The document discusses programmable logic controllers (PLCs) and their input/output (I/O) sections. PLCs use I/O modules to provide an interface between field devices and the central processing unit. Modular PLCs have external I/O modules that plug into racks near the field devices to minimize wiring. The PLC's memory uses an addressing system to keep track of all input and output information by assigning addresses that indicate each piece of data's location.
Summer Internship Report For PLC Programming of Traffic light through Ladder ...Aman Gupta
For free download Subscribe to https://www.youtube.com/channel/UCTfiZ8qwZ_8_vTjxeCB037w and Follow https://www.instagram.com/fitrit_2405/ then please contact +91-9045839849 over WhatsApp.
An industrial PLCs system is used for the development of the controls of machinery. This paper describes the PLCs systems in terms of their architecture, their interface to the process hardware, the functionality and the application development facilities they provide. Some attention is also paid to the industrial standards to which they abide their planned evolution as well as the potential benefits of their use. Ladder Logic is a graphical programming language, initially programmed with simple contacts that simulates the opening and closing of relays. Ladder Logic programming has been expanded to include functions such as Counters, Timers, shift Registers and math operations. Ladder logic is a method of drawing electrical logic schematics. It is now a graphical language very popular for programming Programmable Logic Controllers (PLCs). It was originally invented to describe logic made from relays. The name is based on the observation that programs in this language resemble ladders, with two vertical "rails" and a series of horizontal "rungs" between them.
Identify elements associated with the preparation of a programmable l.pdfakcopier1
Identify elements associated with the preparation of a programmable logic controller program.
Before starting the development of a programmable logic controller program, there are a number
of important steps which shall be taken into consideration e.g. selection of PLC based on
input/output, etc...identify some other important steps and elements.
Solution
A programmable logic controller, PLC, or programmable controller is a digital computer used
for automation of typically industrialelectromechanical processes, such as control of machinery
on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many machines,
in many industries. PLCs are designed for multiple arrangements of digital and analog inputs and
outputs, extended temperature ranges, immunity to electrical noise, and resistance to vibration
and impact. Programs to control machine operation are typically stored in battery-backed-up or
non-volatile memory. A PLC is an example of a \"hard\" real-time system since output results
must be produced in response to input conditions within a limited time, otherwise unintended
operation will result.
Before the PLC, control, sequencing, and safety interlock logic for manufacturing automobiles
was mainly composed of relays, cam timers,drum sequencers, and dedicated closed-loop
controllers. Since these could number in the hundreds or even thousands, the process for
updating such facilities for the yearly model change-over was very time consuming and
expensive, as electricians needed to individually rewire the relays to change their operational
characteristics.
Digital computers, being general-purpose programmable devices, were soon applied to control of
industrial processes. Early computers required specialist programmers, and stringent operating
environmental control for temperature, cleanliness, and power quality. Using a general-purpose
computer for process control required protecting the computer from the plant floor conditions.
An industrial control computer would have several attributes: it would tolerate the shop-floor
environment, it would support discrete (bit-form) input and output in an easily extensible
manner, it would not require years of training to use, and it would permit its operation to be
monitored. The response time of any computer system must be fast enough to be useful for
control; the required speed varying according to the nature of the process.[1] Since many
industrial processes have timescales easily addressed by millisecond response times, modern
(fast, small, reliable) electronics greatly facilitate building reliable controllers, especially because
performance can be traded off for reliability.
In 1968 GM Hydra-Matic (the automatic transmission division of General Motors) issued a
request for proposals for an electronic replacement for hard-wired relay systems based on a white
paper written by engineer Edward R. Clark. The winning proposal came from Bedford
Associates of Bedford, Massachusetts. T.
In todays world, PLC is heart and brain of all industries no matter which segment it is. It has changed the face of technology and way of work. Hear i am sharing just the basic and the evolution of PLC.
Choosing the right PLC can be overwhelming for most people. If you’ve been tasked with determining what control solution is needed for your next application, a control system integrator (CSI) can be an excellent resource. A CSI should be technology agnostic. Their priority should be to understand your specific technical and commercial requirements.
Choosing the right PLC can be overwhelming for most people. If you’ve been tasked with determining what control solution is needed for your next application, a control system integrator (CSI) can be an excellent resource. A CSI should be technology agnostic. Their priority should be to understand your specific technical and commercial requirements.
Summer Internship Report For PLC Programming of Traffic light through Ladder ...Aman Gupta
For free download Subscribe to https://www.youtube.com/channel/UCTfiZ8qwZ_8_vTjxeCB037w and Follow https://www.instagram.com/fitrit_2405/ then please contact +91-9045839849 over WhatsApp.
An industrial PLCs system is used for the development of the controls of machinery. This paper describes the PLCs systems in terms of their architecture, their interface to the process hardware, the functionality and the application development facilities they provide. Some attention is also paid to the industrial standards to which they abide their planned evolution as well as the potential benefits of their use. Ladder Logic is a graphical programming language, initially programmed with simple contacts that simulates the opening and closing of relays. Ladder Logic programming has been expanded to include functions such as Counters, Timers, shift Registers and math operations. Ladder logic is a method of drawing electrical logic schematics. It is now a graphical language very popular for programming Programmable Logic Controllers (PLCs). It was originally invented to describe logic made from relays. The name is based on the observation that programs in this language resemble ladders, with two vertical "rails" and a series of horizontal "rungs" between them.
Identify elements associated with the preparation of a programmable l.pdfakcopier1
Identify elements associated with the preparation of a programmable logic controller program.
Before starting the development of a programmable logic controller program, there are a number
of important steps which shall be taken into consideration e.g. selection of PLC based on
input/output, etc...identify some other important steps and elements.
Solution
A programmable logic controller, PLC, or programmable controller is a digital computer used
for automation of typically industrialelectromechanical processes, such as control of machinery
on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many machines,
in many industries. PLCs are designed for multiple arrangements of digital and analog inputs and
outputs, extended temperature ranges, immunity to electrical noise, and resistance to vibration
and impact. Programs to control machine operation are typically stored in battery-backed-up or
non-volatile memory. A PLC is an example of a \"hard\" real-time system since output results
must be produced in response to input conditions within a limited time, otherwise unintended
operation will result.
Before the PLC, control, sequencing, and safety interlock logic for manufacturing automobiles
was mainly composed of relays, cam timers,drum sequencers, and dedicated closed-loop
controllers. Since these could number in the hundreds or even thousands, the process for
updating such facilities for the yearly model change-over was very time consuming and
expensive, as electricians needed to individually rewire the relays to change their operational
characteristics.
Digital computers, being general-purpose programmable devices, were soon applied to control of
industrial processes. Early computers required specialist programmers, and stringent operating
environmental control for temperature, cleanliness, and power quality. Using a general-purpose
computer for process control required protecting the computer from the plant floor conditions.
An industrial control computer would have several attributes: it would tolerate the shop-floor
environment, it would support discrete (bit-form) input and output in an easily extensible
manner, it would not require years of training to use, and it would permit its operation to be
monitored. The response time of any computer system must be fast enough to be useful for
control; the required speed varying according to the nature of the process.[1] Since many
industrial processes have timescales easily addressed by millisecond response times, modern
(fast, small, reliable) electronics greatly facilitate building reliable controllers, especially because
performance can be traded off for reliability.
In 1968 GM Hydra-Matic (the automatic transmission division of General Motors) issued a
request for proposals for an electronic replacement for hard-wired relay systems based on a white
paper written by engineer Edward R. Clark. The winning proposal came from Bedford
Associates of Bedford, Massachusetts. T.
In todays world, PLC is heart and brain of all industries no matter which segment it is. It has changed the face of technology and way of work. Hear i am sharing just the basic and the evolution of PLC.
Choosing the right PLC can be overwhelming for most people. If you’ve been tasked with determining what control solution is needed for your next application, a control system integrator (CSI) can be an excellent resource. A CSI should be technology agnostic. Their priority should be to understand your specific technical and commercial requirements.
Choosing the right PLC can be overwhelming for most people. If you’ve been tasked with determining what control solution is needed for your next application, a control system integrator (CSI) can be an excellent resource. A CSI should be technology agnostic. Their priority should be to understand your specific technical and commercial requirements.
Seminar Presentation on Programmeble Logic Controller , By an Engineering Student For doing Professional Presentation like Business Presentation, Industrial Use
Seminar Presentation on Programmeble Logic Controller , By an Engineering Student For doing Professional Presentation like Business Presentation, Industrial automation process,
Implementation of T-Junction Traffic Light Control System Using Simatic S7-20...IJERA Editor
A conventional traffic light control system is designed by using devices such as timers, relays and
contactors etc. The critical timing operation is required to be carried out under the existence of heavy
traffic situations. This conventional practice leads to many problems that need additional maintenance
cost and subsequent delay for a long time. With the help of a PLC, the requirement of fast automation
and effective optimization of traffic light control system can be achieved. Use of PLC helps us to
develop this process not only for traffic signal on the roads, but also on the movement of trains and
the transfer of containers in ports in maritime works. In order to provide a solution to the above
problem, this paper introduces an execution and implementation of T-junction traffic control system
using SEIMENS S7-200 PLC. Programming in PLC is written in ladder logic with the help of STEP7
MICROWIN software
For free download Subscribe to https://www.youtube.com/channel/UCTfiZ8qwZ_8_vTjxeCB037w and Follow https://www.instagram.com/fitrit_2405/ then please contact +91-9045839849 over WhatsApp.
Programmable Logic Controller (PLC) is a specialized computing system used for control of industrial machines and processes.
Seminar Presentation on Programmeble Logic Controller , By an Engineering Student For doing Professional Presentation like Business Presentation, Industrial Use
Seminar Presentation on Programmeble Logic Controller , By an Engineering Student For doing Professional Presentation like Business Presentation, Industrial automation process,
Implementation of T-Junction Traffic Light Control System Using Simatic S7-20...IJERA Editor
A conventional traffic light control system is designed by using devices such as timers, relays and
contactors etc. The critical timing operation is required to be carried out under the existence of heavy
traffic situations. This conventional practice leads to many problems that need additional maintenance
cost and subsequent delay for a long time. With the help of a PLC, the requirement of fast automation
and effective optimization of traffic light control system can be achieved. Use of PLC helps us to
develop this process not only for traffic signal on the roads, but also on the movement of trains and
the transfer of containers in ports in maritime works. In order to provide a solution to the above
problem, this paper introduces an execution and implementation of T-junction traffic control system
using SEIMENS S7-200 PLC. Programming in PLC is written in ladder logic with the help of STEP7
MICROWIN software
For free download Subscribe to https://www.youtube.com/channel/UCTfiZ8qwZ_8_vTjxeCB037w and Follow https://www.instagram.com/fitrit_2405/ then please contact +91-9045839849 over WhatsApp.
Programmable Logic Controller (PLC) is a specialized computing system used for control of industrial machines and processes.
Similar to 6.- Chapter 2 PLC Hardware Components.ppt (20)
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
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Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
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146. The memory structure for a PLC processor
consists of several areas, some of these having
specific roles.
With tag-based memory structures all data are assigned
a variable name called a tag. A program can be
developed using only tag names but you must assign
input and output terminals to input and output tags
before the program can be executed
With rack-based memory structures
addresses are derived using the rack
number, the I/O module slot number
and the screw terminal number where
the I/O device is wired.
147. The memory space can be divided into two
broad categories: program files and Data files.
Program and
Data file
organization for
the SLC 500
controller.
148. Program files are the areas of processor memory
where ladder logic programming is stored.
Program files are the part of
the processor memory that
stores the user ladder logic
program. The program
accounts for most of the total
memory of a given PLC system.
149. The Data file portion of the processor’s memory
stores input and output status, processor status,
the status of various bits, and numerical data.
These files are
organized by
the type of data
they contain.
153. The PLC-5 and SLC 500 store all data in global
data tables and are based on 16-bit operations.
You access these data by specifying the address of
the data you want.
The addresses in the output data file and the input
data file are potential locations for I/O modules
mounted in the chassis.
154. The status data file
contains information about
the processor status
The bit data file stores
bit status and frequently
serves for storage when
using internal outputs.
155. The timer file stores
the timer status and
timer data.
The counter file
stores the counter
status and counter
data.
156. The integer file
stores integer
data values.
The floating point file
can store data that
requires a decimal
point.
157. The input image table
is allocated to storing
the on/off status of
connected discrete
inputs.
If the input is on (switch
closed), its corresponding
bit in the table is set to 1.
If the input is off (switch
open), the corresponding
bit is cleared, or reset to 0.
159. The output image table is
allocated to storing the
on/off status of connected
discrete outputs.
If the program calls for
an output to be ON, its
corresponding bit in the
table is set to 1.
If the program calls for
an output to be OFF, its
corresponding bit in the
table is set to 0.
161. Typically, micro PLCs have a fixed number of
inputs and outputs.
This controller has 20 discrete inputs with addresses I/0 through
I/19 and 12 discrete outputs with addresses O/1 through O/11.
163. During each program scan cycle, the processor
reads all the inputs, takes these values, and
energizes or de-energizes the outputs according to
the user program.
164. The time it takes to complete a scan cycle is a
measure of how fast the controller can react to
changes in inputs.
If a controller has to react to
an input signal that
changes states twice during
the scan time, it is possible
that the PLC will never be
able to detect this change.
165. The scan time is a function of:
• The speed of the processor module
• The length of the ladder program
• The type of instructions executed
• The actual ladder true/false conditions
The PLC computes the scan time each
time the END instruction is executed.
Typical scan time data include the
maximum scan time and the last scan time.
171. PLC programming language refers to the method
by which the user communicates information to
the PLC.
Standard PLC programming languages
172. Ladder diagram language is the most commonly
used PLC language and is designed to mimic
hardwired relay logic.
Hardwired relay
control circuit
Equivalent ladder
diagram program
173. Instruction list programming language consists
of a series of instructions that refer to the basic
AND, OR, and NOT logic gate functions.
Hardwired relay
control circuit
Equivalent instruction
list program
174. Functional block diagram programming uses
instructions that are programmed as blocks wired
together to accomplish certain functions.
175. Ladder diagram and functional block diagram
programming used to produce the same logical
output.
Ladder diagram
Equivalent
function block
diagram.
179. The ladder diagram language is a symbolic set
of instructions used to create the controller
program.
Representations of contacts and coils are the basic
symbols of the logic ladder diagram instruction set.
180. The Examine If Closed (XIC) instruction looks
and operates like a normally open relay contact.
Associated with each XIC
instruction is a memory bit
linked to the status of an
input device or an internal
logical condition in a rung.
181. The memory bit is set to 1 or 0 depending on the
status of the input.
A 1 corresponds to a true status or on condition.
If the instruction memory bit is a 1 (true) this
instruction will allow rung continuity through itself,
like a closed relay contact.
182. A 0 corresponds to a false status or off condition.
If the instruction memory bit is a 0 (false) this
instruction will not allow rung continuity through
itself and will assume a normally open state just like
an open relay contact.
184. The Examine If Open (XIO) instruction looks
and operates like a normally closed relay
contact.
This instruction asks the PLC’s processor to examine
if the contact is open.
It does this by examining the bit at the memory
location specified by the address for a 0 or 1.
185. As with any other input the memory bit is set to 1 or 0
depending on the status of the input. A 1 corresponds to
a true status or on condition.
The instruction is interpreted as false when the bit is
1 and will not allow rung continuity through itself.
186. A 0 corresponds to a off condition.
The instruction is interpreted as true when the bit is
0 and will not allow rung continuity through itself.
188. The Output Energize (OTE) instruction looks and
operates like a relay coil.
This instruction signals the PLC to energize
(switch on) or de-energize (switch off ) the output.
The instruction is associated with a memory bit that
energizes the output when set to 1 and de-energizes
the output when reset to 0.
189. A true logic
path is
established by
the input
instructions in
the rung.
OTE instruction
is set to 1 to
energize the
output.
191. Action of the field device and PLC bit.
A signal
present
makes the
NO bit (1)
true; a signal
absent makes
the NO bit
(0) false. The
reverse is
true for an
NC bit.
193. The main function of the ladder logic diagram
program is to control outputs based on input
conditions.
Each contact or coil symbol is referenced with an
address that identifies what is being evaluated and
what is being controlled.
The same contact
instruction can be
used throughout the
program whenever
that condition needs
to be evaluated.
194. For an output to be activated or energized, at
least one left-to-right true logical path must exist.
A complete closed
path is referred to
as having logical
continuity.
When logical continuity exists in at least one path, the
rung condition and Output Energize instruction are
said to be true.
197. To complete the entry of a relay-type instruction,
you must assign an address to each instruction.
Address indicates
what input is
connected to what
input device
Address indicates
what output is
connected to what
output device
199. The assignment of an I/O address can be
included in the I/O connection diagram.
Inputs and outputs are typically represented by
squares and diamonds, respectively.
201. Branch instructions are used to create parallel
paths of input condition instructions.
The rung will be
true if either
instruction
A or B is true.
203. Parallel branches can be used to allow more than
one combination of input conditions.
Either A and not B, or C provides logical
continuity and energizes output D.
205. Output branching allows a true logic path to
control multiple outputs
Either A or B provides a
true logical path to all
three output instructions:
C, D, and E.
Additional input
instructions can be
programmed in the
output branches.
206. Simulated program, either A or B provides a
true logical path to all three output instructions:
C, D, and E.
207. Input and output branches can be nested to avoid
redundant instructions and to speed up processor
scan time.
A nested branch starts or ends within another branch.
208. In some PLC models, the
programming of a nested
branch cannot be done
directly.
It is possible, however,
to program a logically
equivalent branching
condition.
209. There may be limitations to the number of series
contact instructions that can be included in one
rung of a ladder diagram as well as limitations
to the number of parallel branches.
210. The PLC will not allow
for programming of
vertical contacts.
Reprogrammed to eliminate
vertical contact.
211. The processor examines the ladder logic rung for logic
continuity from left to right.
If programmed as shown,
contact combination
FDBC would be ignored.
Reprogrammed circuit.
213. An internal output does not directly control an
output field device.
The advantage of using internal outputs is that there
are many situations in which an output instruction is
required in a program but no physical connection to a
field device is needed.
215. Internal relay used for a program that requires
more series contacts than the rung allows.
This PLC allows for only 7 series contacts when 12
are actually required for the programmed logic.
218. Examine If Closed (XIC) instruction
Both the NO and the NC pushbuttons are represented
in the program by the Examine If Closed instruction.
The normal state of the field input device (NO
or NC) does not matter to the controller.
What matters is that contacts need to closed to energize
the output.
220. Examine If Open (XIO) instruction
The pushbutton is represented in the user program by
an Examine If Open instruction.
This is because the rung must be true when the
external pushbutton is open and false when the
pushbutton is closed.
225. Allen-Bradley’s RSLogix software
packages are windows
programming packages used to
develop ladder logic programs.
Software, in various versions,
can be used to program the
PLC-5, SLC 500,
ControlLogix, and MicroLogic
family of processors.
A personal computer is most often used and is adapted
to the particular PLC model through the use of the
relevant programmable controller software.
227. Instruction toolbar with bit instructions selected.
To place an instruction on a rung, click its icon on
the toolbar and simply drag the instruction straight
off the toolbar onto the rung of the ladder.
228. The programming software needs to know what
processor is being used in conjunction with the
user program.
The Select Processor Type screen contains a list of the
different processors that the RSLogix software can
program.
229. The I/O Configuration screen lets you double
click or drag-and-drop a module from an all-
inclusive list to assign it to a slot in your
configuration.
230. Data File screens contain data that are used in
conjunction with ladder program instructions
and include input and output files as well as
timer, counter, integer, and bit files.
The bit file B3 is used for internal relays.
231. Relay ladder logic is a graphical programming
language designed to closely represent the
appearance of a wired relay system.
The logic is apparent
from the
highlighting which
identifies the logic
state of contacts in
real time and which
rungs have logic
continuity.
233. A processor has basically two modes of operation:
the program mode and some variation of the run
mode.
A three-position keyswitch may be used to select
different processor modes of operation.
234. The program mode is used to enter
a new program, edit or update an
existing program, upload files and
download files.
The run mode is used to
execute the user program.
The test mode is used to operate
or monitor the user program
without energizing any outputs.
The remote position allows the PLC to be remotely
changed between program and run mode by a
personal computer connected to the PLC processor.