ind sys i protokoli - plc primeri primene (predavanja)

Programabilni logiki kontroleri PLC

Industrijski sistemi i protokoli -predavanje 4

Ver 2009.2

1. Mirno i radno, tasteri, kontakti i PLC bitovi2.Ladder dijagram za programiranje PLC3. Blokovi Ladder dijagrama 4. Primeri Ladder dijagrama 5. Primena u elektromotornim pogonima

Sadraj

PLC 2/30

Tasterita je radno stanje, akcija, nenormalno stanje kod tastera? To je pritisak na taster!

Radni tester vodi u radnom stanju, a normalno (kada ga ne pritiskamo) je otvoren normalno otvoren. Tako mu definie i sam grafiki simbol i NO.

Normalno otvoren (radni) i zatvoren (mirni)?

PLC 3/30

otvoren. Tako mu definie i sam grafiki simbol i NO.

Mirni tester vodi u neradnom stanju, koje je normalnojer ga ne pritiskamo , on je normalno zatvoren. Tako mu definie i sam grafiki simbol i NC.

Sutina ovde je da su vas pogreno uili

1) da je normalno da ne radimo.

2) da smo mirni samo kad ne radimo.

Rele


1

2

A1

A2

Kontaktor

12 radni (NO)

313 mirni (NC)

PLC 4/30

1

2

A1

A2

3

4

5

6

Kontaktor

glavni kontakti

namotaj elmagneta(pulna)

13

14

21

22

pomonikontakti

Moderni kontaktori


PLC 5/30

Princip rada kontaktora


Nema napona na namotaju, el.magnet ne radi, nema privlaenjakotve, kontakti razdvojeni.

PLC 6/30

Napon na namotaju ,elmagnetPrivlai se kotva, kontakti zatvoreni

Kontakti releja ili kontaktorata je radno stanje, akcija, nenormalno stanje kod releja/kontakotora? To je napon na pulni !Radni kontakt vodi u radnom stanju, a normalno (kada nema komande) je otvoren normalno otvoren. Tako mu definie i sam grafiki simbol i NO.

Mirni kontakt vodi u neradnom stanju, koje je


PLC 7/30

Mirni kontakt vodi u neradnom stanju, koje je normalno jer kad nema napona, on je normalno zatvoren. Tako mu definie i sam grafiki simbol i NC.

Eneg. ka mrei

Energ. ka potroau

pulna(komanda)

pomoni mirni (NC,12)

pomoni radni (NO, 34)

Bitovi u PLCta je radno stanje, akcija, neaktivno, nenormalno stanje kod bitova ? To je stanje 1, stanje ON !

Radni bit vodi u radnom stanju (1), a normalno (kada nije 1) je otvoren normalno otvoren kontakt.

Mirni bit vodi u neradnom stanju (0),normalnom stanju on je normalno zatvoren kontakt.


PLC 8/30

Mirni bit vodi u neradnom stanju (0),normalnom stanju on je normalno zatvoren kontakt.

Bit moe biti ulaz (na primer I0.0) koji je 1 ako je napon na ulazu, ili izlaz (na primer Q0.0) koji je 1 akoje napon na izlazu, ili ak i samo bit iz memorije (naprimer M0.0) koji je 1 ako je prethodno setovan ili 0ako je prethodno resetovan.

Primeri sa PLC Ladder dijagramima

Nain programiranja PLC Siemens S7

Lestviasta logika (ladder logic) je nain crtanja el. logikih ema. To je grafiki jezik, veoma popular kod PLC. Originalno je izmiljen da zameni relejnu logiku. Ime je dobio jer program podsea na merdevine.

PLC 10/30

LD start_tasterO izlazA stop_taster= izlaz

Alternativa STL (statment list) - Instruction List language

Nain programiranja PLC Siemens S7

Stara relejna ema(napajanje, ice, pulne, mirni i radni kontakti releja)

Lestviasti PLC programikoji zamenjuju ovu emu

PLC 11/30

PLC S7-200 ciklus izvrenja programa

PLC 12/30

PLC: Osnovni blokovi Ladder dijagrama

PLC S7 - tipovi podataka , bitovi i bajtovi

PLC 14/30

PLC S7 - tipovi podataka , word i double word

PLC 15/30

PLC S7 osnovni Ladder blokovi - Kontakti

The Normally Open contact is closed (on) when the bit is 1.The Normally Closed contact is closed (on) when the bit is 0.

Rade sa ulaznim bitovima I0.0 .. Izlaznim bitovima Q0.0.. i memorisanim bitovima M0.0 ...

PLC 16/30

Radi sa Izlaznim bitovima Q0.0.. i memorisanim bitovima M0.0 ...

The Set (S) and Reset (R) instructions set (turn on) or reset (turn off) the specified number of points (N), starting at the specified address (Bit). Tipically, N=1. You can set or reset from 1 to 255 points. If the reset specifies either a timer bit (T)

PLC S7 osnovni Ladder blokovi set/reset

PLC 17/30

reset specifies either a timer bit (T) or counter bit (C), the instruction resets the timer or counter bit and clears the current value of the timer or counter.

Dodela vrednosti , MOV instrukcija

The Move Byte (MOVB) instruction moves the input byte (IN) to the output byte (OUT) without changing the original value.

The Move Word (MOVW) instruction moves the

PLC S7 osnovni Ladder blokovi MOV

PLC 18/30

The Move Word (MOVW) instruction moves the input word (IN) to the output word (OUT) without changing the original value.

Ove dve instrukcije ete esto koristiti da podesite neki komunikacioni modul povezan sa , ili unutar PLC ! Na primer registar za baud rate postavi na 9600 !IN poveemo sa 9600 i povuemo liniju ka EN (dozvolimo upis)

Kontrola toka programa , FOR and NEXT

The FOR (FOR) instruction executes the instructions between the FOR and the NEXT. You specify the index value or current loop count (INDX), the starting value (INIT), and the ending value (FINAL). The NEXT (NEXT) instruction marks the end of the FOR loop, and sets the top of the stack to 1.

PLC S7 osnovni Ladder blokovi FOR and NEXT

PLC 19/30

loop, and sets the top of the stack to 1.

Kontrola toka programa , JMP and LBL

The Jump to Label (JMP) instruction performs a branch to the specified label (n) within the program. When a jump is taken, the top of stack value is always a logical 1.LBL is the program jump point.

PLC S7 osnovni Ladder blokovi JMP and LBL

PLC 20/30

PLC S7-200 podprogram (subroutine)

When the main program calls the subroutine for execution, the subroutine carries out its program to its end. Then, the system returns control to the main program at the network from which the subroutine was called.

PLC 21/30

Call Parameter Type DescriptionIN Parameters are passed into the subroutine. If direct address (such as VB10),

the value at the specified location is passed into the subroutine. If data constant (16#1234), or an address (&VB100), the constant or address value is passed into the subroutine.

IN_OUT The value at the specified parameter location is passed and the result value fromthe subroutine is returned to the same location.

OUT The result value from the subroutine is returned to the specified parameter location. TEMP Any local memory that is not used for passed parameters may be used for temporary

storage within the subroutine.

S7-200 PLCs incorporate instructions for use with interrupts.

Interrupts are used to initiate a specific, short PLC programsegment, called an interrupt routine, when an internal orexternal event occurs. After the interrupt routine has beenexecuted, control is returned to the main program.

Three types of interrupts are supported by S7-200 PLCs, communication port interrupts, I/O interrupts,

PLC S7-200 Prekid (interrupt)

PLC 22/30

I/O interrupts, timebased interrupts.

Communication port interrupts are used to control a communication port operated in Freeport mode.I/O interrupts are used to respond quickly to high-speed I/Otransitions, such as those associated with high-speed countersor pulse train outputs. Time-based interrupts allow the user program to execute an interrupt routine on a cyclic basis.

Each of these types of interrupts has an associated priority that determines which interrupt is processed first in the event that two or more interrupts are requested at the same time.Communication port interrupts have the highest and time-based have the lowest priority.

Prekid se opsluuje nezavisno od periodinog PLC ciklusa skeniranja.

Kod prekida treba definisati dve stvari Izvor prekida Podprogram koji treba izvriti kada se desi prekid


PLC 23/30

Te dve stvari treba spojiti, ATTACH blok !ATTACH blok kae pridrui ovaj podprogram (interrupt routine) sa onim interuptom ili dogaajem (event)

Prekid treba dozvoliti (ENI ) ili zabraniti (DISI)

The Enable Interrupt (ENI) instruction globally enables processing of all attached interrupt events.

The Disable Interrupt (DISI) instruction disables processing of all interrupt events.


ATCH trai i ime podprograma za izvrenje, koji treba povezati sa tim dogaajem

ATCH trai broj dogaaja tj prekida

PLC 24/30

The Attach Interrupt (ATCH) instruction associates an interrupt event (EVNT) with an interrupt routine number (INT), and enables the interrupt event.

The Detach Interrupt (DTCH) instruction disassociates an interrupt event (EVNT) from all interrupt routines, and disables the interrupt event.

prekida

DTCH odvaja dogaaja od svih rutina. Ne mora da zna koja je bila priljuena tom dogaaju, sve ubija !


Tabela Event-aza PLC S200(nepotpuna)

PLC 25/30

PLC S7-200 Osnovni blokovi Ladder dijagrama

Floating point matematika

IN1 + IN2 = OUT

IN1 - IN2 = OUT(nije prikazano)

PLC 26/30

IN1 * IN2 = OUT

IN1 / IN2 = OUT

Itd..

PLC: Timer and Counter

PLC S7-200 tajmerski blokovi

This timer continues counting after the Preset is reached, and it stops counting at the

The On-Delay Timer (TON)instruction counts time when the enabling input is ON. When the current value (Txxx) is greater than or equal to the preset time (PT), the timer bit is ON.The On-Delay timer current value is cleared when the enabling input is OFF.

PLC 28/30

This timer continues counting after the Preset is reached, and it stops counting at the maximum value of 32767.TON, TONR, and TOF timers are available in three resolutions. The resolution is determined by the timer number as shown in the chart below. Each count of the current value is a multiple of the time base. For example, a count of 50 on a 10-ms timer represents 500 ms.

Timer Type Resolution Maximum Value Timer NumberTONR 1 ms 32.767 s T0, T64

10 ms 327.67 s T1-T4, T65-T68 100 ms 3276.7 s T5-T31, T69-T95

TON, TOF 1 ms 32.767 s T32, T96 10 ms 327.67 s T33-T36, T97-T100 100 ms 3276.7 s T37-T63, T101-T255


The On-Delay Timer (TON)instruction counts time when the enabling input is ON. When the current value (Txxx) is greater than or equal to the preset time (PT), the timer bit is ON.The On-Delay timer current value is cleared when the enabling input is OFF.

PLC 29/30

The On-Delay Timer (TON) time diagram


The Retentive On-Delay Timer (TONR)instruction counts time when the enabling input is ON. When the current value (Txxx) is greater than or equal to the preset time (PT), the timer bit is ON.The current value of the Retentive On-Delay timer is maintained when the input is OFF. You can use the Retentive On-Delay timer to accumulate time for multiple periods of the input ON. A Reset instruction (R) is used to clear the current value of the TONR.

PLC 30/30


The Off-Delay Timer (TOF) is used to delay turning an output OFF for a fixed period of time after the input turns OFF. When the enabling input turns ON, the timer bit turns ON immediately, and the current value is set to 0. When the input turns OFF, the timer counts until the elapsed time reaches the preset time. When the preset is reached, the timer bit turns OFF and the current value stops counting. If the input is OFF for a time shorter than the preset value, the timer bit

PLC 31/30

shorter than the preset value, the timer bit remains ON. The TOF instruction must see an ON to OFF transition to begin counting.

PLC S7-200 brojaki blokovi (counter Down)

The Count Down (CTD) counts down from the current value of that counter each time the count down input CD makes the transition from off to on. When the current value Cxxx is equal to zero, the counter bit (Cxxx) turns on. The counter resets the counter bit (Cxxx) and loads the current value with the preset value (PV) when the load input (LD) turns on. The Down Counter stops counting when it reaches zero, and the counter bit Cxxx turns on.

PLC 32/30

Counter Down time diagram

PLC S7-200 brojaki blokovi (counter)The Count UP Down (CTUD) counts up each time the count-up input CU makes the transition from off to on, and counts down each time the count-down input CD makes the transition from off to on. The current value Cxx of the counter maintains the current count. The preset value PV is compared to the current value each time the counter instruction is executed. Upon reaching maximum value (32,767), the next rising edge at the count-UP input causes the current count to wrap around to the

PLC 33/30

the current count to wrap around to the minimum value (-32,768). On reaching the minimum value (-32,768), the next rising edge at the count-DOWN input causes the current count to wrap around to the maximum value (32,767). When the current value Cxx is greater than or equal to the preset value PV, the counter bit Cxx turns on. Otherwise, the counter bit turns off. The counter is reset when the Reset (R) input turns on.

PLC S7-200 brojaki blokovi (counter)

The Count Up (CTU) instruction counts up from the current value each time the count-up input CU makes the transition from off to on. When the current value (Cxxx) is greater than or equal to the Preset Value (PV), the counter bit (Cxxx) turns on. The counter is reset when the Reset (R) input turns on, or when the Reset instruction is executed. The counter stops counting when it reaches the maximum value (32,767).

PLC 34/30

Primeri Ladder dijagrama

PLC S7-200 samodranje

Pritisnut normalno otvoren start_taster i nepritisnut normalno zatvoren stop_taster ukljuuju izlaz.Zatim , izlaz samog sebe dri sve dok neko ne pritisne stop_taster

PLC 36/30

Ovo vai u sluaju da se koriste dva radna tastera.

start_taster

stop_taster

24 V

I0.1

I0.2

PLC

PLC S7-200 samodranje industrija

Pritisnut normalno otvoren start_taster i nepritisnut (aliprovodan) normalno otvoren stop_taster ukljuuju izlaz.Zatim , izlaz samog sebe dri sve dok neko ne pritisne stop_tasterOvo vai u sluaju da se za stop koriste mirni taster!

PLC 37/30

Ovo vai u sluaju da se za stop koriste mirni taster! Na primer, podnaponska sklopka dok ima napona dri stopprovodnim, ako napon nestane, stop izbacuje pogon.

start_taster

stop_taster

24 V

I0.1

I0.2

PLC

Primena PLC u pogonima

Primena PLC pri kontroli motora

ema pre pojave PLC

Logika je reena relejima,pulnama i pomonim kontaktima kontaktora (svi na razliitim naponima) kojisu povezani velikim brojemica. Promena logike

kontaktor

bimetal

napon

PLC 39/30

ica. Promena logikefunkcije i proirenja su bila gotovo nemogua.

CR rele (pulna i kontakt)M kontaktor-motor starter (pulna i trofazni energetski kontakti)OL trofazni bimetal i pomoni mirni kontakt) Start

tasterRele

napon


1. Motor starter, aktuator, prenosi snagu

Ovoga se neemo reiti ni sa PLC

2. Tasteri (HMI)

PLC 40/30

ALi, elimo da sve ostalo ( i mnogo vie) radi PLC

Primena PLC pri kontroli motora snaga

PLC 41/30

Komanda

(za novu komandu treba nam samo novi taster)

Logika

(lako se menja i proiruje po potrebi)


Tipovi lokalnih komanda ka PLC

Radni taster Normalno otvoren

Mirni taster Normalno zatvoren

Normalno otvoren

PLC 42/30

Normalno otvoren prekida

Normalno zatvoren prekida

Radni kontakt Normalno otvoren

Mirni kontakt Normalno zatvoren

+24V


PLC 43/30

Motor radi, Q0.0 se samodri, stop i bimetal nisu aktivni

Proirenje aplikacije svetlosni indikatori snaga

Dodatni svetlosni indikatori

PLC 44/30

Komanda

(za novu komandu treba nam samo novi taster)

Logika

(lako se menja i proiruje po potrebi)

Proirenje aplikacije svetlosni indikatori

PLC 45/30

Prosto reenje.

Novi kod i dve nove linije iz PLC

Motor starter

PLC 46/30

Druge aplikacije kontaktora i PLC

PLC 47/30

ind sys i protokoli - plc primeri primene (predavanja)

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