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ControlLogix PLC Systems Training Manual
INTECH Process Automation Inc. 1
Allen Bradley ControlLogix
Training Manual
INTECH Process Automation Nigeria (Ltd.)
50 Herbert Macauley Street Old G.R.A., Port Harcourt, Nigeria.
3. CONNECTING A COMPUTER TO NETWORK .............................................. 14
3.1 MANAGE PROJECT FILES .................................................................................... 16 3.1.1 Save your Changes ........................................................................................ 18
3.2 ORGANIZE TASKS .............................................................................................. 19 3.2.1 Organize your Logic ..................................................................................... 19
3.4.5 Creating a periodic task ................................................................................ 28 3.5 PROGRAM .......................................................................................................... 29
3.5.1 Creating a Program ....................................................................................... 29
3.6 ROUTINE ............................................................................................................ 31 3.6.1 Creating a Routine ........................................................................................ 31 3.6.2 Main Routine ................................................................................................ 32
3.7 DATA ORGANIZATION ........................................................................................ 34 3.7.1 Properties of a tag ......................................................................................... 34 3.7.2 Naming Tags ................................................................................................. 34 3.7.3 Types of tags ................................................................................................. 35
3.7.4 Data Types .................................................................................................... 35 3.7.5 Creating Tags ................................................................................................ 36 3.7.6 Alias Tags ..................................................................................................... 37
4.5.1 Loss of communication ................................................................................. 47
4.5.2 Configure a Major Fault to Occur ................................................................. 47 4.5.3 Monitor the Health of a Module ................................................................... 48
4.6 ADDRESS I/O DATA ........................................................................................... 50 4.6.1 Add 1756 I/O at Runtime .............................................................................. 52
4.7 DETERMINE WHEN DATA IS UPDATED .............................................................. 52 4.8 RECONFIGURE AN I/O MODULE ......................................................................... 54
4.8.1 Reconfigure a module via RSLogix 5000 software ...................................... 54
4.9 DATA STRUCTURES ............................................................................................ 55 4.9.1 Predefined structures ..................................................................................... 55
5. COMMUNICATION WITH CONTROLLER .................................................... 60
5.1 DRIVER CONFIGURATION IN RSLINX ................................................................. 60 5.2 CONFIGURE PATH TO TARGET CONTROLLER IN RSLOGIX5000 ......................... 65
6. HOW TO MODIFY PROGRAM ONLINE ......................................................... 66
6.1 HOW TO ADD A NEW RUNG IN THE ONLINE PROGRAM ...................................... 66 6.2 HOW TO EDIT A RUNG IN THE ONLINE PROGRAM .............................................. 73
7. HOW TO MONITOR A TAG IN THE ONLINE PROGRAM ......................... 75
7.1 END OF SESSION EXERCISES: ............................................................................. 77
8. HOW TO FORCE ANY I/O IN ONLINE PROGRAM ...................................... 79
9. HOW TO PRINT INFO FROM THE PROGRAM ............................................ 83
9.1 HOW TO PRINT CONTROLLER PROPERTIES ......................................................... 83 9.2 HOW TO PRINT ROUTINE LOGIC ......................................................................... 84 9.3 HOW TO PRINT USER DEFINE DATA TYPES ........................................................ 85 9.4 HOW TO PRINT TAGS ......................................................................................... 86
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10. GET SYSTEM VALUE (GSV) & SET SYSTEM VALUE (SSV)
12.1.1 Precaution for I/O Chassis ...................................................................... 102 12.2 CONTROLLOGIX POWER SUPPLY ..................................................................... 102
12.2.1 Precaution for Power Supply .................................................................. 103 12.2.2 Troubleshooting the Power Supply ......................................................... 105
12.4.1 Precaution for ControlLogix Controller Battery ..................................... 110
12.4.2 Troubleshooting the ControlLogix Controller Battery ........................... 112 12.5 CONTROLLOGIX DIGITAL INPUT MODULE ....................................................... 114
12.5.1 Interpreting Status Indicator ................................................................... 115 12.5.2 Troubleshooting the Digital Input Module ............................................. 115
12.6 CONTROLLOGIX DIGITAL OUTPUT MODULE ................................................... 117 12.6.1 Interpreting Status Indicator ................................................................... 118
12.6.2 Troubleshooting the Digital Output Module........................................... 118 12.7 CONTROLLOGIX ANALOG INPUT MODULE ...................................................... 120
12.7.1 Troubleshooting the Analog Input Module............................................. 121
12.8 CONTROLLOGIX ANALOG OUTPUT MODULE ................................................... 122 12.8.1 Troubleshooting the Analog Output Module .......................................... 123
12.9 TROUBLESHOOTING REMOTE IO PROBLEM ...................................................... 124
13. DEVELOPING A PROJECT AND TROUBLESHOOTING ...................... 136
13.1 IO POINTS TO BE USED IN THE PROJECT ........................................................... 136 13.2 STARTING UP ................................................................................................... 136 13.3 TAG NAME CONVENTION ................................................................................. 136 13.4 PROGRAMMING ROUTINE ................................................................................. 136
13.5 MAPPING HARDWARE IO’S TO CONTROLLER TAG ........................................... 136
Figure 1: ControlLogix System ........................................................................................ 11 Figure 2: ControlLogix System Overview ........................................................................ 12 Figure 3: Local Area Connection ...................................................................................... 14 Figure 4: Local Area Connection Properties .................................................................... 15
Figure 5: Internet Protocol (TCP/IP) Properties ............................................................... 15 Figure 6: New Controller .................................................................................................. 16 Figure 7: Name of the Controller ...................................................................................... 17 Figure 8: Task Folder ........................................................................................................ 20
Figure 9: Control Properties.............................................................................................. 22 Figure 10: Control Property Window ............................................................................... 23
Figure 11: Control Application ......................................................................................... 25 Figure 12: Tasks, Programs and Routines ........................................................................ 26
Figure 13: Execution order ............................................................................................... 27 Figure 14: New Task ......................................................................................................... 28 Figure 15: New Task Window .......................................................................................... 28
Figure 16: Main Task ........................................................................................................ 29 Figure 17: New Program Window .................................................................................... 30
Figure 18: Creating a Routine ........................................................................................... 31 Figure 19: New Routine Window ..................................................................................... 32 Figure 20: Program Properties .......................................................................................... 33
Figure 48: Add new rung .................................................................................................. 66 Figure 49: Add new rung (Continued) .............................................................................. 67 Figure 50: Add new rung (Continued) .............................................................................. 67 Figure 51: Add new instruction ........................................................................................ 68
Figure 52: Tag Browser .................................................................................................... 68 Figure 53: Tag Selected from Tag Browser ...................................................................... 69
Figure 54: Tag Browser for Output element ..................................................................... 69 Figure 55: Tag Selected from Tag Browser ...................................................................... 70
Figure 56: Accept pending Edits....................................................................................... 70 Figure 57: Finalize all Edits in the Program ..................................................................... 71 Figure 58: Finalize all Edits in the Program (Continued) ................................................. 71
Figure 99: IO Chassis Grounding ................................................................................... 102 Figure 100: Power Supply mounted on a ControlLogix Chassis .................................... 102 Figure 101: Earth Ground Protection for Power Supply ................................................ 103
Figure 102: Screwing Power Supply in the Chassis ....................................................... 104 Figure 103: Troubleshooting the Power Supply ............................................................. 105
Figure 104: ControlLogix Controller .............................................................................. 107 Figure 105: Installation of Controller in the Chassis ...................................................... 108 Figure 106: Controller LED’s ......................................................................................... 108
Table 16: Controller BAT LED Indicator ...................................................................... 110 Table 17: Batteries Replacement Date ........................................................................... 112
Table 18: Worst-case Estimates of Battery Life ............................................................. 113 Table 19: DC Input Module Status Indicators Description ............................................ 116 Table 20: DC Output Module Status Indicators Description.......................................... 119
Table 21: Analog Input Module Status Indicators Description ...................................... 121
Table 22: Analog Output Module Status Indicators Description ................................... 123 Table 23: Ethernet Module Status Indicators Description .............................................. 126 Table 24: Ethernet Module Status Indicators Description (Continued) ......................... 127
Table 25: ControlNet Module Status Indicators Description ......................................... 131 Table 26: ControlNet Module Status Indicators & Display Diagnostics ....................... 135
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MODULE 1
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1. Introduction This course provides students with the necessary resources and hands-on practice to efficiently
troubleshoot a ControlLogix. It builds upon the student’s fundamental knowledge of common
controller terms and operation, the student’s ability to identify and create fundamental
RSLogix 5000 project components and the student’s experience interpreting basic ladder logic.
This course adds to the student’s skill set by introducing new tasks such as connecting to a
network, interpreting project execution, editing ladder logic, and more.
After practicing such skills, students will be presented with a systematic strategy for diagnosing
and troubleshooting a variety of system errors, for example, software configuration, electrical
noise, controller, I/O, and other possible problems.
2. ControlLogix System Overview The ControlLogix system provides sequential, process, motion, and drive control together with
communication and I/O in a chassis-based system. A simple ControlLogix system consists of a
stand-alone controller and I/O modules in a single chassis as shown in the figure.
Figure 1: ControlLogix System
For a more flexible system, use:
Multiple controllers in a single chassis.
Multiple controllers joined across networks.
I/O from multiple platforms that is distributed in many locations
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Figure 2: ControlLogix System Overview
ControlLogix system includes:
ControlLogix Controllers
ControlLogix Communication Modules
ControlLogix I/O Modules
ControlLogix Power Supplies
ControlLogix Chassis
Optional system components include:
Operator Interface and Computers
Software
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2.1 ControlLogix Controller
ControlLogix controller provides a variety of controller solution that is capable of addressing a large amount of I/O points. Controller can be placed into any slot of a ControlLogix I/O chassis
and multiple controllers can be installed in the same chassis. Multiple controllers in the same
chassis communicate with each other over the backplane but operate independently.
2.2 ControlLogix Communication Modules
Different communication modules are available for different networks (i.e. ControlNet, Ethernet,
DeviceNet etc.).
2.3 ControlLogix Power Supplies
Power supplies are used with 1756 chassis to provide power to the chassis backplane. These
power supplies provide all voltages necessary for any ControlLogix module to operate in the
chassis.
2.4 ControlLogix Chassis
The ControlLogix system is a modular system that requires a 1756 I/O chassis. Standard chassis
are available in sizes of 4, 7, 10, 13, and 17 module slots. Any card can be place in any slot. The
backplane provides a high-speed communication path between modules.
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3. Connecting a Computer to Network
1. Make sure that NIC (Network Interface Card) card is installed in the computer.
2. Connect one end of the Ethernet cable to the NIC of the computer and other end to the
Ethernet switch of the network.
3. Go to Start and click on the control panel icon.
4. Double click on the Network Connections icon.
5. Double click on the Local Area Connection icon the following window will open.
Figure 3: Local Area Connection
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6. Click on the properties Tab and select Internet protocol (TCP\IP) as shown in the figure.
Figure 4: Local Area Connection Properties
7. Click on the Properties Tab and select “Use the following IP address” radio button as
shown in the figure
Figure 5: Internet Protocol (TCP/IP) Properties
8. Asked IP address from your Network Administrator. Enter IP address in the “IP address”
field and click OK.
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9. In order to verify that your computer is connected to network “ping” other systems on the
network by using command prompt. If you receive response from systems on the network
it means that your computer is successfully connected to the network.
3.1 Manage Project Files
Before you program a Logix5000 controller, you must create a project File:
1. Start the RSLogix 5000™ software.
2. From the File menu, select New.
8 7 6 5 4 3
.
Figure 6: New Controller
3. Select the type of controller.
4. Type a name for the controller.
5. Type a description of the operations that the controller performs (Optional).
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6. Select the type of chassis (number of slots) that contains the controller.
7. Select or type the slot number where the controller is installed
8. To store the file in a different folder (other than the default Create In path), click
Browse and select a folder.
9. Click OK.
When you create a project, the name of the project file is the same as the name of the controller.
Figure 7: Name of the Controller
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3.1.1 Save your Changes
As you create logic and make configuration changes, save the project.
To: Do this:
save your changes From the File menu, select Save.
make a copy of the open
project A. From the File menu, select Save As.
but keep the existing
name of B. Type a name for the project file. Use
the controller Underscores [ _ ]in place of spaces.
C. Click Save.
make a copy of the
project and A. From the File menu, select Save As.
assign a different name to
the controller
B. Type a name for the project file. Use
Underscores [_] in place of spaces.
C. Click Save.
D. In the controller organizer, right-click
Controller name_of_controller Folder and
select Properties.
E. Type a new name for the controller.
F. Click OK.
Table 1: Saving Changes
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3.2 Organize Tasks
After you create a project file, organize your project into tasks. To organize your project into
tasks, do the following steps:
Identify the Available Programming Languages
Organize Your Logic
Verify the Controller
3.2.1 Organize your Logic
To execute your logic, you use a task (s). There are two types of Tasks:
This type of task: Will:
continuous task Continuously execute your logic (You can only
have one Continuous task.)
periodic task · interrupt the continuous task
· execute logic one time
· return control to the continuous task
(You can have more than one periodic
task.)
Table 2: Tasks of a controller
The Tasks folder contains the tasks for the controller (i.e., your logic).
Main Task is the default continuous task. It runs all the time and repeatedly executes Main
Program. Whenever Main Program executes, any logic in Main Routine will execute. You can
use Main Routine to call other routines (subroutines) within Main Program.
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Figure 8: Task Folder
If you execute: Then: Detailed steps:
a function at a constant rate
(e.g., execute a PID loop
every 100 ms)
1.Create a Periodic Task A. In the controller organizer,
Right-click Tasks and select New
Task.
B. Type:
name_of_task
description (optional)
C. From the Type list, select
Periodic.
D. Under Periodic Attributes, type:
rate
priority
E. Click Ok
2.Create a Program for
the Task
A. Right-click name_of_task and
select New
B. Type:
name_of_program
description (optional)
C. Click OK.
3. Create and assign a A. Click the + sign that is next to
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Main Routine (The
routine to execute first in
the Program)
name_of_task.
B. Right-click name_of_program
and select
Routine.
C. Type:
name_of_main_routine
description (optional)
D. From the Type drop-down list,
select the Programming language for
the routine.
E. Click OK.
F. Right-click name_of_program
and select Properties.
G. Click the Configuration tab.
H. From the Main drop-down list,
select
name_of_main_routine
I. Click OK.
J. To add additional routines
(subroutines) To the program repeat
steps B. to E
Table 3: Tasks for the Controller
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3.2.2 Verify the Controller
As you program your project, periodically verify your work:
1. In the top-most toolbar of the RSLogix 5000 window, clicks verify.
2. If any errors are listed at the bottom of the window:
To go to the first error or warning, press the F4 key.
Correct the error according to the description in the Results Window.
Go to step 1.
3. To close the Results window, press the Alt + 1 key.
3.3 Project Properties
To view the Controller Properties:
1. Place the cursor over the Controller folder.
2. Click the right mouse button and select Properties.
Figure 9: Control Properties
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3. The controller property window is shown (as shown below).
Figure 10: Control Property Window
3.3.1 Tabs description
General: modify the controller name, description, and controller properties for the current
project.
Date/Time: online only view and edit the controller’s wall clock time and the coordinated system
time status.
Communications: configure communication information that is stored with the project file.
Serial Port: view and configure the serial port on the controller.
Serial Port Protocol: configures the serial port for:
DF1 point-to-point
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DF1 slave
DF1 master
Major Faults: online only view any major faults that have occurred on the controller.
Minor Faults: online only view any minor faults that have occurred on the controller.
Advanced: some features are online only view and edit advanced controller properties, which
include the system fault program, the power loss program, and system overhead time slice
File view: information about the project file.
3.3.2 Project organization
The controller operating system is a preemptive multitasking system that is IEC-1131-3
compliant. This environment provides:
Tasks to configure controller execution.
Programs to group data and logic.
Routines to encapsulate executable code written in a single programming language.
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Figure 11: Control Application
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3.4 Tasks, programs and routines
3.4.1 Definitions
Figure 12: Tasks, Programs and Routines
3.4.2 Task
A task provides scheduling and priority information for a set of one or more programs that
execute based on specific criteria. Once a task is triggered (activated), all the programs assigned
(scheduled) to the task execute in the order in which they are displayed in the controller
organizer. Tasks can be continuous or periodic.
Tasks can be scheduled, edited, and controlled. Each task can contain multiple programs, status
information, and configuration information.
The Logix5550 controller supports 32 separate tasks. One task, the Main Task, is always
continuous; the other 31 tasks are periodic. When you create a project, the Main Task is already
defined as a continuous task.
Once you create a task, there are other properties that you must configure, such as how the
programs within the task execute. You can prioritize the tasks up to 15 levels:
the continuous task has the lowest priority
a task at a higher priority (i.e., lower priority number) pre-empts one at a lower priority
(i.e., higher priority number)
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Tasks at the same priority execute on a time-slice basis at 1 ms intervals .Once you create
a task; you can later change its descriptive information if you wish.
3.4.3 Continuous Task
The continuous task runs in the background. Any CPU time not allocated to other operations
(such as motion, communications, and periodic tasks) is used to execute the programs within the
continuous task.
The continuous task runs all the time. When the continuous task completes a full scan, it
restarts immediately.
A project does not require a continuous task. If used, there can be only one continuous
task.
3.4.4 Periodic Task
A periodic task performs a function at a specific rate. Whenever the time for the periodic task
expires, the task interrupts the continuous task, executes one time, and then returns control to
where the continuous task left off. You can configure the time period from 1 ms to 2000 s. The
default is 10 ms. You can create up to 32 periodic tasks and assign a priority to each:
The highest priority task interrupts all lower priority tasks. A higher priority task can interrupt a
lower priority task multiple times. Tasks at the same priority execute on a time-slice basis at 1 ms
intervals. There are 15 configurable priority levels for periodic tasks, from 1 to 15, with 1 being
the highest and 15 being the lowest priority
Example:
Task execution order for a project with two periodic tasks and one continuous task
Figure 13: Execution order
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3.4.5 Creating a periodic task
To create a periodic task:
1. In the controller organizer, right-click the Tasks folder and choose New Task.
Figure 14: New Task
Figure 15: New Task Window
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2. In the Name text box, type a name for the task.
3. From the Type list, choose Periodic (default).
4. In the Watchdog list, type the watchdog time for the task.
5. In the Rate text box, type the rate at which you want the task to execute.
6. In the Priority text box, type the priority for the task.
7. Choose OK
3.5 Program
A program is a subdivision of a task. When a task is triggered, the scheduled programs within the
task execute to completion from first to last.
Each program contains a local data area (referred to as program tags), main executable routine,
subroutines, and a fault routine. The controller supports up to 32 programs. The programs within
a task execute from first to last.
When you create a project, the Main Program is already defined in the Main Task.
Once you create a program, you must then configure the main routine and, optionally, a fault
routine. You can later change the program’s descriptive information if you wish.
3.5.1 Creating a Program
Each task requires at least one program. You can create multiple programs for a task.
1. In the controller organizer, right-click the task that will execute the program and choose
New Program.
Figure 16: Main Task
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2. In the Name text box, type a name for the program.
Figure 17: New Program Window
3. Choose OK
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3.6 Routine
Routines provide the executable code for the project in a controller (similar to a program file in a
PLC or SLC controller). Each routine uses a specific programming language, such as ladder
logic.
Each program must have a main routine configured. You can also specify fault routine and
additional subroutines. You can have as many routines per program as the controller memory
allows.
When you create a project, the Main Routine is already defined in the Main Program.
Once you create a routine, you can later change its descriptive information.
3.6.1 Creating a Routine
Each program requires at least one routine. Use a routine to execute your logic.
To create a routine:
1. In the controller organizer, right-click the program that will execute the routine and
choose New Routine.
Figure 18: Creating a Routine
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Figure 19: New Routine Window
2. In the Name text box, type a name for the routine.
3. From the Type list, choose the programming language for the routine
4. Choose OK
3.6.2 Main Routine
When a program executes, its main routine executes first. Use the main routine to call (execute)
other routines (subroutines). To call another routine within the program, use a Jump to Subroutine
(JSR) instruction.
Each program requires a main routine. The main routine executes whenever the program
executes.
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To define the Main Routine:
1. In the controller organizer, right-click the program that will execute the routine and
choose Properties.
Figure 20: Program Properties
2. Click the Configuration tab.
3. From the Main list, choose the name of the routine.
4. Choose OK
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3.7 Data organization
Logix5000 controllers store data in tags (in contrast to fixed data files that are numerically
addressed). With tags, you can
Organize your data to mirror your machinery
Document (through tag names) your application as you develop it
The controller stores tags as you create them and as they fit into the controller memory. There are
not pre-defined data tables, such as in PLC controllers. Tags of similar data types are not
necessarily grouped together in memory. To group data, use arrays.
The minimum allocation unit within the controller is four bytes.
3.7.1 Properties of a tag
A tag has the following properties:
Scope: defines which routines can access the data
Name: identifies the data (Tags with different scopes can have the same name.)
Data type: defines the organization of the data, such a bit, integer, or floating-point number
3.7.2 Naming Tags
Tag names follow IEC-1131-3 identifier rules:
Name must begin with an alphabetic character or an underscore
Must contain only alphabetic, numeric characters and underscores
Can have as many as 40 characters
Tag names are not case sensitive
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3.7.3 Types of tags
There are three types of tags:
Base A base tag is a tag that actually defines the memory where a data element is
stored. It stores one value at a time.
Alias An alias tag is a tag that references memory defined by another tag. An alias
tag can refer to a base tag or another alias tag.
Alias tags are useful for creating standardized programs that can be duplicated
without having to readdress instructions. By using alias tags, each copy of the
program can reference different base tags.
Consumed A consumed tag is a tag whose data value comes from another controller.
Table 4: Types of Tags
3.7.4 Data Types
Data type Description Range
BOOL 1-bit Boolean 0 = off
1 = on
SINT 1-byte integer -128 to 127
INT 2-byte integer -32,768 to 32,767
DINT 4-byte integer -2,147,483,648 to 2,147,483,647
REAL 4-byte floating-point
number
-3.402823E38 to -1.1754944E38 (negative values)
and
0
and
Table 5: Data Types
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3.7.5 Creating Tags
1. From the Logic menu, select Edit Tags.
2
3 4 5
Figure 21: Creating Tags
2. Select a scope for the tag (Controller tags or Programs tags)
3. Type a name for the tag.
4. Type the data type:
5. Type a description (optional).
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3.7.6 Alias Tags
A tag alias lets you create one tag that represents another tag. This is useful for defining
simplified tag names for elements of structures or arrays.
To define an alias:
1. Select the tag name in tag editor.
2. Right-click on the tag name.
Figure 22: Defining Alias
3. Define the tag.
4. Click Alias.
Figure 23: New Tag Window
5. Choose OK
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MODULE 2
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4. Communication With I/O This chapter provides basic information on how a Logix5000 controller communicates with I/O
modules.
4.1 Configure an I/O Module
To communicate with an I/O module in your system, you add the module to the I/O
Configuration folder of the controller.
Add I/O modules here
Figure 24: Configuring I/O Module
When you add the module, you also define a specific configuration for the Module. While the
configuration options vary from module to module, there are some common options that you
typically configure:
Requested Packet Interval
Communication Format
Electronic Keying
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The Logix5000 controller uses connections to transmit I/O data.
Term: Definition:
Connection
A communication link between two devices, such as between a controller and an I/O module,
Panel View terminal, or another controller.
Connections are allocations of resources that provide more reliable communications between
devices than Unconnected messages. The number of connections that a single controller can
have is limited.
You indirectly determine the number of connections the controller uses by configuring the
controller to communicate with other devices in the system. The following types of
communication use connections
• I/O modules
• Produced and consumed tags
• Certain types of Message (MSG) instructions (not all types use a connection)
Requested
Packet
Interval (RPI)
The RPI specifies the period at which data updates over a connection. For example, an input
module sends data to a controller at the RPI that you assign to the module.
• Typically, you configure an RPI in milliseconds (ms). The range is 0.2 ms (200
microseconds) to 750 ms.
• If a Control Net network connects the devices, the RPI reserves a slot in the stream of data
flowing across the ControlNet network. The timing of this slot may not coincide with the
exact value of the RPI, but the Control system guarantees that the data transfers at least as
often as the RPI.
Table 6: Request Packet Interval
In Logix5000 controllers, I/O values update at a period that you configure via the I/O
configuration folder of the project. The values update asynchronous to the execution of logic. At
the specified interval, the controller updates a value independently from the execution of logic.
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4.1.1 Requested packet interval (RPI)
Take care to ensure that data memory contains the appropriate values throughout a task’s
execution. You can duplicate or buffer data at the beginning of the scan to provide reference
values for your logic.
Programs within a task access input and output data directly from controller-scoped
memory.
Logic within any task can modify controller-scoped data.
Data and I/O values are asynchronous and can change during the course of a task’s
execution.
An input value referenced at the beginning of a task’s execution can be different when
referenced later.
To prevent an input value from changing during a scan, copy the value to another tag and
use the data from there (buffer the values).
4.2 Communication Format
The communication format that you choose determines the data structure for the tags that are
associated with the module. Many I/O modules support different formats. Each format uses a
different data structure. The communication format that you choose also determines:
Direct or Rack-Optimized Connection
Ownership
4.2.1 Direct or Rack-Optimized Connection
The Logix5000 controller uses connections to transmit I/O data. These connections can be direct
connections or rack-optimized connections.
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4.2.2 Direct connection
A direct connection is a real-time, data transfer link between the controller and an I/O module.
The controller maintains and monitors the connection with the I/O module. Any break in the
connection, such as a module fault or the removal of a module while under power, sets fault bits
in the data area associated with the module
A direct connection is any connection
that does not use the Rack Optimization
Comm. Format
Figure 25: New Module Window
4.2.3 Rack-optimized connection
For digital I/O modules, you can select rack-optimized communication. A rack-optimized
connection consolidates connection usage between the controller and all the digital I/O modules
in the chassis (or DIN rail). Rather than having individual, direct connections for each I/O
module, there is one connection for the entire chassis (or DIN rail).
Rack-optimized connection
Figure 26: Rack-Optimized Connection
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4.3 Ownership
In a Logix5000 system, modules multicast data. This means that multiple devices can receive the
same data at the same time from a single device. When you choose a communication format, you
have to choose whether to establish an owner or listen-only relationship with the module.
4.3.1 Owner controller
The controller that creates the primary configuration and communication connection to a module.
The owner controller writes configuration data and can establish a connection to the module.
An owner connection is any connection that does not include Listen-Only in its Comm. Format.
Figure 27: Owner Connection Window
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4.3.2 Listen-only connection
An I/O connection where another controller owns/provides the configuration data for the I/O
module. A controller using a listen-only connection only monitors the module. It does not write
configuration data and can only maintain a connection to the I/O module when the owner
controller is actively controlling the I/O module.
Listen-only connection
Figure 28: Listen Only Connection
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4.4 Electronic Keying
Table 7: Electronic keying
. And another
controller:
And you want to: Then use this type of
connection:
input module does not own
the module
owner (i.e., not listen-only)
owns the
module
maintain communication
with the module if it loses
communication with the
other controller
owner (i.e., not listen-only)
Use the same configuration
as the other owner
controller.
stop communication with
the module if it loses
communication with the
other controller
listen-only
output
module
does not own the module owner (i.e., not listen-only)
owns the module listen-only
There is a noted difference in controlling input modules versus controlling
output modules.
Controlling: This
ownership:
Description:
input modules owner An input module is configured by a controller that
establishes a connection as an owner. This configuring
controller is the first controller to establish an owner
connection.
Once an input module has been configured (and owned by a
controller), other controllers can establish owner
connections to that module. This allows additional owners
to continue to receive multicast data if the original owner
controller breaks its connection to the module. All other
additional owners must have the identical configuration data
and identical communications format that the original
owner controller has, otherwise the connection attempt is
rejected.
listen-only
Once an input module has been configured (and owned by a
controller), other controllers can establish a listen-only
connection to that module. These controllers can receive
multicast data while another controller owns the module. If
all owner controllers break their connections to the input
module, all controllers with listen-only connections no
longer receive multicast data.
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Table 8: Electronic keying (Continued)
Be careful when you disable electronic keying. If used incorrectly, this option can lead to
personal injury or death, property damage, or economic loss.
When you configure a module, you specify the slot number for the module. However, it is
possible to place a different module in that slot, either on purpose or accidently. Electronic keying
lets you protect your system against the accidental placement of the wrong module in a slot. The
keying option you choose determines how closely any module in a slot must match the
configuration for that slot.
If: Then select:
all information must match: Exact Match
type
catalog number
vendor
major and minor revision
number
all information except the minor
revision number
Compatible Module
no information must match Disable Keying
Table 9: Electronic Keying Configuration
output
modules
owner An output module is configured by a controller that
establishes a connection as an owner. Only one owner
connection is allowed for an output module. If another
controller attempts to establish an owner connection, the
connection attempt is rejected.
listen-only Once an output module has been configured (and owned by
one controller), other controllers can establish listen-only
connections to that module. These controllers can receive
multicast data while another controller owns the module. If
the owner controller breaks its connection to the output
module, all controllers with listen-only connections no
longer receive multicast data.
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4.5 Manage a Connection Failure
Outputs respond to the last, non-faulted state of the controlling inputs. To avoid potential injury
and damage to machinery, make sure this does not create unsafe operation. Configure critical I/O
modules to generate a controller major fault when they lose their connections to the controller.
Or, monitor the status of I/O modules.
If the controller loses communication with a module, data from that device does not update.
When this occurs, the logic makes decisions on data that may or may not be correct.
4.5.1 Loss of communication
Controller B requires data from controller A. If communication fails between the controllers, then
controller B continues to act on the last data that it received from controller A.
If communication with a device in the I/O configuration of the controller does not occur for 100
ms, the communication times out. If this occurs, you have these options:
If you want the controller to: Then:
fault (major fault) Configure a Major Fault to occur
continue operating Monitor the Health of a Module
Table 10: Loss of Connection
4.5.2 Configure a Major Fault to Occur
You can configure modules to generate a major fault in the controller if they lose their connection
with the controller. This interrupts the execution of logic and executes the Controller Fault
Handler. If the Controller Fault Handler does not clear the fault, then the controller shuts down.
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If the connection times out, produce a major
fault in the controller.
Figure 29: Configuring a Major Fault To Occur
4.5.3 Monitor the Health of a Module
If you do not configure the major fault to occur, you should monitor the module status. If a
module loses its connection to the controller, outputs go to their configured faulted state. The
controller and other I/O modules continue to operate based on old data from the module.
Figure 30: Health Monitoring Window
If the connection times out, continue operation without invoking a major fault on the controller.
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If communication with a module times out, the controller produces these warnings:
The I/O LED on the front of the controller flashes green.
A shows over the I/O configuration folder and over the device (s) that has timed out.
A module fault code is produced, which you can access through:
Module Properties window for the module
GSV instruction
To monitor the health of your connections, use a Get System Value (GSV) instruction to monitor
the MODULE object for either the controller or a specific module:
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4.6 Address I/O Data
I/O information is presented as a set of tags.
Each tag uses a structure of data. The structure depends on the specific features of the I/O
module.
The name of the tags is based on the location of the I/O module in the system.
When you add a module to the I/O
Configuration folder…
…the software automatically creates Controller-scoped tags for the module.
Figure 31: Addressing I/O Data
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An I/O address follows this format:
Location :Slot :Type .Member .SubMember .Bit
Refer the below table for detailed description
Table 11: I/O Address Details
Where: Is:
Location Network location
LOCAL = same chassis or DIN rail as the controller
ADAPTER_NAME= identifies remote communication adapter or bridge module
Slot Slot number of I/O module in its chassis or DIN rail
Type
Type of data
I = input
O = output
C = configuration
S = status
Member
Specific data from the I/O module; depends on what type of data the module can store.
• For a digital module, a Data member usually stores the input or output bit values.
• For an analog module, a Channel member (CH#) usually stores the data for a channel.
Sub Member Specific data related to a Member.
Bit Specific point on a digital I/O module; depends on the size of the I/O module (0-31 for a 32-
point module)
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4.6.1 Add 1756 I/O at Runtime
With RSLogix 5000 programming software, version 15, you can add 1756 I/O modules to the
Controller Organizer at runtime:
You can only add 1756 I/O modules at runtime
You can add the 1756 I/O modules to the local chassis, remotely via the unscheduled
portion of a Control Net network, and remotely via an Ethernet/IP network.
4.7 Determine When Data Is Updated
ControlLogix controllers update date asynchronous with the execution of logic. Use the following
flowchart to determine when a producer (controller, input module, or bridge module) will send
data.
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Figure 32: Data Flowchart
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4.8 Reconfigure an I/O Module
If an I/O module supports reconfiguration, you can reconfigure the module via:
Module Properties dialog in RSLogix 5000 software
MSG instruction in program logic
Use care when changing the configuration of an I/O module. You could inadvertently cause the
I/O module to operate incorrectly.
4.8.1 Reconfigure a module via RSLogix 5000 software
To change the configuration of an I/O module via RSLogix 5000 software, highlight the module
in the I/O Configuration tree. Right-click and select Properties.
Figure 33: Reconfigure an I/O Module
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4.9 Data Structures
Data structures allow storing a group of data. Each member can be a different data type. Each I/O
module has its own predefined structure. User can create specialized user defined structures using
any combination of predefined data type and other structures. Structures can be created, edited
and deleted in offline mode. Memory allocation depends on the data types for each member
within the structure. Each member is allocated memory to start on an appropriate byte, INT or
DINT. This makes a more efficient use of memory.
4.9.1 Predefined structures
AXIS: control structure for an axis
CONTROL: control structure for array (file) instructions
COUNTER: control structure for counter instructions
MESSAGE: control structure for the MSG instruction
MOTION_GROUP: control structure for a motion group
MOTION_INSTRUCTION: control structure for motion instructions
PID: control structure for the PID instruction
TIMER: control structure for timer instructions
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4.9.2 Creating structures
1. Select Data Types.
2. Click the right mouse button and select New Data Type.
Figure 34: Creating Structure
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3. Description: Enter the description of the structure (optional).
For each member of the structure
Name: Enter the name of the member.
Data Type: Select the data type. The programming software displays a list of the
available data types. The list consists of the predefined data types and any user-defined
data types.
Style: Select the display style of the member. The programming software displays a list
of the available styles, which depends on the data type.
Figure 35: Data Type Window
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4.9.3 Arrays
Arrays let you group a set of data (of the same data type) by the same name and to use subscripts
to identify individual elements. An array can have as many as three dimensions.
Table 12: Arrays
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4.9.4 Indirect Addressing
If the user wants an instruction to access different elements in an array, can use a tag in the
subscript of the array (an indirect address). By changing the value of the tag, you change the
element of the array that your logic references.
Mathematical expressions can be used to specify the subscript of an array.
Figure 36: Indirect Addressing
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5. Communication with Controller This section of manual will be used to connect to a ControlLogix Controller. Following are the
steps involved,
Driver Configuration in RSLinx
Configuring path to the ControlLogix Controller in RSLogix5000
5.1 Driver Configuration in RSLinx
1. Launch RSLinx from the Rockwell Software’s
Figure 37: Launch RSLinx from the Rockwell Software’s
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2. Click on the Communication on the menu bar and select Configure drivers.
Figure 38: Launch RSLinx from the Rockwell Software
There are two communication protocols available for communicating with the ControlLogix
Controller.
Serial (RS232)
Ethernet
For connecting with the controller through its serial port select the RS232 DF1 devices in the
driver drop down list as shown in the figure
Figure 39: RSLinx Serial Driver Configuration
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3. Click add new button, the following window will open
Figure 40: RSLinx Serial Driver Configuration (Continued)
4. Give any name to the driver and press OK.
Figure 41: RSLinx Serial Driver Configuration (Continued)
5. Keeps the default setting. Click on auto configure button and press OK.
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For connecting with the controller through Ethernet select the Ethernet devices in the driver drop
down list as shown in the figure
Figure 42: RSLinx Ethernet Driver Configuration
6. Click add new button, the following window will open