Baigiang Plc

TI LIU HC TP PLC Copyright by Tuan Manh: 0915191501

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MC LC Chng 1: Gii thiu v PLC 1.1 Tng quan v PLC. 1.2 Cu trc v hot ng ca PLC. 1.3 Phn loi PLC 1.4 So snh PLC vi cc h iu khin khc. 1.5 Phm vi ng dng ca PLC. 1.6 Thit k h thng dng PLC. 1.7 Gii thiu PLC Siemens. Chng 2: PLC S7-200 2.1 Cu trc phn cng. 2.2 Hot ng ca PLC. 2.3 Cu trc b nh. 2.4 Phng php lp trnh. Chng 3: Tp lnh PLC S7-200 3.1 Cc lnh c bn. 3.2 Counter v Timer. 3.3 Lnh so snh. 3.4 Lnh v cng logic. 3.5 Lnh di chuyn ni dung MOVE 3.6 Lnh chuyn i d liu 3.7 Lnh tng gim 1 n v. 3.8 Lnh s hc 3.9 Lnh nhy v gi chng trnh con. 3.10 Truy cp ng h thi gian thc. Chng 4: Cu trc chng trnh PLC 4.1 Cu trc tun t. 4.2 Cu trc Automat. 4.3 Cu trc c chng trnh con. Chng 5: Phn mm lp trnh v m phng 5.1 Phn mm STEP 7-Micro/WIN4.0 5.2 Phn mm m phng S7-200.


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Chng 1: GII THIU V PLC 1.1 TNG QUAN V PLC: 1.1.1 Lch S Pht Trin: Thit b iu khin lp trnh u tin (programmable controller) c nhng nh thit k cho ra i nm 1968 (Cng ty General Motor - M). Tuy nhin, h thng ny cn kh n gin v cng knh, ngi s dng gp nhiu kh khn trong vic vn hnh h thng. V vy cc nh thit k tng bc ci tin h thng n gin, gn nh, d vn hnh, nhng vic lp trnh cho h thng cn kh khn, do lc ny khng c cc thit b lp trnh ngoi vi h tr cho cng vic lp trnh. n gin ha vic lp trnh, h thng iu khin lp trnh cm tay (Programmable Controller Handle) u tin c ra i vo nm 1969. iu ny to ra mt s pht trin tht s cho k thut iu khin lp trnh. Trong giai on ny cc h thng iu khin lp trnh (PLC) ch n gin nhm thay th h thng Relay v dy ni trong h thng iu khin c in. Qua qu trnh vn hnh, cc nh thit k tng bc to ra c mt tiu chun mi cho h thng, tiu chun l lp trnh dng gin hnh thang, k hiu l LAD. Trong nhng nm u thp nin 1970, nhng h thng PLC cn c thm kh nng khc, l s h tr bi nhng thut ton, vn hnh vi cc d liu cp nht. Mt khc, do s pht trin ca mn hnh dng cho my tnh nn vic giao tip gia ngi iu khin lp trnh cho h thng cng tr nn thun tin hn. S pht trin ca h thng phn cng v phn mm t nm 1975 cho n nay lm cho h thng PLC pht trin mnh m hn vi cc chc nng m rng: h thng ng vo/ra c th tng ln n 8.000 cng vo/ra, dung lng b nh chng trnh tng ln hn 128.000 t b nh (word of memory). Ngoi ra cc nh thit k cn to ra k thut kt ni vi cc h thng PLC ring l thnh mt h thng PLC chung, tng kh nng ca tng h thng ring l. Tc x l ca h thng c ci thin, chu k qut (scan) nhanh hn lm cho h thng PLC x l tt vi nhng chc nng phc tp s lng cng ra/vo ln. Trong tng lai h thng PLC khng ch giao tip vi cc h thng khc thng qua CIM (Computer Intergrated Manufacturing) iu khin cc h thng: Robot, Cad/Cam m cc nh thit k cn xy dng cc loi PLC vi cc chc nng iu khin thng minh gi l cc siu PLC (super PLC). 1.1.2 c im ca PLC: PLC (Programmable Logic Controller) l mt thit b iu khin lp trnh, cho php thc hin linh hat cc thut ton iu khin logic thng qua ngn ng lp trnh. PLC c s dng trong nhiu lp trnh ng dng khc nhau v c nhng li ch nh:

- PLC d dng thay thay i chng trnh iu khin thch ng mt yu cu mi m vn c th gi nguyn thit k phn cng, u ni dy

- PLC c th iu khin nhiu chc nng khc nhau t nhng thao tc n gin, lp li, lin tc n nhng thao tc i hi chnh xc, phc tp.

- PLC d dng hiu chnh chnh xc cng vic iu khin v x l nhanh chng cc lnh, t lnh logic n gin n cc lnh m (Counter), nh thi (time), chng trnh con (SBS) v.v

- Giao tip d dng vi cc thit b ngoi vi, cc module v cc thit b ph tr nh mn hnh hin th.

- C kh nng chng nhiu trong cng nghip.


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- Ngn ng lp trnh cho PLC n gin, d hiu. Vi nhng u im trn thit b PLC tr thnh thit b chnh trong vic iu khin cc thit b cng nghip. 1.2 CU TRC V HOT NG CA MT PLC: 1.2.1 Cu trc : Mt h thng iu khin lp trnh c bn phi gm c hai phn: Khi x l trung tm (CPU: Central Processing Unit : CPU) v h thng giao tip vo/ra (I/0).

Hnh 1.1 : S khi ca h thng iu khin lp trnh Khi x l trung tm (CPU) gm ba phn : B x l, H thng b nh v H thng ngun cung cp. Hnh 1.2 m t 3 thnh phn ca mt CPU.

Hnh 1.2 : S khi tng qut ca CPU

1.2.2 Hot ng ca PLC :

oc d lieu t ngoai vao

Read input1.

Thc hien chng trnhProgram excution

2.3. Truyen thong va t kiem tra loi

4. Chuyen d lieu t bo nh ao ieu khien thiet b ngoai vi

)(

( )

Hnh 1.3 :Mt vng qut ca PLC.


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PLC thc hin chng trnh theo chu trnh lp, mi vng lp c gi l vng qut. Mi vng qut bt u bng giai on c d liu t cc ng vo (contact, sensor, relay...) vo vng b m o, tip theo l giai on thc hin chng trnh. Trong tng vng qut, chng trnh c thc hin bng lnh u tin v kt thc ti lnh MEND. Sau giai an thc hin chng trnh l giai on truyn thng ni b v kim tra li. Vng qut c kt thc bng giai on chuyn cc ni dung ca b m o ti cc ng ra. Nh vy, ti thi im thc hin lnh vo/ra, lnh ny khng trc tip lm vic vi cng vo/ra m ch thng qua b m o ca cng trong vng tham s. Vic truyn thng gia b m o vi thit b ngoi vi trong giai an 1 v 4 l do CPU qun l. Khi gp lnh vo/ra ngay lp tc th h thng s cho dng mi cng vic khc, ngay c chng trnh x l ngt thc hin lnh ny trc tip vi cng vo/ra. Thng vic thc thi mt vng qut xy ra vi mt thi gian rt ngn, mt vng qut n (single scan) c thi gian thc hin t 1ms ti 100ms. Vic thc hin mt chu k qut di hay ngn cn ph thuc vo di ca chng trnh v c mc giao tip gia PLC vi cc thit b ngoi vi (mn hnh hin th).Vi x l c th c c tn hiu ng vo ch khi no tn hiu ny tc ng vi khong thi gian ln hn mt chu k qut th vi x l coi nh khng c tn hiu ny. Tuy nhin trong thc t sn xut, thng cc h thng chp hnh l cc h thng c kh nn tc qut nh trn c th p ng c cc chc nng ca dy chuyn sn xut. khc phc thi gian qut di, nh hng n chu trnh sn xut cc nh thit k cn thit k h thng PLC cp nht tc thi, cc h thng ny thng c p dng cho cc PLC ln c s lng I/O nhiu, truy cp v x l lng thng tin ln. - Ng vo: Ng vo thc l ng vo c cc mch in chuyn i lm cho tn hiu t bn ngoi sau khi qua b chuyn i ny s c mc logic 0, hoc 1 m vi x l nhn bit c. Nh vy, cc ng vo o dng lm vng nh. Ta ch c th dng ng vo thc kt ni vi cc tip im bn ngoi - Ng ra: PLC s dng hai gii php xut tn hiu l dng Relay v Transistor. Relay vi c im l ng ngt chm, tn nhiu khng gian lm cho kch thc ca PLC ln.

Hnh 1.4: Ng ra dng Relay

Transistor c hn ch v dng in ng ra, thng mc theo dng cc thu h.


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Hnh 1.5: Ng ra dng transistor

1.3 PHN LOI PLC: u tin l kh nng v gi tr cng nh nhu cu v h thng s gip ngi s dng chn nhng loi PLC no m h cn. Nhu cu v h thng c xem nh l mt nhu cu u tin, n gip ngi s dng bit cn loi PLC no v c trng ca tng loi d dng la chn.

Hnh 1.6: Phn loi PLC

Hnh 1.6 cho ta cc bc thang phn loi cc loi PLC v vic s dng PLC cho ph hp vi cc h thng thc t sn xut. Trong hnh ny ta c th nhn thy nhng vng chng ln nhau, nhng vng ny ngi s dng thng phi s dng cc loi PLC c bit nh: s lng cng vo/ra (I/O) c th s dng vng c s I/O thp nhng li c cc tnh nng c bit ca cc PLC vng c s lng I/O cao. Thng s dng cc loi PLC thuc vng chng ln nhm tng tnh nng ca PLC ng thi li gim thiu s lng I/O khng cn thit. Cc nh thit k phn PLC ra thnh cc loi sau: - Loi 1: Micro PLC (PLC siu nh). Micro PLC thng c ng dng trong cc dy chuyn sn xut nh, cc ng dng trc tip trong tng thit b n l (v d: iu khin bng ti nh. Cc PLC ny thng c lp trnh bng cc b lp trnh cm tay, mt vi micro PLC cn c kh nng hot ng vi tn hiu I/O tng t (analog). Cc tiu chuu ca mt Micro PLC nh sau:

32 ng vo/ra. S dng vi x l 8 bit. Thng dng thay th rle. B nh c dung lng 1K.


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Ng vo/ra l tn hiu s. C timers v counters. Thng c lp trnh bng cc b lp trnh cm tay.

- Loi 2: PLC c nh (Small PLC) Small PLC thng c dng trong vic iu khin cc h thng nh (v d: iu khin ng c, dy chuyn sn xut nh), chc nng ca cc PLC ny thng c gii hn trong vic thc hin chui cc mc logic, iu khin thay th rle. Cc tiu chun ca mt small PLC nh sau:

C 128 ng vo/ra (I/O). Dng vi x l 8 bit. Thng dng thay th cc role. Dng b nh 2K. Lp trnh bng ngn ng dng hnh thang (ladder) hoc lit k. C timers/counters/thanh ghi dch (shift registers). ng h thi gian thc. Thng c lp trnh bng b lp trnh cm tay.

Ch vng A trong s hnh 1.6. y dng PLC nh vi cc chc nng tng cng ca PLC c ln hn nh: thc hin c cc thut ton c bn, c th ni mng, cng vo ra c th s dng tn hiu tng t. - Loi 3: PLC c trung bnh (Medium PLC) PLC trung bnh iu khin c cc tn hiu tng t, xut nhp d liu, ng dng c nhng thut ton, thay i c cc c tnh ca PLC nh vo hot ng ca phn cng v phn mm (nht l phn mm) cc thng s ca PLC trung bnh nh sau:

C khong 1024 ng vo/ra (I/O). Dng vi x l 8 bit. Thay th rle v iu khin c tn hiu tng t. B nh 4K, c th nng ln 8K. Tn hiu ng vo ra l tng t hoc s. C cc lnh dng khi v ngn ng lp trnh l ngn ng cp cao. C timers/Counters/Shift Register. C kh nng x l chng trnh con (qua lnh JUMP). C cc lnh dng khi v ngn ng lp trnh l ngn ng cp cao. C timers/counters/Shift Register. C kh nng x l chng trnh con ( qua lnh JUMP). Thc hin cc thut ton (cng, tr, nhn, chia). Gii hn d liu vi b lp trnh cm tay. C ng tn hiu c bit module vo/ra. Giao tip vi cc thit b khc qua cng RS232. C kh nng hot ng vi mng. Lp trnh qua mn hnh my tnh d quan st.

- Loi 4: PLC c ln (large PLC). Large PLC c s dng rng ri hn do c kh nng hot ng hu hiu, c th nhn d liu, bo nhng d liu nhn Phn mm cho thit b iu khin cm tay c pht trin mnh hn to thun li cho ngi s dng. Tiu chun PLC c ln: Ngoi cc tiu chun nh PLC c trung, PLC c ln cn c thm cc tiu chun sau:

C 2048 cng vo/ra (I/O).


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Dng vi x l 8 bit hoc 16 bit. B nh c bn c dung lng 12K, m rng ln c 32K. Local v remote I/O. iu khin h thng rle (MCR: Master Control Relay). Chui lnh, cho php ngt (Interrupts). PID hoc lm vic vi h thng phn mm PID. Hai hoc nhiu hn cng giao tip RS 232. Ni mng.

D liu iu khin m rng, so snh, chuyn i d liu, chc nng gii thut ton m iu khin m rng (m nh phn, hexa ).

C kh nng giao tip gia my tnh v cc module. - Loi 5: PLC rt ln (very large PLC) Very large PLC c dng trong cc ng dng i hi s phc tp v chnh xc cao, ng thi dung lng chng trnh ln. Ngoi ra PLC loi ny cn c th giao tip I/O vi cc chc nng c bit, tiu chun PLC loi ny ngoi cc chc nng nh PLC loi ln cn c thm cc chc nng:

C 8192 cng vo/ra (I/O). Dng vi x l 16 bit hoc 32 bt. B nh 64K, m rng ln c 1M. Thut ton :+, -, *, /, bnh phng. D liu iu khin m rng: Bng m ASCII, LIFO, FIFO.

1.4 SO SNH PLC VI CC H THNG IU KHIN KHC: 1.4.1 PLC vi h thng iu khin bng rle: Vic pht trin h thng iu khin lp trnh dn thay th tng bc h thng iu khin bng rle trong cc qu trnh sn xut khi thit k mt h thng iu khin hin i, ngi k s phi cn nhc, la chn gia cc h thng iu khin lp trnh thng c s dng thay cho h thng iu khin bng r le do cc nguyn nhn sau: - Thay i chng trnh iu khin mt cch linh ng. - C tin cy cao. - Khng gian lp t thit b nh, khng chim nhiu din tch. - C kh nng a tn hiu iu khin ng ra ph hp: dng, p. - D dng thay i i vi cu hnh (h thng my mc sn xut) trong tng lai khi

c nhu cu m rng sn xut. c trng cho h thng iu khin chng trnh l ph hp vi nhng nhu cu nu trn, ng thi v mt kinh t v thi gian th h thng iu khin lp trnh cng vt tri hn h thng iu khin c (rle, contactor ). H thng iu khin ny cng ph hp vi s m rng h thng trong tng lai do khng phi thay i, loi b h thng dy ni gia h thng iu khin v cc thit b, m ch n gin l thay i chng trnh sao cho ph hp vi iu kin sn xut mi. 1.4.2 PLC vi my tnh c nhn: i vi mt my tnh c nhn, ngi lp trnh d nhn thy c s khc bit gia PC vi PLC, s khc bit c th bit c nh sau: My tnh khng c cc cng giao tip tip vi cc thit b iu khin, ng thi my tnh cng hot ng khng tt trong mi trng cng nghip.


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Ngn ng lp trnh trn my tnh khng phi dng hnh thang, my tnh ngoi vic s dng cc phn mm chuyn bit cho PLC, cn phi thng qua vic s dng cc phn mm khc lm chm i qu trnh giao tip vi cc thit b c iu khin. Tuy nhin qua my tnh, PLC c th d dng kt ni vi cc h thng khc, cng nh PLC c th s dng b nh (c dung lng rt ln) ca my tnh lm b nh ca PLC. 1.5 PHM VI NG DNG PLC: Hin nay PLC c ng dng thnh cng trong nhiu lnh vc sn xut c trong cng nghip v dn dng. T nhng ng dng iu khin cc h thng n gin, ch c chc nng ng m (ON/OFF) thng thng n cc ng dng cho cc lnh vc phc tp, i hi tnh chnh xc cao, ng dng cc thut ton trong qu trnh sn xut. Cc lnh vc tiu biu ng dng PLC hin nay bao gm: - Ha hc v du kh: nh p sut (du), bm du, iu khin h thng ng dn, cn

ng trong ngnh ha - Ch to my v sn xut: T ng ho trong ch to my, cn ng, qu trnh lp

t my, iu khin nhit l kim loi - Bt giy, giy, x l giy. iu khin my bm, qu trnh bt, cn, gia nhit - Thy tinh v phim nh: qu trnh ng gi, th nghim vt liu, cn ong, cc khu

hon tt sn phm, o ct giy . - Thc phm, ru bia, thuc l: m, kim tra sn phm, kim sot qu trnh sn

xut, bm (bia, nc tri cy ), cn ong, ng gi, ha trn - Kim loi: iu khin qu trnh cn, cun (thp), qui trnh sn xut, kim tra cht

lng sn phm. - Nng lng: iu khin nguyn liu (cho qu trnh t, x l trong cc

turbin ), cc trm cn hot ng tun t khai thc vt liu mt cch t ng (than, g, du m).

1.6 THIT K H THNG IU KHIN DNG PLC: thit k 1 chung trnh iu khin cho mt hot ng bao gm nhng bc sau: B1: Xc nh qui trnh cng ngh: Trc tin, ta phi xc nh thit b hay h thng no mun iu khin. Mc ch cui cng ca b iu khin l iu khin mt h thng hot ng. S vn hnh ca h thng c kim tra bi cc thit b u vo. N nhn tn hiu v gi tn hiu n CPU, CPU x l tn hiu v gi n n thit b xut iu khin s hot ng ca h thng nh lp trnh sn trong chng trnh. B2: Xc nh ng vo, ng ra: Tt c cc thit b xut, nhp bn ngoi u c kt ni vi b iu khin lp trnh. Thit b nhp l nhng contact, cm bin ... Thit b xut l nhng cun dy, van in t , motor, b hin th. Sau khi xc nh tt c cc thit b xut nhp cn thit, ta nh v cc thit b vo ra tng ng cho tng ng vo, ra trn PLC trc khi vit chng trnh. B3: Vit chng trnh, v sa li: Khi vit chng trnh theo s hnh bc thang (ladder ) phi theo s hot ng tun t tng bc ca h thng, hoc theo dng STL. Sau tin hnh sa li nu c. B4: Np chng trnh vo b nh:


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Chng ta c th cung cp ngun cho b iu khin c lp trnh thng qua cng I/O. Sau np chng trnh vo b nh thng qua my tnh c cha phn mm lp trnh hnh thang. Sau khi np xong, kim tra li bng hm chun on. Nu c m phng ton b hot ng ca h thng chc chn rng chung trnh hot ng tt. B5: Chy chng trnh: Trc khi nhn nt Start, phi chc chn rng cc dy dn ni cc ng vo, ra n cc thit b nhp, xut c ni ng theo ch nh. Lc PLC mi bt u hot ng thc s. Trong khi chy chng trnh, nu b li th my tnh s bo li , ta phi sa li cho n khi n hot ng an ton Sau y l lu phng php thit k b iu khin:


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Xc nh yu cu ca h thng iu khin

V lu chung ca h thng iu khin

Lit k tt c cc ng ra, ng vo ni tng i n cc cng I/O ca PLC

Chuyn lu sang s hnh thang

Np lp trnh s hnh thang thit k cho PLC

M phng chng trnh v sa li phn mm

Hiu chnh chng trnh cho ph hp

Kt ni ton b thit b vo, ra vi PLC

Kim tra tt c cc tip im vo, ra

Chng trnh OK


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Hnh 1.7: Lu phng php thit k b iu khin

1.7 CU TRC C TNH CA PLC SIEMENS: Vit Nam hin nay c rt nhiu hng cung cp thit b PLC: Siemens, Omron, Panasonic, Mishumitshi, Tuy nhin do c th ca Khoa in t nn ti liu ny ch tp trung vo PLC ca hng Siemens. Tt c cc PLC u c thnh phn chnh l: - Mt b nh chng trnh RAM bn trong (c th m rng thm mt s b nh

ngoi EPROM). - Mt b vi x l c cng giao tip dng cho vic ghp ni vi PLC. - Cc Module vo /ra. Bn cnh , mt b PLC hon chnh cn i km thm mt n v lp trnh bng tay hay bng my tnh. Hu ht cc n v lp trnh n gin u c RAM cha chng trnh. Nu n v lp trnh l loi xch tay th 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. Cc n v lp trnh ni vi PLC qua cng RS232, RS485.

Chy th chng trnh

Hiu nh li phn mm

Np chng trnh vo EPROM

Lp h s h thng cho tt c cc bn v

END

Chng Trnh OK


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Chng 2: GII THIU PLC S7-200 2.1 CU TRC PHN CNG: S7-200 l thit b iu khin logic lp trnh loi nh ca hng Siemens (c), c cu trc theo kiu module v c cc module m rng. Cc module ny c s dng cho nhiu ng dng lp trnh khc nhau. Hnh dng bn ngoi ca PLC S7-200 c m t nh hnh 2.1.

Hnh 2.1: B iu khin lp trnh S7-200 CPU 214

Cc c im v thng s ca cc loi PLC S7-200 khc nhau c gii thiu trong bng bn di:

c trng CPU 221 CPU 222 CPU 224 CPU 226 Kch thc(mm) 90x80x62 90x80x62 120.5x80x62 190x80X62 B nh chng trnh 2048 words 2048words 4096words 4096words B nh d liu 1024 words 1024words 2560words 2560words Cng logic vo 6 8 14 24 Cng logic ra 4 6 10 16 Modul m rng none 2 7 7 Digital I/O cc i 128/128 128/128 128/128 128/128 Analog I/O cc i none 16In/16Out 32In/32Out 32In/32Out B m (Counter) 256 256 256 256 B nh th (Timer) 256 256 256 256 Tc thc thi lnh 0.37s 0.37s 0.37s 0.37s Kh nng lu tr khi mt in

50 gi 50 gi 190 gi 190 gi

Q0.0 Q0.1 Q0.2 Q0.3 Q0.4 Q0.5 Q0.6 Q0.7

I1.0 I1.1 I1.2 I1.3 I1.4 I1.5

I0.0 I0.1 I0.2 I0.3 I0.4 I0.5 I0.6 I0.7

SF RUN STOP

SIEMENS SIMATIC S7 - 200

Cc cng vo Cng truyn thng

Cc cng ra

Q1.0 Q1.1


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2.1.1 Cc n bo: - SF (n ): n SF (System Falu bo hiu h thng b hng. - RUN (n xanh): n xanh RUN ch nh PLC ang ch lm vic v thc

hin chng trnh c np vo trong my. - STOP (n vng): n vng STOP ch nh rng PLC ang ch dng chng

trnh v ang thc hin li 2.1.2 u vo: - Kiu u vo IEC 1131-2. - Tm in p mc logic 1: 15-30 VDC, dng nh nht 4 mA; 35VDC thi gian

tc thi 500ms. - Trng thi mc logic 1 chun: 24 VDC, 7mA. - Trng thi mc logic 0: Ti a 5 VDC, 1mA. - p ng thi gian ln nht cc chn I0.0 n I1.5: c th chnh t 0,2 n 8,7 ms

mc nh 0,2 ms. - Cc chn t I0.6 n I1.5 c s dng bi b m tc cao HSC1 v HSC2

30us n 70us. - S cch ly v quang 500VAC.1 min. 2.1.3 u ra: - Kiu u ra: Relay hoc Transistor. - Tm in p: 24.4 n 28.8 VDC. - Dng ti ti a: 2A/ im; 8A/common. - Qu dng: 7A vi contact ng. - in tr cch ly: nh nht 100 M. - Thi gian chuyn mch: ti a 10 ms. - Thi gian s dng: 10.000.000 vi cng tc c kh; 100.000 vi tc ti. - in tr cng tc: ti a 200 m. - Ch bo v ngn mch: khng c. 2.1.4 Ngun cung cp: - in p cp ngun: 20.4 n 24.8 VDC - Dng vo max load: 900mA ti 24 VDC - Cch ly in ng vo: Khng c - Thi gian duy tr khi mt ngun: 10ms 24 VDC - Cu ch bn trong: 2A, 250V 2.1.5 Ngun cp cho sensor: - Tm in p ra: 15.4 n 28.8 VDC - Dng ra ti a: 280mA - gn sng: Ging nh ngun cp vo - Cch ly: khng c 2.1.6 Ch lm vic: PLC c 3 ch lm vic: - RUN: cho php PLC thc hin chng trnh tng b nh, PLC s chuyn t RUN

sang STOP nu trong my c s c hoc trong chng trnh gp lnh STOP. - STOP: Cng bc PLC dng chng trnh ang chy v chuyn sang ch

STOP. - TERM: Cho php my lp trnh t quyt nh ch hot ng cho PLC hoc

RUN hoc STOP.


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2.1.7 Cng truyn thng: S7-200 s dng cng truyn thng ni tip RS485 vi phch ni 9 chn phc v cho vic ghp ni vi thit b lp trnh hoc vi cc trm PLC khc. Tc truyn cho my lp trnh kiu PPI (Point to Point Interface) l 9600 bauds. Tc truyn cung cp ca PLC theo kiu t do l 300 38.400 bauds.

Hnh 2.2: S chn ca cng truyn thng ghp ni S7-200 vi cc my lp trnh PG 702 hoc vi cc loi my lp trnh kiu h PG7xx c th ni thng qua MPI. Cp i km theo my lp trnh. ghp S7-200 vi cc my tnh PC qua cng RS-232 cn c cp ni PC/PPI vi b chuyn di RS232/RS485, theo hnh v 2.3.

Hnh 2.3: Ghp ni S7-200 vi my tnh qua cng RS232

Chn Chc nng 1 GND

2 24 VDC

3 Tn hiu A ca RS485 ( RxD/TxD+)

4 RTS ( theo mc TTL)

5 GND

6 +5 VDC

7 Ngun cp 24 VDC 120mA max

8 Tn hin B RS485 (RxD/TxD-)

9 chn la cch giao tip

5 4 3 1 2

9 8 7 6


TRANG - 15

2.1.8 M rng cng vo ra: C th m rng ng vo/ra ca PLC bng cch ghp ni thm vo PLC cc modul m rng v pha bn phi ca CPU (CPU 214 c th ghp nhiu nht 7 modul), lm thnh mt mc xch, bao gm cc modul c cng kiu. Cc modul m rng s hay tng t u chim ch trong b m, tng ng vi s u vo/ ra ca cc module. Sau y l mt v d v cch t a ch cho cc module m rng :

CPU MODUL 0 (4vo/4ra)

MODUL 1 (8 vo)

MODUL 2 ( 3 vo analog 1 ra analog)

MODUL 3 (8 ra)

MODUL 4 (3 vo analog 1 ra analog)

I0.0 Q0.0 I0.1 Q0.1 I0.2 Q0.2 I0.3 Q0.3 I0.4 Q0.4 I0.5 Q0.5 I0.6 Q0.6 I0.7 Q0.7 I1.1 Q1.0 I1.2 Q1.1 I1.3 I1.4 I1.5

I2.0 I2.1 I2.2 I2.3 Q2.0 Q2.1 Q2.2 Q2.3

I3.0 I3.1 I3.2 I3.3 I3.4 I3.5 I3.6 I3.7

AIW0 AIW2 AIW4 AQW0

Q3.0 Q3.1 Q3.2 Q3.3 Q3.4 Q3.5 Q3.6 Q3.7

AIW8 AIW10 AIW12 AQW4

2.2 NGUYN L HOT NG: 2.2.1 n V X L Trung Tm: CPU iu khin cc hot ng bn trong PLC. B x l s c v kim tra chng trnh c cha trong b nh, sau s thc hin th t tng lnh trong chng trnh, s ng hay ngt cc u ra. Cc trng thi ng ra y c pht ti cc thit b lin kt thc thi. V ton b cc hot ng thc thi u ph thuc vo chng trnh iu khin c lu gi trong b nh. 2.2.2 H Thng Bus: 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.


TRANG - 16

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 hay song song. Nu mt modul u vo nhn c a ch ca n trn Address Bus, n s chuyn tt c trng thi u vo ca n vo Data Bus. Nu mt a ch byte ca 8 u ra xut hin trn Address Bus, modul u ra tng ng s nhn c d liu t Data bus. Control Bus s chuyn cc tn hiu iu khin vo theo di chu trnh hot ng ca PLC Cc a ch v s liu c chuyn ln cc Bus tng ng trong mt thi gian hn ch. H thng Bus s lm nhim v trao i thng tin gia CPU, b nh v I/O . Bn cch , CPU c cung cp mt xung Clock c tn s t 18 MHZ. Xung ny quyt nh tc hot ng ca PLC v cung cp cc yu t v nh thi, ng h ca h thng. 2.2.3 B Nh: PLC thng yu cu b nh trong cc trng hp: - Lm b nh thi cho cc knh trng thi I/O. - Lm b m 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 nh s, nhng s ny chnh l a ch trong b nh . a ch ca tng nh s c tr n bi mt b m a ch 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 qu trnh 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, tu 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 xo b ni

dung bt k lc no. Ni dung ca RAM s b mt nu ngun in nui b mt . trnh tnh trng ny cc PLC u c trang b mt pin kh, c kh nng cung cp nng lng d tr cho RAM t vi thng n vi nm. Trong thc t RAM c dng khi to v kim tra chng trnh. Khuynh hng hin nay dng CMOSRAM nh kh nng tiu th nng lng thp v tui th ln.

- EPROM (Electrically Programmable Read Only Memory) l b nh m ngi s dng bnh thng ch c th c ch khng ghi ni dung vo c. Ni dung ca EPROM khng b mt khi mt ngun, n c gn sn trong my, c nh sn xut np v cha h iu hnh sn. Nu ngi s dng khng mun m rng b nh th ch dng EPROM gn bn trong PLC. Trn PG (Programmer) c sn ch ghi v xo EPROM.

Mi trng ghi d liu th ba 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 mt thi gian di. Kch thc b nh: - Cc PLC loi nh c th cha t 300 1000 dng lnh tu 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.


TRANG - 17

Hnh minh ha hot ng ca PLC khi ghp ni vi thit b ngoi vi.


TRANG - 18

2.2.4 Cc ng vo ra I/O: Cc ng tn hiu t b cm bin c ni vo cc module vo (cc u vo ca PLC), cc c cu chp hnh c ni vi cc module ra (cc u ra ca PLC). Hu ht cc PLC c in p hot ng bn trong l 5V, tn hiu x l l 12/24VDC hoc 100/240VAC. Mi n v I/O c duy nht mt a ch, cc hin th trng thi ca cc knh I / O c cung cp bi cc n LED trn PLC, iu ny lm cho vic kim tra hot ng nhp xut tr nn d dng v n gin. B x l c v xc nh cc trng thi u vo (ON, OFF) thc hin vic ng hay ngt mch u ra . 2.2.5 Hot ng ca PLC: PLC thc hin chng trnh theo chu trnh lp. Mi vng lp c gi l vng qut (scan), theo hnh 2.4. Mi vng qut c bt u bng giai on c d liu t cc cng vo vng b m o, tip theo l giai on thc hin chng trnh. Trong tng vng qut, chng trnh c thc hin bng lnh u tin v kt thc ti lnh kt thc (MEND). Sau giai on thc hin chng trnh l giai on truyn thng ni b v kim tra li. Vng qut c kt thc bng giai on chuyn cc ni dung ca b m o ti cc cng ra.

oc d lieu t ngoai vao

Read input1.

Thc hien chng trnhProgram excution

2.3. Truyen thong va t kiem tra loi

4. Chuyen d lieu t bo nh ao ieu khien thiet b ngoai vi

)(

( )

Hnh 2.4: Vng qut trong S7-200 Nh vy, ti thi im thc hin lnh vo/ra, thng thng lnh khng lm vic trc tip vi cng vo ra m ch thng qua b m o ca cng trong vng nh tham s. Vic truyn thng gia b m o vi ngoi vi trong cc giai on 1 v 4 do CPU qun l. Khi gp lnh vo/ra ngay lp tc th h thng s cho dng mi cng vic khc, ngay c chng trnh x l ngt, thc hin lnh ny mt cch trc tip vi cng vo/ra. Nu s dng cc ch ngt, chng trnh con tng ng vi tng tn hiu ngt c son tho v ci t nh mt b phn ca chng trnh. Chng trnh x l ngt ch c thc hin trong vng qut khi xut hin tn hiu ngt v c th xy ra bt c im no trong vng qut. 2.3 CU TRC B NH: 2.3.1 Phn chia b nh: B nh ca S7-200 c chia thnh 4 vng vi 1 t c nhim v duy tr d liu trong mt khong thi gian nht nh khi mt ngun. B nh S7-200 c tnh nng ng cao,


TRANG - 19

c, ghi c trong ton vng, loi tr cc bit nh c bit SM (Special memory) ch c th truy nhp c. Hnh v 2.5 m t b nh trong v ngoi ca PLC, bao gm: - Vng chng trnh: min b nh c s dng lu tr cc lnh chng trnh. - Vng tham s: min lu tr cc tham s nh: t kha, a ch trm, cng ging

nh vng chng trnh. - Vng d liu: c s dng ct cc d liu ca chng trnh bao gm cc kt

qu cc php tnh, b m truyn thng - Vng i tng: Timer, B m, b m tc cao v cc cng vo/ra tng t

c t trong vng nh cui cng. - Hai vng nh: d liu v vng nh i tng c ngha quan trng trong vic thc

hin mt chng trnh.

Hnh 2.5: B nh trong v ngoi ca S7-200 2.3.2 Vng d liu: Vng d liu l mt min nh ng. N c th c truy cp theo tng bit, tng byte, tng t n (word), hoc theo tng t kp v c s dng lm min lu tr d liu cho cc thut ton, cc hm truyn thng, lp bng, cc hm dch chuyn, xoay vng thanh ghi, con tr a ch, Ghi cc d liu kiu bng b hn ch rt nhiu v cc d liu kiu bng thng ch c s dng theo nhng mc ch nht nh. Vng d liu li c chia thnh nhng min nh nh vi cc cng dng khc nhau. Chng c k hiu bng cc ch ci u ca tn ting Anh, c trng cho cng dng ring ca chng nh sau: - V: Variable memory - I: Input image register - O: Output image register - M: Internal memory bits - SM: Special memory bits 2.3.3 Vng i tng: Vng i tng c s dng lu gi d liu cho cc i tng lp trnh nh cc gi tr tc thi, gi tr t trc ca b m, hay Timer. D liu kiu i tng bao gm cc thanh ghi ca Timer, cc b m tc cao, b m vo/ra tng t v cc thanh ghi Accumulator(AC).

Chng trnh

Tham s

D liu

Vng i tng

Chng trnh

Tham s

D liu

Chng trnh

Tham s

D liu

EEPROM Min nh ngoi


TRANG - 20

Kiu d liu i tng b hn ch rt nhiu v cc d liu kiu i tng ch c ghi theo mc ch cn s dng i tng .

Vng nh CPU 221 CPU 222 CPU 224 CPU 226

V V0.0V2047.7 V0.0V2047.7 V0.0V5119.7 V0.0V5119.7 I I0.0I15.7 I0.0I15.7 I0.0I15.7 I0.0I15.7 Q Q0.0Q15.7 Q0.015.7 Q0.0Q15.7 Q0.0Q15.7 M M0.0M31.7 M0.0M31.7 M0.0M31.7 M0.0M31.7 SM SM0.0SM179.7 SM0.0SM179.7 SM0.0SM179.7 SM0.0SM179.7S S0.0S31.7 S0.0S31.7 S0.0S31.7 S0.0S31.7

Vng

d liu

L L0.0L63.7 L0.0L63.7 L0.063.7 L0.0L63.7 Timer T0T255 T0T255 T0T255 T0T255 Counter C0C255 C0C255 C0C255 C0C255 Analog inputs none AIW0AIW30 AIW0AIW62 AIW0AIW62 Analog outputs none AQW0AQW30 AQW0AQW62 AQW0AQW62Thanh nghi ACC AC0AC3 AC0AC3 AC0AC3 AC0AC3

Vng

i

tng

B m tc cao HC0,HC3,HC4,HC5 HC0,HC3,HC4,HC5 HC0HC5 HC0HC5 Bng 4.2: Phn chia vng nh v ton hng PLC S7-200

2.3.4 Phng thc truy cp b nh: - Truy cp theo bit: tn min(+) a ch byte (+) (+) ch s bit. - Truy cp theo byte: tn min (+) B (+) a ch ca byte trong min. - Truy cp theo t: tn min (+) W (+) a ch byte cao ca t trong min. - Truy cp theo t kp: tn min (+) D (+) a ch byte cao ca t trong min. Tt c cc byte thuc vng d liu u c th truy cp c bng con tr. Con tr c nh ngha trong min V hoc cc thanh ghi AC1, AC2 v AC3. Mi con tr ch a ch gm 4 byte (t kp). Quy c s dng con tr truy cp nh sau: & a ch byte (cao) l ton hng ly a ch ca byte, t hoc t kp. *con tr l ton hng ly ni dung ca byte, t hoc t kp con tr ang ch vo.


TRANG - 21

Bng 4.3: Ton hng cho php ca PLC S7-200 2.4 Phng php lp trnh PLC S7-200: PLC S7-200 biu din mt mch logic cng bng mt dy cc lnh lp trnh. Chng trnh bao gm mt dy cc tp lnh. PLC S7-200 thc hin chng trnh bt u t lnh lp trnh u tin v kt thc lp trnh cui trong mt vng qut (scan).

Access Method CPU 221 CPU 222 CPU 224 CPU 226 Bit access (byte.bit)

V0.0V2047.7 I0.015.7 Q0.015.7 M0.0M31.7 SM0.0SM179.7 S0.0S31.7 T0T255 C0C255 L0.0L63.7

V0.0V2047.7 I0.0I15.7 Q0.0Q15.7 M0.0M31.7 SM0.0SM179.7 S0.0S31.7 T0T255 C0C255 L0.0L63.7



Byte access VB0VB2047 IB0IB15 QB0QB15 MB0MB31 SMB0SMB179 AC0AC3 SB0SB31 LB0LB63 Constant

VB0VB2047 IB0IB15 QB0QB15 MB0MB31 SMB0SMB179 AC0AC3 SB0SB31 LB0LB63 Constant



Word access VW0VW2046 T0T255 C0C255 IW0IW14 QW0QW14 MW0MW30 SMW0SMW178 AC0AC3 LW0LW62 SW0SW30 Constant

VW0VW2046 T0T255 C0C255 IW0IW14 QW0QW14 MW0MW30 SMW0SMW178 AC0AC3 AIW0AIW30 AQW0AQW30 LW0LW62 SW0SW30 Constant



Double word access

VD0VD2044 ID0ID12 QD0QD12 MD0MD28 SMD0SMD176 AC0AC3 HC0,3,4,5 SD0SD28 LD0LD60 Constant

VD0VD2044 ID0ID12 QD0QD12 MD0MD28 SMD0SMD176 AC0AC3 HC0,3,4,5 SD0SD28 LD0LD60 Constant

VD0VD5116 ID0ID12 QD0QD12 MD0MD28 SMD0SMD176 AC0AC3 HC0HC5 SD0SD28 LD0LD60 Constant

VD0VD5116 ID0ID12 QD0QD12 MD0MD28 SMD0SMD176 AC0AC3 HC0HC5 SD0SD28 LD0LD60 Constant


TRANG - 22

Mt vng qut (scan cycle) c bt u bng vic c trng thi ca u vo, v sau thc hin chng trnh. Vng qut kt thc bng vic thay i trng thi u ra. Trc khi bt u mt vng qut tip theo, PLC S7-200 thc thi cc nhim v bn trong v nhim v truyn thng. Chu trnh thc hin chng trnh l chu trnh lp. Cch lp trnh cho PLC S7-200 ni ring v cho cc PLC ni chung da trn hai phng php c bn. Phng php hnh thang (Ladder, vit tt l LAD) v phng php lit k lnh (Statement List, vit tt l STL). Nu c mt chng trnh vit di dng LAD, thit b lp trnh s t ng to ra mt chng trnh theo dng STL tng ng. Tuy nhin khng phi mi chng trnh vit di dng STL u c th chuyn sang c dng LAD. i vi thit b iu khin lp trnh PLC S7 - 200, ta khng th lp trnh trc tip ngay trn n c m phi lp trnh gin tip bng cch s dng mt trong nhng phn mm sau y :

- STEP 7 Micro/DOS - STEP 7 Micro/WIN

Nhng phn mm ny u c th ci t c trn cc my lp trnh h PG7xx hoc cc my tnh c nhn (PC). Cng vic lp trnh l ta s dng my tnh tin hnh lp ghp cc lnh c bn li vi nhau nhm tha mn nhng yu cu ra ca quy trnh cng ngh ri sau mi chuyn vo PLC iu khin. Cc lnh c bn ny thng thng 2 dng LAD (Ladder Logic) v STL (Statement List). 2.4.1 Phng php LAD: LAD l mt ngn ng lp trnh bng ha, nhng thnh phn c bn dng trong LAD tng ng vi cc thnh phn ca bng iu khin bng rle. Trong chng trnh LAD, cc phn t c bn dng biu din lnh logic nh sau: - Tip im: l biu tng (Symbol) m t cc tip im ca r le.

Tip im thng m Tip im thng ng

- Cun dy (coil): ( ) l biu tng m t rle, c mc theo chiu dng

in cung cp cho r le. - Hp (Box): l biu tng m t cc hm khc nhau, n lm vic khi c dng in

chy n hp. Nhng dng hm thng c biu din bng hp l cc b thi gian (Timer), b m (counter) v cc hm ton hc. Cun dy v cc hp phi mc ng chiu dng in.

- Mng LAD: L ng ni cc phn t thnh mt mch hon thin, i t ng ngun bn tri sang ng ngun bn phi. ng ngun bn tri l dy pha, ng ngun bn phi l dy trung tnh v cng l ng tr v ngun cung cp (thng khng c th hin khi dng chng trnh STEP 7 MICRO / DOS hoc STEP 7 MICRO/WIN. Dng in chy t tri qua tip im n ng cc cun dy hoc cc hp tr v bn phi ngun.

2.4.2 Phng php Lit k lnh (STL): Phng php lit k lnh (STL) l phng php th hin chng trnh di dng tp hp cc cu lnh. Mi cu lnh trong chng trnh biu din mt chc nng ca PLC. Phng php lp trnh LAD ph hp cho nhng ngi lp trnh quen suy lun v k thut, cn STL ph hp cho ngi lp trnh quen suy lun v tin hc.


TRANG - 23

Chng 3: TP LNH PLC S7-200 3.1 LNH C BN : 3.1.1 Lnh vo/ra : - LOAD (LD) : Lnh LD np gi tr logic ca mt tip im vo trong bit u tin ca ngn xp, cc gi tr cn li trong ngn xp b y li xung mt bit. Ton hng gm I, Q, M, SM, V, C, T.

o Dng LAD : Tip im thng m s ng nu I0.0 =1

o Dng STL : LD I0.0

= Q0.0

- LOAD NOT (LDN) : Lnh LDN np gi tr logic ca mt tip im vo trong bit u tin ca ngn xp, cc gi tr cn li trong ngn xp b y li xung mt bit. Ton hng gm : I, Q, M, SM, V, C, T.

o Dng LAD : Tip im thng ng s m khi I0.0 =1

o Dng STL : LDN I0.0

= Q0.0

- OUTPUT (=) : Lnh sao chp ni dung ca bit u tin trong ngn xp vo bit c ch nh trong lnh. Ni dung ngn xp khng b thay i. Ton hng bao gm : I,Q,M,SM,T,C (bit)

o M t lnh OUTPUT bng LAD nh sau : Nu I0.0 = 1 th Q0.0 s ln 1 (cun dy ni vi ng ra Q0.0 c in)

o Dng STL : Gi tr logic I0.0 c a vo bit u tin ca ngn xp, v bit ny c sao chp vo bit ng ra Q0.0 . LD I0.0

= Q0.0


TRANG - 24

3.1.2 Cc lnh ghi/xa gi tr cho tip im : - SET (S) : Lnh dng ng cc im gin on c thit k. Trong LAD, logic iu khin dng in ng cc cun dy u ra. Khi dng iu khin n cc cun dy th cc cun dy ng cc tip im. Trong STL, lnh truyn trng thi bit u tin ca ngn xp n cc im thit k. Nu bit ny c gi tr bng 1, cc lnh S s ng 1 tip im hoc mt dy cc tip im (gii hn t 1 n 255). Ni dung ca ngn xp khng b thay i bi cc lnh ny.

o Dng LAD : ng mt mng gm n cc tip im k t a ch S-bit, Ton hng bao gm I, Q, M, SM,T, C,V (bit)

o Dng STL : Ghi gi tr logic vo mt mng gm n bit k t a ch S-

bit LD I0.0

S Q0.0, 5 - RESET (R) : Lnh dng ngt cc im gin on c thit k. Trong LAD, logic iu khin dng in ngt cc cun dy u ra. Khi dng iu khin n cc cun dy th cc cun dy m cc tip im. Trong STL, lnh truyn trng thi bit u tin ca ngn xp n cc im thit k. Nu bit ny c gi tr bng 1, cc lnh R s ngt 1 tip im hoc mt dy cc tip im (gii hn t 1 n 255). Ni dung ca ngn xp khng b thay i bi cc lnh ny.

o Dng LAD : ngt mt mng gm n cc tip im k t S-bit. Nu S-bit li ch vo Timer hoc Counter th lnh s xo bit u ra ca Timer/ Counter ... .Ton hng bao gm I, Q, M, SM,T, C,V (bit)

o Dng STL : xa mt mng gm n bit k t a ch S-bit. Nu S-bit li ch

vo Timer hoc Counter th lnh s xo bit u ra ca Timer/Counter . LD I0.0

R Q0.0, 10

3.1.3 Cc lnh logic i s Boolean : Cc lnh tip im i s Boolean cho php to lp cc mch logic (khng c nh). Trong LAD cc lnh ny c biu din thng qua cu trc mch, mc ni tip hay song song cc tip im thng ng hay cc tip im thng m. Trong STL c th s dng lnh A (AND) v O (OR) cho cc hm h hoc cc lnh AN (AND NOT), ON (OR NOT) cho cc hm kn. Gi tr ca ngn xp thay i ph thuc vo tng lnh.


TRANG - 25

- AND (A) : Dng LAD : Dng STL :

LD I0.0 A I0.1 = Q0.0

- AND NOT(AN) :

Dng LAD : Dng STL : LD I0.0 AN I0.1

= Q0.0

- OR (O): Dng LAD : Dng STL :

LD I0.0 O I0.1

= Q0.0

- OR NOT (ON):

Dng LAD : Dng STL : LD I0.0 ON I0.1 = Q0.0

Ngoi nhng lnh lm vic trc tip vi tip im, S7-200 cn c 5 lnh c bit biu din cc php tnh ca i s Boolean cho cc bit trong ngn xp, c gi l lnh stack logic. l cc lnh ALD (AND Load), OLD (OR Load), LPS (Logic Push), LRD (Logic Read) v LPP (Logic Pop). Lnh stack logic c dng t hp, sao chp hoc xo cc mnh logic. LAD khng c b m dnh cho Stack logic. STL s dng cc lnh stack logic thc hin phng trnh tng th c nhiu biu thc con v c biu din nh sau: - AND LOAD (ALD) :

Dng LAD : Dng STL :

LD I0.0 LD I0.1 O Q0.0 ALD = Q0.0


TRANG - 26

- OR LOAD (OLD) : Dng LAD : Dng STL :

LD I0.0 A I0.1 O Q0.0 = Q0.0

- LOGIC PUSH (LPS), LOGIC READ (LRD) , LOGIC POP (LPP) :

Dng LAD: Dng STL: LD I0.0 LPS LD I0.1 O Q0.0 ALD = Q0.0 LRD LD I0.2 O Q0.1 ALD = Q0.1 LPP A I0.3 = Q0.2

ngha ca cc lnh :

Lnh M t Ton hngALD

(And load) Lnh t hp gi tr ca bit u tin v th hai ca ngn xp bng php tnh logic AND. Kt qu ghi li vo bit u tin. Gi tr cn li ca ngn xp c ko ln mt bit.

Khng c

OLD (Or load)

Lnh t hp gi tr ca bit u tin v th hai ca ngn xp bng php tnh logic OR. Kt qu ghi li vo bit u tin. Gi tr cn li ca ngn xp c ko ln mt bit.

Khng c

LPS (Logic Push)

Lnh Logic Push (LPS) sao chp gi tr ca bit u tin vo bit th hai trong ngn xp. Gi tr cn li b y xung mt bit. Bit cui cng b y ra khi ngn xp.

Khng c

LRD (Logic read)

Lnh sao chp gi tr ca bit th hai vo bit u tin trong ngn xp.Cc gi tr cn li ca ngn xp gi nguyn v tr

Khng c


TRANG - 27

V d : Vit chng trnh iu khin ng c bng PLC.

Lp trnh LAD:

Ghi ch : I0.0 : Nt nhn dng I0.1 : Nt nhn m Q0.0 : Cun dy KT Q0.0 : Tip im duy tr

3.1.4 Cc lnh tip im c bit : - Tip im o, tc ng cnh xung, tc ng cnh ln :

NOT N P

C th dng cc lnh tip im c bit pht hin s chuyn tip trng thi ca xung (sn xung) v o li trng thi ca dng cung cp (gi tr nh ca ngn xp). LAD s dng cc tip im c bit ny tc ng vo dng cung cp. Cc tip im c bit khng c ton hng ring ca chnh chng v th phi t chng pha trc cun dy hoc hp u ra. Tip im chuyn tip dng/m (cc lnh sn trc v sn sau) c nhu cu v b nh bi vy i vi CPU 214 c th s dng nhiu nht l 256 lnh. V d:

Dng LAD : Dng STL :

LD I0.0 EU = Q0.0 LD I0.0 ED = Q0.1 LD I0.0 NOT = Q0.2

Biu thi gian :

I0.0

Q0.0

Q0.1

Q0.2

Q0.1

Q0.2


TRANG - 28

- Tip im trong vng nh c bit : o SM0.1 : Vng qut u tin tip im ny ng, k t vng qut th hai

th m ra v gi nguyn trong sut qu trnh hat ng. o SM0.0 : Ngc li vi SM0.1, vng qut u tin th m nhng t vng

qut th hai tr i th ng. o SM0.4 : Tip im to xung vi nhp xung vi chu k l 1 pht. o SM0.5 : Tip im to xung vi nhp xung vi chu k l 1s

3.1.5 Cc lnh can thip vo thi gian vng qut :

MEND, END, STOP, NOP, WDR Cc lnh ny c dng kt thc chng trnh ang thc hin, v ko di mt khong thi gian ca mt vng qut. Trong LAD v STL chng trnh phi c kt thc bng lnh kt thc khng iu kin MEND. C th s dng lnh kt thc c iu kin END trc lnh kt thc khng iu kin. Lnh STOP kt thc chng trnh, n chuyn iu khin chng trnh n ch STOP. Nu gp lnh STOP trong chng trnh chnh, hoc trong chng trnh con th chng trnh ang thc hin s kt thc ngay lp tc. Lnh rng NOP khng c tc dng g trong vic thc hin chng trnh. Lnh WDR s khi ng li ng h quan st (watchdog timer ), v chng trnh tip tc c thc hin trong vng qut ch quan st, cn thn khi s dng lnh WDR.

3.2 CC LNH M (COUNTER) V LNH THI GIAN ( TIMER): 3.2.1 Cc lnh iu khin thi gian Timer : Timer l b to thi gian tr gia tn hiu vo v tn hiu ra nn trong iu khin vn thng c gi l khu tr. Nu k hiu tn hiu (logic) vo l x(t) v thi gian tr to ra bng Timer l th tn hiu u ra ca Timer s l x(t ) S7-200 c 64 b Timer (vi CPU 212) hoc 128 Timer (vi CPU 214) c chia lm hai loi khc nhau: - Timer to thi gian tr khng c nh (On-Delay Timer), k hiu l TON. - Timer to thi gian tr c nh (Retentive On-Delay Timer), k hiu TONR. Hai kiu Timer ca S7-200 (TON v TONR) phn bit vi nhau phn ng ca n i vi trng thi u vo. C hai Timer kiu TON v TONR cng bt u to thi gian tr tn hiu k t thi im c sn ln tn hiu u vo, tc l khi tn hiu u vo chuyn trng thi logic t 0 ln 1, c gi l thi gian Timer c kch, v khng tnh khong thi gian khi u vo c gi tr logic 0 vo thi gian tr tn hiu t trc. Khi u vo c gi tr logic bng 0, TON t ng reset cn TONR th khng. Timer TON c dng to thi gian tr trong mt khong thi gian (min lin thng), cn vi TONR thi gian tr s c to ra trong nhiu khong thi gian khc nhau. Timer TON v TONR bao gm 3 loi vi ba phn gii khc nhau, phn gii 1ms, 10ms v 100ms. Thi gian tr c to ra chnh l tch ca phn gii ca b Timer c chn v gi tr t trc cho Timer. V d Timer c phn gii 10ms v gi tr t trc 50 th thi gian tr l 500ms.


TRANG - 29

phn gii cc loi Timer ca S7-200, loi CPU 214, c trnh by trong bng bn di.

Lnh phn gii Gi tr cc i CPU 214 1 ms 32,767 s T32 v T96

10 ms 327,67 s T33 T36, T97 T100

TON 100 ms 3276,7 s T37 T63, T101 T127

1 ms 32,767 s T0 v T64 10 ms 327,67 s T1 T4, T65 T68

TONR

100 ms 3276,7 s T5 T31, T69 T95 C php khai bo s dng Timer nh sau :

LAD M t Ton hng TON-Txx - IN - PT

Khai bo Timer s hiu xx kiu TON to thi gian tr tnh t khi u vo IN c kch. Nu nh gi tr m tc thi ln hn hoc bng gi tr t trc PT th T-bit c gi tr logic bng 1. c th reset Timer kiu TON bng lnh R hoc bng gi tr logic 0 ti u vo IN.

Txx (word) CPU214:3263 96127 PT: VW, T, (word) C, IW, QW, MW, SMW, C, IW, hng s

TONR-Txx _ _

Khai bo Timer s hiu xx kiu TONR to thi gian tr tnh t khi u vo IN c kch. Nu nh gi tr m tc thi ln hn hoc bng gi tr t trc PT th T-bit c gi tr logic bng 1. Ch c th reset Timer kiu TON bng lnh R cho T-bit.

Txx (word) CPU214: 031 64 95 PT: VW, T, (word) C,IW,QW, MW, SMW, AC, AIW, hng s

Khi s dng Timer TONR, gi tr m tc thi c lu li v khng b thay i trong khong thi gian khi tn hiu u vo c logic 0. Gi tr ca T-bit khng c nh m hon ton ph thuc vo kt qu so snh gia gi tr m tc thi v gi tr t trc. Khi Reset mt b Timer, T-word v T-bit ca n ng thi c xa v c gi tr bng 0, nh vy gi tr m tc thi c t v 0 v tn hiu u ra cng c trng thi logic bng 0. V d: S dng Timer kiu TON

LD I0.0 TON T32, +100 LD T32 = Q0.0

IN PT

IN PT


TRANG - 30

Gin thi gian :

V d: S dng timer kiu TONR

LD I0.0 TONR T1, +100 LDW= T1, +170 R T1, 1

Gin thigian:


TRANG - 31

3.2.2 Cc lnh m Counter: Counter l b m thc hin chc nng m sn xung, trong S7-200 cc b m c chia lm hai loi : b m tin (CTU) v b m tin/li (CTUD). B m tin CTU m s sn ln ca tn hiu logic u vo, tc l m s ln thay i trng thi logic t 0 ln 1 ca tn hiu. S xung m c ghi vo thanh ghi 2 byte ca b m, gi l thanh ghi C-word. Ni dung ca thanh ghi C-word, gi l gi tr m tc thi ca b m, lun c so snh vi gi tr t trc ca b m, c k hiu l PV. Khi gi tr m tc thi bng hoc ln hn gi tr t trc ny th b m bo ra ngoi bng cch t gi tr logic 1 vo mt bit c bit ca n, gi l C-bit. Trng hp gi tr m tc thi nh hn gi tr t trc th C-bit c gi tr logic l 0. Khc vi cc b Timer, cc b m CTU v CTUD u c chn ni vi tn hiu iu khin xa thc hin vic t li ch khi pht ban u (reset) cho b m, c k hiu bng ch ci R trong LAD, hay c qui nh l trng thi logic ca bit u tin ca ngn xp trong STL. B m c reset khi tn hiu xo ny c mc logic l 1 hoc khi lnh R (reset) c thc hin vi C-bit. Khi b m c reset, c C-word v C-bit u nhn gi tr 0.

B m tin/li CTUD m tin khi gp sn ln ca xung vo cng m tin, k hiu l CU hoc bit th 3 ca ngn xp trong STL, v m li khi gp sn ln ca xung vo cng m li, k hiu l CD trong LAD hoc bit th 2 ca ngn xp trong STL. B m tin CTU c min gi tr m tc thi t 0 n 32.767. B m tin/li CTUD c min gi tr m tc thi t 32.768 n 32.767.

LAD M t Ton hng CTU Cxx

Khai bo b m tin theo sn ln ca CU. Khi gi tr m tc thi C-word Cxx ln hn hoc bng gi tr t trc PV, C-bit (Cxx) c gi tr logic bng 1. B m c reset khi u vo R c gi tr logic bng 1. B m ngng m khi C-word Cxx t c gi tr cc i.

Cxx : (word) CPU 214 : 0 47 80 127 PV(word) : VW, T, C, IW, QW, MW, SMW, AC, AIW, hng s, *VD, *AC

CTD-Cxx

Khai bo b m tin/li, m tin theo sn ln ca CU, m li theo sn ln ca CD. Khi gi tr m tc thi C-word Cxx ln hn hoc bng gi tr t trc PV, C-bit (Cxx) c gi tr logic bng 1. B m ngng m tin khi C-word Cxx t c gi tr cc i 32.767 v ngng m li khi C-word Cxx t c gi tr cc i 32.768. CTUD reset khi u vo R c gi tr logic bng 1.

Cxx (word) CPU 214 : 48 79 PV(word) : VW, T, C, IW, QW, MW, SMW, AC, AIW, hng s, *VD, *AC

CU R PV

CU CD R PV


TRANG - 32

V d: S dng b m CTU :

LD I0.0 LD I0.1 CTU C40, +5

Gin thi gian :

V d: S dng b m CTUD :

//NETWORK COMMENTS // LD I0.0 LD I0.1 LD I0.2 CTUD C48, +5

Gin thi gian :


TRANG - 33

3.3 CC LNH SO SNH : Khi lp trnh, nu cc quyt nh v iu khin c thc hin da trn kt qu ca vic so snh th c th s dng lnh so snh theo Byte, Word hay DWord ca S7-200. LAD s dng lnh so snh so snh cc gi tr ca byte, word hay DWord (gi tr thc hoc nguyn). Nhng lnh so snh thng l: so snh nh hn hoc bng (=). Khi so snh gi tr ca byte th khng cn phi n du ca ton hng, ngc li khi so snh cc t hay t kp vi nhau th phi n du ca ton hng l bit cao nht trong t hoc t kp. V d: 7FFF > 8000 v 7FFFFFFF > 80000000

LAD M t Ton hng

= =N n2B

N n1

= =N n1 N n2

I

= =N n1 N n2

D

= =N n1 N n2

R

Tip im ng khi n1=n2 B = byte I = Integer = Word D = Double Integer R = Real

n1, n2(byte): VB, IB, QB, MB, SMB, AC, Const, *VD, *AC

> =N n2 B

N n1

> =N n2N n1I

> =N n2N n1D

> =N n1 N n2

R

Tip im ng khi n1>= n2 B = byte I = Integer = Word D = Double Integer R = Real

n1, n2 (word): VW, T, C, QW, MW, SMW, AC, AIW, hng s, *VD, *AC

< =N n2N n1B

< =N n2N n1I

< =N n2N n1D

< =N n2N n1R

Tip im ng khi n1


TRANG - 34

Trong STL nhng lnh so snh thc hin php so snh byte, Word hay DWord. Cn c vo kiu so snh (=), kt qu ca php so snh c gi tr bng 0 (nu ng) hoc bng 1 (nu sai) nn n c th c kt hp cng cc lnh LD, A, O. to ra c cc php so snh m S7-200 khng c lnh so snh tng ng (nh so snh khng bng nhau , so snh nh hn ) ta c th kt hp lnh NOT vi cc lnh c (= =, >=,


TRANG - 35

ngha : Lnh thc hin php AND tng bit ca hai Word ng vo IN1 v IN2, kt qu c ghi vo 1 Word ng ra OUT. c bit y a ch Word ng vo IN2 v Word ng ra OUT l ging nhau. Ton hng trong cu lnh thuc mt trong cc vng a ch sau

IN1 : VW, T, C, IW, QW, SMW, AC, const IN2 : VW, T, C, IW, QW, SMW, AC

V d : VW10 1 0 1 0 1 1 1 0 0 1 1 1 1 1 0 1 AND

VW12 1 0 0 0 1 0 1 0 1 1 0 1 1 1 0 1

Kt qu VW12 1 0 0 0 1 0 1 0 0 1 0 1 1 1 0 1

3.4.3 Lnh AND DWord :

Dng LAD : Dng STL:

ANDD VD0, VD4

3.4.4 Lnh OR byte : Dng LAD : Dng STL:

ORB VB0, VB1

ngha : Lnh thc hin php OR tng bit ca hai byte ng vo IN1 v IN2, kt qu c ghi vo 1 byte ng ra OUT. c bit y a ch byte ng vo IN2 v byte ng ra OUT l ging nhau. Ton hng trong cu lnh thuc mt trong cc vng a ch sau

IN1 : VB, T, C, IB, QB, SMB, AC, const IN2 : VB, T, C, IB, QB, SMB, AC


TRANG - 36

V d: VD10 1 0 0 0 1 1 1 0

OR

VD20 0 0 1 1 0 1 1 1

Kt qu VD20 1 0 1 1 1 1 1 1

3.4.5 Lnh OR word :

Dng LAD : Dng STL:

ORW VW0, VW2

3.4.6 Lnh OR double word :

Dng LAD : Dng STL:

ORDW VD0, VD4

3.5 CC LNH DI CHUYN NI DUNG NH : Cc lnh di chuyn thc hin vic di chuyn hoc sao chp s liu t vng ny sang vng khc trong b nh. Trong LAD v STL lnh dch chuyn thc hin vic di chuyn hay sao chp ni dung mt byte, mt t n, hoc mt t kp t vng ny sang vng khc trong b nh. Lnh trao i ni dung ca hai byte trong mt t n thc hin vic chuyn ni dung ca byte thp sang byte cao v ngc li chuyn ni dung ca byte cao sang byte thp ca t . Sau y l chi tit ca tng lnh.


TRANG - 37

- MOV_B : Dng LAD Dng STL

MOVB VB0, VB0

ngha: Lnh sao chp ni dung ca byte a ch ng vo IN sang byte c a ch ng ra OUT. c bit trong lnh ny a ch ca byte ng vo IN v a ch byte a ch ng ra OUT ging nhau v thng nm trong cc vng sau:

IN : VB, IB, QB, MB, SMB, AC, const OUT: VB, IB, QB, MB, SMB, AC,

V d : Dng LAD Dng STL

LD I0.0 MOVB 0, VB0 LD I0.1 MOVB 12, VB0

Gii thch : Nu tip im I0.0 ng th ly gi tr 0 ghi vo byte VB0 (xa VB0) Tip theo ng tip im I0.1 th ly s 12 ghi vo VB0. Kt qu a ch byte VB0 c gi tr bng 12. - MOV_W : Dng LAD Dng STL

MOVW VW0, VW0


TRANG - 38

ngha : Lnh sao chp ni dung ca Word a ch ng vo IN sang Word c a ch ng ra OUT. c bit trong lnh ny a ch ca Word ng vo IN v a ch Word a ch ng ra OUT ging nhau v thng nm trong cc vng sau:

IN: VW, IW, QW, MW, SMW, AC, const OUT: VW, IW, QW, MW, SMW, AC

- MOV_DW : Dng LAD Dng STL

MOVDW VD0, VD0

ngha : Lnh sao chp ni dung ca DWord a ch ng vo IN sang DWord c a ch ng ra OUT. c bit trong lnh ny a ch ca DWord ng vo IN v a ch DWord a ch ng ra OUT ging nhau v thng nm trong cc vng sau:

IN: VD, ID, QD, MDW, SMD, AC, const OUT: VD, ID, QD, MD, SMD, AC

- MOV_R : (dch chuyn s thc) Dng LAD Dng STL

MOVR VD0, VD0

ngha : Lnh sao chp ni dung ca s thc cha trong double word c a ch ng vo IN sang double word c a ch ng vo OUT. c bit trong lnh ny a ch ca double word ng vo IN v double word ng ra OUT ging nhau v thng nm trong cc vng sau:

IN: VD, ID, QD, MD, SMD, AC, const OUT: VD, ID, QD, MD, SMD, AC

Khi d liu ghi vo trong cc a ch ny theo nguyn tc sau : Phn nguyn ghi vo word thp Phn thp phn ghi vo word cao


TRANG - 39

V d :

Gii Thch : Tip im I0.0 ng th xa double word 0 (VD0), tip im I0.1 ng th ghi s thc 30,2 vo double word VD0, kt qu nh sau :

VD0

VW2 (word cao) VW0 (word thp) 20 30

3.6 LNH CHUYN I D LIU : 3.6.1 Lnh chuyn i s nguyn h thp lc phn sang led 7 an :

Dng LAD : Dng STL :

SEG VB0, VB0

ngha : Lnh ny c tc dng chuyn i cc s trong h thp lc phn t 0 n F cha trong 4 Bit thp ca byte c a ch ng vo IN thnh gi tr BIT cha trong 8 bit ca byte c a ch ng ra OUT tng ng vi thanh led 7 an . Trong lnh ny byte c a ch ng vo IN v byte c a ch ng ra OUT c th cng a ch v nm trong nhng vng sau:

IN: VB, IB, QB, MB, SMB,AC, const OUT: VB, IB,AB,MB,SMB,AC


TRANG - 40

V d : Dng LAD: Dng STL:

LD I0.0 MOVW +3, VW0 LD I0.1 SEG VB0, AC0

Gii thch : Khi tip im I0.0 ng th s 7 c ghi vo VW0, sau tip im I0.1 ng th gi tr cha trong 4 bit thp ca byte VB0 chuyn thnh 8 bit cha trong thanh ghi AC0. Ta c th minh ha theo bit nh sau :

VB1 VB0 VW0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1

VB1 VB0 0 0 0 0 0 0 1 1

SEG . g f e d c b a AC0 0 0 1 0 0 1 1 1 1

3.6.2 Lnh chuyn i s m BCD sang s nguyn :

Dng LAD : Dng STL :

BCDI VW0

nghi: Lnh ny thc hin php bin i mt s nh thp phn 16 bit cha trong word c a ch ng vo IN sang s nguyn 16 bit cha trong word c a ch ng ra OUT. c bit y word c a ch ng vo IN v word c a ch ng ra OUT c th cng mt a ch. a ch ny thng nm trong cc vng sau :

IN: VW, T, C, IW, QW, MW, SMW, AC, AIW, const OUT: VW, T, C, IW, QW, MW, SMW, AC.


TRANG - 41

V d : Dng LAD Dng STL

LD I0.0 MOVW +1124, AC0 LD I0.1 BCDI AC0

Gii thch: Khi I0.0 ng , gi tr 1124 theo m BCD l 0001 0001 0010 0100 c ghi vo a ch AC0. Tip im I0.1 ng th gi tr BCD c chuyn sang s nguyn v lu vo AC0. Ta biu din theo bit nh sau :

MOV AC0 M BCD 0 0 0 1 0 0 0 1 0 0 1 0 0 1 0 0

BCD-I AC0

S nguyn 0 0 0 0 0 1 0 0 0 1 1 0 0 1 0 0 AC0= 1024 + 64 + 32 + 4 = 1124

3.6.3 Lnh chuyn i s nguyn sang m BCD:

Dng LAD : Dng STL :

I BCD VW0

nghi : Lnh ny thc hin php bin i mt s nguyn 16 bit cha trong word c a ch ng vo IN sang s nh thp phn 16 bit cha trong word c a ch ng ra OUT. c bit y word c a ch ng vo IN v word c a ch ng ra OUT c th cng mt a ch. a ch ny thng nm trong cc vng sau :

IN : VW, T, C, IW, QW, MW, SMW, AC, AIW, const OUT : VW, T, C, IW, QW, MW, SMW, AC.


TRANG - 42

3.6.4 Lnh chuyn i s nguyn sang s thc : Dng LAD : Dng STL :

DTR VD0, VD0

ngha: Lnh ny thc hin php bin i mt s nguyn 32 bit c a ch ng vo IN thnh s thc 32 bit ri ghi vo Dword c a ch ng ra OUT. Trong tan hng IN v OUT c th cng i ch v thuc mt trong cc vng sau :

IN : VD, ID, QD, MD, SMD, AC, HC, const OUT : VD, ID, QD, MD, SMD, AC

3.6.5 Lnh chuyn i s thc sang s nguyn : Dng LAD : Dng STL :

TRUNC VD0, VD0

ngha : Lnh ny thc hin php bin i mt s thc 32 bit cha trong Dword c a ch ng vo IN thnh s nguyn 32 bit ri ghi vo Dword c a ch ng ra OUT. Trong tan hng IN v OUT c th cng i ch v thuc mt trong cc vng sau :

IN : VD, ID, QD, MD, SMD, AC, HC, const OUT : VD, ID, QD, MD, SMD, AC.


TRANG - 43

3.6.6 Lnh ly gi tr nghch o :

Dng LAD : Dng STL : Gi tr Byte

Gi tr Word

Gi tr Double Word

INVB VB0 INVW VW0 INVD VD0

ngha : Lnh c tc dng o gi tr tng Bit ca tan hng ca DW c a ch ng vo IN ri ghi kt qu vo Dword c a ch ng ra OUT. Lnh ny cn c gi l lnh ly gi tr b ca mt s. V d :

VB10 0 0 0 0 0 1 1 1 INVB

VB10 1 1 1 1 1 0 0 0 3.7 LNH TNG GIM MT N V : 3.7.1 Lnh cng s nguyn 1 vo ni dung byte :

Dng LAD : Dng STL :

INCB VB0


TRANG - 44

ngha : Lnh ny c tc dng cng s nguyn 1 n v vi ni dung ca byte c a ch ng vo IN, kt qu c ghi vo byte c a ch ng ra OUT. Byte IN v byte OUT c th cng a ch v lnh ny c s dng cc bit nh c bit SM1.0, SM1.1, SM1.2 bo trng thi kt qu php tnh theo nguyn tc nh sau :

Kt qu tnh SM1.0 SM1.1 SM1.2 = 0 1 S m 1

> byte 1

V d :

Dng LAD : Dng STL :

MOVB 10, VB0 INCB VB0

Gii thch : Tip im I0.0 ng th s 10 c ghi vo VB0, tip im I0.1 ng th ni dung ca VB0 tng ln 1 n v v kt qu c lu li VB0. Lc ny VB0 = 11. 3.7.2 Lnh cng s nguyn 1 vo ni dung word :

Dng LAD : Dng STL :

INCW VW0


TRANG - 45

ngha : Lnh ny c tc dng cng s nguyn 1 n v vi ni dung ca word c a ch ng vo IN, kt qu c ghi vo word c a ch ng ra OUT , word IN v word OUT c th cng a ch v lnh ny c s dng cc bit nh c bit SM1.0, SM1.1, SM1.2 bo trng thi kt qu php tnh theo nguyn tc nh sau :

Kt qu tnh SM1.0 SM1.1 SM1.2

= 0 1 S m 1

> byte 1

3.7.3 Lnh cng s nguyn 1 vo ni dung double word :

Dng LAD : Dng STL :

INCD VD0

ngha : Lnh ny c tc dng cng s nguyn 1 n v vi ni dung ca double word c a ch ng vo IN, kt qu c ghi vo doub word c a ch ng ra OUT , double word IN v double word OUT c th cng a ch v lnh ny cng s dng cc bit nh c bit SM1.0, SM1.1, SM1.2 bo trng thi kt qu php tnh theo nguyn tc nh sau :


= 0 1 S m 1

> byte 1


TRANG - 46

3.7.4 Lnh tr ni dung ca byte i 1 n v :

Dng LAD : Dng STL :

DECB VB0

ngha : Lnh ny c tc dng ly ni dung ca byte c a ch ng vo IN tr i 1 n v , kt qu c ghi vo byte c a ch ng ra OUT , byte IN v byte OUT c th cng a ch v lnh ny cng s dng cc bit nh c bit SM1.0, SM1.1, SM1.2 bo trng thi kt qu php tnh theo nguyn tc nh sau :


= 0 1 S m 1

> byte 1

3.7.5 Lnh tr ni dung ca word i 1 n v :

Dng LAD : Dng STL :

DECW VW0

ngha : Lnh ny c tc dng ly ni dung ca word c a ch ng vo IN tr i 1 n v , kt qu c ghi vo word c a ch ng ra OUT , trong lnh word IN v word OUT c th cng a ch v lnh ny cng s dng cc bit nh c bit SM1.0, SM1.1, SM1.2 bo trng thi kt qu php tnh theo nguyn tc nh sau :

Kt qu tnh SM1.0 SM1.1 SM1.

2 = 0 1 S m 1

> byte 1


TRANG - 47

3.7.6 Lnh tr ni dung ca double word i 1 n v :

Dng LAD : Dng STL :

DECD VD0

ngha : Lnh ny c tc dng ly ni dung ca double word c a ch ng vo IN tr i 1 n v , kt qu c ghi vo double word c a ch ng ra OUT , trong lnh double word IN v double word OUT c th cng a ch v lnh ny cng s dng cc bit nh c bit SM1.0, SM1.1, SM1.2 bo trng thi kt qu php tnh theo nguyn tc nh sau :

Kt qu tnh SM1.0 SM1.1 SM1.

2 = 0 1 S m 1

> byte 1

3.8 CC LNH S HC: 3.8.1 Lnh cng s nguyn 16 bit :

Dng LAD : Dng STL :

+I VW0, VW2

ngha : Lnh thc hin cng cc s nguyn 16 bit IN1 v IN2 , kt qa l mt s nguyn 16- bit c ghi vo OUT , tc l : IN1 + IN2 = OUT Trong IN2 v OUT c th cng a ch v thuc cc vng nh sau : IN1, IN2 : VW,T ,C, IW, QW, MW, SMW, AC, AIW, const. OUT : VW,T ,C, IW, QW, MW, SMW, AC, AIW


TRANG - 48

3.8.2 Lnh tr s nguyn 16 bit

Dng LAD : Dng STL :

+I VW0, VW2

ngha : Lnh c thc hin php tr cc s nguyn 16 bit IN1v IN2 , kt qa l mt s nguyn 16- bit v c ghi vo OUT , tc l : IN1 IN2 = OUT Tng t lnh cng s nguyn 16 bit lnh ny cng c IN2 v OUT cng a ch v thuc cc vng nh sau : IN1, IN2 : VW,T ,C, IW, QW, MW, SMW, AC, AIW, const. OUT : VW,T ,C, IW, QW, MW, SMW, AC, AIW. 3.8.3 Cng s nguyn 32 bit

Dng LAD Dng STL :

+D VD0, VD4

ngha : Lnh thc hin php cng cc s nguyn 32 bit IN1 v IN2, kt qa l mt s nguyn 32 bit c ghi vo OUT, tc l IN1 + IN2 = OUT . Trong lnh IN2 v OUT c th cng a ch v thuc cc vng nh sau : IN1, IN2 : VD,T ,C, ID, QD, MD, SMD, AC, HC, const. OUT : VD,T ,C, ID, QD, MD, SMD, AC. 3.8.4 Tr s nguyn 32 bit

Dng LAD : Dng STL :

INVD VD4 INCD VD4 +D VD0, VD4


TRANG - 49

ngha : Lnh thay v thc hn php tr cc s nguyn 32 bit IN1 v IN2 th y thc hin bng cch ly nghch o ca s thc VD4 sau tng ln 1 n v ri thc hin cng vi VD0 kt qa l mt s nguyn 32 bit c ghi vo OUT . Trong IN2 v OUT c th cng a ch v thuc cc vng nh sau : IN1, IN2 : VD,T ,C, ID, QD, MD, SMD, AC, HC, const. OUT : VD,T ,C, ID, QD, MD, SMD, AC. 3.8.5 Cng s thc :

Dng LAD : Dng STL :

+R VD0, VD4

ngha : Lnh thc hin php cng cc s thc 32 bit IN1 v IN2, kt qu l mt s thc 32 bit c ghi vo OUT, tc l : IN1 + IN2 = OUT Trong ton hng IN2 v OUT c th cng a ch, thng nm trong cc vng sau : IN1, IN2 : VD, ID, QD, MD, SMD, AC, HC, const OUT : VD, ID, QD, MD, SMD, AC 3.8.6 Tr s thc :

Dng LAD : Dng STL :

*R -1.000000, VD4 (nhn 1) +R VD0, VD4

ngha : Lnh thay v thc hin php tr cc s thc 32 bit IN1 v IN2 th y thc hin bng cch nhn s thc IN2 vi 1 ri sau ly IN1 cng vi IN2, kt qu l mt s thc 32 bit c ghi vo OUT, tc l: IN1 + (IN2)(-1) = OUT. Trong ton hng IN2 v OUT c th cng a ch, thng nm trong cc vng sau : IN1, IN2 : VD, ID, QD, MD, SMD, AC, HC, const OUT : VD, ID, QD, MD, SMD, AC


TRANG - 50

3.8.7 Nhn s nguyn 16 bit : Dng LAD : Dng STL :

MUL VW0, VD0

ngha : Lnh thc hin php nhn 2 s nguyn 16bit IN1 v IN2. Kt qu 32 bit cha trong t kp OUT (4 byte). 3.8.8 Chia s nguyn 16 bit :

Dng LAD : Dng STL :

MOVW VW0, VW6 DIV VW2, VD4

ngha : Lnh thc hin php chia s nguyn 16 bit IN1 cho s nguyn 16 bit IN2. Kt qu 32 bit cha trong t kp OUT (4 byte) gm thng s ghi trong mng 16 bit t bit 0 n bit 15 (t thp) v phn d cng 16 bit ghi trong mng t bit 16 n bit 31 (t cao). Trong lnh ny c s dng cc bit nh c bit sau bo trng thi.

Kt qu tnh SM1.0 SM1.1 SM1.2 SM1.3 = 0 1 Bo trn 1

S m 1

Mu = 0 1


TRANG - 51

3.8.9 Nhn s thc 32 bit :

Dng LAD : Dng STL :

*R VD0, VD4

ngha : Lnh thc hin php nhn hai s thc 32bit IN1 v IN2 cho ra kt qu 32 bit cha trong t kp OUT (4 byte). 3.8.10 Chia s thc 32 bit :

Dng LAD : Dng STL :

MOVR VD0, VD8 /R VD4, VD8

ngha : Lnh thc hin php chia s thc 32 bit IN1 cho s thc 32 bit IN2. Kt qa 32 bit cha trong t kp OUT (4 byte). Trong lnh ny cng s dng cc bit nh c bit sau bo trng thi:

Kt qu tnh SM1.0 SM1.1 SM1.2 SM1.3 = 0 1 Bo trn 1

S m 1

Mu = 0 1


TRANG - 52

V d:

Dng LAD: Dng STL:

LD I0.0 MOVW +6000, AC0 MOVW +4000, AC1 MOVW +41, VW10 MOVW +200, VW102 MOVW+4000, W202 LD I0.1 +I AC1, AC0 MUL AC1, VD100 DIV VW10, VD200


TRANG - 53

Kt qu cc php tnh trn: Php cng: Php nhn: AC0=10000 VD100=800000 Php chia: VW202 VW200 VD200= 23 97

Phn d Phn nguyn

3.9 LNH NHY V LNH GI CHNG TRNH CON : Thng thng hat ng ca chng trnh l thc hin cc lnh theo th t t trn xung di trong mt vng qut, bn cnh chng trnh cng cho php thay i v chuyn th t thc hin lnh ty theo yu cu ca ngi lp trnh sao cho vic lp trnh n gin, vng qut chng trnh ngn gn v chng trnh x l tt cc chc nng iu khin. lm c iu ta phi s dng ti nhm lnh iu khin chng trnh gm : lnh nhy, lnh gi chng trnh con. Mun nhy n x l on no trong chng trnh th ta phi nh du trc on bng mt k hiu gi l nhn, tn ca chng trnh con hoc tn ca ngt x l. Vic t nhn cho lnh nhy phi nm trong chng trnh. Nhn ca chng trnh con hoc ca chng trnh x l ngt phi khai bo u chng trnh. Chng trnh s khng hiu khi dng lnh nhy JMP chuyn iu khin t chng trnh chnh vo mt nhn bt k trong chng trnh con hoc trong chng trnh x l ngt. Tng t nh vy cng khng th t mt chng trnh con hay chng trnh x l ngt nhy vo bt c mt nhn no nm ngoi cc chng trnh . 3.9.1 Lnh t nhn :

Dng LAD : Dng STL :

LBL 0

ngha : Lnh ny c th t trong chng trnh chnh v cng c th t trong chng trnh con. Ta c th hiu y l mt a ch chng trnh thc hin bt u t khi c lnh nhy n. a ch nhn ny c t tn theo th t t 0, 1, 2, 3..... 3.9.2 Lnh nhy n nhn :

Dng LAD : Dng STL :

JMP 0

ngha : Lnh ny c th t trong chng trnh chnh v cng c th t trong chng trnh con nhng vi iu kin l trong c a ch nhn . Khi chng trnh thc hin gp lnh ny th chng trnh lp tc nhy n a ch nhn .


TRANG - 54

3.9.3 Lnh gn nhn cho chng trnh con :

Dng LAD : Dng STL :

SBR 0

ngha : Lnh ny thng t u chng trnh con v c a ch theo th t t 0, 1, 2, 3, 4.... Khi trong chng trnh chnh gi n a ch ca chng trnh con no th chng trnh con bt u thc hin t y. 3.9.4 Lnh kt thc chng trnh con :

Dng LAD : Dng STL :

RET

ngha : Lnh ny t cui chnh trnh con. Khi gp lnh ny th chng trnh s kt thc chnh trnh con v tr v (Return) thi hnh lnh k sau lnh gi n.

3.9.5 Lnh gi chng trnh con :

Dng LAD : Dng STL : CPU21x CPU22x CPU21x CPU22x

CALL 0

Call sbr 0

ngha : Lnh gi chng trnh con l lnh chuyn iu khin n chng trnh con c gi. Khi kt thc chng trnh con th vic iu khin li c chuyn tr v lnh tip theo trong chng trnh chnh ngay sau lnh gi chng trnh con. T mt chng trnh con c th gi c mt chng trnh con khc trong n, c th gi nh vy nhiu nht l 8 ln i vi S7-200.

3.10 LNH TRUY CP NG H THI GIAN THC : Trong thit b lp trnh S7-200 k t CPU 214 tr i th trong CPU c mt ng h ghi gi tr thi gian thc gm cc thng s v Nm, thng, ngy, gi, pht, giy v ngy trong tun. ng h ny c cp in lin tc bi ngun pin 3V. Khi thc hin lp trnh cho cc h thng t ng iu khin cn cp nht gi tr ng h thi gian thc ny ta phi thng qua 2 lnh sau :


TRANG - 55

3.10.1 Lnh c : Dng LAD : Dng STL :

TODR VB0

ngha : Lnh ny c ni dung ca ng h thi gian thc ri chuyn sang m BCD v lu vo b m 8 byte lin tip nhau theo th t nh sau :

Trong byte u tin c ch nh bi ton hng T trong cu lnh, byte 7 ch s dng 4 bit thp lu gi tr cc ngy trong tun. 3.10.2 Lnh ghi :

Dng LAD : Dng STL :

TODW VB0

ngha : Lnh ny c tc dng ghi ni dung ca b m 8 byte vi byte u tin c ch nh trong ton hng T vo ng h thi gian thc. Trong T thuc 1 trong nhng vng nh sau : VB, IB, QB, MB, SMB. Nu cn iu chnh cc thnng s v nm, thng, ngy, gi, pht, giy, ngy trong tun th iu chnh cc byte nh sau :


TRANG - 56

V d : iu chnh gi tr ngy ta lm nh sau :

Dng LAD Dng STL

LD I0.0 TODR VB100 MOVB VB102, AC0 INCB AC0 MOVB AC0, VB102 TODW VB100


TRANG - 57

Gi tr trc x l : Sau khi x l : VB100 2003 VB101 02 VB102 30 VB103 09

VB104 20 VB105 35 VB106 0

VB107 4

VB100 2003 VB101 02 VB102 31 VB103 09

VB104 20 VB105 35 VB106 0

VB107 4


TRANG - 58

Chng 4: CU TRC CHNG TRNH CA PLC S7-200 Khi vit chng trnh cho S7-200, ty theo yu cu ca quy trnh cng ngh m chng trnh c th thc hin theo nhiu cu trc lp trnh khc nhau. Trong thc t cu trc lp trnh ca mt chng trnh thng c ph bin theo ba dng. 4.1 CU TRC KIU LP TRNH TUN T : Lp trnh tun t l kiu lp trnh bng cch chia nh bi ton ra lm nhiu bc khc nhau, mi bc thc hin mt chc nng ca chng trnh v ch thc hin khi hi cc iu kin ca n. Cc bc trong chng trnh c lin quan mt thit vi nhau c th biu din theo dng khi nh hnh v 4.1.

Tn hieuReset

Tn hieuReset

Tn hieu t bc tren

ieu kienchuyen bc

ieu kienchuyen bc

Tn hieu chuyentrang thai

Tn hieu chuyentrang thai

Tn hieu tac ong bc sau

Tn hieu tac ong

Hnh 4.1: S khi kiu lp trnh tun t

Tn hiu tc ng l tn hiu do con ngi tc ng (chng hn nt nhn khi ng), tn hiu reset l tn hiu chung cho tt c cc bc (nt dng h thng ), tn hiu chuyn trng thi l tn hiu a ra iu khin cc thit b chp hnh khi bc hi iu kin, tn hiu iu kin chuyn bc c th l tn hiu ly t tn hiu chuyn trng thi bc trn qua timer hoc qua mt cng logic no . minh ho cho kiu lp trnh ny ta xt v d bn di:


TRANG - 59

V d 1 : Lp trnh iu khin 1 dy gm 4 n hat ng nh sau :

- Bc 1 : Nhn I0.1 n 1 sng - Bc 2 : Nhn I0.2 n 1 tt v n 2 sng - Bc3 : Nhn I0.3n 2 tt v n 3 sng - Bc 4 : Nhn I0.4 n 3 tt v n 4 sng - Nhn I0.0 th tt bt k n no ang sng.

S khi :

M0.2

I0.0 I0.1

Q0.1 (n 1) Bc 1

M0.1

Q0.2 (n 2) Bc 2

M0.2

M0.4

M0.3

Q0.3 (n 3) Bc 3

M0.3

Q0.4 (n 4) Bc 4

M0.4


TRANG - 60

Lp trnh dng LAD :

Ghi ch : I0.0: Nt dng I0.1: Nt khi ng bc 1 M0.1: Bin trung gian bc 1 I0.2: Nt khi ng bc 2 M0.2: Bin trung gian bc 2 I0.3: Nt khi ng bc 3 M0.3: Bin trung gian bc 3 I0.4: Nt khi ng bc 4 M0.4 : Bin trung gian bc 4 Q0.1: n 1 Q0.2 : n 2 Q0.3 : n 3 Q0.4 : n 4


TRANG - 61

V d 2 : Lp trnh iu khin 1 dy chuyn sn xut gm 4 ng c hot ng nh sau :

- Nhn nt nhn 1 ng c 1 chy, sau 30 giy mi cho vn hnh ng c 2 - Sau 30s nu nhn nt nhn 2 ng c 2 chy ng thi 1 tt - Sau 30s nu nhn nt nhn 3 ng c 3 chy ng thi 2 tt - Sau 30s nu nhn nt nhn 4 ng c 4 chy ng thi 3 tt - Nhn nt nhn 4 bt k ng c no chy cnhg dng

S khi:

I0.4 I0.1

I0.2

I0.3

I0.4

M0.2

M0.3

M0.4

Bc 1

Bc 2

Bc 3

Bc 4

T37

T38

T39

Reset

Reset

Reset

Reset

10s

10s

10s


TRANG - 62

Lp trnh dng LAD :


TRANG - 63

4.2 CU TRC KIU LP TRNH AUTOMAT : Lp trnh Automat cng chia nh bi ton ra lm nhiu bc, mi bc thc hin mt chc nng khc nhau. Cng vic lp trnh cng lm theo trnh t. - Trc ht ta phi v s trng thi ca h thng vi quy nh nh sau :

Cc trng thi l cc im nt trong s tng ng vi cc bit nh trng thi.

Qu trnh chuyn trng thi l cc mi tn tng ng vi cc tn hiu vo automat.

Cc tn hiu ra c ghi ch bn cnh cc trng thi gy ra tn hiu . Qu trnh chuyn trng thi ch ph thuc vo mt ng vo S khi ca cu trc lp trnh Automat :

Reset

Trang thai 1 Trang thai 2

Trangthai 3

Tn hieu vao S1

Tn hieu vao S2Tn hieu ket thucqua trnh lam viec

Hnh 4.2: S khi kiu lp trnh Automat

- M t cc quan h gia cc trng thi : Cc bin trng thi (State) y c k hiu l S0, S1, S2. Trng thi ca n kt hp tn hiu vo ca trng thi trc s quyt nh cho trng thi sau. C th trn s khi l trng thi 1 kt hp vi tn hiu vo S1 s quyt nh cho trng thi 2, trng thi 2 kt hp vi tn hiu vo S2 s quyt nh cho trng thi 3v..v. - Chn cc bit nh cho cc trng thi : Ta tin hnh chn cc bit nh ni ( Mx.x ) cho cc trng thi tng ng. V d: Lp trnh iu khin 1 ng c hot ng nh sau : Nhn nt khi ng ng c chy, nhn nt dng ng c s ngng v n bo nhp nhy trong 5s, sau 5s ng c mi c th khi ng li c. Nu c s c th ng c s ngng ngay. S trng thi cho h thng :

S co

Khi ong

I0.0

I0.1 (Nut nhan dng )Timer 5s

NutDngChay

en bao


TRANG - 64

Quan h gia cc trng thi : - S0 vi S1 : Trng thi S0 =1 v I0.0 =1 th + Set S1 + Reset S0 - S1 vi S2 : Trng thi S1 =1 v I0.1 = 1 th + Set S2 + Reset S1 - S2 vi S0 : Trng thi S2 =1 v tip im Timer ng th + Set S0 + Reset S2

Chn cc bit nh cho cc trng thi : M0.0 cho S0 M0.1 cho S1 M0.2 cho S2

4.3 CU TRC LP TRNH KIU CHNG TRNH CON : Cu trc lp trnh kiu chng trnh con thng c s dng lp trnh cho cc h thng c quy trnh cng ngh phc tp, c nhiu chc nng lm vic khc nhau. Lc chng trnh ca h thng l mt tp hp gm nhiu chng trnh con ghp li, mi chng trnh con thc hin mt chc nng ca h thng. Cc chng trnh con ny hot ng di s kim sot ca mt chng trnh chnh v hot ng nh sau : - Chng trnh chnh c kt thc bng lnh kt thc chng trnh (MEND) - Chng trnh con l mt b phn ca chng trnh. Cc chng trnh con phi

c vit sau lnh kt thc chng trnh chnh, l lnh MEND. - Cc chng trnh x l ngt l mt b phn ca chng trnh. Nu cn s dng

chng trnh x l ngt phi vit sau lnh kt thc chng trnh chnh MEND. Cc chng trnh con c nhm li thnh mt nhm ngay sau chng trnh chnh. Sau n cc chng trnh x l ngt. Bng cch vit nh vy, cu trc chng trnh c r rng v thun tin hn trong vic c chng trnh sau ny. C th t do trn ln cc chng trnh con v chng trnh x l ngt ng sau chng trnh chnh.


TRANG - 65

Hnh 4.3: Cu trc lp trnh kiu chng trnh con ca S7-200

Main Program ....... MEND

Thc hin trong mt vng qut

SBR 0 chng trnh con th nht ....... RET

Thc hin khi c chng trnh chnh gi

SBR n chng trnh con th n+1 ...... RET

INT n chng trnh x l ngt th n+1 ...... RET

INT 0 chng trnh x l ngt th nht ...... RET

Thc hin khi c tn hiu bo ngt


TRANG - 66

Chng 5: PHN MM LP TRNH V M PHNG 5.1 PHN MM STEP 7-Micro/WIN4.0: 5.1.1 Gii thiu: 5.1.2 Hng dn s dng: 5.1.3 Lp trnh iu khin thit b: 5.2 PHN MM M PHNG S7-200: 5.2.1 Gii thiu: 5.2.2 M phng PLC:


TRANG - 67

Chng 6: PLC S7-300 PLC S7-300 ngoi c nhng c im ca S7-200 cn c nng cp thm, tng s lng u vo ra, hm, 5.1 Cu trc, chc nng PLC S7_300 Cc khi chc nng Khi tn hiu (SM:singnal module)

- Khi ng vo digital: 24VDC, 120/230VAC - Khi ng ra digital: 24VDC - Khi ng vo analog: p, dng, in tr, thermocouple

Khi giao tip (IM): Khi IM360/IM365 dng ni nhiu cu hnh. Chng iu khin nhiu thanh ghi ca h thng. Khi gi lp (DM): Khi gi lp DM370 d phng cc khi tn hiu cha c ch nh. Khi chc nng (FM): th hin nhng chc nng c bit sau:

- m - nh v - iu khin hi tip

X l lin lc (CP): - Ni im-im - Mng PROFIBUS - Ethernet cng nghip

5.2 Module CPU Module CPU l loi module c cha b vi x l, h iu hnh, b nh, cc b thi gian, b m, cng truyn thng (RS485) v c th c 1 vi cng vo ra s. Cc cng vo ra s c trn module CPU c gi l cng vo/ra onboard. PLC S7_300 c nhiu loi module CPU khc nhau. Chng c t tn theo b vi x l c trong n nh module CPU312, module CPU314, module CPU315 Nhng module cng s dng 1 loi b vi x l, nhng khc nhau v cng vo/ra onboard cng nh cc khi hm c bit c tch hp sn trong th vin ca h iu hnh phc v vic s dng cc cng vo/ra onboard ny s c phn bit vi nhau trong tn gi bng thm cm ch IFM(Intergrated Function Module). V d nh Module CPU312 IFM, Module CPU314 IFM Ngoi ra cn c cc loi module CPU vi 2 cng truyn thng, trong cng truyn thng th hai c chc nng chnh l phc v vic ni mng phn tn. Cc loi module ny phn bit vi cc loi module khc bng cm t DP (Distributed Port) nh l module CPU315-DP.


TRANG - 68

Trong lun vn s dng loi module 314 IFM s c gii thiu k phn sau. 5.3 Module m rng Cc module m rng c chia thnh 5 loi chnh: 5.3.1- PS (Power supply): Module ngun nui. C 3 loi:2A, 5A, 10A. 5.3.2- SM (Signal module): Module m rng cng tn hiu vo/ra, bao gm: a-DI (Digital input): Module m rng cc cng vo s. S cc cng vo s m rng c th l 8, 16, 32 tu tng loi module. b-DO (Digital output): Module m rng cc cng ra s. . S cc cng ra s m rng c th l 8, 16, 32 tu tng loi module. c-DI/DO (Digital input/ Digital output): Module m rng cc cng vo/ra s.. S cc cng vo/ra s m rng c th l 8 vo/8 ra hoc 16 vo/ 16 ra tu tng loi module. d-AI (Analog input): Module m rng cc cng vo tng t. S cc cng vo tng t c th l 2, 4, 8 tu tng loi module. e-AO (Analog output): Module m rng cc cng ra tng t. S cc cng ra tng t c th l 2, 4 tu tng loi module. f-AI/AO (Analog input/ Analog output): Module m rng cc cng vo/ra tng t. S cc cng vo/ra tng t c th l 4 vo/2 ra hay 4 vo/4 ra tu tng loi module. 5.3.3 IM (Interface module): Module ghp ni, ni cc module m rng li vi nhau thnh 1 khi v c qun l chung bi 1 module CPU. Thng thng cc module m rng c g lin vi nhau trn 1 thanh gi l rack. Trn mi rack c th gn nhiu nht l 8 module m rng (khng k module CPU, module ngun nui. Mt module CPU S7_300 c th lm vic trc tip vi nhiu nht 4 racks v cc racks ny phi c ni vi nhau bng module IM. 5.3.4 FM (Function module): Module c chc nng iu khin ring. V d nh module PID, module iu khin ng c bc 5.3.5 CP (Communication module): Module phc v truyn thng trong mng gia cc PLC vi nhau hoc gia PLC vi my tnh. 5.4 Ngn ng lp trnh PLC S7_300 c 3 ngn ng lp trnh c bn sau: 5.4.1 Ngn ng lit k lnh, k hiu l STL (Statement List). y l dng ngn ng lp trnh thng thng ca my tnh. Mt chng trnh c ghp bi nhiu cu lnh theo 1 thut ton nht nh, mi lnh chim 1 hng v u c cu trc chung l tn lnh+ton hng. V d:


TRANG - 69

5.4.2 Ngn ng hnh thang, k hiu l LAD (Ladder Logic). y l dng ngn ng ho thch hp vi nhng ngi quen thit k mch iu khin logic.

Hnh 5.1: Ngn ng lp trnh hnh thang 5.4.3 Ngn ng hnh khi, k hiu l FBD (Function Block Diagram). y l dng ngn ng ho thch hp vi nhng ngi quen thit k mch iu khin s.

Hnh 5.2: Ngn ng lp trnh hnh khi thun tin trong vic lp trnh, trong lun vn ny Ngi thc hin chn ngn ng LAD lp trnh. 5.5 Gii thiu PLC S7_300 CPU314IFM 5.5.1 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 lnh nh phn, b nh c chia trn cc vng: + Vng cha chng trnh ng dng:

- OB (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 I124.0I124.3 - 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.


TRANG - 70

V d: FC1, FC7, FC30ngoi ra cn c cc 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 (Data Block) 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 trnh CPU 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 chng trnh, 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 trnh ng 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 cng vo ca module tng t s c module c v chuyn t ng theo nhng a ch. Chng trnh ng dng c 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 cng vo ca module tng t s c module c v chuyn t ng theo nhng a ch. Chng trnh ng dng c 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 s dngcho cc bin nhp tc thi v trao i d liu ca bin hnh thc vi nhng khi gi n. Ton b vng nh s b xo sau khi khi thc hin xong. C th truy nhp theo tng bit (L), byte (LB), t (LW), hoc t kp (LD). 5.5.2 Cc ng vo ra + 20 ng vo s c nh a ch t I124.0 n I126.3 trong :


TRANG - 71

Cc ng vo t I124.0 n I124.3 l cc ng vo c bit c th c dng lm b m tc cao (high speed counter) n 10Khz hoc ngt ngoi. + Cc ng ra s t Q124.0 n Q125.7 c mc in p l 24VDC v dng ti a l 0.5A (16 ng ra s) + C 4 ng vo Analog c a ch t PIW128 n PIW134 v 1ng ra tng t c a ch l PQW128 vi tn hiu dng 20mA hoc p 10V c phn gii 11 bit v 1 bit du. Cc ng vo tng t c c im l ch c truy cp bng t (PIW)

Hnh 5.3: Cu to ca PLC S7_300 CPU314IFM 5.5.3 Tp lnh (s dng dng LAD) a. Cc lnh c bn Nhm lnh logic tip im

Lnh GN V d:

Khi ng vo I0.0 ln mc 1 th ng ra Q0.0 ON Lnh AND V d:

Khi I0.0 v I0.1 ng thi ln mc 1 th ng ra Q0.0 ON


TRANG - 72

Lnh OR V d:

Khi 1 trong 2 ng vo I0.0 hoc I0.1 ln mc 1 th ng ra Q0.0 ON Lnh AND NOT V d:

Khi I0.0 ln mc 1 v I0.1 mc 0 th Q0.0 ON Lnh OR NOT V d:

Khi I0.0 mc 1 hay I0.1 mc 0 th Q0.0 ON Lnh GN c iu kin - Lnh gn gi tr 1

V d:

- Lnh gn gi tr 0 V d:

b. Nhm lnh so snh vi s nguyn v s thc


TRANG - 73

- Vi s nguyn So snh bng

V d:

So snh ln hn V d:

So snh ln hn hoc bng V d:

So snh b hn V d:

S nguyn 16 bits S nguyn 32 bits So snh b hn hoc bng


TRANG - 74

V d:

- Vi s thc

So snh bng So snh khc V d:

So snh ln hn So snh ln hn hoc bng V d:

So snh ln hn So snh b hn hoc bng

V d:

c. Cc lnh ton hc

-Vi s nguyn Lnh cng s nguyn

V d:


TRANG - 75

S nguyn 16 bits S nguyn 32 bits

Lnh tr s nguyn V d:


Lnh nhn s nguyn V d:


Lnh chia s nguyn V d:


- Vi s thc


TRANG - 76

Lnh cng s thc Lnh tr s thc V d:

Lnh nhn s thc Lnh chia s thc

V d:

d. Nhm lnh i kiu d liu Cc lnh chuyn: S BCDs nguyn 16 bits BCDs nguyn 32 bits V d:

S nguyn 16 bitsBCD S nguyn32 bitsBCD V d:

S nguyn16 bitss nguyn32bits


TRANG - 77

V d:

S nguyn 32bitss thc

V d:

Lnh lm trn s (s thcs nguyn 32 bits)

V d:

e. B thi gian (Timer) B thi gian l b to thi gian tr t mong mun gia tn hiu logic u vo u(t) v tn hiu logic u ra y(t). S7_300 c 5 loi Timer khc nhau.Thi gian tr t mong mun c khai bo vi Timer bng 1 gi tr 16 bits trong 2 bits cao nht khng s dng, 2bits cao k tip l phn gii ca Timer, 12 bits thp l 1 s nguyn BCD trong khong 0999 c gi l PV (Preset Value). Thi gian tr t chnh l tch:

t= phn gii*PV

Khng s dng Gi tr PV di dng m BCD

9990 PV

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0


TRANG - 78

phn gii

Thi gian c th c khai bo di dng bng kiu S5T V d: S5T#3s Trong lun vn s dng loi Timer SD l loi Timer tr theo sn ln khng c nh (On Delay Timer):Ng ra ln mc 1 khi ng vo EN=1 v gi tr CV (Current Value)=0.

V d:

Khi ng vo I0.0 ln mc 1 th sau 2s T1 s ON f. B m (Counter) Counter l b m c chc nng m sn xung ca tn hiu u vo. C ti a 256 Counter c k hiu t C0C255 V d: Loi Counter m ln v m xung

- CU : tn hiu m ln (BOOL) - CD : tn hiu m (BOOL)

0 0 10ms

0 1 100ms

1 0 1s

1 1 10s


TRANG - 79

- S : tn hiu t (BOOL), khi c sn ln th gi tr t c np cho CV

- PV : gi tr t (WORD) - R : tn hiu xo (BOOL), khi c sn ln th gi tr CV c

xo v 0. - Q : ng ra - CV : gi tr hin ti ca b m dng Integer - CV_BCD : gi tr hin ti ca b m dng BCD

Loi Counter m ln

Ging loi Counter trn nhng khng c chn kch m xung. 5.5.4 Th vin hm S7 300 thng dng (ph lc B) 5.6 Gii php mng Mng cng nghip l h thng o lng v iu khin hin i bao gm my tnh, PLC, vi x l ghp ni vi cm bin v chp hnh, thng thng cc thit b ny khng tp trung m phn tn, vic trao i thng tin c thc hin di dng s v truyn ni tip. Mng cng nghip thng gm 7 lp: Lp vt l, lp lin kt d liu, lp mng, lp vn chuyn, lp phin, lp trnh v lp ng dng. Tuy nhin c 1 s mng ngi ta ch thit k trn hai hoc ba lp c bn, tu vo mi hng m c cc mng khc nhau. Sau y l 1 s mng cng nghip c s dng rng ri: - Mng Ethernet - Foundation FieldBus, MPI, Profibus - Can - DiviceNet - ModBus - SDS (Smart distributed System) - InterBus-S - AS-Interface (Actuaator Sensor Interface) - Combobus-S, Combobus-D


TRANG - 80

Hin nay, giao tip gia PLC vi my tnh, n gin nht l s dng phn mm WinCC c ci t trn my tnh cng vi cp chuyn i PPI hoc MPI (Nu mun kt ni nhiu PLC) chuyn i tn hiu RS485 sang RS232 truyn sang my tnh vo cng Com RS232. WinCC l phn mm tng i mnh bao gm cc th vin c vit sn tuy nhin WinCC cha phi l 1 ngn ng lp trnh hng i t

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