ace oplc presentation kurs

8/6/2019 ACE OPLC Presentation Kurs

1/44

ACE


2/44


3/44

ta je PLC ?

PLC je mikroprocesorski ureaj kojim se mogurealizovati upravljake, logike i sekvencijalne strukture,

koji zamenjuje relejna kola, vremenske relea, brojae i

analogne kontrolere.

PLC neprekidno proverava svoje ulaze i menja stanja

izlaze po apliciranom algoritmu.

Razvoj PLC, zapoet 1960-ih godina, pratio je zahteve

industrije sve do dananjice.


4/44

VentilRadni fluid

Senzor

0.00 Kg

Signal senzora

Vaga

Analogni ulazni

signal

Bocana traciOtvoriventil

Izlazni signal

1.50 Kg1.00 Kg0.50 Kg0.50 Kg1.00 Kg1.50 Kg0.00 Kg

Boca

puna

PLCPLC

ta je PLC ?

Programibilni Logiki

Kontroler

Mozak svake maine


5/44

VentilRadni fluid

Senzor

Vaga

Zatvori

ventil

Izlazni signal

0.00 Kg1.50 KgPLCPLC

ta je PLC ?


Kontroler

Mozak svake maine


6/44

VentilRadni fluid

Senzor

0.00 Kg

Signal senzora

Vaga

Analogni ulazni

signal

Boca natraciOtvoriventil

Izalazni signal

1.50 Kg1.00 Kg0.50 Kg0.50 Kg1.00 Kg1.50 Kg0.00 Kg

Boca

puna

PLCPLC

ta je PLC ?


Kontroler

Mozak svake maine


7/44

ta je PLC ?

IN CPU Memory OutHuman Machine Interface


8/44

Is a lamp an input or an output?

What about a temperature sensoris it an input or an

output?

Is a switch an input or an output?


9/44

Kako radi ?

PLC sadri 3 softverske komponente

Korisnika aplikacija

Operativni sistem

Bootstrap


10/44

Kako radi ?

Bootstrap program je osnovna rutina koja omoguava

uitavanje operativnog sistema.

Bootstrap program je softver koji je trajno instalisan na

PLC Flesh memoriji.N

jega upisuje proizvoa i korisnik gane moe menjati .

Prilikom izvravanja Bootstrap rutine, prepoznaje se

samo prvi serijski port PLC-a na baud rate od 9600.


11/44

Kako radi ?


Operativni sistem

Bootstrap


12/44

Kako radi ?

Operativni sistem PLCa je program koji koordinira

harverske resurse PLCa sa elementima korisnike

aplikacije.

Operativni sistem moe biti inoviran (update).

Operativni sistem korespondira sa aplikacijom preko

skupa sistemskih operanada (SB, SI, SL i SDW).


13/44

Kako radi ?


Operativni sistem

Bootstrap


14/44

Kako radi ?

A PLC works in application scans.

On every scan, the PLC checks the entire application,

and according to the Inputs and the logic, updates theOutputs.

The time it takes a PLC to scan the entire application is

called the PLC Scan time.


15/44

Call Sub x Call Sub y

Call Sub a

Ret

The PLC reads inputs from base and expansions

Writes to physical outputs and updates CANbus

Runs the HMI (including routines)

Handles Communication

Runs Ladder program

Ret

Ret Ret


16/44

What do you think ?

Can a change in the Scan time affect the performance

of the machine?

When a PC is on-line with a PLC, it can see the values

stored in the PLCs memory. At what stage in the Scan

do you think the values are determined?

In working with subroutines, do you think the Scan time

of the PLC is constant?


17/44

Kako radi ?

When we talk of the time it takes the PLC to execute apending operation, we have to take 3 parts into

consideration:

The time it takes it to run the logic

The time it takes the Output to actuallyaffect the machine

The time it takes the PLC to know the

Input exists

The response time

of the system


18/44

Kako radi ?

In order to allow some operations tohappen faster and decrease the response

time, the user can include Interrupts in the

Scan.

An Interrupt is a routine that will run at

every given time and allow the user to update

the status of specific Inputs and Outputs.

Working with Interrupts reduces the timedelays in the system and can improve results

when needed.


19/44

What do you think ?

Does an Outputs hardware type influence the response

time?

How can we make one part of the application run faster

than the others?

Can a change in the status of an Input be shorter than

the Scan time and still be recognized?


20/44

Ladder logic

The Unitronics Ladder logic tools

were build following the IEC 1131.6

In order to understand this standard

we need to know two things:

The Ladder editor is build out ofNets. Every Net should contain one

Rung.

The status of the elements in a

Net is determined according to the

status of them in the beginning ofthe Net.


21/44

Ladder logic


22/44

Ladder logic

Lets try to change the elements in the electric

circuit using Ladder Logic elements:


23/44

Ladder logic

Lets try to change the elements in the electric

circuit using Ladder Logic elements:


24/44

Ladder logic

Introduction: Basic LadderE

lements

Contact

A Contact is a representation of an Input

signal that we want to use as a energizing

condition for the rest of the Ladder net.

When the element linked to the Contact is

ON, we say that the Contact is closed. The

closed Contact allows the current to pass

through it.

The Contact can be linked toInputs,internal relays (MB), Timers, Counters, SBs

and Outputs.


25/44

Ladder logic

Contacts can also come in other forms.

One of the most common forms is the

Inverse Contact.

Inverse Contacts energize the net when

the element linked to it is OFF (logic 0).

Inverse Contacts are also called

Normally Closed Contacts.

Introduction: Basic LadderElements

Contact


26/44

Ladder logic

Two more types of frequently used

Contacts are Positive and Negative

Transitions.

A Positive (or negative) Transition

Contact is used to make sure something will

happen for only one scan.

A Positive Transition Contact is activated

when the element rises from OFF to ON,while a Negative Transition Contact is

activated when the element turns from ON

to OFF.


Contact


27/44

Ladder logic

CoilCoil

A Coil is a result of the rung. If all the

elements prior to the Coil are ON (logic 1)

the Coil will be energized. Once there wont

be a path of true conditions, the status of

the Coil will also change to logic 0 (low).

A Coil can be linked to Outputs, internal

coils and SBs.

Due to the way a PLC scans, a directCoil should be called only once in the

program.



28/44

What do you think ?

Make the same Output turn ON only when you press

two keys at the same time.

Lets do a simple application that turns an output ON

when you press one of the keys on the PLC.

Now, make the Output turn ON when you are not

pressing any key.


29/44

Ladder logic

You may need to latch the status of a

Coil, to make it stay in its current status

even if the conditions prior to it change. Wecan use the Set command for this purpose.

Once a Set command is given, the Coil

will stay ON till the next Reset command is

given.

Set\Reset commands



30/44

What do you think ?

Pressing a key will turn the Output ON. The Output

should stay ON till you press a second (different) key.

Try to turn the Output ON and OFF using just one key

(pressing once will turn it ON and pressing it again will

turn the Output OFF).

Advanced


31/44

Ladder logic

Timers

A Timer is a Coil that you energize, and

after a specified amount of time (Timers

preset) the Timers Contact turns ON(usually).

There are several types of timers:

On delay Timer

Timer accumulatedTimer extended



32/44

Ladder logic

On Delay TimerAccumulated TimerTimer extended


33/44

What do you think ?

Pressing a key will turn an Output ON and OFF in cycles

of 5 seconds. Pressing the key again will stop it.

Pressing a key once will make the Output turn ON for 10

seconds.


34/44

Ladder logic

DataTypes

There are some more data types in the

PLC beside the bits, the Inputs and the

Outputs.

Those data types are called, in general,Registers.

Some of the registers are Integers, some

are Long Integers, and some are Double

Words.


35/44

Ladder logic

What is a Register

MI MLDW

-32768 to 32767-2147483648 to 2147483647

0 to 4294967296

0

1

23

4

5


36/44

Ladder logic

A register is a sum of bits. An Integer

contains 16 bits, a Long Integer contains 32

bits, and the same goes for a DW which

contains 32 bits and is unsigned.

What is a Register

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

V l

Sign


37/44

Ladder logic

The value stored in a register is always binary

but it can be viewed in different ways.

The most common view of a register value is

decimal, but sometimes Hexadecimal is also very

useful.

1 111 110 0 11 1100 00

1x2^0+1x2^1+1x2^2+1x2^3+1x2^4+1x2^5+1x2^6+1x2^7+1x2^8+1x2^9+1x2^10+0x2^11+0

x2^12+0x2^13+0x2^14+0x2^15=1023=3FF

What is a Register


38/44

Ladder logic

What is a register

The value stored in a register can also be a

representation ofASCII characters. In this case,

every character is placed in a byte which is actually

8 bits of data. This is also true when we talk of a

string, which is a sum of registers holding a set ofcharacters.

Characters in a register are read right to left (low

to high).

Mi 1 Mi 2Mi 0

31 34 33 36 3532 123456


39/44

What do you think ?

In what format is the number FF (Binary, Decimal or

Hexadecimal)?

How many bytes are in a MI?

What is the biggest number one can store in a MI?

How many bits are in a MI?


40/44

Ladder logic

Analog Values

The best example for using registers is

when we want to measure analog values in

the PLC.

Analog values are stored in registers and

evaluated according to their resolution.

If we have an analog input that gives10

bit resolution, it means that the value in the

register linked to this input will be in the

range of 0-2^10 or 0-1023 digits.


41/44

Ladder logic

In order to add the analog reading to the

control system, we have functions that can

compare values, do math calculations and

move data (store).

Those functions and more can be linked

to any type of register.

Analog Values


42/44

What do you think ?

Add to this application that the Output will turn ON only if

the value is in range for more than 10 sec.

Lets write a small application that compares the analog

input to Min and Max values (constant set points) and

turns an Output ON when the reading is between them.


43/44

ACE


44/44

ace oplc presentation kurs

Documents