Modul PLC Programming.pdf

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CHAPTER 4 – PROGRAMMING
Main Objective:
Provide an overview of PLC programming method using programming languages commonly
used.
Specific Objectives:
After completed this chapter, student will know the major component
1. Familiarise with the PLC Programming system
2. Able to explain PLC programming method using Ladder Diagram and mnemonic
code., Instruction set and logic function.
3. Understand and use Ladder Diagram and mnemonic code to solve control systems
circuits.
4. Explain the following logic instruction set: Load. Load Not, Out, And, And Not, Or,
Or Not, And Ld and Or Ld.
5. Explain sequential instruction set: No Operation, End, Interlock, Jump, Keep,
Set/Reset and Differential Up/Down.
6. Explain the timer and Counter instruction set and execute timer/counter application
solution methods.
4.0 Introduction
PLC programming process is to plan activities such as design and write a program to perform
the required tasks.
Here are the parts that should be there in a PLC program.
Start Starting an operation
Operating Mode Determining the origin of the device input / output and
also the starting point
The Reset Controlling the operation of start / stop it manually or
automatically in the program
Operations / Ordering
Process
Program design as required by the task
Signal Output Trigger output devices.
Status Output Display indicator light or alarm.
End Stop the process./operation

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4.1 Programming Language
IEC 1131-3 is the international standard for programmable controller programming languages.
The following is a list of programming languages specified by this standard:
i. Ladder Diagram (LD)
ii. Instruction List (IL)
iii. Structured Text (ST)
iv. Sequential Function Chart (SFC)
v. Function Block Diagram (FBD)
One of the primary benefits of the standard is that it allows multiple languages to be used
within the same programmable controller. This allows the program developer to select the
language best suited to each particular task.
i. Ladder Diagram
Ladder Diagram is kind of graphical programming language that changed the relay control
wiring circuit diagram. Ladder Diagram contains tracks from left to right contact diagram (see
Figure below). This platform is connected to contact elements available normally open - NO or
available Normally closed - NC through the current path and loop elements.
Ladder diagram also shows the control circuit and the display function and a combination of
the sequence of operations for each branch of the horizontal lines separately.
Ladder Diagram
Mnemonic Instruction
There are other methods to program PLCs. One of the earliest techniques involved mnemonic
instructions. These instructions can be derived directly from the ladder logic diagrams and
entered into the PLC through a simple programming terminal.
ii. Instruction List
This low-level language is similar to Assembly language and is useful in cases where small
functions are repeated often. Although it is powerful, it is considered to be difficult to learn.
+ve -ve
INPUT CONDITION OUTPUT ACTION
NO NC

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Example
Calculate new weight by subtracting tare weight from net weight.
LD weigh_command
JMPC WEIGH_NOW
ST ENO
RET
WEIGH_NOW: LD gross_weight
SUB tare_weight
iii. Structured Text
Structured Text (ST) is a high level textual language that is a Pascal like language. It is very
flexible and intuitive for writing control algorithms.
Structured Text uses operators such as logical branching, multiple branching, and loops. People
trained in computer programming languages often find it the easiest language to use for
programming control logic. When symbolic addressing is used, ST programs resemble
sentences, making it highly intelligible to beginner users as well.
ST is ideal for tasks requiring complex math, algorithms or decision-making. Its concise format
allows a large algorithm to be displayed on a single.
Benefits of Structured Text
 People trained in computer languages can easily program control logic
 Symbols make the programs easy to understand
 Programs can be created in any text editor
 Runs as fast as ladder
Example 1
We have Motor that will be controlled manually by 2 push buttons (Start Push Button, and Stop Push Button).
When the Start Push Button is pushed then the Motor will be turned ON. and when the Stop Push Button is
Pushed then we want to stop the Motor. (Security logic has been taken off this logic, for the purpose of
domonstration.)
IF StartPb THEN
Motor := 1;
END_IF;
IF StopPb THEN
Motor := 0;
END_IF;

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iv. Sequential Function Chart
These are similar to flowcharts, but much more powerful. This method is much different from
flowcharts because it does not have to follow a single path through the flowchart.
SFC programming offers a graphical method of organizing the program. The three main
components of an SFC are steps, actions and transitions. Steps are merely chunks of logic, i.e., a
unit of programming logic that accomplishes a particular control task. Actions are the individual
aspects of that task. Transitions are the mechanisms used to move from one task to another.
Control logic for each Step, Action and Transition is programmed in one of the other languages
such as Ladder Diagram or Structured Text.
Is a kind of graphic language (see Figure 4.1.4). Elements are the steps, transitions, choice and
parallel branch. Each step shows the status of the control program processes the active or
inactive. One step consists of action based on the transition. The action consists of the
sequence structure itself.
v. Function Block Diagram
Like SFC, FBD is a graphical language that allows programming in other languages (ladder,
instruction list, or structured text) to be nested within the FBD. In FBD, program elements
appear as blocks which are "wired" together in a manner resembling a circuit diagram. FBD is
most useful in those applications involving a high degree of information/data flow between
control components, such as process control.
Step 1 MOTOR (Start)
Step 2
Step 3
MOTOR (Stop)
Transition 1
Transition 2
Action
Sample Program In Sequencial Function Chart Language

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4.1.1 Basic Ladder Diagram
A ladder diagram consists of a vertical line on the left and right are called bus bars and
horizontal lines to the right, called the instruction lines.
Along the lines of command are logical combinations of conditions (conditions) that will
determine when and how the instructions on the right at all to be implemented.
Based on the picture above, one should note that a ladder diagram consists of two basic parts:
left section also called conditional, and a right section which has instructions. When a condition
is fulfilled, instruction is executed.
Example Ladder Diagram as shown in figure below .
instruction
00000 00001
00002
00003 00004
00005 00006
00007
Sample Ladder Diagram
00007
00007

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The pairs of vertical lines along the branch line is called the conditions. These conditions
consist of two, namely:
i. Normally open condition (NO)
ii. Normally closed condition (NC)
The numbers in each case to determine the bit operations per instruction. Each command in
ladder diagram either ON or OFF depending on the status of specified bit operations.
Notes:
Normally open condition is ON if the bit operation is ON and will be OFF if the bit operation is OFF .
Normally closed condition is ON if the bit operation is OFF and will be OFF if bit operation is ON.
4.2 Basic Terms
4.2.1 Execution Conditions
Logical combination of the ON and OFF states gathered to establish an instruction to be
implemented. This condition is called Execution Condition. Refer to figure below.
Instructions will be in the Execution Conditions ON when IR 00000 is ON, IR 00001 is OFF and IR
00002 is ON.
Instruction
n
Instruction
n
00000
Normally Open
Normally Closed
00000
Instruction executed when
the IR bit 00000 is ON
Instruction executed when
the IR bit 00000 is OFF
Example of Ladder Diagram
instruction
00000 00001 00002
Examples of Execution Conditions

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4.2.2 Operand Bits
Bit operations for each instruction can consist of any of the bits in the memory area IR, SR, HR,
TC or TR. This means that the conditions in Ladder Diagram can be determined by the bit I / O,
flags , work bits , timer / counters and others.
Table 4.3.2 shows the memory map refers to the PLC type SYSMAC OMRON-CQM1H.
DATA AREA BIT FUNCTION
Input
Area
IR00000 -
IR01515
Used as the input bit
Output
Area
IR10000 –
IR11515
used as output bits.
IR Area
Work
Area
IR21600 –
IR21915
Bit has no function
specifically. Can be used
freely in the program
SR Area SR24400 –
SR25507
This bit use to do certain
functions, such as flags
(flags) and control bits.
TR Area TR 0 – TR 7 This bit is used to
temporarily store the status
ON / OFF on the branches
of the program
HR Area HR 0000 – HR
9915
This bits used to store data
and maintain the status ON
/ OFF when the power is
off.
Timer/Counter Area TC 000 – TC 511 The same number used for
the timer and counter. Use
for TC000 to TC002.
`interval timer '

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4.2.3 Logic Block
The respond to an instruction is determined by the relationship between the conditions on the
instruction line that connects them. Any group of conditions that formed to produce a logical
result is called a logical block. Refer to Figure 4.3.3.
4.2.4 Instruction Block
A block of instruction is composed of all the instructions contained in a block. Block is obtained
by drawing a horizontal line without cutting a vertical line and vice versa. Refer to Figure 4.3.3.
4.2.5 Mnemonic Code
Ladder diagram can not be read by the Programming Console. Thus the ladder diagram should
be changed to mnemonic code. Mnemonic code provides the same information as ladder
diagram and can be typed directly on Programming Console.
ADDRESS INSTRUCTION OPERASI / DATA
00000 LD 00000
00001 OR 00001
00002 AND 00003
00003 AND LD
00004 OUT 10000
00005 TIM 000
#0050
00006 CNT 002
#0010
00007 FUN 01
instruction
00000 00002
0000
1
0000
3
Example Logic Block
Example Mnemonic Code

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ANSWER ALL THESE QUESTIONS
1. What do you understand about Ladder Diagram and draw one (1) example of a Ladder
Diagram.
2. Explain the purpose of the following terms:
i. The logic blocks
ii. The Instruction block
Reference;
1. http://www.kronotech.com/ST/st.htm

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UNIT 5: BASIC INSTRUCTIONS SET
OBJECTIVE:
Describe the set of instructions used in PLC programming
SPECIFIC OBJECTIVES:
At the end of this unit student should be able to:
i. Know the functions of the instruction LOAD, LOAD NOT, OUT, AND, AND NOT,
OR, NOT and OR END
ii. Know the function block instruction AND LD and OR LD.
iii. Convert Ladder diagram to Mnemonic Code.
NOTE: These instructions will be explained later is based on OMRON PLC brands –
SYSMAC CQM1H
5.0 Introduction
There are a lot of instructions used to develop the PLC program. Each instruction has a
respective function.
5.1 LD - LOAD Instruction
These instructions are use to start a line of the program.
It is used in the first contacts in the normally open condition (NO).
Ladder Diagram Mnemonic Code
Explanation:
The Execution Conditions of the instruction on the right will be ON when IR 00000 is ON.
instruction
00000 Address Instruction Operand/Data
00000 LD 00000
00001 instruction

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5.2 LD NOT - LOAD NOT Instruction
These instructions are use to start a line of the program.
It is used in the first contacts in the normally closed condition (NC).
Explanation
The Execution Conditions of the instruction on the right will be ON when IR 00000 is OFF
5.3 AND - AND Instruction
These instructions are used in the second contact in a normally open (NO) and a
series with previous contacts
Explanation
The Execution Conditions of the instruction on the right will be ON when IR 00000 and IR 00001
are ON
instruction
n
00000 LD NOT 00000
00001 instruction
instruction
n
00000 00001 Address Instruction Operand/Data
00000 LD 00000
00001 AND 00001
00002 instruction

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5.4 AND NOT - AND NOT Instruction
These instructions are used in the second contact in a normally closed (NC) and in
series with previous contacts
Explanation
The Execution Conditions of the instruction on the right will be ON when IR 00000 ON and IR
00001 are OFF.
5.5 OR - OR Instruction
These instructions are used in the second contact in a normally open (NO) and in
line (parallel) with previous contacts.
.
Explanation
The Execution Conditions of the instruction on the right will be ON when either IR 00000 or
IR 00001 are ON.
instruction
n
00000 00001 Address Instruction Operand/
Data
00000 LD 00000
00001 AND NOT 00001
00002 instruction
instruction
n
00000
Address Instruction Operand/Data
00000 LD 00000
00001 OR 00001
00002 instruction
00001

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5.6 OR NOT - OR NOT Instruction
These instructions are used in the second contact in a normally closed (NC) and in
line (parallel) with previous contacts
Explanation
The Execution Conditions of the instruction on the right will be ON when either IR 00000 is ON
or IR 00001 is OFF or IR 00000 ON, IR 00001 OFF simultaneously
5.7 OUT - OUTPUT Instruction
These instructions are used for the coil output.
 IR 10000 will ON when IR 00000 is ON .
5.8 END
 END instruction has no physical contact device.
 It is the last instruction required for completion of a program.
 If no END instruction, the program cannot be implemented
instruction
n
00000 LD 00000
00001 OR NOT 00001
00002 instruction
0000
1
00000 Address Instruction Operand/
Data
00000 LD 00000
00001 OUT 10000
10000

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 For PLC type OMRON - SYSMAC CQM1H, the instruction FUN 01 is the END instruction.
5.9 OR LD - BLOCK LOGIC OR Instruction
 The OR LD instruction has no physical contact device.
 Only a programming tool for solving complex OR function as a series of contacts LD (or
LD NOT), in parallel with a series of other contacts.
END
00000 00001 Address Instruction Operand/
Data
00000 LD 00000
00001 AND NOT 00001
00002 OUT 10000
00003 FUN 01
1000
0
END
00000 00001 Address Instruction Operand/Data
00000 LD 00000
00001 AND 00001
00002 LD 00002
00003 AND 00003
00004 OR LD
00005 OUT 10000
00006 FUN 01
1000
0
00002 00003

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5.10 AND LD - BLOCK LOGIC AND Instruction
 The AND LD no physical contact device.
 Only a programming tool for solving complex functions such as AND connects a
number of OR, OR NOT, OR LD in the series.
00001
5.11 OR LD and AND LD
When both logic block instruction is to be used in Ladder Diagram, a program must be
written from the bottom up to merge logic blocks. For example, ladder diagram below:
Logic block of instruction for the last two blocks (blocks b1 and b2 blocks) are written
first and then followed by the first logic block instruction (block a).
END
00000
00001
Address Instruction Operand/
Data
00000 LD 00000
00001 OR 00002
00002 LD 00001
00003 OR 00003
00004 AND LD
00005 OUT 10000
00006 FUN 01
10000
00002 00003

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Ladder Diagram
Mnemonic Code
Example.
END
00000 00001
1000
0
00002 00003
00000 LD NOT 00000
00001 AND 00001
00002 LD 00002
00003 AND NOT 00003
00004 LD NOT 00004
00005 AND 00005
00006 OR LD
00007 AND LD
00008 OUT 10000
00009 FUN 01
00004 00005
Block a Block b2
Block b1
Block b2
Block a
Block b1
Block b2 + Block b1 = Block b
Block b, Block a

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UNIT 6 (4.3) : SEQUENTIAL INSTRUCTION SET
Objective
Describe the sequence instruction set NO OPERATION, END, INTERLOCK, JUMP, KEEP, SET /
RESET and DIFFERENTIATE UP / DOWN
Specific Objectives:
At the end of this unit you should be able to understand set of instructions the following
sequence:
 NO OPERATION
 END
 INTERLOCK
 JUMP
 KEEP
 SET/RESET
 DIFFERENTIATE UP / DOWN
6.0 Introduction
In this unit you will be exposed to a sequence of instructions which usually acts as the last
instruction in the instruction line.
Instruction sequence SET, RESET, KEEP, DIFFERENTIATE UP, DOWN DIFFERENTIATE, used to
ON and OFF state output bits in the IR. These instructions are used to control the status of the
other bits in the IR or in other areas.
INTERLOCK instruction sequences can overcome the problem of storing execution conditions,
in the branches of the ladder diagram.
JUMP instruction sequence can be used to control devices that require a product that can last a
long time.
6.1 NO OPERATION – NOP ( 00 )
 These instructions do not have a ladder diagram symbols and will not do any operations.
 When you remove the memory in this instruction will be displayed on the console screen PLC
programming.

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6.2 END – END(01)
 Acting as the last instruction for each program (see figure 6.2)
 There is no instruction will be written after the END instruction (01) implemented.
 If there is no END instruction (01) in the program, the task would not be implemented
and verse NO END LIST is displayed on the programming PLC console screen.
Ladder Diagram shows the END instruction
Mnemonic Code
6.3 INTERLOCK [ IL ( 02 ) ] DAN INTERLOCK CLEAR [ ILC ( 03 ) ]
 IL (02) and ILC (03) must be used together.
 These instructions are used to solve the problem of storing execution conditions at
branch points.
 When the INTERLOCK instruction is ON as shown in Ladder Diagram 6.3, the
implementation of the INTERLOCK instruction will control all of the instruction
execution until the instruction ‘INTERLOCK CLEAR’. When the INTERLOCK instruction is
OFF, INTERLOCK CLEAR instruction will reset the program operation.
 To set the INTERLOCK instruction for PLC tpe OMRON - SYSMAC CQM1H is FUN 02 for
INTERLOCK instruction and FUN 03 is INTERLOCK CLEAR instruction.
00000
END
10000
Address Instruction
Operand/Data
00000 LD NOT 00000
00001 OUT 10000
00002 FUN(01)

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00000
00001 10000
Mnemonic Code
Address Instruction
Operand/Data
00000 LD 00000
00001 FUN 02 -
00002 LD 00001
00003 OUT 10000
00004 FUN 03 -
00005 FUN 01 -
Referring to Ladder Diagram 6.3,
 When the instruction input LD 00 000 is ON, the instruction IL (02) will be ON.
 Instruction output OUT 10 000 will depend on the instruction input ON LD 00001 and LD
00000.
 If the input instruction LD 00 001 ON, output OUT 10000 will be ON.
 If the input instruction LD 00 001 OFF, output OUT 10000 will be OFF.
 In the event that the input instructions LD 00 000 OFF, instruction IL (02) is OFF.
 Instructions to the output OUT 10 000 will be OFF.
 Next program ILC (03) will reset the program.
IL (02)
ILC (03)
END
Figure 6.3 : Ladder Diagram shows IL ( 02 ) dan ILC ( 03 )
instruction

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 Refer the table below:
Instructions
LD 00000
IL(02)
Instructions
LD 00001
Input
Instructions
OUT 10000
Output
ON ON
ON
OFF OFF
ON OFF
OFF
OFF OFF
6.4 JUMP [ JMP (04) ] DAN JUMP END [ JME (05) ]
 Instructions JMP (04) is usually used in pairs with the command JME (05) for the jump.
 JMP (04) is a command to determine the starting point of the jump and JME (05) is the
instruction that the direction of the jump.( where to jump).
 When the instruction JMP (04) is ON, no jump will occur and the program will be
implemented as written.
 When the instruction JMP (04) is OFF, a jump to the instruction JME (05) which has the
same number will be done. Further instructions are the instructions JME (05) will be
implemented.
 Instructions JUMP and JUMP END can use the numbers from the range of 00 to 99.
 To set the instruction for PLC type OMRON - SYSMAC CQM1H, is FUN 04 for JUMP
instruction and FUN 05 instruction is the JUMP END instruction.
00000
00001 10000
JMP (04)
01
JME (05) 01
END
Figure 6.4 : Ladder Diagram shows JUMP instruction

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Mnemonic Code
Address Instruction
Operand/Data
00000 LD 00000
00001 FUN (04) 01
00002 LD 00001
00003 OUT 10000
00004 FUN (05) 01
00005 FUN (01) -
• When the input instruction LD 00000 is ON, instruction JMP (04) will be ON.
Subsequent instructions will be implemented as written.
If the input instruction LD 00 001 is ON, output instruction OUT 10000 will be ON.
If the input instruction LD 00 001 is OFF, output instruction OUT 10000 will be OFF.
• When the input instruction LD 00 000 is OFF, instruction JMP (04) will be OFF. Next
jumps to Instruction JME (05) will occur. All instruction that is between JMP (04) and JME
(05) will be ignored.
• Refer to the table below.
Instruction LD 00000
JMP(04)
Input
Instruction OUT 10000
Output
ON ON
ON
OFF OFF
OFF Not implemented/executed Not implemented/executed

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6.5 KEEP – KEEP (11)
 KEEP instruction is used to maintain the status bit operation based on two state
execution condition.
 KEEP (11) operates like a Latching Relay which is set by S and reset by R.
 When S is in the ON state, the operation of a particular product instruction is ON
and remain ON until reset, regardless of whether S is ON or OFF.
 When R is in the ON state, the operation of a particular product instruction is OFF
and remain OFF until reset, regardless of whether R is ON or OFF.
 For PLC type OMRON - SYSMAC CQM1H, the instruction FUN 11 is KEEP instruction.
00002
00003
Mnemonic Code
Address Instruction Operand / Data
00000 LD 00002
00001 LD 00003
00002 FUN (11) HR 0000
00003 LD HR 0000
00004 OUT 10004
00005 FUN (01)
Figure 6.5 : Ladder Diagram shows KEEP instruction
HR0000
KEEP (11)
HR 0000
S
R
END
10004

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With reference to Figure 6.5,
 Instruction LD 00 002 acts as S (Set)-and the LD 00 003 acts as R (Reset).
 When the instruction LD 00 002 ON, the output instruction OUT 10004 will be ON and
will remain ON even if the instruction LD 00 002 is OFF.
 When the instruction LD 00 003 ON, then the output OUT 10004 instruction OFF and
will remain OFF even though the instruction LD 00 002 in OFF or ON state.
Reset
Set
Instruction OUT 10004
Output
ON ON
OFF
OFF ON
ON OFF
ON
OFF OFF
6.6 SET and RESET
 SET and RESET instruction will change the status of bit operations only when the
implementation is ON.
 In the OFF condition, the instructions will not change the bit operation status.
00000
00001
Figure 6.6 : Ladder Diagram shows the Set and Reset instruction
SET 10000
RESET 10000

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Mnemonic Code
00000 LD 00000
00001 SET 10000
00002 LD 00001
00003 RESET 10000
 When the input instruction LD 00 000 is ON, SET instruction command to ON and always
ON regardless of whether the input instruction LD 00 000 is ON or OFF.
 When the inputs instruction LD 00 001 is ON, RESET instruction is ON and SET
instruction will be off .
 Its operations can be understood clearly in the KEEP instruction.
6.7 DIFFERENTIATE UP [ DIFU (13) ] DAN DIFFERENTIATE DOWN [DIFD (14) ]
 DIFU instructions (13) and DIFD (14) will ON the output within a very short time.
 Instructions DIFU (13) will turn the output to ON when the input signal changes from
OFF to ON.
 Instructions DIFD (14) will turn the output to ON when the input signal changes from
ON to OFF.
 For PLC type of OMRON - SYSMAC CQM1H, instruction FUN 13 is instruction
DIFFERENTIATE UP and FUN 14 is instruction DIFFERENTIATE DOWN.
Input
DIF U
DIF D

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00000
Figure 6.7a : Ladder Diagram shows DIFFERENTIATE UP instruction
Mnemonic Code
00000 LD 00000
00001 FUN (13) 01000
00002 LD 01000
00003 OUT 10000
Referring to Ladder Diagram 6.7a,
 When the input instruction LD 00000 is ON (has changes from OFF to ON), operand bit
01 000 will be ON, the output OUT 10000 will be ON within a very short time and then
OFF. We can not see the situation in the products.
 After that the operand bit 01 000 will be OFF regardless of the status of the input
instruction LD 00 000.
00000
Figure 6.7b : Ladder Diagram shows the DIFFERENTIATE DOWN instruction
DIFU (13)
01OOO
END
01000
10000
DIFU (14)
01OOO
END
01000
10000

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Mnemonic Code
00000 LD 00000
00001 FUN (14) 01000
00002 LD 01000
00003 OUT 10000
Referring to Ladder Diagram 6.7b,
 When the input instruction LD 00 000 is OFF (change from ON to OFF), operand bit
01000 will be ON, the output OUT 10000 will be ON within a very short time and then
OFF. We can not see the situation in the products.
 After that the operand bit 01000 will be OFF regardless of the status of the input
instruction LD 00 000.

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UNIT 7(4.4) : TIMER AND COUNTER
OBJECTIVE:
Describe the instruction set of timer and counter.
SPECIFIC OBJECTIVES:
At the end of this unit you should be able to:
1. Describe the instruction timer (TIMER – TIM)
2. Describe the instruction counter (COUNTER - CNT).
3. Converts Ladder Diagram to mnemonic code.
7.0 Instruction
TIMER (TIM) and COUNTER (CNT) is the instructions that require numbers TIM / CNT (N) and
the set value(SV). The range of numbers TIM / CNT is from 000 to 511, while the range of set
values for the TIM / CNT is 0000 to 9999
The numbers TIM / CNT can not be used twice. When a number has been used as definer, such
as number 000 for instructions on TIM / CNT, the number can not be used again.
When a number is defined as the number of TIM / CNT, it can be used as often as required as
an operator operand in other instructions from the command TIMER or COUNTER.
7.1 TIMER - TIM
Symbol
 Timer numbers (N) is between 000 and 015.
 The set value (SV) is between 0000 to 9999.
 All numbers TIM / CNT can be used as definer in only one TIMER or COUNTER
instruction.
TIM N
SV
SV

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Example 7.1.1
 TIMER is enabled/activated when the execution condition is ON and will be reset to set
value (SV) when the execution condition is OFF.
 The set value (SV) of TIMER is the BCD between # 0000 to # 9999. For example, if TIMER
be set to 5 seconds, then the set value (SV) is # 0050.
Ladder Diagram
Mnemonic Code
00000 LD 00000
00001 TIM 000
# 0050
00002 LD TIM 000
00003 OUT 10000
00004 FUN 01
Operating Condition:
When the input (LD 00000) is ON, the timer contact will be activated after 5 seconds. Next the
output (OUT 10000) will be ON
END
00000
TIM 000 10000
Tim 000
# 0050
(5 saat)

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Example 7.1.2
Ladder Diagram
TIM 000 10001
Mnemonic Code
00000 LD 00000
00001 TIM 000
# 0050
00002 LD TIM 000
00003 OUT 10000
00004 LD NOT TIM 000
00005 OUT 10001
00006 FUN 01
When the input (LD 00000) ON, the timer (TIM 000) will be activated after 5 seconds and the
output (OUT 10000) will be ON. While the output (OUT 10 001) will be ON as soon as the supply
is supplied and will be OFF after 5 seconds. Timer will continue to be active as long as the input
00000 state is ON.
END
00000
TIM 000 10000
Tim 000
#0050
(5 saat)

PLC PROGRAMMING
SARIATI Page 30
Example 7.1.3
Ladder Diagram
Mnemonic Code
00000 LD 00000
00001 TIM 000
# 0050
00002 LD TIM 000
00003 AND NOT TIM 001
00004 OUT 10000
00005 LD 10000
00006 TIM 001
#0030
00007 OUT 10001
00008 FUN 01
00000
TIM 000 10000
Tim 000
# 0050
(5 saat)
Tim 001
# 0030
(3 saat)
TIM 001
10000
END

PLC PROGRAMMING
SARIATI Page 31
When the input (LD 00000) ON, the timer (TIM 000) will be activated after 5 seconds. Next the
output (OUT 10000) will be ON.
After 3 seconds the output (OUT 10000) ON, the timer (TIM 001) will be activated the next
output (OUT 10000) will be OFF and the timer (TIM 001) will be OFF.
When the timer TM001 OFF, contact TIM 001 (NC) will be ON and the output (OUT 10000) is
ON state.
Output (OUT 10000) will continue ON and OFF until the input (LD 00000) in the OFF state.
7.2 COUNTER - CNT
Symbol
 Number TIM / CNT can be used as definer for either timer or counter.
 Counter numbers are range from 000 to 015.
 Counters are used to calculate the count down from the set value (SV) on the
execution condition on the counting pulse (CP) when it is changed from OFF to ON.
 The set value (SV) is range 0000 to 9999.
 Counters will reset to the reset (R).
Ladder Diagram
CP
R
CNT
N
SV
CP
R
CNT 001
# 0010
(10 kiraan)
END
0000
0
00001
CNT 001
10000

PLC PROGRAMMING
SARIATI Page 32
Mnemonic Code
00000 LD 00000
00001 LD 00001
00002 CNT 000
#0010
00003 LD CNT 001
00004 OUT 10000
00005 FUN 01
Operating Condition
Counter set to count 10. When the input (LD 00,000) is the pulse of ten, a counter will be
activated and thus the output (OUT 10000) will be ON. When reset (LD 00,001) ON, a counter
will be in original condition

PLC PROGRAMMING
SARIATI Page 33
7.3 The Application Of Timer And Counter Instructions
The number of Counter cannot be the same number to the number of timer because both
share the same data in the PLC memory.
R
Counter set to count 5. When the input (LD 00,000) is the pulse of five, a counter will be
activated and thus the output (OUT 10000) will be ON.
When the output (OUT 10000) ON, TIM 001 will be activated after 3 seconds and then the
output (OUT 10 001) will be ON.
Both the output (OUT 10000) and (OUT 10 001) will always be ON until reset (LD 00001) in the
ON state.
Reset will return the counter to its original condition.
CNT 000
# 0005
(5
kiraan)
CP
0000
0
0000
1
TIM 001
# 0050
( 5 saat )
END
CNT 000 10000
1000
0
TIM 001 10001

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Modul PLC Programming.pdf