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BO GIAO DUC VA AO TAOTRNG AI HOC S PHAM KY THUAT TP.HCM

KHOA C KH CHE TAO MAY BO MON C IEN T

GIAO TRNH PLC S7-300LY THUYET VA NG DUNG(DANH CHO SINH VIEN NGANH C IEN T T ONG HOA )

BIEN SOAN:ThS. NGUYEN XUAN QUANG

TP.HCM, THANG 12 NAM 2006

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MUC LUC

Chng 1 Trang 1

1.1Gii thieu PLCS7-300 11.1.1 Thiet b ieu khien kha trnh 11.1.2 Cac module cua PLCS7-300 21.2To chc bo nh CPU 81.3Vong quet chng trnh PLC 101.4Cau truc chng trnh. 111.4.1 Lap trnh tuyen tnh 121.4.2 Lap trnh cau truc 121.4.3 Cac khoi OB ac biet 131.5Ngon ng lap trnh 14Chng 2 Ngon ng lap trnh STL 162.1 Cau truc lenh 162.1.1 Toan hang la d lieu 162.1.2 Toan hang la a ch 182.1.3 Thanh ghi trang thai 202.2 Cac lenh c ban 222.2.1 Nhom lenh logic 22

2.2.2 Lenh oc thanh ghi trong ACCU 28

Chng 3 Ngon ng Graph va ng dung 323.1 Tao mot khoi FB di dang ngon ng Graph 32

3.1.1 Tao mot khoi FB Graph 323.1.2 Viet chng trnh theo kieu tuan t 323.2 Viet chng trnh cho ACTION cho cac step 363.3 Viet chng trnh cho TRANSITION 373.4 Lu va ong chng trnh lai 39

3.5 Goi chng trnh t trong khoi FB1 vao khoi OB1 403.6 Download chng trnh xuong CPU va kiem tra tuan t chng trnh 403.6.1 Download chng trnh xuong CPU 403.6.2 kiem tra tuan t chng trnh 41Chng 4 Phan mem Step 7 424.1 S lc ve phan mem Step 7 424.1.1 Cai at step 7 424.1.2 Cac cong viec khi lam viec vi phan mem Step 7 434.1.3 Seat giao dien PG/PC 43

Truong DH SPKT TP. HCM http://www.hcmute.edu.vn

Thu vien DH SPKT TP. HCM - http://www.thuvienspkt.edu.vn

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4.2 cach tao mot chng trnh ng dung vi Step 7 444.2.1 Cac bc soan thao mot Project 44

4.2.2 Thiet lap phan cng cho tram 464.2.3 Soan thao chng trnh cho cac khoi logic 51Chng 5 Bo hieu chnh PID, cac ham x ly tn hieu tng t

va ng dung 545.1 Gii thieu 455.2 Modun mem FB58 555.2.1 Gii thieu 555.2.2 Cac thong so cua FB58 665.3 Ham FC105,FC106 71

5.3.1 Ham FC105 nh t le ngo vao Analog 715.3.2 Ham FC106 khong nh t le ngo ra Analog 725.4 V du ng dung ieu khien mc nc trong bon 735.4.1 Nguyen ly hoat ong 735.4.2 S o khoi cua he thong t ong 755.4.3 Khai bao cac thong so phan cng 76



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TAI LIEU THAM KHAO

1. Nguyen Hong Sn. Ky Thuat Truyen So Lieu- Nha Xuat Ban Lao ong Va XaHoi.

2. Phan Xuan Minh & Nguyen Doan Phc, 1997 : Ly Thuyet ieu Khien M Nha Xuat Ban Khoa Hoc Va Ky Thuat.

3. Nguyen Doan Phc, Phan Xuan Vu, Vu Van Hoa, 2000. T ong Hoa viSIMATIC S7-300 Nha Xuat Ban Khoa Hoc Va Ky Thuat

4. SIMATIC S7-300 ieu Khien He Thong (Systemhandling ), 2000. ai Hoc SPham Ky Thuat. Trung Tam Viet c. Bo Mon ien ien T.

5. Hang Siemens, SIMATICs Manual.6. http://wwww.ad.Siemens.de/



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thong tin vi moi trng xung quanh. Ben canh o nham phuc bai toan ieukhien so, PLC con phai co them mot so khoi chc nang ac biet khac nh bo

em (Counter), bo nh thi (Timer) va nhng khoi ham chuyen dung.u iem cua bo ieu khien lap trnh c so vi ieu khien noi day:

Tnh nang m rong: kha nang m rong x ly bang cach thay oi chngtrnh lap trnh mot cach de dang.

o tin cay cao. Cach ket noi cac thiet b ieu khien n gian. Hnh dang PLC gon nhe. Gia thanh va chi ph lap at thap. Phu hp vi moi trng cong nghiep.

Cac ng dung cua PLC trong san xuat va trong dan dung:

ieu khien cac Robot trong cong nghiep. He thong x ly nc sach. Cong nghe thc pham. Cong nghe chebien dau mo. Cong nghe san xuat vi mach. ieu khien cac may cong cu. ieu khien va giam sat day chuyen san xuat. ieu khien he thong en giao thong. 1.1.2 Cac module cua PLC S7-300.

e tang tnh mem deo trong cac ng dung thc te ma o phan ln cacoi tng ieu khien co so tn hieu au vao, au ra cung nh chung loai tnhieu vao/ra khac nhau ma cac bo ieu khien PLC c thiet ke khong b cnghoa ve cau hnh. Chung c chia nho thanh cac module. So cac module cs dung nhieu hay t tuy thuoc vao tng bai toan, song toi thieu bao gi cung comodule chnh (module CPU, module nguon). Cac module con lai la nhngmodule truyen nhan tn hieu vi cac oi tng ieu khien, chung c goi lacac module m rong. Tat ca cac module eu c ga tren mot thanh Rack.

Module CPU:



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ay la loai module co cha bo vi x ly, he ieu hanh, bo nh, cac bo thigian, bo em, cong truyen thong, va co the co cac cong vao/ra so. Cac cong

vao/ra tch hp tren CPU goi la cong vao ra onboard.Trong ho PLC S7-300, cac module CPU co nhieu loai va c at ten theo

bo vi x ly ben trong nh : CPU 312, CPU 314, CPU 316,. Nhng modulecung mot bo vi x ly nhng khac nhau so cong vao/ra onboard cung nh cackhoi ham ac biet th c phan biet bang cum ch cai IFM (IntergratedFunction Module). V du nh CPU 312IFM, CPU 314IFM,.

Ngoai ra, con co loai module CPU co hai cong truyen thong, trong ocong th hai dung e noi mang phan tan nh mang PROFIBUS (PROcess Field

BUS). Loai nay i kem vi cum t DP (Distributed Port) trong ten goi. V dumodule CPU315-DP.

Module m rong:

Cac module m rong c thanh 5 loai :

1) PS (Power Supply): module nguon la module tao ra nguon co ien ap 24Vdccap nguon cho cac module khac. Co 3 loai: 2A, 5A va 10A.

en ch th nguon 24Vdc ON/OFF Switch 24Vdc

omino noi day ngo ra ien ap 24Vdc

Cau ch bao ve qua dong

omino noi day vi ien ap 220Vac

Hnh1.2. S o khoi va s o au day cua module nguonPS307;2A (6ES7307-1BA00-0AB)

1

2

3

4

1 5



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2) SM (Signal Module): Module m rong vao/ra, bao gom :a) DI (Digital Input): module m rong cong vao so. So cac cong vao so m

rong co the la 8, 16 hoac 32 tuy thuoc vao tng loai module.

So th t cac ngo vao so trong module

en ch th mc logicBus ben trong cua module

b) DO (Digital Output): module m rong cong ra so. So cac cong vao so mrong co the la 8, 16 hoac 32 tuy thuoc vao tng loai module.

2

3

1

Hnh 1.3. S o au day cua moduleSM221; DI 32 x DC 24V(6ES7321-1BL00-0AA0)

Hnh 1.4. S o au day cua moduleSM221; DI 32 x AC 120V(6ES7321-1EL00-0AA0)

Hnh 1.6. S o au day cua moduleSM 322; DO 16 x AC 120/230 V/1 A;

(6ES7322-1FH00-0AA0)

Hnh 1.5.S o au day cua moduleSM 322; DO 32 x 24 VDC/ 0.5 A;

(6ES7322-1BL00-0AA0)



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So th t cac ngo vao so trong module

en ch th mc logic

Bus ben trong cua module

c) DI/DO (Digital Input/Digital Output): module m rong cong vao/ra so.So cac cong vao/ra so m rong co the la 8 vao/8 ra hoac 16 vao/16 ratuy thuoc vao tng loai module.

So th t cac ngo vao so trongmodule

en ch th mc logic

Bus ben trong cua module

Hnh 1.7. S o au day cua moduleSM 322; DO 16 x Rel. AC 120/230 V;

(6ES7322-1HH01-0AA0)

Hnh 1.8. S o au day cua moduleSM 322; DO 8 x Rel. AC 230V/5A;

(6ES7322-5HF00-0AB0)

2

3

1

Hnh 1.9. S o au day cua moduleSM 323; DI 16/DO 16 x DC 24 V/0.5 A;

(6ES7323-1BL00-0AA0)

2

3

1



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d) AI (Analog Input): module m rong cong vao tng t. Ban chat chungla nhng bo chuyen oi tng t sang so (ADC). So cac cong vao tng

t co the la 2, 4 hoac 8 tuy tng loai module, so bit co the la8,10,12,14,16 tuy theo tng loai module.

V du: Module SM 331; AI 2 x 12 bit; (6ES7331-7KB02-0AB0)Cac dang tn hieu oc c

- ien ap- Dong ien- ien tr- Nhiet o

o phan giai 12 bit

Hnh 1.10. S o au day cua moduleKhi tn hieu vao la ien ap

Hnh 1.11. S o au day cua moduleKhi tn hieu vao la ong ien

Hnh 1.12. S o au day cua moduleKhi tn hieu vao la ien tr

Hnh 1.13. S o au day cua moduleKhi tn hieu vao la Thermocouple



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e) AO (Analog Output): module m rong cong ra tng t. Chung la nhngbo chuyen oi t so sang tng t (DAC). So cong ra tng t co the la 2

hoac 4 tuy tng loai module.

f) AI/AO (Analog Input/Analog Output): module m rong vao/ra tng t.So cac cong vao ra tng t co the la 4 vao/2 ra hoac 4 vao/4 ra tuy tngloai module.

3) IM (Interface Module): Module ket noi.

Hnh 1.14. S o au day cua moduleSM 332; AO 4 x 12 Bit;

(6ES7332-5HD01-0AB0)

Hnh 1.15. S o au day cua moduleIM 365; (6ES7365-0BA01-0AA0)



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ay la loai module dung e ket noi tng nhom cac module m rong thanh motkhoi va c quan ly bi mot module CPU. Thong thung cac module m rong

c ga lien nhau tren mot thanh rack. Moi thanh rack ch co the ga c nhieunhat 8 module m rong (khong ke module CPU va module nguon). Mot moduleCPU co the lam viec nhieu nhat vi 4 thanh rack va cac rack nay phai c noivi nhau bang module IM.

4) FM (Function Module): Module co chc nang ieu khien rieng nh: moduleieu khien ong c bc, module ieu kien ong c servo, module PID,

5) CP (Communication Processor): Module truyen trong gia PLC vi PLC haygia PLC vi PC.

1.2 To chc bo nh CPU. Vung nh chc cac thanh ghi: ACCU1, ACCU2, AR1, AR2, Load memory: la vung nh cha chng trnh ng dung (do ngi s

dung viet ) bao gom tat ca cac khoi chng trnh ng dung OB, FC, FB, cackhoi chng trnh trong th vien he thong c s dung (SFC, SFB) va cac khoid lieu DB. Vung nh nay c tao bi mot phan bo nh RAM cua CPU vaEEPROM (neu co EEPROM). Khi thc hien ong tac xoa bo nh (MRES) toanbo cac khoi chng trnh va khoi d lieu nam trong RAM se b xoa. Cung nh

vay, khi chng trnh hay khoi d lieu c o (down load) t thiet b lap trnh(PG, may tnh) vao module CPU, chung se c ghi len phan RAM cua vungnh Load memory.

Work memory: la vung nh cha cac khoi DB ang c m, khoichng trnh (OB, FC, FB, SFC, hoac SFB) ang c CPU thc hien va phanbo nh cap phat cho nhng tham so hnh thc e cac khoi chng trnh nay traooi tham tr vi he ieu hanh va vi cac khoi chng trnh khac (local block).Tai mot thi iem nhat nh vung Work memory ch cha mot khoi chngtrnh. Sau khi khoi chng trnh o c thc hien xong th he ieu hanh se xoa

khoi Work memory va nap vao o khoi chng trnh ke tiep en lt c thchien.

System memory: la vung nh cha cac bo em vao/ra so (Q, I), cac bienc (M), thanh ghi C-Word, PV, T-bit cua timer, thanh ghi C-Word, PV, C-bitcua Couter. Viec truy cap, sa loi d lieu nhng o nh nay c phan chiahoac bi he ieu hanh cua CPU hoac do chng trnh ng dung.

Co the thay rang trong cac vung nh c trnh bay tren khong co vungnh nao c dung lam bo em cho cac cong vao/ra tng t. Noi cach khac



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cac cong vao/ra tng t khong co bo em va nh vay moi lenh truy nhapmodule tng t (oc hoac gi gia tr) eu co tac dung trc tiep ti cac cong

vat ly cua module.Bang1.1. vung a ch va tam a ch

Ten goi Kch thc truy cap Kch thc toi a (tuythuoc vao CPU)

Process input image (I)

Bo em vao so

I

IB

IW

ID

0.0 127.7

0 127

0 126

0 124

Process output image (Q)

Bo em ra so

Q

QB

QW

ID

0.0 127.70 127

0 126

0 124

Bit memory (M)

Vung nh c

M

MB

MW

MD

0.0 255.70 255

0 254

0 252

Timer (T) T0 T255

Counter (C) C0 C255

Data block (DB)

Khoi d lieu share

DBX

DBB

DBW

DBD

0.0 65535.7

0 65535

0 65534

0 65532

Data block (DI) DIX 0.0 65535.7



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Khoi d lieu instance DIB

DIW

DID

0 65535

0 65534

0 65532

Local block (L)

Mien nh a phngcho cac tham so hnhthc

L

LB

LW

LD

0.0 65535.7

0 65535

0 65534

0 65532

Peripheral input (PI) PIB

PIW

PID

0 65535

0 65534

0 65532

Peripheral output (PQ) PQB

PQW

PQD

0 65535

0 65534

0 65532

Tr phan bo nh EEPROM thuoc vung Load memory va mot phan RAM

t nuoi ac biet (non-volatile) dung e lu gi tham so cau hnh tram PLC nha ch tram (MPI address), ten cac module m rong, tat ca cac phan bo nhcon lai che o mac nh khong co kha nang t nh (non-retentive). Khi matnguon nuoi hoac khi thc hien cong viec xoa bo nh (MRES), toan bo noi dungcua phan bo nh non-retentive se b mat.

1.3Vong quet chng trnh cua PLC.

PLC thc hien chng trnh theo chu trnh lap. Moi vong lap c goi lavong quet (scan). Moi vong quet c bat au bang giai oan chuyen d lieu

t cac cong vao so ti vung bo em ao I, tiep theo la giai thc hien chngtrnh. Trong tng vong quet, chng trnh c thc hien t lenh au tien enlenh ket thuc cua khoi OB1 (Block end). Sau giai oan thc hien chng trnhla giai oan chuyen cac noi dung cua bo em ao Q ti cac cong ra so. Vongquet c ket thuc bang giai oan truyen thong noi bo va kiem tra loi.

Thi gian can thiet e PLC thc hien c mot vong quet goi la thi gianvong quet (Scan time). Thi gian vong quet khong co nh, tc la khong phaivong quet nao cung c thc hien lau, co vong quet c thc hien nhanh tuy



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thuoc vao so lenh trong chng trnh c thc hien, vao khoi d lieu ctruyen thong trong vong quet o.

Nh vay gia viec oc d lieu t oi tng e x ly, tnh toan va viec gi tnhieu ieu khien ti oi tng co mot khoang thi gian tre ung bang thi gianvong quet. Noi cach khac, thi gian vong quet quyet nh tnh thi gian thccua chng trnh ieu khien trong PLC. Thi gian vong quet cang ngan, tnhthi gian thc cua chng trnh cang cao.

Neu s dung cac khoi chng trnh ac biet co che o ngat, v du nh khoiOB40, OB80, Chng trnh cua cac khoi o se c thc hien trong vong quetkhi xuat hien tn hieu bao ngat cung chung loai. Cac khoi chng trnh nay cothe c thc hien tai moi iem trong vong quet ch khong b go ep la phai trong giai oan thc hien chng trnh. Chang han neu mot tn hieu bao ngatxuat hien khi PLC ang giai oan truyen thong va kiem tra noi bo, PLC setam dng cong viec truyen thong, kiem tra, e thc hien khoi chng trnhtng ng vi khoi tn hieu bao ngat o. Vi hnh thc x ly tn hieu ngat nhvay, thi gian vong quet se cang ln khi cang co nhieu tn hieu ngat xuat hientrong vong quet. Do o, e nang cao tnh thi gian thc cho chng trnh ieukhien tuyet oi khong nen viet chng trnh x ly ngat qua dai hoac qua lamdung viec s dung che o ngat trong chng trnh ieu khien.

Tai thi iem thc hien lenh vao/ra, thong thng lenh khong lam viectrc tiep vi cong vao/ra ma ch thong qua bo em ao cua cong trong vung nhtham so. Viec truyen thong gia bo em ao vi ngoai vi trong cac giai oan 1va 3 do he ieu hanh CPU quan ly. mot so module CPU, khi gap lenh vao/rangay lap tc, he thong se cho dng moi cong viec khac, ngay ca chng trnhx ly ngat, e thc hien lenh trc tiep vi cong vao/ra.

Hnh 1.16. Vong quet CPU



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1.4. Cau truc chng trnh.

Chng trnh cho S7-300 c lu trong bo nh cua PLC vung danh

rieng cho chng trnh. Ta co the c lap trnh vi hai dang cau truc khacnhau:

1.4.1. Lap trnh tuyen tnh

Toan bo chng trnh ieu khien nam trong mot khoi trong bo nh. Loailap trnh cau truc ch thch hp cho nhng bai toan t ong nho, khong phctap.

Khoi c chon la khoi OB1, la khoi ma PLC luon luon quet va thc hien cac

lenh trong no thng xuyen, t lenh au tien en lenh cuoi cung va quay lailenh au tien:

1.4.2 Lap trnh cau truc

Chng trnh c chia thanh nhng phan nho vi tng nhiem vu riengbiet va cac phan nay nam trong nhng khoi chng trnh khac nhau. Loai laptrnh co cau truc phu hp vi nhng bai toan ieu khien nhieu nhiem vu vaphc tap. Cac khoi c ban :

Khoi OB (Organization Block): khoi to chc va quan ly chng trnh ieukhien. Co nhieu loai khoi OB vi nhng chc nang khac nhau. Chung cphan biet vi nhau bang so nguyen theo sau nhom ky t OB, v du nh OB1,OB35, OB80

Khoi FC (Program Block): khoi chng trnh vi nhng chc nang rieng bietgiong nh mot chng trnh con hay mot ham (chng trnh co co bien hnhthc). Mot chng trnh ng dung co the co nhieu khoi FC va cac khoi FCnay c phan biet vi nhau bang so nguyen theo sau nhom ky t FC,chang han nh FC1, FC2,

Lenh 1

Lenh 2

Lenh n

OB1

Hinh 1.17. Vong quet PLC



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Khoi FB (Function Block): la khoi FC at biet co kha nang trao oi motlng d lieu ln vi cac khoi chng trnh khac. Cac d lieu nay phai c

to chc thanh khoi d lieu rieng c goi la Data Block. Mot chng trnhng dung co the co nhieu khoi FB va cac khoi FB nay c phan biet vinhau bang so nguyen theo sau nhom ky t FB. Chang han nh FB1, FB2,

Khoi DB (Data Block): khoi d lieu can thiet e thc hien chng trnh. Cactham so cua khoi do ngi s dung t at. Mot chng trnh ng dung co theco nhieu khoi DB va cac khoi DB nay c phan biet vi nhau bang songuyen theo sau nhom ky t DB. Chang han nh DB1, DB2,

Chng trnh trong cac khoi c lien ket vi nhau bang cac lenh goi khoi

va chuyen khoi. Cac chng trnh con c phep goi long nhau, tc t motchng trnh con nay goi mot chng trnh con khac va t chng trnh conc goi lai goi mot chng trnh con th 3.

1.4.3 Cac khoi OB ac biet.

1) OB10 (Tinme of Day Interrupt): Chng trnh trong khoi OB10 se c thchien khi gia tr thi gian cua ong ho thi gian thc nam trong mot khoangthi gian a c quy nh. Viec quy nh khoang thi gian hay so lan goi

OB10 c thc hien nh chng trnh he thong SFC28 hay trong bangtham so cua module CPU nh phan mem STEP 7.

2) OB20 (Time Relay Interrupt): Chng trnh trong khoi OB20 se c thchien sau mot khoang thi gian tre at trc ke t khi goi chng trnh hethong SFC32 e at thi gian tre.

3) OB35 (Cyclic Interrupt): Chng trnh trong khoi OB35 se c thc hiencach eu nhau mot khoang thi gian co nh. Mac nh, khoang thi giannay la 100ms, nhng ta co the thay oi nh STEP 7.

OB1

Hnh 1.18. Lap trnh co cau truc

FC7

FB2FC1

. . .

FB9

FC3

FB5

. . .He

ieu

Hanh

.

.

. .

.

. .

.

.



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4) OB40 (Hardware Interrupt): Chng trnh trong khoi OB40 se c thchien khi xuat hien mot tn hieu bao ngat t ngoai vi a vao CPU thong qua

cac cong onboard ac biet, hoac thong qua cac module SM, CP, FM.5) OB80 (Cycle Time Fault): Chng trnh trong khoi OB80 se c thc hien

khi thi gian vong quet (scan time) vt qua khoang thi gian cc ai a quinh hoac khi co mot tn hieu ngat goi mot khoi OB nao o ma khoi OB naycha ket thuc lan goi trc. Thi gian quet mac nh la 150ms.

6) OB81 (Power Supply Fault): Chng trnh trong khoi OB81 se c thchien khi thay co xuat hien loi ve bo nguon nuoi.

7) OB82 (Diagnostic Interrupt): Chng trnh trong khoi OB82 se c thchien co s co t cac module m rong vao/ra. Cac module nay phai la cacmodule co kha nang t kiem tra mnh (diagnostic cabilities).

8) OB87 (Communication Fault): Chng trnh trong khoi OB87 se c thchien co xuat hien loi trong truyen thong.

9) OB100 (Start Up Information): Chng trnh trong khoi OB100 se c thchien mot lan khi CPU chuyen t trang thai STOP sang RUN.

10)OB101 (Cold Start Up Information-ch vi S7-400): Chng trnh trong khoiOB101 se c thc hien mot lan khi cong tat nguon chuyen t trang thai

OFF sang ON.11)OB121 (Synchronous Error): Chng trnh trong khoi OB121 se c thc

hien khi CPU phat hien thay loi logic trong chng trnh oi sai kieu d lieuhay loi truy nhap khoi DB, FC, FB khong co trong bo nh.

12)OB122 (Synchronous Error): Chng trnh trong khoi OB122 se c thchien khi co loi truy nhap module trong chng trnh.

1.5 Ngon ng lap trnh.

PLC S7-300 co ba ngon ng lap trnh c ban sau:

Ngon ng lap trnh liet ke lenh STL (Statement List). ay la dangngon ng lap trnh thong thng cua may tnh. Mot chng trnh choan chnh bi s ghep noi cua nhieu cau lenh theo mot thuat toan nhatnh, moi lenh chiem mot hang va co cau truc chung ten lenh + toanhang.



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Ngon ng lap trnh LAD (Ladder Logic). ay la dang ngon ng ohoa, thch hp vi nhng ngi lap trnh quen vi viec thiet ke mach ieu

khien logic. Ngon ng lap trnh FBD (Function Block Diagram). ay cung la dangngon ng o hoa, thch hp cho nhng ngi quen thiet ke mach ieukhien so.

Ngon ng lap trnh Graph. ay cung la dang ngon ng o hoa, thchhp cho nhng he thong tuan t.

Ngon ng lap trnh SCL. ay cung la dang ngon ng cap cao, thchhp cho nhng ngi biet viet ngon ng cap cao.

Trong PLC co nhieu ngon ng lap trnh nham phuc vu cho cac oi tngs dung khac nhau. Tuy nhien mot chng trnh viet tren ngon ng LAD hayFBD co the chuyen sang dang STL, nhng ngc lai th khong. Va trong STLco nhieu lenh ma LAD hoac FBD khong co. ay cung la the manh cua ngonng STL:

V du:

Ladder Diagram LAD Stamentl list STL Function BlockDiagram FBD

Hnh 1.19. STL la ngon ng manh nhat

STL

LADFBD



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CHNG 2: NGON NG LAP TRNH STL

2.1.Cau truc lenh

Nh a biet, cau truc cua mot lenh STL co dang

Ten lenh + Toan hang

V du:Nhan : L PIW274 // oc noi dung cong vao cua module Analog

ten lenh toan hang

Trong o toan hanhg co the la mot d lieu hoac mot a ch o nh.

2.1.1 Toan hang la d lieu

- D lieu logic TRUE (1) va (0) co o dai 1 bit.V duCALL FC1

In_Bit_1 = TRUE //Gia tr logic 1 c gan cho bien hnh thc In_Bit_1In_Bit_2 = FALSE // Gia tr logic c gan cho bien hnh thc

In_Bit_2Ret_val = MW0 //Gia tr tra ve.

- D lieu so nh phan.V du

L 2#110011 //Nap so nh phan 110011 vao thanh ghi ACCU1- D lieu la so Hexadecimal x co o dai 1 byte (B#16#x), 1 t (W#16#x)hoac 1 t kep (DW#16#x).

V duL B#16#1E //Nap so 1E vao byte thap cua thanh ghi ACCU1L W#16#3A //Nap so 3A2 vao 2 byte thap cua thanh ghi ACCU1L DW#16#D3A2E //Nap so D3A2E vao thanh ghi ACCU1

-D lieu la so nguyen x vi o dai 2 bytes cho bien kieu INT.



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V duL 930

L -1025

- D lieu la so nguyen x vi do dai 4 bytes dang L#x cho bien kieuDINT.

V duL L#930L L#-2047

- D lieu la so thc x cho bien kieu REAL.V duL 1.234567e+13

L 930.0- D lieu thi gian cho bien kieu S5T dang gi _phut_giay_mili giay.V du

L S5T#2h_1m_0s_5ms- D lieu thi gian cho bien kieu TOD dang gi:phut:giay.V du

L TOD#5:45:00

-

DATE: Bieu dien gia tr thi gian tnh theo nam/thang/ngay.V duL DATE#1999 12 8.

- C: Bieu dien gia tr so em at trc cho bo em.V du

L C#20- P: D lieu bieu dien a ch cua mot bit o nh.V du

L P#Q0.0

-

D lieu k t.V duL ABCDL E



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2.1.2 Toan hang la a ch.a ch o nh trong S7_300 gom hai phan: phan ch va phan so. V du:

PIW 304 hoac M 300.4

phan ch phan so phan ch phan so

a. Phan ch ch v tr va kch thc cua o nh.Chung co the la:- M: Ch o nh trong mien cac bien c co kch thc la 1 bit.- MB: Ch o nh trong mien cac bien c co kch thc la 1 byte(8 bits).- MW: Ch o nh trong mien cac bien c co kch thc la 2 bytes (16

bits).- MD: Ch o nh trong mien cac bien c co kch thc la 4 bytes(32

bits).- I: Ch o nho co kch thc 1 bit trong mien bo em cong vao so.- IB: Ch o nh co kch thc la mot byte trong mien bo em cong vao

so.- IW: Ch o nh co kch thc la mot t trong mien bo em cong vao so.- ID: Ch o nh co kch thc la hai t trong mien bo em cong vao so.- Q: Ch o nh co kch thc 1 bit trong mien bo em cong ra so.- QB: Ch o nh co kch thc la mot byte trong mien bo em cong raso.- QW: Ch o nh co kch thc la mot t trong mien bo em cong ra so.- QD: Ch o nh co kch thc la hai t trong mien bo em cong ra so.- PIB: Ch o nh co kch thc 1byte thuoc vung peripheral input.

Thng la a ch cong vao cua cac module tng t (I/O externalinput).

- PIW: Ch o nh co kch thc 1 t (2byte) thuoc vungperipheral input.Thng la a ch cong vao cua cac module tng t (I/O external

input).- PID: Ch o nh co kch thc 2 t (4bytes) thuoc vungperipheral input.

Thng la a ch cong vao cua cac module tng t (I/O externalinput).

- PQB: Ch o nh co kch thc 1 byte thuoc vung peripheral output.Thng la a ch cong ra cua cac module tng t (I/O external input).

- PQW: Ch o nh co kch thc 1 t (2bytes) thuoc vung peripheraloutput. Thng la a ch cong ra/vao cua cac module tng t (I/Oexternal input).



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- PQD: Ch o nh co kch thc 2 t (4bytes) thuoc vung peripheraloutput. Thng la a ch cong ra vao cua cac module tng t (I/O

external input).- DBX: Ch o nh co kch thc 1 bit trong khoi d lieu DB c m

bang lenh OPN DB( open data block)- DBB: Ch o nh co kch thc 1 byte trong khoi d lieu DB c m

bang lenh OPN DB( open data block)- DBW: Ch o nh co kch thc 1 t trong khoi d lieu DB c m

bang lenh OPN DB( open data block)- DBD: Ch o nh co kch thc 2 t trong khoi d lieu DB c m

bang lenh OPN DB( open data block)

- DBx.DBX: Ch trc tiep o nh co kch thc 1 bit trong khoi d lieuDBx, vi x la ch so cua khoi DB.V du:DB5.DBX 1.6

- DBx.DBB: Ch trc tiep o nh co kch thc 1 byte trong khoi d lieuDBx, vi x la ch so cua khoi DB.V du:DB5.DBB 1.

- DBx.DBW: Ch trc tiep o nh co kch thc 1 t trong khoi d lieuDBx, vi x la ch so cua khoi DB.V du:DB5.DBW 1.

- DBx.DBD: Ch trc tiep o nh co kch thc 2 t trong khoi d lieuDBx, vi x la ch so cua khoi DB.V du:DB5.DBD 1.

- DIX: Ch o nh co kch thc 1 bit trong khoi d lieu DB c mbang lenh OPN DI(Open distance data block)

- DIB:Ch o nh co kch thc 1 byte trong khoi d lieu DB c mbang lenh OPN DI(Open distance data block)

- DBW:Ch o nh co kch thc 1 t trong khoi d lieu DB c mbang lenh OPN DI(Open distance data block)

- DBD:Ch o nh co kch thc 2 t trong khoi d lieu DB c m banglenh OPN DI(Open distance data block)

- L: Ch o nh co kch thc 1 bit trong mien d lieu a phng (localblock) cua cac khoi chng trnh OB,FC,FB.

- LB: Ch o nh co kch thc 1 byte trong mien d lieu a phng(local block) cua cac khoi chng trnh OB,FC,FB.- LW: Ch o nh co kch thc 1 t trong mien d lieu a phng (local

block) cua cac khoi chng trnh OB,FC,FB.-LD: Ch o nh co kch thc 2 t trong mien d lieu a phng (local

block) cua cac khoi chng trnh OB,FC,FB.



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b. Phan so ch a ch cua byte hoac cua bit trong mien nh a xac nh.- Neu o nh a c xac nh thong qua phan ch la co kch thc 1 bit

th phan so se gom a ch cua byte va so th t cua bit trong byte oc tach vi nhau bang dau cham. V du:

I 1.3 // Ch bit th 3 trong byte 1 cua mien nh bo em cong vaoso

M 101.5 // Ch bit th 5 trong byte 101 cua mien cac bien c M.Q 4.5 // Ch bit th 5

- Trong trng hp o nh a c xac nh la byte, t hoac t kep thphan so se la a ch byte au tien trong mang byte cua o nh o.

V du

DIB 15 // Ch o nh co kch thc 1 byte (byte 15) trong khoi DB ac m bang lenh OPN DIDBW 18 // Ch o nh co kch thc 1 t gom 2 bytes 18 va 19

trong khoi DB a c m bang lenh OPN DBDB2.DBW 15 // Ch o nh co kch thc 2 bytes 15 va 16

trong khoi d lieu DB2.MD 105 // Ch o nh co kch thc 2 t gom

4 bytes 105, 106, 107, 108 trong mien nh cac bien c M.

2.1.3 Thanh ghi trang thaiKhi thc hien lenh, CPU se ghi nhan lai trang thai cua phep tnh trunggian cung nh cua ket qua vao mot thanh ghi ac biet 16 bits, c goi lathanh ghi trang thai ( Status Word). Mac du thanh ghi trang thai nay co o dai16 bits nhng ch s dung 9 bits vi cau truc nh sau:

8 7 6 5 4 3 2 1 0BR CC1 CC0 OV OS OR STA RLO FC

FC (First check): Khi phai thc hien mot day cac lenh logic lien tiep nhau

gom cac phep tnh,

va nghch ao, bit FC co gia tr bang 1. Noi cachkhac, FC =0 khi day lenh logic tiep iem va c ket thuc.V du:

A I0.2 //FC = 1AN I0.3 //FC = 1= Q4.0 //FC = 0 RLO (Result of logic operation): Ket qua tc thi cua phep tnh logic vac thc hien. V du lenh

A I0.3



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- Neu trc khi thc hien bit FC = 0 th co tac dung chuyen noi dung cuacong vao so I 0.3 vao bit trang thai RLO.

- Neu trc khi thc hien bit FC = 1 th co tac dung thc hien phep tnh gia RLO va gia tr logic cong vao I 0.3. Ket qua cua phep tnh c ghi laivao bit trang thai RLO.

STA (Status bit) : Bit trang thai nay luon co gia tr logic cua tiep iem cch nh trong lenh. V du ca hai lenh:

A I 0.3AN I0.3

eu gan cho bit STA cung mot gia tr la noi dung cua cong vao so I 0.3. OR: Ghi lai gia tr cua phep tnh logic cuoi cung c thc hien e phu

giup cho viec thc hien phep toan sau o. ieu nay la can thiet v trongmot bieu thc ham hai tr, phep tnh bao gi cung phai c thc hientrc cac phep tnh .

OS (Store overflow bit): Ghi lai gia tr bit b tran ra ngoai mang o nh. OV (Overflow bit): Bit bao ket qua phep tnh b tran ra ngoai mang o nh. CC0 va CC1(Condition code): Hai bit bao trang thai cua ket qua phep tnh viso nguyen, so thc, phep dch chuyen hoac phep tnh logic trong ACCU BR(Binary result bit): Bit trang thai cho phep lien ket hai loai ngon ng laptrnh STL. Chang han cho phep ngi s dung co the viet mot khoi chng

trnh FB hoac FC tren ngon ng STL nhng goi va s dung chung trong motchng trnh khac viet tren LAD. e tao ra c moi lien ket o, ta can phaiket thuc chng trnh trong FB, FC bang lenh ghi:

-1 vao BR, neu chng trnh chay khong co loi .-0 vao BR, neu chng trnh chay co loi.

Khi s dung cac khoi ham ac biet cua he thong (SFC hoac SFB), trang thailam viec cua chng trnh cung c thong bao ra ngoai qua bit trang thaiBR nh sau

-1 neu SFC hay SFB thc hien khong co loi.-0 neu co loi khi thc hien SFC hay SFB.Chu y:Mot chng trnh viet tren STL (tuy thuoc vao tng ngi lap trnh) co

the bao gom nhieu Network. Moi mot Network cha mot cong oan cu the. moi au Network, thanh ghi trang thai nhan gia tr 0, ch sau lenh au tiencua Network, cac bit trang thai mi thay oi theo ket qua phep tnh.

Network 1oan chng trnh 1




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2.2 CAC LENH C BAN

2.2.1 Nhom lenh logicBao gom cac lenh sau

A And AN And Not O Or ON Or Not X ExOr XN ExOr Not

a. Lenh gan

Cu phap = Toan hang la a ch I, Q, M, L, D.

Lenh gan gia tr logic cua RLO ti o nh co a ch c ch th trong toanhang. Lenh tac ong vao thanh ghi trang thai (Status word) nh sau (K hieu ch noi dung bit khong b thay oi, x la b thay oi theo lenh):

BR CC1 CC0 OV OS OR STA RLO FC- - - - - 0 x - 1

V du: Thc hien Q4.0 = I0.3Network 1

A I0.3 //oc noi dung cua I0.3 vao RLO= Q4.0 //a ket qua ra cong Q4.0

b. Lenh thc hien phep tnh AND

Cu phap A

Toan hang la d lieu kieu BOOL hoac a ch I, Q, M, L, D, T, C.



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Neu FC = 0 lenh se gan gia tr logic cua toan hang vao RLO. Ngc lai khi FC= 1 no se thc hien phep tnh AND gia RLO vi toan hang va ghi lai ket qua

vao RLO.Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noidung bit khong b thay oi, x la b thay oi theo lenh):

BR CC1 CC0 OV OS OR STA RLO FC- - - - - x x x 1

V du1: Thc hien Q4.0 = I0.3 AND I0.4 (mac noi tiep hai cong tac)Network 1

A I0.3 // oc noi dung cua I0.3 vao RLOA I0.4 //Ket hp AND vi noi dung cong I0.4= Q4.0 //a ket qua ra cong Q4.0V du 2:

c. Lenh thc hien phep tnh AND vi gia tr nghch aoCu phap AN

Toan hang la d lieu kieu BOOL hoac a ch I, Q, M, L, D, T, C.

Neu FC = 0 lenh se gan gia tr logic nghch ao cua toan hang vao RLO.Ngc lai khi FC = 1 no se thc hien phep tnh AND gia RLO vi gia trnghch ao cua toan hang va ghi la i ket qua vao RLO.

Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noidung bit khong b thay oi, x la b thay oi theo lenh):




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V du1: Thc hien Q4.0 = I0.3 AND NOT (I0.4) (mac noi tiep hai cong tac)

Network 1A I0..3 // oc noi dung cua I0.3 vao RLOAN I0.4 //Ket hp AND vi ao noi dung cong I0.4= Q4.0 //a ket qua ra cong Q4.0

V du 2

d. Lenh OR

Cu phap O

Toan hang la d lieu kieu BOOL hoac a ch I, Q, M, L, D, T, C.Neu FC = 0 lenh se gan gia tr logic cua toan hang vao RLO. Ngc lai khi FC= 1 no se thc hien phep tnh OR gia RLO vi toan hang va ghi lai ket quavao RLO.Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noidung bit khong b thay oi, x la b thay oi theo lenh):


V du



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e. Lenh OR NOTCu phap ON

Toan hang la d lieu kieu BOOL hoac a ch I, Q, M, L, D, T, C.Neu FC = 0 lenh se gan gia tr logic cua toan hang vao RLO. Ngc lai khi FC= 1 no se thc hien phep tnh OR gia RLO vi NOT toan hang va ghi lai ketqua vao RLO.Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noidung bit khong b thay oi, x la b thay oi theo lenh):

V du

f. Lenh thc hien phep tnh AND vi mot bieu thcCu phap A(

Neu FC = 0 lenh se gan gia tr logic cua bieu thc trong dau ngoac sau no vaoRLO. Ngc lai khi FC = 1 no se thc hien phep tnh AND gia RLO vi gia trlogic cua bieu trong dau ngoac sau no va ghi lai ket qua vao RLO.Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noidung bit khong b thay oi, x la b thay oi theo lenh):

V du Q0.4 = (( I0.0 OR M10.0) AND (I0.2 OR M10.3)) AND (M10.1)



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g. Lenh thc hien phep tnh AND vi gia tr nghch ao cua mot bieu thcCu phap AN(

Neu FC = 0 lenh se gan gia tr logic cua bieu thc trong dau ngoac sau no vaoRLO. Ngc lai khi FC = 1 no se thc hien phep tnh AND gia RLO vi gia trnghch ao logic cua bieu trong dau ngoac sau no va ghi lai ket qua vao RLO.Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noidung bit khong b thay oi, x la b thay oi theo lenh):

h. Lenh thc hien phep tnh OR vi gia 1tr mot bieu thcCu phap O(

Neu FC = 0 lenh se gan gia tr logic cua bieu thc trong dau ngoac sau no vaoRLO. Ngc lai khi FC = 1 no se thc hien phep tnh OR gia RLO vi gia trlogic cua bieu trong dau ngoac sau no va ghi lai ket qua vao RLO.Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noi

dung bit khong b thay oi, x la b thay oi theo lenh):

i. Lenh thc hien phep tnh OR vi nghch ao gia tr mot bieu thcCu phap ON(

Neu FC = 0 lenh se gan gia tr logic cua bieu thc trong dau ngoac sau no vao

RLO. Ngc lai khi FC = 1 no se thc hien phep tnh OR gia RLO vi gia trnghch ao logic cua bieu trong dau ngoac sau no va ghi lai ket qua vao RLO.Lenh tac ong vao thanh ghi trang thai ( Status word) nh sau (k hieu ch noidung bit khong b thay oi, x la b thay oi theo lenh):



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j. Lenh ghi gia tr logic 1 vao RLO

Cu phap SET

Lenh khong co toan hang va co tac dung ghi 1 vao RLOLenh tac ong vao thanh ghi trang thai (Status word) nh sau:

BR CC1 CC0 OV OS OR STA RLO FC- - - - - - 1 1 0

k. Lenh gan co ieu kien gia tr logic 1 vao o nh

Cu phap S Toan hang la a ch bit I, Q, M, L, D.Neu RLO = 1, lenh se ghi gia tr 1 vao o nh co a ch cho trong toan hang.Lenh tac ong vao thanh ghi trang thai (Status word) nh sau:


l. Lenh gan co ieu kien gia tr logic 0 vao o nh

Cu phap R

Toan hang la a ch bit I, Q, M, L, D.Neu RLO = 1, lenh se ghi gia tr 0 vao o nh co a ch cho trong toan hang.Lenh tac ong vao thanh ghi trang thai (Status word) nh sau:


m. Lenh phat hien sn len

Cu phap FP

Toan hang la a ch bit I, Q, M, L, D va c s dung nh mot bien c e ghinhan lai gia tr cua RLO tai v tr nay trong chng trnh, nhng cua vong quettrc. Tai moi vong lenh se kiem tra: neu bien c (toan hang) co gia tr 0 va



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RLO co gia tr 1 th se ghi 1 vao RLO, cac trng hp khac th ghi 0, ong thichuyen noi dung cua RLO vao lai bien c. Nh vay RLO se co gia tr 1 trong

mot vong quet khi co sn len trong RLO. V du: Lenh phat hien sn len.A I0.0FP M10.0= Q4.5

Se tng ng vioan chng trnh sau

A I0.0AN M10.0= Q4.5

A I0.0= M10.0Lenh tac ong vao thanh ghi trang thai (Status word) nh sau:

BR CC1 CC0 OV OS OR STA RLO FC- - - - - 0 x x 1

n. Lenh phat hien sn xuong

Cu phap FN

Toan hang la a ch bit I, Q, M, L, D va c s dung nh mot bien c eghi nhan lai gia tr cua RLO tai v tr nay trong chng trnh, nhng cuavong quet trc. Tai moi vong lenh se kiem tra: neu bien c (toan hang)co gia tr 1 va RLO co gia tr 0 th se ghi 1 vao RLO, cac trng hp khacth ghi 0, ong thi chuyen noi dung cua RLO vao lai bien c. Nh vayRLO se co gia tr 1 trong mot vong quet khi co sn xuong trongRLO.Lenh tac ong vao thanh ghi trang thai (Status word) nh sau:

BR CC1 CC0 OV OS OR STA RLO FC- - - - - 0 x x 1

2.2.2 Lenh oc, ghi trong ACCU

Cac CPU cua S7_300 thng co hai thanh ghi Accunulator (ACCU) k hieu laACCU1 va ACCU2. Hai thanh ghi ACCU co cung kch thc 32 bits (1 tkep). Moi phep tnh toan tren so thc, so nguyen, cac phep tnh logic vi mang

Gia tr RLO taivong quet hien thi

Gia tr RLO tai vongquet trc c nh

vao M10.0

Hnh 2.1. Hnh mo ta lenh FP



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nhieu bits eu c thc hien tren hai thanh ghi nay. Chung co cau truc nhsau:

31 24 23 16 15 8 7 0ACCU1

ACCU2

T cao T thap

a. Lenh oc vao ACCU

Cu phap L Toan hang la d lieu (so nguyen, thc, nh phan) hoac a ch. Neu la a chth- Byte IB, QB, PIB, MB, LB, DBB, DIB trong khoang 0 65535- T IW, QW, PIW, MW, LW, DBW, DIW trong khoang 0 65534- T kep ID, QD, PID, MD, LD, DBD, DID trong khoang t 0 65534Neu la d lieu th cac dang d lieu hp le cua toan hang cho trong bang sau

Bytecao

Bytethap

Bytecao

Byte thap

Bytecao

Bytethap

Bytecao

Byte thap



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Bang 2.1: Cac dang d lieu hp le cua toan hang

Lenh L co tac dung chuyen d lieu hoac noi dung cua o nh co a ch la toanhang vao thanh ghi ACCU1. Noi dung cu cua ACCU1 c chuyen vaoACCU2. Trong trng hp gia tr chuyen vao co kch thc nho hn t kep thchung se c ghi vao theo th t byte thap cua t thap, byte cao cua t thap,byte thap cua t cao, byte cao cua t cao. Nhng bit con trong trong ACCU1c ghi 0.V du1

L IB0se chuyen noi dung cua IB0 vao ACCU1 nh sau31 24 23 16 15 8 7 0

ACCU1

V du 2L MW20 //se chuyen noi dung cua MW20 gom 2 bytes MB20, MB21vao ACCU1 theo th t

31 24 23 16 15 8 7 0

D lieu V du Giai thch L +5 hi 5 vao t thap cua ACCU1B#(,) L B#(1,8) hi 1 vao byte cao cua t thap va 8 vao

byte thap cua t thap trong ACCUL# L L#5 hi 5 vao ACCU1(so nguye 32 bits)16# L B#16#2E

L W#A2EBL DW#2C1E_A2EB

lieu dang c so 16

2# L 2#11001101 lieu dang c so 2

L ABL ABCD lieu dang k t

C# L C#1000 lieu la gia tr at trc cho bo emS5TIME#

L S5TIME#2S lieu la gia tr at trc cho Timer(PV)

P# L P#M10.2 lieu la a ch o nh(dung cho contro)

D# L D#2000-6-20 D lieu la gia tr vengay/thang/nam(16bits)

T# L T#0H_1M_10S D lieu ve thi gian gi/phut/giay(32bits)

0 0 0 IB 0



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ACCU1

Lenh khong sa oi thanh ghi trang thai (Status word).

V du 3L 100 // ACCU1 =100L 200 // ACCU1 =200, ACCU2=100

b. Lenh chuyen noi dung cua ACCU1 ti o nh.

Cu phap T

Toan hang la ai ch:- Byte IB, QB, PIB, MB, LB, DBB, DIB trong khoang 0 65535- T IW, QW, PIW, MW, LW, DBW, DIW trong khoang 0 65534- T kep ID, QD, PID, MD, LD, DBD, DID trong khoang t 0 - 65534

Lenh chuyen noi dung cua ACCU1 vao o nh co a ch la toan hang. Lenhkhong thay oi noi dung cua ACCU2.Trong trng hp o nh co kch thc nhohn t kep th noi dung cua ACCU1 c chuyen ra theo th t byte thap cua

t thap, byte cao cua t thap, byte thap cua t cao, byte cao cua t cao.V duT QB0se ch chuyen noi dung cua byte thap cua t thap trong ACCU1 vao IB0 valenhT MW20se ch chuyen byte cao cua t thap vao MW20, byte thap cua t thap vaoMW21.

Lenh khong sa oi thanh ghi trang thai (Status word).

0 0 MB20 MB21



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CHNG 3NGON NG GRAPH VA NG DUNG

Khi lap trnh cho PLC s dung khoi FB th chung ta co the s dung ngonng Graph. Ngon ng nay rat thuan li trong nhng he thong ieu khien tuant. Lu y trong khi cai at phan mem Step7 ta phai chon cai at ngon ng nay.

3.1 To mt khi FB di dng ngn ng Graph3.1.1. To mt khi FB GraphBc 1: Double click vo folderBlocks.Bc 2: Chn trn thanh Menu: Insert > S7 Block > Function Block.Bc 3: Mt hp thoi Properties xut hin. Chn ngn ng lp trnh l Graph

Ri chn OK. Nh vy kt qu l mt khi FB1 c to ra trong folder

Blocks

3.1.2. Vit chng trnh theo kieu tun te tien theo doi xet v du ieu khien khi ong SAO/TAMGIAC cua ongc 3 pha nh sau

ng c khng ng b 3 pha r to lng sc phi c vn hnh c 2 chiuquay. khc phc c dng khi ng ln, ng c phi c khi ng vich kt ni sao - tam gic

Hnh 3.1. Chon ngon ng Graph khi lap trnh tren khoi FB



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YU CU

Khi nhn nt S1 th ng c chy v quay cng chiu kim ng h, v ngc s quay theo chiu ngc li nu nhn nt S2. Cng tc t chnh K1 cho chiuquay cng chiu kim ng h v K2 cho chiu ngc li, kch hot cng tc tch sao l K4 v mt timer. Sau mt khong thi gian khi ng gn 5 s, ngc t ng ngt ch chy sao. Cng tc t chnh K1 vn cn c kch hot vngt s kt ni vi ch chy sao cng tc t K4 trc khi chuyn sang kt nivi ch tam gic cng tc t K3. Chiu quay ca ng c ch c thay ikhi ng c c tt trc . ng c ch c th c tt khi nhn nt S0,c lp vi trng thi hot ng . Trng thi ON ca ng c phi c hin thqua n H1 v H2 tu thuc chiu quay ca ng c. Khi ng c qu ti n sc t ng tt qua r le Q1(S5).

Hoat ong Sao/tamgiac cua ong c 3 pha c trnh bay theo lu ogiai thuat sau

START

S1=1

S2=1

C QUAY C NGCHIU KIM NGH (K1) CH

SAO(K4)

C QUAY N G CCHIU KIMNG H

(K2) CH SAO(K3)

S0=1

SAU10S SAU10S


TAMGIC (K3)

N

NN

N

Y

Y

Y

Y

Y


TAMGIC (K3)

Hnh 3.2. Lu ong giai thuat cua khi ong Sao/tamgiac



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Bang c ch vao ra

Ngo vao Ngo raTHIT BNGOI

A CH THIT B NGOI A CH

S0 I0.0 Q1 Q01S1 I0.1 Q2 Q0.2S2 I0.2 Q3 Q0.3S5 I0.5 Q4 Q0.4Trnht lap trnh nh sau

Sau khi bt u lm vic vi S7 Graph bng cch double click vo khi

FB1 th h thng c chn vo mt STEP u tin v mt TRANSITION utin.

C 2 phng php to cu trc Sequencer.Phng php 1: ch Direct: Insert > DirectPhng php 2: ch Drap-and-Drop: Insert > Drap-and-DropSau y ch trnh by cch vit theo phng php 1

Bc 1: Chn transition 1 v nhp chut vo biu tng mt ln

Kt qu to ra mt step 2. Ti step ny ng c thc hin ch quay cngchiu kim ng h, v mch c kt ni dng SAO. Bc 2: Chn step 2 v chn biu tng

iu ny s m ra mt nhnh xen vo cho ch ng c cng quay cngchiu kim ng h nhng mch c kt ni dng TAM GIC. Nhnh ny btu vi transition 3 (T3)

Bc 3: Tip tc vi con chut ang ti v tr T3, nhp chut chn biutng

V s c chn vo step 3 cng vi transition 4

Bc 4: Chn step 1 v chn biu tng



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iu ny s m ra mt nhnh xen vo cho ch ng c ngc chiu kim ng

h. Nhnh ny bt u vi transition 5 (T5) Bc 5: Tng t nh nhnh chnh ng vi ch quay ca ng c l

cng chiu kim ng h.Vn con chut ti transition 5 v nhp chut vo biutng sau mt ln

Kt qu to ra mt step 4 v transition 6. Ti step ny ng c thc hinch quay ngc chiu kim ng h, v mch c kt ni dng SAO.

tip tc thc hin ging nh nhnh chinh ta c mch nh sau:

Bc 6: V by gi ta hon thnh cu trc ca mt Sequencer bng cchu tin ta chn transition 1 (T1) ri nhp chut chn biu tng

v ri chn step1 hoc g vo s 1



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Hnh 3.2. Tao nhanh trong Graph

3.2. Vit chng trnh cc ACTION cho cc step

Cng c 2 phng php viit chng trnh cc action cho cc step v cctransition: Direct v Drap-and-Drop



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Sau y s s dng phng php Drap-and-Drop : Insert > Drap-and-DropBc 1: Chn trn thanh menu Insert > Action

Kt qu l: Trn con chut s xut hin biu tng sau

Bc 2: chn dng action rng bng cch nhp chut vo actionBc 3: Enter vo cc actionMt action bao gm 1 lnh v 1 a ch. Trong ngon ng Graph co 4 lnh hay sdung :S Set ng ra

R Reset ng raD Delay 1 khoang thi gian (xem them S4 hnh 3)C em s kien

S1 CU C20

S1 CR C20

3.3. Vit chng trnh cc TRANSITION

C cc hm logic Cong tc thng m, Cng tc thng ng, Hmso snh c s dng cho cc iu kin-CONDITION trong cc transition. Vitchng trnh cho cc transition nh sau:Bc 1: Chn View >LAD

Chn vo cng tc thng m

Chn vo cng tc thng ng

Chn vo php so snh

Bc 2: Sau khi nhp chn v chn vo ng v tr c th thot ra bt c lc nobng cch nhn phm ESC

Bc 3: Enter a ch vo. Nhp chut vo vng yu cuRi g vo a ch hoc k hiu ca a ch ( V d I0.0 hoc

I0.0_Nut_nhan_dung )Bc 4:

S dung Counter C20 em so hanh ong cua S1Reset Counter C20



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Khi S4 chayc 20 S thM0.1 ao trang

thai



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3.4. Lu v ng chng trnh li

Khi lu chng trnh li, th phan mem t ng c kim tra (compile)Bc 1: Chn trn thanh menu File > SaveKt qu l: mt hp thoi Select Instance DB c m ra vi thng s mc nhl DBx (vi x trung vi x cua khoi FBx v du neu FB1 th DB1)Bc 2: ng vi mc nh ny bng cch nhp chn OKKt qu l: Khi d liu DB-Data block t ng c to ra trong folderBlocksBc 3: ng chng trnh li bng cch chn File > Close

Hnh 3.3.Chng trnh khi ong sao/tamgiac dung ngon ng Graph



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3.5 Gi chng trnh t trong khi FB1 vo khi OB1

Chng trnh iu khin ng c c gi vo trong khi OB1. Chng tac th to khi OB1 vit di dng LAD, FBD, STL, hoc SCL ( y khiOB1 c to ra di dng LAD. Chng trnh ca khi OB1 c biu din nhs sau. Lm trnh t cc bc nh sau:Bc 1: M folder Blocks trong S7 program trong ca s SIMATIC ManagerBc 2: Double- click vo khi OB1Bc 3: Chn ngn ng vit dng LAD bng cch View > LADBc 4: M Overviews ra nu ch c sn bng cch View > OverwiewsRi nhp chn FB, ri double-click vo FB1Bc 5: G tn ca khi d liu DB1 vo pha trn

Bc 6: Lu v ng khi OB1 li bng cch File > Save ri File >Close

3.6. Download chng trnh xung CPU v kim tra tuan t chng trnh

3.6.1. Download chng trnh xung CPU cho php download chng trnh xung CPU, ta phi download tt c cc khi( DB1, FB1, OB1, FC70/71, FC72 v/hoc FC73) xung CPU theo cc bc sau:

Hnh 3.4. Goi khoi FB trong OB1



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Bc 1: M ca s chnh SIMATIC Manager v chn folder Blocks.Bc 2: Chn menu PLC> Download

3.6.2 Kim tra chng trnh

kim tra chng trnh , i hi cn phi kt ni vi vi CPUBc 1: M ca s chnh SIMATIC Manager.Bc 2: M Sequencer bng cch double-click vo khi FB1.Bc 3: Chn menu Debug > Monitor.

Kt qu l: Trng tri chng trnh c hin th ( Step u tin c kch hot).Step no hot ng c hin th mu xanh



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Chng 4

PHAN MEM STEP7

4.1 S lc ve phan mem STEP7.STEP 7 la mot phan mem dung e phuc vu cho viec at cau hnh va lap trnh

cho cac bo ieu khien lap trnh c (PLC_Programmable Logic Controller). ayla bo phan mem do hang Siemens thiet ke, bao gom cac version c ban sau :

STEP 7 Micro/Dos va STEP 7 Micro/Win danh cho cac ng dung chuan, ngian tren SIMATIC S7-200.

STEP 7 Mini danh cho cac ng dung chuan, n gian tren SIMATIC S7-300 vaSIMATIC C7-620.

STEP 7 danh cho cac ng dung tren SIMATIC S7-300/S7-400, SIMATIC M7-300/M7-400 va SIMATIC C7 vi cac chc nang rong hn:

Co kha nang gan cac thong so cho cac module ham va cac bo x ly truyenthong.

Co the hoat ong che o nhieu may tnh. Truyen thong d lieu toan cuc. Truyen d lieu theo s kien s dung cac khoi ham truyen thong

(communication function blocks).

at cau hnh ket noi.4.1.1 Cai at Step7.

Yeu cau phan cng: He ieu hanh : Windows 95, Windows 98 hay Windows NT. Phan cng :

Bo x ly 80486 hay cao hn. RAM: t nhat la32Mbytes. Man hnh, chuot, ban phm co ho tr Win 95/98/NT.

Cai at STEP 7: Cho a STEP 7 vao o a CD-ROM. Chay chng trnh setup tren a, cung giong nh viec cai at cac phan

mem khac. Tuy nhien viec cai at STEP 7 co vai iem khac biet so vi cac

phan mem khac:



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Khai bao so hieu san pham: so hieu san pham luon i kem theo a.Do o khi qua trnh cai at yeu cau so hieu san pham, ban phai ien ay ucac thong tin vao cac muc yeu cau.

ang ky ban quyen (AuthorsW): ban quyen cua STEP 7 do Simenscung cap thng c cha trong a mem rieng (mau o). Ta co the angky ban quyen ngay trong qua trnh cai at hay sau khi cai at phan memxong ban chay chng trnh AuthorsW.exe co trong danh sach cuaSIMATIC.

4.1.2 Cac cong viec khi lam viec vi phan mem STEP 7.

Lap ke hoach cho bo ieu khien. Thiet ke cau truc chng trnh. Khi ong STEP 7. Tao cau truc project. at cau hnh cho tram. at cau hnh mang va cac ket noi truyen thong. nh ngha cac ky hieu. Tao chng trnh. oi vi S7: tao va anh gia cac d lieu tham chieu. at cau hnh cac thong iep. at cau hnh cac bien ieu khien. Download chng trnh xuong bo ieu khien. Kiem tra chng trnh. Quan sat hoat ong va chan oan loi.

4.1.3. Set giao dien PG/PC.

Vi viec thiet lap nay, giup ban thiet lap kieu ket noi giao tiep gia thiet blap trnh (PC) va bo ieu khien logic kha trnh (PLC).

Khi Set PG/PC Interfaces lan au tien, ta phai cai at module giao tiep nhsau:



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Hnh 4.1. Set giao dien PG/PC

Trong hop thoai Set PG/PC Interfaces ta chon loai card phu hp chuangiao tiep he thong mang va click vao nut Properties

Hop thoai Properties - PC Adapter hien ra, ta thiet lap cac thong so giaotiep can thiet nh: a ch, toc o truyen,4.2 CACH TAO 1 CHNG TRNH NG DUNG VI STEP7

4.2.1. Cac bc soan thao 1 Project

Cach xay dng cau hnh phan cng cho tram PLC.

V du xay dng cau hnh phan cng cho 1 tram nh sau:

- Phan cng cua tram gom mot thanh ray

RACK-300 : thanh RAIL- Tren thanh nay co gan cac moun : nguon PS , CPU, DI/DO, AI, AO tren cac

SLOT Trong o :

SLOT 1: co gan moun nguon PS 307 5A vi ma so : 6ES7 307-1EA00-0AA0

Chon loai modulethch hp. Click chon Install.



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SLOT 2 va SLOT 3 : Co gan moun CPU 300 CPU 315-2 DP vi ma so :6ES7 315- 2AFO3-OABO- V1.2 moun nay e truyen d lieu t S7-300

bang ng truyen mang MPI va PROFIBUS vi toc o 1.5 MB SLOT 4 : Moun tn hieu ngo vao/ ra digital DI8 /DO8 x24V/0.5A vi ma

so : 6ES7 323-1BH00-0AA0

SLOT 5 : Moun tn hieu ngo vao analog AI 2x12bit vi ma so : 6ES7 331-7KB02-0AB0

SLOT 6 : Moun tn hieu ngo ra analog A0 2x12bit vi ma so : 6ES7 332-5HB01-0AB0

Chu y: ta khong the at cac thanh phan ca so ben phai vao ca so ben trai

mot cach tuy tien khong theo mot th t. Thng th cac thanh phan c at

vao cac Slot ca so ben trai theo th t nh sau:

Slot 1: ch s dung at modul nguon. Slot 2: ch s dung at modul CPU. Slot 3: thong thng e rong. Slot 4 ti Slot 11: dung cho cac module truyen thong x ly( modul xuat,

modul nhap, modul vao ra tng t).

Hnh 4.2. Th t sap xep cua cac Slot tren mot Rack



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Chon New Project Wizard

4.2.2. Thiet lap phan cng cho tram

1. Khi ong phan mem SIMATIC Manager

Start -> SIMATIC Manager hoac doub_ click vao bieu tng :

Hnh 4.2.Bieu tng cua SIMATIC Manager

2. Tao 1 Project mi : File ->New Project Wizard

Hnh 4.3.Tao 1 Project mi

3. at ten cho Project :

Hnh 4.4.at ten cho Project

Doub_click vao icon

SIMATIC Manager

1.at ten Project2.Chon OK



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4. Chen SIMATIC 300 Station: Insert -> station -> SIMATIC 300 Station

Hnh 4.5.Chen 1 tram SIMATIC mi

5. Chon SIMATIC 300 Station(1)

Hnh 4.6:Chon tram SIMATIC va tao

6. M cau hnh phan cng :

Chon SIMATIC300 Station

Chon SIMATIC 300(1)



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Click doub vao Hardware hoac vao Edit -> Open Object

Hnh 4.7:M cau hnh phan cng

7. Lay thanh rail slot 0 nam di dau + cua RACK :

SIMATIC 300 -> RACK-300 -> doub- click Rail

Hnh 4.8:V tr cua moi Slot8. Click vao SLOT 1

Chon Open Object

Slot 1: moun nguon PS Slot 2: moun CPU 300 Slot 4: moun SM-DI/DO Slot 5: moun SM-AI Slot 6: moun SM-A0

Doub_click

vao Rail



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chon moun nguon PS 307 5A vi ma so : 6ES7 307-1EA00-0AA0, bang

cach doub_click vao PS 307 5A

Hnh 4.9. Khai bao a ch nguon

9. Tng t nh bc 8 click vao Slot 2 chon moun CPU 300 CPU 315-2DP vi ma so : 6ES7 315- 2AFO3-OABO bang cach doub_click vao V1.2

luc o se xuat hien hop thoai Properties nhap a ch DP cua CPU la 15 va

nhan phm NEW sau o chon OK

Hnh 4.10:Khai bao a ch va mang ket noi Profibus

Ket qua se tao ra : he thong chu (1) PROFIBUS(1) : DP

Doub_click vao

PS 307 5A

Nhap a chCPU

Chon New



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Hnh 4.11:Khai bao CPU

10.Click vao slot 4 : t SM-300 chon moun tn hieu ngo vao/ ra digitalDI8 /DO8 x24V/0.5A vi ma so : 6ES7 323-1BH00-0AA0 bang cach doub _click

vao DI8 /DO8 x24V/0.5A

11. Click vao slot 5 t SM-300 chon moun tn hieu ngo vao analog AI 2x12bit

vi ma so : 6ES7 331-7KB02-0AB0 bang cach doub _click vao AI 2x12bit

12. Click vao slot 6 t SM-300 chon moun tn hieu ngo ra analog A0 2x12bit vi

ma so : 6ES7 332-5HB01-0AB0 bang cach doub _click vao A0 2x12bit

13. Sau khi thiet lap phan cng xong ta tien hanh lu va kiem tra bang cach chon

menu Station > Save and Compile

14. Download cau hnh phan cng xuong di CPU cua PLC bang cach chon menu

PLC -> Download



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Hnh 4.12. Save va download cau hnh phan cng

4.2.3 Soan thao chng trnh cho cac khoi logic

Sau khi khai bao xong cau hnh cng cho mot tram PLC va quay tr ve ca

so chnh cua step7 ta se thay Step7 trong th muc SIMATIC 300(1) bay gi co

them cac th muc con CPU315-2DP, S7 Program(1), Sources, Blocks

M ca so SIMATIC manager len va chon Block

M tat ca cac khoi logic (OB, FC, FB, DB) cha chng trnh ng dung se nam

trong th muc Block. Mac nh san trong th muc nay a co san kho OB1

1. Click + Simatic 300(1)2. Click + S7 program(1)3. chon Block



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Hnh 4.13. Chon khoi Blocks

Muon soan thao chng trnh cho khoi OB1 ta doud-click vao bieu tng OB1

ben na ca so ben phai

Hnh 4.14: Lap trnh tren khoi OB1

e khai bao va soan thao chng trnh cho cac khoi OB khac hoac cho cac khoi FC

, FB hay DB, ta co the tao mot khoi mi ngay trc tiep t chng trnh soan thao

bang cach chen them khoi mi o trc t ca so chnh cua step7 bang phm

Double click

vao khoi OB



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Insert -> S7 Block -> chon kieu khoi -> chon so khoi -> nhan OK

Hnh 4.15. Chen them khoi ieu khien

Chon kieu khoi



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CHNG 5

BO HIEU CHNH PID, CAC HAM X LY TN HIEU TNG T VANG DUNG

5.1 Gii thieu.Nhieu nam trc ay bo ieu khien PID c coi la bo ieu khien ly

tng oi vi cac oi tng co mo hnh lien tuc. Bo PID thc s la bo ieukhien ong ma viec thay oi cac tham so cua bo ieu khien co kha nang lamthay oi ac tnh ong va tnh cua he thong ieu khien t ong.

Bo ieu khien PID thc chat la thiet b ieu khien thc hien luat ieu

khien c mo ta bang phng trnh sau:u.(t) = kpe(t) + D

t

I

TdeT

0

1 e.(t)

trong o e(t) la tn hieu vao, u(t) la tn hieu ra cua bo ieu khien, kp la he sokhuech ai cua luat ieu khien ty le , TI hang so thi gian tch phan va TD lahang so thi gian vi phan .

Hnh 5.1. ieu khien vi bo ieu khien PID

Vi bo ieu khien PID, ngi s dung de dang tch hp cac luat ieukhien khac nh luat ieu khien t le (luat P), ieu khien t le - tch phan (luatPI), ieu khien t le -vi phan (luat PD). Bo ieu khien PID luon la mot phant khong the thay the c trong cac qua trnh t ong khong che nhiet o,mc, toc o

Mot trong nhng ng dung cua bo ieu khien PID trong ieu khienthch nghi va ieu khien m la thng xuyen phai chnh nh lai cac tham socua no cho phu hp vi s thay oi khong biet trc cua oi tng cung nhcua moi trng nham am bao c cac ch tieu chat lng a e ra trong hethong. Neu nh ta a t ong hoa c cong viec thay oi tham so nay th boieu khien PID o se la mot bo ieu khien ben vng vi moi tac ong cuanhieu noi cung nh nhieu ngoai len he thong.

Bo hieuchnh PID

oi tngieu

khien

Ngo raNgo vao

-

e(t) u(t)



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Cung chnh v vay ma cac thiet b ieu khien qua trnh nh DCSDisbuted Control system, PLC Programmeble Logic Control,PCS Process

Control System cua cac hang san xuat thiet b t ong tren the gii khongthe thieu c module ieu khien PID hoac cng hoac mem.e s dung tot cac module nay, ngi thiet ke phai nam c cac

phng phap chon luat ieu khien va cac tham so cho bo ieu khien.

Trong phan mem Step 7 co nhieu khoi FB e ho tr viec viet chng trnh ieukhien thiet b s dung luat hieu chnh PID, nh FB40,FB41, FB58, FB59..5.2 Moun mem FB585.2.1 Gii thieu

S o khoi FB58



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Hnh 5.2. S o khoi cua khoi FB58

Hnh 5.3. Cac cau lenh cua FB58iem Setpoint

iem Setpoint at ngo vao SP- INT dang so thc nh mot ai lng vat lhoac t le phan tram. iem setpoint va gia tr x l thng tao thanh sai sophai co cung mot n vS la chon gia tr x l (PVPER_ON)Tuy thuoc vao PVER ON, gia tr co the co c t thiet b ngoai vi hoac dang so thcPVER-ON x l gia tr ngo vao:- TRUE: Gia tr x l c o thong qua thiet b ngoai vi Analog (PIWxxx)

tai ngo

vao PV PER.- FALSE: Gia tri x l co c dang so thc at tai ngo vao PV-IN.S chuyen oi gia tr x l bang ham CRP-IN (PER-MOD)Ham CRP_IN chuyen gia tr ngoai vi sang dang so thc tuy thuoc vao s lachon PER_MODE



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Viec tieu chuan hoa gia tr x l PV_NORM (PF_FAC, PV_OFFS)Ham PV_NORMtnh toan gia tr ngo ra cua ham CRP_IN nh sau:

"Output of PV_NORM" = "Output of CPR_IN" * PV_FAC + PV_OFFSNo c dung vi y nh:PV_FAC:nh he so cua gia tr x l.PV_OFFS:s offset cua gia tr x l.S tieu chuan hoa nhiet o sang t le phan tram: iem setpoint dang %, taphai chuyen gia tr nhiet o c o sang t le %.S tieu chuan hoa t le % sang nhiet o: iem setpoint dang nhiet o taphai chuyen ien ap/dong ien.Viec tnh toan cac thong so:

- PV_FAC = range of PV_NORM/range of CRP_IN;- PV_OFFS = LL(PV_NORM) - PV_FAC * LL(CRP_IN);Vi:

range: dai,vung,mienLL : gii han di

Vi gia tr mac nh (PV_FAC = 1.0 va PV_OFFS = 0.0) th s tieu chuanhoa se khong c thch hp th ket qua gia tr x l la ngo ra tai PV.V du viec tieu chuan hoa gia tr x lNeu at gia tr setpoint la t le % va ban co mien nhiet o la (-20 +85)oC th

ban phai tieu chuan hoa dai nhiet o thanh t le %.S o di ay trnh bay mot v du ve viec chuyen mien nhiet o (-20+85)oC sang t le t 0 100%

Hnh 5.4. V du viec tieu chuan hoa gia tr x l



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Hnh thc sai soS khac biet gia iem setpoint va gia tr x l trc khi b a vao mienchet se tao ra sai so. iem setpoint va gia tr x l phai co cung kieu nv(% hoac ai lng vat l)Mien chet (Deadb_W)Vi moi mot gia tr, Deaband se a ra mot khoang sai soNeu DEADB_W = 0 th Deaband se b giam s kch hoat. Sai so c actrng bang thong so ER

Hnh 5.5. Minh hoa ve mien chet

Thuat toan PID (GAIN, TI, TD, D_F)

S o di ay la s o khoi cua thuat toan PID



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Hnh 5.6. S o khoi cua that toan PID

Thuat toan PID hoat ong nh mot thuat toan ve s nh v. Cac c cau tle,tch phan,vi phan(DIF) c ket noi song song va co the c kch hoathoac khong kch hoat mot cach rieng le. ieu nay cho phep bo P, bo PI, boPID c cau hnh.S ieu chnh cua ngi ieu khien se ho tr bo PI,PID. Bo ieu khiennghch c thi hanh khi s dung mot bo GAIN (cooling controller).Neu set gia tr TI,TD en gia tr 0.0 th ban se thu c mot bo ieu khien Ptai iem hoat ong

Tng bc ap ng trong mien thi gian la:LMN_Sum(t):la bien tong trong cheo t ong cua bo ieu khienER (0) : la s thay oi tng bc cua sai so a c chuan hoaGAIN : o li cua bo ieu khienTI : thi gian tch phanTD :thi gian vi phanD_ :he so vi phan

Hnh 5.7. Minh hoa cac thong so cua thuat toan PID

Bo tch phan (TI, I_ITL_ON, I_ITLVAL)Trong ieu khien tay no c ieu chnh nh sau:LMN_I = LMN - LMN_P - DISV.

Neu bien van hanh (manipulated variable) b gii han th c cau I se b ngnghoat ong. Neu sai so a c cau I tr ve trong khoang cho phep cua bien



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van hanh th c cau I co the c thay oi bang cach: c cau I cua bo ieukhien co the c kch hoat bi TI = 0.

S hoat ong cua c cau P se b yeu i khi co s thay oi cua iem setpoint.S hoat ong cua c cau P se b yeu i khi co s thay oi cua iemsetpoint(PFAC_SP)e ngan chan s qua tam(vt qua gii han),ban co the lam giam s hoatong cua c cau P bang cach s dung he so t le oi vi s thay oi cuaiem setpoint, thong so PFAC_SP. S dung PFAC_SP, ban co the chon cacgia tr lien tiep t 0.0 1.0 e quyet nh hieu qua cua c cau P khi iemsetpoint thay oi.- PFAC_SP=1.0: c cau P b anh hng neu iem setpoint b thay oi.

- PFAC_SP=0.0: c ca u P hoan toan khong b thay oi neu iem setpoint bthayoi.

Viec giam a nh hng cua c cau P se at c bang s can bang themc cau I

Cac nhan to cua c cau vi phan(TD, D_F)C cau D cua bo ieu khien se b giam kch hoat vi TD = 0.Neu c cau D c kch hoat ,theo moi quan he gia cac thong so ta co:TD = 0.5 * CYCLE * D_F

Cai at thong so cua bo ieu khien P va PD vi iem ang hoat ongTrong giao dien cua ngi s dung, c cau I khong c kch hoat (TI = 0.0)va c cau (TD = 0.0) cung vay. Sau o cai at cac thong so:I_ITL_ON = TRUEI_ITLVAL = iem ang hoat ong.ieu khien hoi tiep (DISV)Bien hoi tiep co the c them vao trong ngo vao DISVViec tnh toan bien van hanhS o khoi di ay la s o ve s tnh toan bien van hanh



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Hnh 5.8. S o khoi tnh toan bien van hanh

Vung ieu khien (CONZ_ON, CON_ZONE)Neu CONZ_ON = TRUE, bo ieu khien se hoat ong trong vung ieukhien. ieu nay co ngha la bo ieu khien hoat ong theo thuat toan sau:- Neu PV vt qua gia tr SP_INT gan can tren cua CON_ZONE, th gia tr

LMN_LLM la gia tr ngo ra nh bien van hanh (ieu khien theo chu trnhkn)

- Neu PV nam di gia tr SP_INT gan can di cua CON_ZONE,th gia trLMN_HLM la gia tr ngo ra nh bien van hanh(ieu khien theo chu trnhkn)

- Neu PV nam trong khoang vung ieu khien (CON_ZONE) bien van hanhse gi gia tr cua no la i t LMN_Sum cua thuat toan.Chu y: S chuyen oi t ieu khien kn sang ieu khien t ong theo chutrnh kn th s ieu khien se tnh toan 1 khoang tre khoang 20% cua vungieu khien.

Hnh 5.9. S o vung ieu khien (CONZ_ON, CON_ZONE)

Trc khi kch hoat vung ieu khien tay, phai chac chan rang vung ieukhien khong qua hep, neu vung ieu khien qua nho, s dao ong se xuathien trong bien van hanh va bien x l.Thuan li cua vung ieu khien



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Khi gia tr x l thuoc vung ieu khien , c cau D tao ra mot s giam ccnhanh cua bien van hanh. ieu nay co ngha la vung ieu khien ch hu ch

khi c cau D c kch hoat. Khong co vung ieu khien, ve c ban c cau Pse lam giam bien van hanh. Vung ieu khien se co tac ong ti s on nhnhanh hn ma khong co s vt qua gii han hoac sai lech di( thap hn trso danh ngha).X l gia tr bang tay (MAN_ON, MAN)Ban co the bat cong tac ieu khien tay hoac t ong . Trong ieu khien taybien van hanh c ieu chnh en mot gia tr theo hng dan .C cau tch phan (INT) c set en gia tr LMN - LMN_P DISVva c cauvi phan (DIF) c set en gia tri 0 va c ong bo hoa ben trong. Do o

chuyen sang che o t ong se t b va cham hn.Chu y: trong khi ieu khien thong so MAN_ON khong co anh hng g.S gii han cua bien van hanh LMNLIMIT (LMN_HLM, LMN_LLM)Gia tr cua bien van hanh c gii han en 2 gia tr gii han LMN_HLM vaLMN_LLM bi ham LMNLIMIT. Neu s gii han nay at c, ieu nayc ch nh bi bit thong tin QLMN_HLM va QLMN_LLM. Neu bien vanhanh b gii han th c cau se b ngng hoat ong. Neu sai so a c cau I veung vung bien van hanh th c cau I se c phuc hoi.Tay oi s gii han cua bien ket qua

Neu mien bien van hanh b giam va gia tr mi khong c gii han cua bienvan hanh nam ngoai khoang gii han, th c cau I va gia tr cua bien vanhanh se b thay oi.Viec tieu chuan hoa bien van hanh (LMN_FAC, LMN_OFFS)Ham LMN_NORM chuan hoa bien van hanh theo cong thc sau:LMN = LmnN * LMN_FAC + LMN_OFFS

No c dung vi y nh:LMN_FAC: nh he so cua gia tr x l.LMN_OFFS: s offset cua gia tr x l.

Gia tr bien van hanh cung co kha nang c nh dang t ben ngoai.Ham CRP_OUT chuyen so thc sang gia tr ngoai vi theo cong thc sau:LMN_PER = LMN * 27648/100Vi gia tr mac nh (LMN_FAC = 1.0 va LMN_OFFS = 0.0) th s chuanhoa se khong c thch hp. Luc nay ket qua cua bien van hanh la ngo ratai LMN.

Ghi nhan va chuyen tai cac thong so cua bo ieu khien- Viec ghi nhan cac thong so cua bo ieu khien SAVE_PAR



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Neu viec cai at cac thong so hien hanh c dung, ban co the ghi nhanchung vao mot cau truc ac biet trong ham FB 58"TCONT_CP" trc khi tao

ra mot s thay oi .Neu ban ieu chnh bo ieu khien, viec cac thong so ghinhan c viet e len thay gia tr trc khi chuyen oi.PFAC_SP, GAIN, TI, TD, D_F, CONZ_ON va CONZONE c chuyen sangcau truc PAR_SAVE.- Viec tai cac thong so a c ghi nhan cua bo ieu khien UNDO_PARHam nay c s dung e kch hoat thong so c cai at cuoi cung cua boieu khien ma ban a ghi nhan e phuc hoi bo ieu khien (ch trong ieukhien tay)

Hnh 5.10. S o khoi cua viec ghi nhan va chuyen tai cac thong so cua boieu khien

Viec chuyen oi cac thong so gia bo PI va PID LOAD_PID (PID_ON)Theo qua trnh ieu chnh cac thong so PID va PI se c lu vao trong cautruc PI_CON va PID_CON. Tuy vao PID_ON,ban co the s dungLOAD_PID trong ieu khien tay oi vi cac thong so PI hoac PID e tao racac thong so cua bo ieu khien

Chu y:Cac thong so cua bo ieu khien ch c ghi tr lai vao bo ieu khien viUNDO_PAR hoac LOAD_PID khi o li cua bo ieu khien khac 0.LOAD_PID copy cac thong so neu o li GAIN 0 (cac thong so cua mottrong hai bo PI va PID )D_F, PFAC_SP co the c set en gia tr mac nh bang cach ieu chnh.Nhng gia tr nay sau o co the c xac nh bi ngi ieu chnh.LOAD_PID khong thay oi cac thong so nay.Vi LOAD_PID vung ieu khien luon c tnh toan lai.



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(CON_ZONE = 250/GAIN) ngay khi CONZ_ON = FALSE c set.

Qua trnh chay (Tuning) cua FB 58 "TCONT_CP" Gii thieuVi viec ieu khien viec chay t ieu chnh cua "TCONT_CP", bo ieu

khien PI/PID cap nhat t ong cac thong so cua bo ieu khien. Co haiphng thc chay Tuning:

- Chay t ieu chnh bang s tien gan ti iem hoat ong vi s thay oitng bc cua iem at.

- Chay t ieu chnh iem hoat ong bang viec at mot bit bat au.Ca hai cach tren, qua trnh x l c kch thch bi co the la chonbien gan thay oi. Sau khi ch ra iem uon, cac thong so bo ieu khienco gia tr va bo ieu khien c khi hoat ong t ong va tiep tucieu khien vi nhng thong so nay.Ban co the ieu khien viec chay ieu chnh bang viec s dung cacthong so c thiet lap tren giao dien chng trnh thiet ke.Cac bc tien hanh:

- Start -> Simatic Manager -> Project -> Block -> DB58 -> Option ->Curve Recorder

Hnh 5.11. Man hnh cap nhat o th

-Thiet lap cac thong so vao sau khi vao Curve Recorder nhap vaoSetting( cai at thong so )



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Hnh 5.12. Man hnh cai at thong so-Sau khi cai at thong so xong ta vao Data Block -> Open Oline ->

Option Controller Tuning

Ket quaCac thong so ieu khien c cap nhat trong qua trnh FB58"TCONT_CP" chay t ieu chnh.Nhan to e lam giam thong so tac ong P la PFAC_SP = 0.8- o li cua bo ieu khien GAIN

- Thi gian bo tch phan: TI- Thi gian bo vi phan: TD- Nhan to bo vi phan: D_F = 5.0- Vung ieu khien Control zone on/off: CONZ_ON- o rong vung Control zone: CON_ZONE

Hnh 5.13. o th ket qua cua qua trnh cap nhat thong so

V du ve lam giam ap ng ieu khien vi PFAC_SPThong so qua trnh:

GAIN = 6T1 = 50sT2 = 5s

Thong so bo ieu khien:



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GAIN = 6TI = 19.6s

Bang 5.2: Chu thch ket qua cua o th

5.2.2 Cac thong so cua FB58

ACH

THONGSO

IN/OUT KIEUDLIEU

VUNGGT

GTAU

MO TA

0.0 PV_IN INPUT REAL Tuycambien sdung

0.0 PROCESS VARIABLEIN.Gia tr khi tao co the

at au vaoprocessvariable on hoac tbien qua trnh cbieu dien di dang sothc dau phay ong

4.0 PV_PER INPUT INT 0 PROCESS VARIABLEPERIPHERYBien qua trnh c noivi CPU thong quacong vao tng t.

6.0 DISV INPUT REAL 0.0 DISTURBANCEVARIABLEoi vi ieu khienthuan bien nhieu se

Thigianth

He soSP

Chu thch o vot lo

8:18 1.0 C cau P khong co s hoi tiep 32%8:19 0.8 C cau P co s hoi tiep 20%, s

ap ng ieu khien ieu kientot nhat

2%

8:20 0.0 C cau P hoi tiep hoan toan, schan ong giam manh.

-



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c noi ngo vaodisturbance variable

10.0 INT_HPOS INPUT BOOL FALSE INTEGRAL ACTIONHOLD IN POSITIVEDIRECTION .Ngo ra cua c cau I cothe c ch ra trongmot pham vi trc tiep.e at c ieu nay,ngovao INT_HPOSphai c set en gia

tr TRUE . Trong tngt ieu khien,INT_HPOS cua bo ieukhien au tien c ketnoi en ngoQLMN_HLM cua boieu khien th 2

10.1 INT_HNEG

INPUT BOOL FALSE

INTEGRAL ACTIONHOLD IN NEGATIVE

DIRECTION.Ngo ra cua c cau I co

the c ch ra trongmot hng phu nh.e at c ieu nay,ngo vao INT_HPOSphai c set en giatr TRUE . Trong tngt ieu khien,

INT_HPOS cua bo ieukhien au tien c ketnoi en ngoQLMN_LLM cua boieu khien th 2

12.0 SELECT INPUT INT 0EN3

0 SELECTION OF CALLPID AND PULSEGENERATOR.



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Neu may phat sungc kch hoat, co mot

vai cach e goi thuattoan PID va bo phatsung.SELECT =0: Bo ieukhien se c goi trongmot chu k nhanh mco gian oan, thuat toaPID va bo phat sung sec x l.

SELECT =1:Bo ieukhien se c goi trongkhoi OB1 va ch thuattoan PID c x l.SELECT = 2: bo ieukhien se c goi trongmot chu k nhanh mco gian oan va ch bophat sung c x l.

SELECT =3: Bo ieukhien se c goi trongmot chu k cham mco gian oan va chthuat toan PID c xl.

14.0 PV OUTPUT

REAL Tuycambien s

dung

0.0 PROCESS VARIABLETn hieu qua trnh cxuat qua cong ra

process variable18.0 LMN OUTPU

TREAL 0.0 MANIPULATED

VARIABLEGia tr ra c thiet lapbang tay thong quacong ra manipulatedvariable

22.0 LMN_PER OUTPU INT 0 MANIPULATED



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T VARIABLEPERIPHERY.

Gia tr au ra thiet lapbang tay theo kieu bieudien phu hp vi caccong vao/ra tng tc chon qua ngoramanipulated variableperiphery

24.0 QPULSE OUTPUT

BOOL FALSE

OUTPUT PULSESIGNAL.

Khi co gia tr xungc kch hoat th se cotn hieu ra tai ngo raQPULSE

24.1 QLMNHLM

OUTPUT

BOOL FALSE

HIGH LIMIT OFMANIPULATEDVARIABLEREACHED.Cong ra hight limit of

manipulated variablereached thong bao giatr cua bien qua trnhvt qua gia tr giihan

24.2 QLMN_LLM

OUTPUT

BOOL FALSE

LOW LIMIT OFMANIPULATEDVARIABLEREACHED

Cong ra low limit ofmanipulated variablereached thong baogia t cua bien qua trnhnho hn gia tr gii han

24.3 QC_ACT OUTPUT

BOOL TRUE NEXT CYCLE, THECONTINUOUSCONTROLLER IS



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WORKING.Thong so nay se c

ch ro khi co hay khongtrang thai ieu khientiep theo se c thihanh tai lan goi tieptheo (ch thch hp khiSELECT co gia tr 1hoac 0)

26.0 CYCLE INPUT/OUTPU

T

REAL 0.001s

0.1s SAMPLE TIME OFCONTINUOUS

CONTROLLER[s].Tai ay se set thi gianmau oi vi thuat toanPID. Bo ieu chnhtrong pha th nhat vaa vao CYCLE. Thigian lay mau la khoangthi gian khong oigia cac lan khoi c

cap nhat.30.0 CYCLE_P INPUT/

OUTPUT

REAL 0.001s

0.02s SAMPLE TIME OFPULSEGENERATOR[s].Tai ngo vao nay, bana vao thi gian mauoi vi may phat xung.FB 58 TCONT_CPtnh toan thi gian mau

trong pha th nhat vaa no vao trongCYCLE_P.

34.0 SP_INT INPUT/OUTPUT

REAL vunggia trcua giatr x l

0.0 INTERNALSETPOINTau vao internalsetpoint c s dunge thiet lap tn hieu chu



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ao.38.0 MAN INPUT/

OUTPUT

REAL 0.0 MANUAL VALUE.

Cong vao manualvalue c s dung eat gia tr bang cacham giao dien

42.0 COM_RST INPUT/OUTPUT

BOOL FALSE

COMPLETERESTARTKhoi co chc nang khitao lai he thong hoantoan khi au vao

complete restart cthiet lap gia tr logicTRUE

42.1 MAN_ON INPUT/OUTPUT

BOOL TRUE MANUALOPERATION ON.Khi au vao manualoperation on co gia trlogic TRUE mach vongieu khien se b ngat,

cac gia tr se c thietlap bang tay.

90.0 PVPER_ON

INPUT BOOL FALSE

PROCES VARIABLEPERIPHERY ONNeu ban muon gia trx l c oc thongqua thiet b I/O, ngovao PV_PER phai cket noi en I/O va gia

tr x l ngoai vi phaic set len (TRUE).

186.5 LOAD_PID

INPUT/OUTPUT

BOOL FALSE

LOAD OPTIMIZEDPI/PID PARAMETERS

186.6 PID_ON INPUT/OUTPUT

BOOL FALSE

PID MODE ONPID controller:PID_ON = TRUE



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PI controller:PID _ON = FALSE

5.3 HAM FC105, FC106e thuat li trong qua trnh x ly cac tn hieu tng t phan mem Step 7 co sanham th vien FC105,FC106

5.3.1 Ham FC105_nh t le ga tr ngo vao Analog

Hnh 5.14. Cac cau lenh cua ham FC105

- V du: Mc ay trong bon c o bang lt .Bochuyen oi o c chon 500 lt th tng ng

vi mot gia tr o la 10V.- T le: Module Analog chuyen oi gia tr analog

10V thanh so nguyen 27 648. Gia tr nay baygi a c chuyen oi thanh ai lng vat l lt.Qua trnh nay ngi ta goi la nh t le gia trAnalog.

- Chng trnh:Viec nh t le gia tr analog cthc hie trong khoi chuan FC 105. Khoi FC 105 nam trong th vien Standard Librarytrong chng trnh S7TI-S7 Converting Block cua

phan mem Step 7.- IN : Gia tr Analog tai ngo vao IN co the c oc trc tiep t module

hoacoc qua ngo giao tiep d lieu trong dang INTEGR

- LO_LIM,HI_LIM: Cac gii han chuyen oi cac ai lng vat l se cat

trc cac ngo vao LO_LIM (gii han di) va HI_LIM (gii hantren). Trong th du tren th gii han chuyen oi t 0 en 500 lt.



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- OUT: Gia tr t le (ai lng vat l) th c lu tr nh la mot so thc taingo

ra OUT.

Hang so K1, K2 se c set da tren gia tr ngo vao la BIPPOLAR hayUNBIPPOLAR

- BIPPOLAR: Ngo vao BIPPOLAR xac nh lieu gia tr am co cchuyen oi

hay khong.BIPPOLAR: Gia tr ngo vao la so nguyen c tha nhan gia -27648va +27648,do o K1 la -27648, K2 la +27648.

UNBIPPOLAR: Gia tr ngo vao la so nguyen c tha nhan gia 0va +27648,do o K1 la0, K2 la +27648.

Trong v du tren, bit nh 0.0 co tn hieu 0 va v the bao hieu gia tr ngovao la mot cc.

- RET_VAL: Ngo ra RET_VAL co gia tr 0 neu s hoat ong khong co sco.

Neu gia tr tai ngo vao ln hn K2 , ngo ra OUT c kiem soat biHI_LIM va loi xuat hien, neu gia tr tai ngo vao nho hn K1 , ngo ra OUTc kiem soat bi LO_LIM va loi xuat hien. Luc nay ENO se c set

gia tr 0, va RET_VALse co gia tr W#16#0008.

5.3.2 Ham FC106_Khong chia t le so thc cho ngo ra Analog

Hnh 5.15. Cac cau lenh cua ham FC106



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V du: Chng trnh tnh toan gia tr Analogtrong

pham vi t 0 en 100.0%. Gia tr nay cchuyen ti ngo ra nh mot module ngo raAnalog.

- Khong chia t le: Khoi chuan FC106 c sdung

cho viec khong chia t le (s bien oi cua motso thc t 0 en 100.0% thanh mot so nguyen16 bits t 0 en 27648)

- OUT:Gia tr Analog khong chia t le tai ngo ra out co the c tryen i

didang mot so nguyen 16 bits en ngo giao tiep d lieu hoac trc tiep enngoai vi.

Chng trnh: Khoi FC106 nam trong th vien Standard Library trong chngtrnh S7 TI-S7 Converting Block cua phan mem Step7.

5.4 V du ng dung ieu khien mc nc trong bon5.4.1 Nguyen Ly hoat ong :

Nc c bm t bnh cha 1 len bnh 2 bang bm ly tam ,bm ly tamhoat ong theo hai che o co the ieu khien bang tay hoac ieu khien t PLCbang num chuyen hai che o AUTO va MAN, bm hoat ong hieu ien thexoay chieu 220-240 VAC ,cong suat la 30 W, lu lng nc khoang 20lt/phut, no c tac ong bi 2 rle(250 VAC/5A). Dong nc qua bm chialam 2 phan, 1 lng se qua van solenoid va 1 lng c hoi ve be 1 e baoam an toan cho bm khi van solenoid ong lai. Van solenoid cung co the cieu khien bang tay hoac bang PLC dung e ong m tc thi dong nc lenbon cha 1 khi ieu khien. Ap suat hoat ong t 0-10 bar, cap dong 24 VDC,dong co the c cap t rle hoac trc tiep t PLC.

Dong tiep tuc qua bo phan hien th lu lng dong c kh dung e ieu chnhlu lng sao cho va phai on nh gia 2 luong nc phan nhanh t bm. Khi qua bochuyen oi lu lng bo phan nay se hien th gia tr lu lng dong chay chnh xacva truyen thong so nay ve cho PLC x ly di dang dong ien t 0/4 20 mA tuytheo gia tr ln nho cua lu lng nc.

PLC nhan 2 ngo vao analog la bo chuyen oi lu lng va cam bien, tuy thuoc vaochng trnh phan mem ieu khien c viet san ma PLC se ieu khien proportional



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vale( vale ieu khien ty le ) e ong m gop m cua van . Do o lu lng nc sec ieu khien 1 cach ty le vi dong ma PLC xuat ra t ngo ra AO.

Hnh 5.16. S o khoi ieu khien mc nc.

5.4.2S o khoi cua he thong t ong

Hnh 5.17. S o khoi cua he thong t ong

P S C P U D I D O A O AI

BO O M C

BO O

LNG

V3

ON/OF FB M

V2 (0%-100 %)Van tuye n t nh

LIS1

V 1

ON/OFF

4-20mA

PQW288 P IW272

Start/

Stop

I0.0

I0.1

4-20mA

1-1

00cm

V 4

Van xa

Bo n 1

Bo n 2

Q0.2

Q0.1

PVFuzzycontrol Bon nc 2

Cam bien

-

SP

N

+ + +ess

PID(FB58)

Cam bieno mc



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PID control: c ieu khien thong qua cuc PLC

Bon nc 2:la oi tng ieu khienCam bien o : cam bien o mc nc da vao ap lc e len be mat t 0 0.1 bar ea ra dong va ap tng ng t 4-20mATn hieu nhieu ess do tac ong cua van xaTrong o : SP : la gia tr t nhap vao (c nhap vao t ben ngoai ).PV : la gia tr hien tai co trong bon nc (gia tr c oc t vung nh vao analog)Ta lay gia tr hien tai PV so vi

GT-plc-S7-300

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Transcript of GT-plc-S7-300