tr ca ng h thigian thc nm trong mt khong thi gian c quy nh. OB10 c th gi mt ln ,nhiu ln cchu nhau tng pht, tng gi,tng ngy . . ..Vic quy nh khong thi gian hay s ln gi OB10 cthc hin nh chng trnh h thng SFC28 hoc trong bng tham s ca module CPU nh phn mmStep 7.

OB20 ( Time Day Interrupt): Chng trnh trong khi s c thc hin sau mt khong thi gian trt trc k t khi gi chng trnh h thng SFC32 t thi gian tr.

OB35 (Cyclic Interrupt): Chng trnh trong OB35 s c thc hin cch u nhau 1 khong thigian c nh.Mc nh khong thi gian ny s l 100ms,xong ta c th thay i n trong bng thams ca module CPU ,nh phn mm Step7.

OB40 (Hardware Interrupt) : Chng trnh trong OB s c thc hin khi xut hin 1 tn hiu bongt t ngoi vi a vo module CPU thng qua cc cng vo ra s onboard c bit,hoc thng quacc module SM,CP,FM OB80 (Cycle Time Fault): Chng trnh trong khi OB80 s c thc hinkhi thi gian vng qut(Scan time) vt qu khong thi gian cc i c quy nh hoc khi cmt tn hiu ngt gi mt khi OB no m khi OB ny cha kt thc ln gi trc.Mc nhthi gian Scan time cc i l 150ms ,nhng c th thay i n thng qua bng tham s ca moduleCPU nh phn mm Step 7.

OB81 (Power Supply fault): CPU s gi chng trnh trong khi OB81 khi pht hin thy c li vngun nui.

OB82( Diagnostic Interrupt):Chng trnh trong OB82 c gi khi CPU pht hin s c t cc Modulvo ra

OB85( Not Load fault):Chng trnh trong OB82 c gi khi CPU pht hin thy chng trnh ngdng c s dng ch ngt nhng chng trnh s l tn hiu ngt li khng c trong khi OB tng

ng. OB87 ( Communication fault):Khi OB87 s c gi khi CPU pht hin thy li trong truyn thng

v d nh khng c tn hiu tr li t cc i tc. OB100 ( Start Up Information):Khi OB100 s c thc hin 1 ln khi CPU chuyn trng thi Stop

sang Run. OB121 ( Synchronous error):Khi OB121 s c gi khi CPU pht hin thy li logic trong chng

trnh nh i sai kiu d liu hoc li truy nhp khi DB ,FC,FB khng c trong b nh CPU. OB122 ( Synchronous error):Khi OB122 s c gi khi CPU pht hin thy li truy cp module

trong chng trnh,v d chng trnh c lnh truy nhp module vo ra m rng nhng li khng tmthy module ny.

SFB: System Function blockSFC: System function

SDB: System Data BlockCh : FB lun s dng chung vi DB

2.2.2 Chu trnh lm vicPLC thc hin chng trnh theo mt chu trnh kn c lp li lin tc cho n khi no c lnh dng. Mivng lp hay cn gi l vng qut c bt u bng vic qut cc s liu t cc knh vo/ra, chuyn ccs liu ny n vng nh m u vo/ra, tip theo l bc thc hin cc lnh tip theo ca chng trnhnh thc hin cc php tnh logic, cc php tnh s hc xc nh cc tc ng iu khin, bc k tip


57/137

51

l chuyn d liu t b nh m u ra n cc knh ra. Khi c mt lnh dng no xut hin th PLCs dng cc hot ng x l thng tin v truyn tin kim tra khi chng trnh tng ng vi lnh ngt.

Figure 2.5

Vng qut cng t lnh dng th thc hin cng nhanh. Nu chng trnh hot ng bnh thng th chuk ca mi vng qut c di nh nhau. Tc qut cng cao th c th cho php nhp c nhiu sliu gn nh ng thi trong thi gian qut, v nh vy kh nng iu khin c ng thi nhiu i lngl hon ton c th thc hin c. Kh nng x l tn hiu trong mt chu trnh iu khin khng c hintng tr cn c gi l iu khin trong thi gian thc. Cc PLC v cc PC ngy nay c tc x l rtcao nn cht lng ca cc h thng iu khin s khng km cht lng ca cc h thng iu khin tngt. Chu k qut ca PLC thng vo khong t 1 n 25 mi li giy. Thi gian qut u vo v u ra tng

i ngn so vi chu k qut ca PLC. Phn ln thi gian dng cho vic tnh ton cc hm iu khin.Thng thng chng trnh c np vo PLC bi b lp trnh cm tay, thit b lp trnh chuyn dnghay my tnh c nhn. B lp trnh cm tay thng dng cho cc PLC r tin, n gin. B lp trnh chuyndng c trang b mn hnh v cc phm tng ng vi cc phn t ca s thang tin cho vic lptrnh. Cc thit b ny cho php kim tra vic thc hin cc lnh ca chng trnh trong thi gian thc.Ngy nay ta thng s dng cc phn mm lp trnh cho PLC trn my tnh v sau khi chay th m phngc th np vo PLC thng qua cng RS232.

B np EPROM cho php np chng trnh ghi trn EPROM vo b nh ca PLC. Thit b m phngthng gn vi cc i t quang in LED hoc cc cang tc th nghim cc bc ca chng trnh logic.


58/137


B x l ho thng dng lm giao din gia h thng m phng v h thng hin th bng mnhnh.

Cc PLC hot ng lin tc t lc c bt ln. Khc vi my tnh thng thng, PLC khng cn c hiu hnh, khng cn c phn mm no ngoi phn mm ca ngi s dng v ring i vi cc my CNChoc r bt c th c thm phn mm ho dng cho m phng cc qu trnh gia cng hay cc hot ngca r bt . PLC ln lt c cc u vo, thc hin tnh ton, xc nh cc tc ng iu khin, trun cctc ng iu khin n u ra v lp li. Kt ni vi m un vo l cc i lng vt l. Cc i lng vony c th l c hai dng:

- Cc i lng tng t (analog): l cc i lng n t cc cm bin tng t.- Cc i lng l gc: l cc i lng th hin cc trng thi hay cc iu kin thc hin mt hm

l gc hay chnh l cc quyt nh l gc. Cc i lng ny n t cc cng tc, cm bin s.Cc m un ra kt ni cc u ra vi cc ng c, cc cun ht, cc n tn hiu vv. Tc ng ca

chng trnh iu khin l cc thao tc khi ng ng c, dng ng c, bt/tt n, kch hot mt c cuno vv.

Tt c cc PLC u thc hin cc chc nng iu khin v mt bn cht l ging nhau. Tuy nhin vcch th bng lp trnh c th khc nhau, ph thuc vo nh sn xut PLC.

Mi u vo ca PLC c ni vi mt hay nhiu thit b m qua dng in b chn li hay c choi qua. Nu c in p trn u vo th u vo c c xem nh ang trng thi bt. Ngc linu khng c in p trn u vo, c ngha l u vo ang trng thi tt.

PLC kim tra trng thi cc u vo v so snh vi chng trnh l gc ng hay ngt tn hiu inp trn u ra. Cc PLC khng cn bit n cc cc thit b c c kt ni vo n qua m un vo haym un ra hay khng, m chng ch n gin l kim tra cc trng thi ca cc u vo v bt hay tt ccu ra tng ng vi l gc ca chng trnh iu khin.

Mi vng iu khin hon thnh c gi l mt chu k qut. Thi gian ca mt chu k l rt quantrng, v n lin quan n s lng cc y ra c th iu khin c ca PLC. Thi gian chu k cng nhPLC cng hoath ng nhanh, cng c th iu khin c nhiu i lng vt l khc nhau. Chnh v vyPLC tr nn thit b iu khin l tng cho cc my v thit b cng nghip.

Khi cha c chng trnh iu khin PLC khng th hot ng c. PLC ch hot ng khi cchng trnh iu khin np vo b nh ca n. Chng trnh iu khin c th np vo PLC bng 3 phng

php khc nhau:- Lp trnh nh cc phn mm lp trnh trn my tnh v np chng trnh ln PLC qua cng RS232hay qua cng kt ni vi mng LAN hay mng Internet. My tnh c nhn l phng tin lp trnh tt nhtcho PLC, bi v chng ta c th quan st c nhiu dng lnh trn mn hnh, son tho v truy cp vochng trnh d dng. iu bt tin l my tnh c nhn khng thch hp lm vi mi trng cng nghipv kh nng di chuyn km.

- Lp trnh bng thit b lp trnh sch tay: lp trnh trc tip vo b nh ca PLC. Thit b ny khngd s dng nh my tnh, nhng li tin cho vic mang i theo ngi. Lp trnh c thc hin tng dnglnh tng ng vi tng bc ca s thang.

- Lp trnh trn my tnh, np ln th nh v sau np t th nh vo PLC qua cng tiu chun. Ccth nh EEPROM l cc b nh ROM c th xo v lp trnh li c bng in. u im ca EEPROMl n c th thay i chng trnh ca PLC bng cch cm vo cng ca PLC.

Khi np chng trnh iu khin t PC n PLC, chng trnh c th chy c, n phi c np

vo b nh ca b x l. Khi np chng trnh trc tip t PC cn phI ch cc thao tc sau:1. Tt c cc phn t c lin quan n PLC phi c ngt in.2. Ni PC vi PLC3. Chuyn cng tc trn b x l sang ch iu khin t xa.4. Bt cng tc ngun cp in vo PLC v cc b phn ca n.5. Thc hin bc ti chng trnh iu khin t PC v PLC.6. Khi vic ti chng trnh hon tt, chuyn sang ch gin tip, ngng kt ni vi PC (stay offline).

Lc ny PLC c th chy chng trnh mi np v.


59/137

53

2.3 Tp lnh PLC S7 - 3002.3.1 Nhm lnh logic tip im3

2.3.1.1 Hm AND: Ton hng l kiu d liu BOOL hay a ch bit I, Q, M, T, C, D, L

Figure 2.6

Tn hiu ra Q4.0 s bng 1 khi ng thi tn hiu I0.0=1 v I0.1=1.D liu vo v ra :Vo: I0.0, I0.1: BOOLRa : Q4.0 : BOOLV d: Mt ng c ko bng ti hot ng khi n v gi ng thi hai nt n S1 v S2:



60/137


2.3.1.2 Hm OR: Ton hng l kiu d liu BOOL hay a ch bit I, Q, M, T, C, D, L.

Figure 2.7

Tn hiu ra s bng 1 khi c t nht mt tn hiu u vo bng 1.D liu vo v ra :Vo: I0.0, I0.1: BOOLRa : Q4.0 : BOOLV d: Mt bng n s sng nu nhn 1 trong hai cng tc S 1 hoc S2

2.3.1.3 Hm NOT: Tn hiu u ra l nghch o ca tn hiu u vo

Figure 2.8

D liu vo raVo: I0.0: BOOL Ra: Q4.0: BOOL


61/137

55

2.3.1.4 Hm XOR: Ton hng l kiu d liu BOOL hay a ch bit I, Q, M, T, C, D, L.

Figure 2.9

Tn hiu u ra s bng 1 khi 2 tn hiu u vo nghch o nhau.

2.3.1.5 Lnh xo RESET: Ton hng l a ch bit I, Q, M, T, C, D, L.

Figure 2.10

Tn hiu ra Q4.0 s b xo khi tn hiu u vo I0.0 = 1.


62/137


2.3.1.6 Lnh SET: Ton hng l a ch bit I, Q, M, T, C, D, L.

Figure 2.11

Tn hiu ra Q4.0 = 1 (Q4.0 s c thit lp ) khi I0.0 =1.

2.3.1.7 B nh RS: Ton hng l a ch bit I, Q, M, D, L

Figure 2.12


63/137

57

Khi I0.0 = 1 v I0.1 = 0 Merker M0.0 b Reset v u ra Q4.0 l "0". Nu I0.0 = 0 v I0.1 = 1 th Setcho M0.0 v u ra Q4.0 l "1".

Khi c hai u vo Set v Reset cng ng thi =1 th M0.0 v Q4.0 c gi tr l "1".

2.3.1.8 B nh SR: Ton hng l a ch bit I, Q, M, D, L

Figure 2.13

Khi I0.0 = 1 v I0.1 = 0 th Set cho Merker M0.0 v u ra Q4.0 l "1". Nu I0.0 = 0 v I0.0 = 1 thM0.0 b Reset v u ra Q4.0 l "0". Khi c hai u vo Set v Reset cng ng thi =1 th M0.0 v Q4.0 c gi tr l "0".

Ch : Trong k thut s trng thi ca trig RS s b cm khi R=1 v S=1. Nn y c hai loi b nhRS v SR l loi Trig u tin S hay u tin R

2.3.2 B m (Counter)4

2.3.2.1 Nguyn l hot ng

Counter thc hin chc nng m ti cc sn ln ca cc xung u vo. S7-300 c ti a l 256 b mph thuc vo tng loi CPU, k hiu bi Cx. Trong x l s nguyn trong khong t 0 n 255. TrongS7-300 c 3 loi b m thng s dng nht l : B m tin li (CUD), b m tin (CU) v b mli (CD).

Mt b m tng qut c th c m t nh sau:4This content is available online at .


64/137


Figure 2.14

Trong :CU : BOOL l tn hiu kch m tinCD : BOOL l tn hiu kch m liS : BOOL l tn hiu tPV : WORD l gi tr t trc

R : BOOL l tn hiu xoCV : WORD L gi tr m h m 16CV_BCD: WORD l gi tr m h m BCDQ : BOOL L tn hiu ra .Qu trnh lm vic ca b m c m t nh sau:S sn xung m c, c ghi vo thanh ghi 2 Byte ca b m, gi l thanh ghi C-Word. Ni dung

ca thanh ghi C-Word c gi l gi tr m tc thi ca b m v k hiu bng CV v CV_BCD. Bm bo trng thi ca C-Word ra ngoi C-bit qua chn Q ca n. Nu CV 0, C-bit c gi tr "1".Ngc li khi CV = 0, C- bit nhn gi tr 0. CV lun l gi tr khng m. B m s khng m li khi CV= 0.

i vi Counter, gi tr t trc PV ch c chuyn vo C-Word ti thi im xut hin sn ln catn hiu t ti chn S.

B m s c xo tc thi bng tn hiu xo R (Reset). Khi b m c xa c C-Word v C- bit

u nhn gi tr 0.

2.3.2.2 Khai bo s dng

Vic khai bo s dng mt Counter bao gm cc bc sau:- Khai bo tn hiu Enable nu mun s dng tn hiu ch ng kch m (S): dng d liu BOOL- Khai bo tn hiu u vo m tin CU : dng d liu BOOL- Khai bo tn hiu u vo m li CD : dng d liu BOOL- Khai bo gi tr t trc PV: dng d liu WORD- Khai bo tn hiu xo: dng d liu BOOL


65/137

59

- Khai bo tn hiu ra CV (h 16): dng d liu WORD.- Khai bo tn hiu ra CV-BCD nu mun ly gi tr m tc thi h BCD dng d liu WORD.- Khai bo u ra Q nu mun ly tn hiu tc ng ca b m. dng d liu BOOL. Trong cn ch

cc tn hiu sau bt buc phi khai bo: Tn ca b m cn s dng, tn hiu kch m CU hoc CD.

2.3.2.2.1 B m tin/li: Khai bo

Figure 2.15

Nguyn l hot ngKhi tn hiu I0.2 chuyn t 0 ln 1b m c t gi tr l 55. Gi tr u ra Q4.0 =1 .B m s thc hin m tin ti cc sn ln ca tn hiu ti chn CU khi tn hiu I0.0 chuyn gi tr

t "0" ln "1"B m s m li ti cc sn ln ca tn hiu ti chn I0.1 khi tn hiu chuyn t "0" ln "1" . Gi tr

ca b m s tr v 0 khi c tn hiu tai sn ln ca chn R ( I0.3)

2.3.2.2.2 B m tin CU: Khai bo

Nguyn l hot ngKhi tn hiu I0.2 chuyn t "0" ln "1" b m c t gi tr l 55. Gi tr u ra Q4.0 =1.B m s thc hin m tin ti cc sn ln ca tn hiu ti chn CU khi tn hiu I0.0 chuyn gi tr

t "0" ln "1" .Gi tr ca b m s tr v 0 khi c tn hiu tai sn ln ca chn R (I0.3). B m s ch

m n gi tr


66/137


Figure 2.16

2.3.2.2.3 B m li CD: Khai bo

Figure 2.17

Nguyn l hot ng

Khi tn hiu I0.2 chuyn t "0" ln "1" b m c t gi tr l 55. Gi tr u ra Q4.0 =1.


67/137

61

B m s thc hin m li ti cc sn ln ca tn hiu ti chn CD khi tn hiu I0.0 chuyn gi trt "0" ln"1".

Gi tr ca b m s tr v 0 khi c tn hiu tai sn ln ca chn R(I0.3). B m s ch m ngi tr >= 0.

V d: Vit chng trnh iu khin qun l bi xe t t ng. Cm bin S 1 pht hin xe vo, cmbin S2 pht hin xe ra. S xe trong Gara c lu vo a ch QW20.

2.3.3 B thi gian (Timer)5

2.3.3.1 Nguyn l hot ng ca b Timer

B thi gian Timer l b to thi gian tr T mong mun gia tn hiu logic u vo X(t) v u ra Y(t).

Figure 2.18

S7-300 c 5 kiu thi gian Timer khc nhau. Tt c 5 loi Timer ny cng bt u to thi gian tr tnhiu k t thi im c sn ln ca tn hiu kch u vo, tc l khi c tn hiu u vo U(t) chuyn trngthi t logic "0" ln logic"1", c gi l thi im Timer c kch.

Thi gian tr T mong mun c khai bo vi Timer bng gi tr 16 bits bao gm hai thnh phn:- phn gii vi n v l mS. Timer ca S7 c 4 loi phn gii khc nhau l 10ms, 100ms, 1s v 10s.- Mt s nguyn BCD trong khong t 0 n 999 c gi l PV (Preset Value - gi tr t trc).Nh vy thi gian tr T mong mun s c tnh nh sau:T = phn gii x PV.Ty theo ngn ng lp trnh m c th khai bo thi gian tr theo hai cch sau:



68/137


- Cch 1: S5t#5s: Cch khai bo ny dng c cho cc loi ngn ng lp trnh Step 7- Cch 2: L W#16#1350, cch khai bo ny ch dng c cho ngn ng STL xc nh c phn gii trong cch khai bo th nht ta c th tnh nh sau:p dng cng thc tnh: T = phn gii x PV; trong PV l s nguyn ln nht c th nm

trong khong 0-999. Nh vy, nu khai bo s5t#5s th c th tnh nh sau: 5s=10mS x 500, vy phngii l 10mS. Vi cch khai bo ny ta khng th thay i c phn gii v phn mm Step7 t gn chon phn gii.

Vi cch khai bo th 2 ta co th la chn phn gii ty . V d mun khai bo khong thi giantr l 5s ta c th khai bo nh sau:

W#16#1050 hoc W#16#2005. Trong , ch s 1 hoc 2 l phn gii c quy nh theo bng sau:

Figure 2.19

Cn ba ch s ng sau l gi tr t. Nh vy, trong v d trn vi cng mt gi tr thi gian tr 5s tac th t c phn gii l 100ms hoc 1s.

Ngay ti thi im kch Timer, gi tr PV c chuyn vo thanh ghi 16 bits ca Timer T-Word ( gil thanh ghi CV- Curren value- gi tr tc thi). Timer s ghi nh khong thi gian tri qua k t khi kchbng cch gim dn mt cch tng ng ni dung thanh ghi CV. Nu ni dung thanh ghi CV tr v bng 0th Timer t c thi gian mong mun T v iu ny c bo ra ngoi bng cch thay i trng thitn hiu u ra Y(t). Vic thng bo ra ngoi bng cch i trng thi tn hiu du ra Y(t) nh th no cnph thuc vo loi Timer c s dng.

Bn cnh sn ln ca tn hiu u vo U(t), Timer cn c th kch bng sn ln ca tn hiu kch chng c tn l tn hiu ENABLE nu nh ti thi im c sn ln ca tn hiu ENABLE, tn hiu u voU(t) c gic l "1".

Tng loi Timer c nh s t 0 n 255 (tu thuc vo tng loi CPU). Mt Timer c t tnl Tx, trong x l s hiu ca Timer ( 0


69/137

63

xa tc thi trng thi ca T-word v T-bit ngi ta s dng mt tn hiu reset Timer. Ti thi imsn ln ca tn hiu ny gi tr T-Word v T-bit ng thi c gi tr bng 0 tc l thanh ghi tc thi CVc t v 0 v tn hiu u ra cng c trng thi Logic l "0". Trong thi gian tn hiu Reset c gi trlogic l "1" Timer s khng lm vic.

2.3.3.2 Khai bo s dng

Cc tn hiu iu khin cho mt b Timer phi c khai bo bao gm cc bc sau:- Khai bo tn hiu ENABLE nu mun s dng tn hiu ch ng kch.- Khai bo tn hiu u vo U(t).- Khai bo thi gian tr mong mun TV.- Khai bo loi Timer c s dng (SP, SE, SD, SS, SF).- Khai bo tn hiu xo Timer nu mun s dng ch Reset ch ng.Trong cc bc trn th bc 1 v 5 c th b qua.Dng d liu vo / ra ca b Timer:S : BOOL BI :WORDTW : S5TIME BCD : WORD

R : BOOL Q: BOOL

2.3.3.2.1 B thi gian SP: Khai bo

Figure 2.20

Nguyn l lm vicTi thi im sn ln ca tn hiu vo SET thi gian s c tnh ng thi gi tr Logic u ra l

"1". Khi thi gian t kt thc gi tr u ra cng tr v 0.


70/137


Figure 2.21

Khi c tn hiu RESET (R) thi gian tnh lp tc tr v 0 v tn hiu u ra cng gi tr l "0".V d: Vit chng trnh iu khin ng c khng ng b 3 pha i ni Y/, hot ng theo nguyntc sau: n nt Start kha K1 c in cp in cho h thng, ng thi K2 cng c in ng c hotng ch Y, sau thi gian 5s kha K3 c in ng c hot ng ch . n nt Stop h thng dng


71/137

65

2.3.3.2.2 B thi gian SE: Khai bo

Figure 2.22

Nguyn l lm vicTi thi im sn ln ca tn hiu vo SET cui cng b thi gian c thit lp v thi gian s c

tnh ng thi gi tr Logic u ra l "1". Kt thc thi gian t tn hiu u ra s tr v 0.Khi c tn hiu RESET (R) thi gian tnh lp tc tr v 0 v tn hiu u ra cng gi tr l "0".


72/137


Figure 2.23

V d: Vit chng trnh iu khin bng n hot ng nh sau: n nt S n sng sau thi gian 10sbng n t tt.


73/137

67

2.3.3.2.3 B thi gian SD: Khai bo

Figure 2.24

Nguyn l lm vicTi thi im sn ln ca tn hiu vo SET b thi gian c thit lp v thi gian s c tnh. Kt

thc thi gian t tn hiu u ra s c gi tr l "1". Khi tn hiu u vo kch S l "0" u ra cng lptc tr v "0" ngha l tn hiu u ra s khng c duy tr khi tn hiu kch c gi tr l "0".


74/137


75/137

69

2.3.3.2.4 B thi gian SS: Khai bo

Figure 2.26

Nguyn l lm vicTi thi im sn ln ca tn hiu vo SET b thi gian c thit lp v thi gian s c tnh. Kt

thc thi gian t tn hiu u ra s c gi tr 1 gi tr ny vn duy tr ngay c khi tn hiu u vo kch Sc gi tr l 0. Khi c tn hiu RESET (R) thi gian tnh lp tc tr v 0 v tn hiu u ra cng gi tr l"0".

V d: Mt bng n D c bt theo yu cu sau: n nt S1 sau 5s bng n sng, tt n bng ntn S2


76/137


Figure 2.27

2.3.3.2.5 B thi gian SF: Khai bo

Figure 2.28


77/137

71

Nguyn l lm vic

Figure 2.29

Ti thi im sn ln ca tn hiu vo SET b thi gian c thit lp. Tn hiu u ra c gi tr l 1.Nhng thi gian s c tnh thi im sn xung cui cng ca tn hiu u vao SET(S). Kt thc thigian t tn hiu u ra s tr v 0.

Khi c tn hiu RESET (R) thi gian tnh lp tc tr v 0 v tn hiu u ra cng gi tr l "0".V d: Mt ng c c iu khin hot ng theo nguyn tc sau: Bt cng tc S 1 ng c hot ng,

ng c dng li sau 5s khi tt cng tc S1 hoc dng li ngay khi n nt S2


78/137


2.3.4 Cc hm so snh6

2.3.4.1 Hm so snh s nguyn 16 bits: Khai bo

Figure 2.30

Khi thc hin chc nng so snh bng nhauC cc dng so snh hai s nguyn 16 bits nh sau:- Hm so snh bng nhau gia hai s nguyn 16 bits: ==- Hm so snh khc nhau gia hai s nguyn 16 bits: - Hm so snh ln hn gia hai s nguyn 16 bits: >- Hm so snh nh hn gia hai s nguyn 16 bits: =

- Hm so snh nh hn hoc bng nhau gia hai s nguyn 16 bits:


79/137

73

2.3.4.2 Hm so snh s nguyn 32 bits

Figure 2.31

Khi thc hin chc nng so snh bng nhauC cc dng so snh hai s nguyn 32 bits nh sau:- Hm so snh bng nhau gia hai s nguyn 32 bits: ==- Hm so snh khc nhau gia hai s nguyn 32 bits: - Hm so snh ln hn gia hai s nguyn 32 bits: >- Hm so snh nh hn gia hai s nguyn 32 bits: =- Hm so snh nh hn hoc bng nhau gia hai s nguyn 32 bits:


80/137


Cc dng so snh hai s thc 32 bits nh sau :- Hm so snh bng nhau gia hai s thc 32 bits: ==- Hm so snh khc nhau gia hai s thc 32 bits: - Hm so snh ln hn gia hai s thc 32 bits: >- Hm so snh nh hn gia hai s thc 32 bits: =- Hm so snh nh hn hoc bng nhau gia hai s thc 32bits:


81/137

75

2.3.5.1.2 Tr 2 s nguyn

Figure 2.34

D liu vo raEN: BOOL IN1: INTIN2 :INT OUT: INT ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin tr hai s nguyn 16 bits MW0 vi MW2.

Kt qu c ct vo MW10.Trong trng hp tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.

2.3.5.1.3 Nhn 2 s nguyn

Figure 2.35

D liu vo raEN: BOOL IN1: INTIN2 :INT OUT: INT ENO : BOOL


82/137


Khi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin nhn hai s nguyn 16 bits MW0 viMW2. Kt qu c ct vo MW10.

Trong trng hp tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.

2.3.5.1.4 Chia 2 s nguyn

Figure 2.36

Khi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin chia hai s nguyn 16 bits MW0 vi MW2.Kt qu c ct vo MW10.


2.3.5.2 Nhm lm vic vi s nguyn 32 bits

2.3.5.2.1 Cng 2 s nguyn

Figure 2.37

D liu vo ra


83/137

77

EN: BOOL IN1: DINTIN2 :DINT OUT: DINT ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin cng hai s nguyn 32 bits MD0 vi MD4.

Kt qu c ct vo MD10.Trong trng hp tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.

2.3.5.2.2 Tr 2 s nguyn

Khi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin tr hai s nguyn 32 bits MD0 vi MD4.Kt qu c ct vo MD10.


Figure 2.38

D liu vo raEN: BOOL IN1: DINTIN2 :DINT OUT: DINT ENO : BOOL


84/137


2.3.5.2.3 Nhn 2 s nguyn

Figure 2.39

D liu vo raEN: BOOL IN1: DINTIN2 :DINT OUT: DINT ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin nhn hai s nguyn 32 bits MD0 vi

MD4. Kt qu c ct vo MD10.Trong trng hp tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.

2.3.5.2.4 Chia 2 s nguyn

Figure 2.40

D liu vo raEN: BOOL IN1: DINT


85/137

79

IN2 :DINT OUT: DINT ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin chia hai s nguyn 32 bits MD0 vi MD4.

Kt qu c ct vo MD10.Trong trng hp tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.

2.3.5.3 Nhm lm vic vi s thc

2.3.5.3.1 Cng 2 s thc

Khi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin cng hai s thc MD0 + MD4. Kt qu cct vo MD10.


Figure 2.41

D liu vo raEN: BOOL IN1: REALIN2 : REAL OUT: REAL ENO : BOOL

2.3.5.3.2 Tr 2 s thc

Khi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin tr hai s thc MD0 - MD4. Kt qu cct vo MD10.



86/137


Figure 2.42

D liu vo raEN: BOOL IN1: REALIN2 : REAL OUT: REAL ENO : BOOL

2.3.5.3.3 Nhn 2 s thc

Figure 2.43

D liu vo raEN: BOOL IN1: REALIN2 : REAL OUT: REAL ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin nhn hai s thc MD0 . MD4. Kt qu

c ct vo MD10.Trong trng hp tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.


87/137

81

2.3.5.3.4 Chia 2 s thc

Figure 2.44

D liu vo raEN: BOOL IN1: REALIN2 : REAL OUT: REAL ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin chia hai s thc MD0 : MD4. Kt qu

c ct vo MD10.Trong trng hp tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.

2.3.5.4 Mt s hm khc

2.3.5.4.1 Hm ly gi tr tuyt i ABS

Figure 2.45


88/137


D liu vo raEN: BOOL OUT: REALIN : REAL ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin chc nng ly gi tr tuyt i ca MD8

ri ct vo MD12Khi tn hiu vao I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.

2.3.5.4.2 Hm SIN, COS, TAN, ASIN, ACOS, ATAN

Figure 2.46

D liu vo raEN: BOOL OUT: REALIN : REAL ENO : BOOLKhi tn hiu vo I0.0 = 1 u ra Q4.0 = 1 v hm s thc hin chc nng tnh SIN, COS, TAN, ASIN,

ACOS, ATAN ca MD0 ri ct vo MD10.Khi tn hiu vo I0.0 = 0 u ra Q4.0 = 0 v hm s khng thc hin chc nng.


89/137

83

2.3.6 Hm di chuyn d liu8

2.3.6.1 Khi chuyn d liu: Khai bo

Figure 2.47

Nguyn l hot ngKhi c tn hu kch I0.0 khi MOVE c thit lp, tn hiu u ra ENO l Q4.0 =1. ng thi s liu

u vo IN l MW0 c Copy sang u ra OUT l MW2.Khi tn hiu kch I0.0 = 0 tn hiu u ra Q4.0 = 0.Trong trng hp mun thay i s liu trong b nh (tc l thay i gi tr trong MW2) ta c th

khng cn s dng tn hiu kch I0.0.V d: Mt bng n c hot ng theo nguyn tc sau: Nu n nt S1 n sng 5s, nu n nt S2

n sng 10s, n tt khi n nt S3

2.3.6.2 Cc b ghi dch v quay s liu trn thanh ghi

2.3.6.2.1 Dch phi s nguyn 16 bits: Khai bo

Khi tn hiu kch I0.0 = 1 Khi s thc hin chc nng dich chuyn sang phi s liu trong thanh ghi. ngthi tn hiu ra ti ENO l Q4.0 c gi tr l 1.

S liu a vo ti IN l MW0S bit s dich chuyn l MW2 ( ti chn N)Kt qu sau khi dch c ct vo MW4.Trn s cho ta thy kt qu ca b dch phi 4 bit.



90/137


Figure 2.48

Figure 2.49


91/137

85

2.3.6.2.2 Dch phi s nguyn 32 bits: Khai bo

Figure 2.50

Khi tn hiu kch I0.0 = 1. Khi s thc hin chc nng dich chuyn sang phi s liu trong thanh ghi. ngthi tn hiu ra ti ENO l Q4.0 c gi tr l 1.

S liu a vo ti IN l MD0S bit s dch chuyn l MW2 (ti chn N). Kt qu sau khi dch c ct vo MW4.Trn s cho ta thy kt qu ca b dch phi 4 bit.

2.3.6.2.3 Dch tri 16 bits: Khai bo

Nguyn l hot ngKhi c tn hiu kch I0.0 = 1 tn hiu ra Q4.0 c thit lp v c gi tr 1.D liu u vo MW0 c dch sang tri vi s bit c t ti chn N (MW2). Kt qu sau khi dch

c ghi vo MW4.

Figure 2.51: Gin thi gian b dch tri 6 v tr


92/137


Figure 2.52

2.3.6.2.4 Quay tri s 32 bits: Khai bo

Figure 2.53


93/137


94/137


Figure 2.56

2.3.7 Hm logic thc hin trn thanh ghi9

2.3.7.1 Hm AND 2 s 16 bits: Khai bo

Figure 2.57

Nguyn l hot ngHm s thc hin chc nng nhn hai s nh phn tai u vo IN1 v u vo IN2 kt qu c ct

OUT ( MW2) khi c tn hiu kch ti chn EN (I0.0 =1).Tn hiu u ra ENO (Q4.0 = 1) khi hm thc hin chc nng.-V d:IN1 = 0101010101010101 S th nht



95/137

89

IN2 = 0100000000001111 S th 2OUT = 0100000000000101 Kt qu

2.3.7.2 Hm OR 2 s 16 bits: Khai bo

Figure 2.58

Nguyn l hot ngHm s thc hin chc nng OR hai s nh phn tai u vo IN1 v u vo IN2 kt qu c ct

OUT ( MW2) khi c tn hiu kch ti chn EN (I0.0= 1).Tn hiu u ra ENO (Q4.0 = 1) khi hm thc hin chc nng.-V d:

IN1 = 0101010101010101 S th nhtIN2 = 0000000000001111 S th 2OUT = 0101010101011111 Kt qu


96/137


2.3.7.3 Hm XOR 2 s 16 bits: Khai bo

Figure 2.59

Nguyn l hot ngHm s thc hin chc nng XOR hai s nh phn tai u vo IN1 v u vo IN2 kt qu c ct

OUT khi c tn hiu kch ti chn EN.Tn hiu u ra ENO khi hm thc hin chc nng.V d:IN1 = 0101010101010101 S th nhtIN2 = 0000000000001111 S th 2OUT = 0101010101011010 Kt qu

2.3.7.4 Hm AND 2 t kp: Khai bo

Figure 2.60

EN(I0.0): BOOL IN2 : DWORD


97/137

91

IN1 : DWOED OUT : DWORD ENO : BOOLNguyn l hot ngHm s thc hin chc nng AND hai s nh phn ti u vo IN1 v u vo IN2 kt qu c ct

OUT khi c tn hiu kch ti chn EN.Tn hiu u ra ENO khi hm thc hin chc nng.V d:IN1 = 0101010101010101 0101010101010101IN2 = 0000000000000000 0000111111111111OUT = 000000000000000 0000010101010101

2.3.7.5 Hm OR 2 t kp: Khai bo

Figure 2.61

EN(I0.0): BOOL IN2 : DWORDIN1 : DWOED OUT : DWORD ENO : BOOLNguyn l hot ngHm s thc hin chc nng OR hai s c di 2 t ti u vo IN1 v u vo IN2 kt qu c ct

OUT khi c tn hiu kch ti chn EN.Tn hiu u ra ENO khi hm thc hin chc nng.V d:IN1 = 0101010101010101 0101010101010101IN2 = 0000000000000000 0000111111111111OUT = 0101010101010101 0101111111111111


98/137


2.3.7.6 Hm XOR 2 t kp: Khai bo

Figure 2.62

EN(I0.0): BOOL IN2: DWORD

IN1: DWORD OUT: DWORD ENO: BOOL

Table 2.1

Nguyn l hot ngHm s thc hin chc nng XOR hai s c di 2 t ti u vo IN1 v u vo IN2 kt qu c

ct OUT khi c tn hiu kch ti chn ENTn hiu u ra ENO khi hm thc hin chc nng.V d:IN1 = 0101010101010101 0101010101010101IN2 = 0000000000000000 0000111111111111OUT = 0101010101010101 0101101010101010

2.3.8 Lnh lm vic vi tn hiu tng t10

2.3.8.1 Cc dng tn hiu tng t

Nu tn hiu s (digital signals) l loi tn hiu ch c 2 mc 0 v 1 tng ng vi 0V v 24V th tn hiutng t c th nhn bt c gi tr no trong mt di xc nh. x l tn hiu tng t, cc i lng

vt l nh: nhit , lu lng, tc t cm bin s c chuyn i thnh tn hiu in nh dng in,in p, in tr.Sau tn hiu ny c gi ti PLC x l. Tn hiu ny c chuyn i A/D. Thng thng b

chuyn i A/D dng trong cc module tng t ca PLC l loi 8bit hoc 12 bit.

2.3.8.2 . Cc cu lnh x l tn hiu tng t

- Kiu gi tr u vo/ ra tng t : WordLnh c v ghi:



99/137


100/137



101/137

Chng 3

Chng 3 : Ngn ng lp trinh Step 7

3.1 CI T STEP 71

Step 7 l mt phn mm h tr, cho php :- Khai bo cu hnh cng cho mt trm PLC thuc h Simatic S7-300/400.- Xy dng cu hnh mng gm nhiu trm PLC S7-300/400 cng nh th tc truyn thng gia chng.- Son tho v ci t chng trnh iu khin cho 1 hoc nhiu trm.- Gim st vic thc hin chng trnh iu khin trong mt trm PLC v g ri chng trnh.Ngoi ra Step 7 cn c c mt th vin y vi cc hm chun hu ch, phn tr gip Online rt

mnh c kh nng tr li mi cu hi ca ngi s dng v cch s dng Step 7, v c php lnh trong lptrnh, v xy dng cu hnh cng ca mt trm cng nh ca mt mng gm nhiu trm PLC.

Ch : iu kin ci t thnh cng phn mm STEP7 vo my tnh l i hi cu hnh my tithiu : CPU 80586, 8MRAM , cng trng 90MB v c card VGA

Ti vit nam hin c rt nhiu phin bn ca b phn mm gc ca Step7. ang c s dng nhiunht l phin bn (version) 4.2, 5.0, 5.1, 5.2, 5.3. Trong khi phin bn 4.2 kh ph hp cho nhng PC c cu

hnh trung bnh (CPU 80586, 90MB cn trng trong cng, mn hnh VGA) nhng li i hi tuyt i cbn quyn. Trong khi phin bn 5.0 v 5.1 mc d i hi my tnh c cu hnh mnh nhng li khng ihi bn quyn mt cch tuyt i, ngha l phin bn ny vn lm vic mt mc hn ch khi khng c bnquyn. Phn ln cc a gc ca Step7 u c kh nng t ci t chng trnh (autorun). Bi vy ch cncho a vo CD v thc hin theo ng ch dn hin trn mn hnh. Ta c th ch ng thc hin vic cit bng cch gi chng trnh Setup.exe c trn a. Cng vic ci t, v c bn khng khc nhiu so vivic ci t cc phn mm ng dng khc, tc l cng bt u bng vic chn ngn ng ci t ( mc nhl ting Anh), chn th mc t trn cng (mc nh l C:\simens), kim tra dung lng cn li trn cng, chn ngn ng s c s dng trong qu trnh lm vic vi Step7 sau ny.


95


102/137

96 CHNG 3. CHNG 3 : NGN NG LP TRINH STEP 7

Figure 3.1

Khai bo m hiu sn phm: m hiu sn phm lun i km vi sn phm v c in ngay trn a chab ci Step7. Khi trn mn hnh xut hin ca s yu cu cho tit m hiu sn phm, ta phi in y vo tt c cc th mc ca ca s , k c a ch ngi s dng sau n continue tip tc.

3.2 Son tho mt Project mi2

Khi nim Project khng n thun ch l chng trnh ng dng m rng hn bao gm tt c nhng glin quan n vic thit k phn mm ng dng iu khin, gim st mt hay nhiu trm PLC. Theokhi nim nh vy, trong mt Project s c:

1. Bng cu hnh cng v tt c cc module ca tng trm PLC.2. Bng tham s xc nh ch lm vic cho tng module ca mi trm PLC.3. Cc Logic block cha chng trnh ng dng ca tng trm PLC.4. Cu hnh ghp ni v truyn thng gia cc trm PLC.5. Cc ca s giao din phc v vic gim st ton b mng hoc gim st tng trm PLC ca mng.

y, trong khun kh phn mm Step7 ti ch gii thiu vic son tho mt Project gm cc phn 1,2,3.Nhng phn cn li bn c c th tham kho trong cun ti liu khc



103/137

97

3.2.1 Cc thao tc khai bo v m mt Project mi. khai bo mt Project, t mn hnh chnh ca Step 7 ta chn File-> New hoc kch chut ti biu tng"New Project/ Library".

Figure 3.2

Khi trn mn hnh s xut hin hp hi thoi nh hnh 3-6. G tn Project ri n phm OK v nhvy ta khai bo song mt Project mi. Ngoi ra ta cn c th chn ni Project s c ct ln a. Mcnh, ni ct s l th mc c quy nh khi ci t Step 7, y l th mc F: \S7_ projects.

Trong trng hp mun m mt Project c, ta chn File -> Open hoc kch chut ti biu tng"Open Project/ Library" t ca s chnh ca Step7 ri chn tn Project mun m t hp hi thoi c dngnh hnh 3-7. Cui cng n phm OK kt thc.


104/137

98 CHNG 3. CHNG 3 : NGN NG LP TRINH STEP 7

Figure 3.3

3.2.2 Xy dng cu hnh cng cho trm PLC.Sau khi khai bo xong mt Project mi, trn mn hnh s xut hin Project nhng dng rng (cha cg trong project), iu ny ta nhn bit c qua biu tng th mc bn cnh tn Project ging nh mtth mc rng ca Window.


105/137

99

Figure 3.4

Documents

Plc Hung Yen