Monday, June 3, 2019
The programming and document
The schedule and document1. IntroductionThe main intention of the assignment is to carry out the schedule and document the mechanisation of a Bytronic associated with Industrial Control Trainer using an Allen-Bradley Micrologix 1000 PLC. It includesAnalysing the mechanical dodge, sensors and actuators.Establishing the check over requirements.High-level design of the PLC program using the sequential Function map (Grafcet) notation.Implementation of the program in ladder logical system form using RSLogix 500 softw be.Program testing.Critical assessment of the completed program adjacent to the decl atomic number 18d requirements.Programmable Logic Controller (PLC)Programmable Logic Controller (PLC) is a programmable electronic blind that is use in the industrial automation systems in order to examine the system commentarys and responses the behaviour of program to manage the outfit devices establish upon the sequence and logic provided to the system.Approximately in all manuf acturing line, electronics and electrical shops and as salutary as in some type of the mechanicals this work on is greatly enhanced. PLC is mainly used in industries and machineries. For general purpose, the PLC is mainly intentional for the multiple commentarys and responses the arrangements of output. entirely in real-time PLC, the output must be produced within a restricted time for the given input conditions.The main benefits of the PLC atomic number 18Communication possibilities.Flexibilities.ReliabilityRealization of complex take care algorithms.System is real simple.Special devices are available.The main functionality of the PLC is to include sequential pass along dictation, statistical discipline that deals with the algorithms and mechanism for controlling the output of a process and distributed control systems.History Of PLCsIn the need of the Ameri raise automotive manufacturing industry, the PLC was invented. initially the programmable comptrollers were adopted by the automated industry. When production models changed, the software revision has been replaced by re-wiring hard-wired control panel. The first programmable logic controllers were designed and developed by Modicon as a pass re-placer for GM and Landis.Later the PLCs were designed to replace the relay logic systems later on that the PLC were programmed in ladder logic which strongly resembles in relay logic. Modern PLC, in Variety ways the programmed can be altered from ladder logic to more traditional phrases like C and BASIC. While reducing the cabinet space that housed the logic, the new system severely increased the functionality of the controls. The first PLC, model 084, was invented by Dick Morley in 1969. The first commercial successful PLC, the 184, was introduced in 1973 and was designed by Michael Greenberg.Interior Structure Of PLCProgrammable Logic Controller is a microcentral processing unit based device that mainly consists of CPU, I/O devices and memory. Addit ionally it is withal connected to the program reader, memory building block and programming and printer.Perform housekeeping activities like communications done RS-232, upcountry diagnostics etc.Perform the control instructions contained in the users programs. This program is stored in ROM/EPROM which is non-volatile memory (data/program cannot be deep in thought(p) when the power has lost).Communicate with some other devices like I/O devices, nedeucerk, programming devices.The main difference between the PLCs and other microprocessor based devices arePLCs are designed rough for the industrial check offtings and secured for improving the electric noise immunity and they are modular.2. System DescriptionProgrammable Logic Controller (PLC) is a programmable device that hub too some manufacturing industries processes. The internal structure of the PLC is similar to many parts of the systems and embedded controllers. The PLC depends upon the types of systems i.e. small, medium a nd overlarge and depending on that the component of the system is built in the distributed unit. The microprocessor based unit is equipment used for controlling and tracking the manufacturing processes. The main advantage of the PLC is easy to design and modify the control process and also the programming languages were adopted.Microprocessor is the main part of the PLC which acts as a vice-versa in the systems. The commands and the instructions from the users program depend on the microprocessor to results system. PLC consists of microprocessor, memory integrated unit and it also consists of retention and reclaim the data from the memory unit. The PLC also includes the communication looks, so that it can transfer the data from system to the PLC and to other terminal devices. In real-time world, it has a capability to control the processes. The main rank of the processor is to examine the number of inputs and results the responses from the system.RAM is a Random Access Memory wh ich is a volatile memory (i.e. when the power has lost the data leave be lost). This type of RAM is not used in the system and it may causes some battery back up in slot. The CMOSRAM (Complementary Metal Oxide semiconductor RAM) is used for storage memory and ladder logic plat.EEPROM (Electrically Erasable Programmable Read Only Memory) is also a non-volatile memory and this type of memory is used for the storage of large amount of data. The other electric devices are used for the storage of small amount of data. It is used to back up the major program in the CMOSRAM processor.ROM (Read Only Memory) is also a non- volatile memory. It can only read the program and the program cannot be modified. It is mainly used to distribute microcode and it does not require an external power supply.Input ModuleThere are several types of input devices to be taken such as pushbuttons, sky shiftinges and some other devices etc. And some other DC inputs devices like electronic card access, thumbp rint, etc are used for the application to access the input module. But in most of the industrial sector system are provided with the essential noisy and electric isolation between the processor and the module.In majority of industrial systems, the processor for the input module takes from 8 to 32 input bits. For each and e very(prenominal) input bit the address will be allocated according to the processor instructions.Output ModuleThe output module can be used for both the device (AC or DC) such as solenoids, relays, contractors and LED readouts. The result depends upon the input module to which the connection has been made through the ports or terminals. The connection towards the input and output devices may vary according to the power supply as well as load. For an analog device, the special type of output device is used to convert from a digital to analog. Whereas for the digital, the special type of output device is used to convert from analog to digital. For analog output devi ce, the results are stored in 12 bit file and convert it to analog signal. The signal may vary from 0 to -10v for DC.CommunicationsThe most commonly used for communication port is RS-232 9-pin connector. In PLC, RS-232 is an in built communication protocol to communicate within the peripheral interfaces and other terminal devices. In todays world, the wide range of communication link in some of the PLC is RS-485 which can access more speed.For peer to peer communication, the larger I/O devices are used in PLC program. There are different methods to communicate between a PLC and a programmer or even with two different PLC. In PLC, the application programs are written in personal computer and downloaded to the system (PC) using the plug in cable to the programming port of the PLC. This communication can be forwarded through the RS-232 or RS-485. The communication between two PLC can be conceded by the keen links supplied through the RS-232. exploit Of PLCThe operation of the all PLCs is followed in four steps continuously takes place in rotationally. The four basic steps followed by the PLC areInput glanceProgram scan Output scan housekeep.The below figure shows the operation of the PLC1) Input Scan It detects all the soil of inputs that are connected to the PLC.2) Program Scan Examine the program logic created by the user to execute.3) Output Scan All the output devices that are connected to the PLC can be energizes or de-energizes.4) Housekeeping This step is used to communicate with the peripherals, programming terminals and other devices etc.PLC Diagram DescriptionIn PLC the programs are fabricated based upon the gates simultaneously with the inputs, timers, sideboards, outputs, internal memory bits, analog inputs, comparators, analog output etc.Inputs The physical connections that are connected to the PLC are switches, pushbuttons, sensors and anything which acts like a switch or signal to the distinguish of ON and off-key position. The voltages that a ccept to some of the devices are 24V DC and some may not it may vary.The switch when it is in ON terra firma, consequently perspective of the device bit is 1 and when it goes to eat up state the status of the device bit is 0.Output The result that appears from the input devices is the communication between the PLC and other terminals. They are used to control the solenoids, sensors, and connectors etc to on and off position.In the PLC, in that respect are 8 sensors and 5 actuators were used. The result from each sensor response the actuators and other sensors to perpetrate the task. These eight sensors has different task they are1) Sensor1 It detects the presence of tholepin in the pep pill sort theatre of operations.2) Sensor2 It detects the components in front of the solenoid at the upper sort area of the ring chute.3) Sensor3 It detects the presence of ring in assembly area.4) Sensor4 It is used to commence assembling.5) Sensor5 It is used to terminate the assembling.6) Sensor6 It is used to detect the complete assemblies.7) Sensor7 It is used to detect the components at the lower sort area.8) Sensor8 It is used to detect the components and assemblies near the reject area solenoid.The purpose of 5 actuator which are used in PLC area are1) Actuator1 It drives the upper chain conveyor motor.2) Actuator2 It drives the lower chain conveyor motor.3) Actuator3 It knocks the ring in the ring chute.4) Actuator4 It releases the ring into the assembly area.5) Actuator5 It rejects the unassembled components.Relay A relay is a switch which is operated on the electromagnetic.Counters when a pre-assigned count value is reached, the digital counters are in the form of relay contact.Timers Timer consists of internal clock, a count value immortalise and an accumulator which is used to count the time.3. RequirementsThe requirements for the PLC diagram areLadder diagramStructure text programmingInstruction listFunctional block programmingSequential functional chart. Requirements ConstraintsDuring the operation, Conveyor belts should be kept moving.When sensor 1 senses it, the actuator 3 should knock only the ring.Overloading of sound should be collected in the profusion rings box.The ring should not enter the peg chute or vice versa.The peg chute and the ring chute should be kept reasonably for the peg and the ring to slide in to that.By the actuator 5, Unassembled components should be knocked downConstraintsActuator should not knock the ring when there are more than 5 rings in the chute if there are more rings 5 rings thus the progress will be blocked.The area between the actuator 4 and the sensor 3 should be clear for the next peg to occupy the space.Only if the peg moves past the ring the assembly will be over.If there are more than 5 rings in the ring chute, the actuator 3 cannot knock.4. Program DesignThe graphical representation of the logic essential in relay logic is a ladder diagram. The ladder diagram instruction consists of rela ys, timers and counters, program control, data transfer, arithmetic operation and data manipulations.In order to create programmable controller program, the ladder diagram language is used. The control logic can be obtained by reducing the ladder instructions symbols. The main objective of the ladder diagram is to control the outputs based on the input circumstances.Based on the simple logic, the ladder rungs can be reduced and also the controlling rungs are based on the logic. The ladder instructions consist of some symbols to perform the program. The symbols to be used in the programming and instruction striation are basic relay type contacts and coil symbols. The representation of the coil symbol is used at the output and whereas the representation of the contact symbol is used at the conditions in orders to control the output. For each and every contact and coil, an address number will be referred.Function Block ProgrammingIn this function block, the instruction for the program ming is very complex for the users program such as data transfer, shift register instruction and so on. And these are also basic building blocks for the control systems.Sequential Function Chart There are some steps to follow the sequential function chart program symbols, they areStart blockInitial blockStep blockTransitionOR pathAND pathThere are three basic standard rules to be followed by the chart1) The first step is to active the program at the toss off block and the programming have an option of restarting the device.2) After the completion of the steps one by one, the transition state will be tested and the action will be continued until the transition is in true state.3) Once the transition is in true state, the processor scans the steps once again to rearrange all timer instructions and executes the next step.The processor scans starts the sequential function chart from left hand to right side and if chart is encountered then it examines the ladder logic from left side to right side.Grafcet is a graphical function chart programming language. This language was adopted by telemechanique into the programmable control language and this language is used for the sequence behaviour of the program. Each step represents the state of system to be controlled and the horizontal terminate represents the conditions to perform the accomplishment.6. Explanation Of ProgramStage10000If fall1 (B31/1) is set to ON state and input sensor 4 is ON (I0/18) but the input sensor 5 (I0/19) is set to OFF state then LATCH (Enable) the rowlock2 and UNLATCH the flag1.0001If flag 2 (B31/2) is set to ON state then change both the output actuator 1 which is a lower conveyor motor (o0/3) and the output actuator 2 which is a upper conveyor motor (o0/4).0002If flag 2 is ENABLE and the input sensor 5 (I0/19) is set to ON state then LATCH the flag1 and UNLATCH the flag 2.Stage 20003If flag 3 (B32/1) is set to ON state and the input sensor 2 (I0/1) is ON state and input sensor 1 (I0/4 ) is set to OFF state and the counter C5 is less than five then LATCH the flag 4 (B32/2) and UNLATCH the flag 3 (B32/1).0004If the flag 4 (B32/2) is set to ON state then enables the timer 1 to 0.01 and preset value to 50 and ENABLES the output actuator 3 (o0/0).0005If the flag 4 is set to ON state and the timer 1 is decrementing then UNLATCH the flag 4 and LATCH the flag 5 (B32/3).0006If the flag 5 (B32/3) is set to ON state and then set the timer 2 (T41) to 0.01 second and preset value to 20 seconds.0007If the flag 5 is set to ON state and the timer 2 (T41) is enable and then LATCH the flag 6 and UNLATCH the flag 5.0008If the flag 6 (B32/4) is set to ON state and then set the counter to up C50 and preset value to 5.0009If the flag 6 is set to ON state and counter up is enabled then LATCH flag 3 and UNLATCH flag 6.Stage 30010If the flag 7 (B33/1) is set to ON state and the input sensor 3 (I0/0) is set to OFF state and then C50.ACC source A0011If the flag 8 (B33/2) is set to ON state and timer 3 (T42) is set to base as 0.01 and preset value to 50 and ENABLES the output actuator 4 (o0/1).0012If the flag 8 is set to ON state and the timer 3 (T42) is decreasing and then LATCH the flag 9 and UNLATCH the flag8.0013If the flag 9 (B33/3) is set to ON state and then set the counter down by 1.0014If the flag 9 is set to ON state and the input sensor 3 (I0/0) is set to OFF state then LATCH the flag 10 and UNLATCH the flag 9.0015If the flag 10 (B33/4) is set to ON state and the input sensor 9 (I0/5) is set to ON state then LATCH the flag 7 and UNLATCH the flag 10.Stage 40016If the flag 11 (B34/1) is set to ON state and the input sensor 6 (I0/6) is set to ON state and then LATCH flag 12 and UNLATCH flag 11.0017If the flag 12 (B34/2) is set to ON state and the input sensor 8 (I0/2) is set to ON state then UNLATCH the flag 12 and LATCH the flag 13.0018If the flag 13 (B34/3) is set to ON state and the input sensor 8 (I0/2) is set to OFF state then LATCH the flag 11 and UNLATC H the flag 13.0019If the flag 11 (B34/1) is set to ON state and the input sensor 8 (I0/2) is set to ON state then UNLATCH the flag 11 and LATCH the flag 14.0020If the flag 14 (B34/4) is set to ON state and then ENABLE the output actuator 5 (o0/2).0021If the flag 14 is set to ON state and the input sensor 8 (I0/2) is set to OFF state and then LATCH the flag 11 and UNLATCH the flag 14.0022END7. The Rejection ComponentIn PLC, the unassembled components are rejected by the sensor 8 (I0/2). The problem in which the unassembled components are rejected due to the delay in the actuator 4 or the peg which causes from the peg chute initially but not the ring or the assembled components which comes from the sensor 3 moves a bit distance at which the sensor 6 cannot detects the component then the rejection of the component could be taken by the sensor 8. And also there must be delay in the actuator 3 in order to push the rings in to the chute. These are the reasons for the rejection of the ass embled and unassembled components.8. TestingThere are four tests to check whether the PLC is working under conditions or not. The first test is to check whether the sensor one is detecting the peg or not and the actuator 3 is knocking the ring into the chute through the detection of sensor 2. The second test is whether the actuator 4 is holding the ring in the ring chute for some delay of time and allowing only the rings through detection of sensor 2. The third test is to check the whether the sensor 6 is detecting the assembled components at the lower sort area. The fourth test is to check the actuator 5 at the solenoid in order to reject the unassembled components.9. DiscussionIn modern control systems, the mechanical and electrical parts are used to design the machinery. In most of the control systems, there is a relay in the circuits, programming controllers and some other special devices are used. There are several ways to select the PLC. The most important in selecting the PL C is the processor. The cost of the system is very cheap and it is reliable and flexible. In PLC the user program cannot be analyzed.The main benefit of the Programmable controllers is the flexibility. The effectiveness of the use of the PLC is the software controller in which the PC software solution that relates devices via communications protocols. The main focus is based on the programming languages. These languages are built with the logic of the various instruction set.The following are the methods for selecting the PLC are1) Maximum number of inputs and outputs is allowed. (Digital, analogue, inputs, outputs).2) Layout of sensors and actuators. ( peripherals)3) Nature of solution.( New or existing)4) Special signals and modules. (high speed digital outputs)5) Processor properties. (program and data memory)6) Working conditions. (temperature, humidity, dust)7) Communications. (ASCII)8) Specialities of program. (special functions)The limitations of the PLC are1) To store a larg e amount of data, the program controllers are not capable with sufficient memory.2) The temporal network which is traceable by hardly overloads can cause the issue in automation system communication.ConclusionThe solution that set the industrial standard is the Allen-Bradley Micrologic 1000PLC. For the digital I/O, the micrologic 1000PLC are available in 10-points,16-points and 32-points and whereas fort the analogue I/O, the micrologic 1000PLC are available in 20-points digital I/O, with 4 analog inputs and 1 analog output. The successfully method for the Allen-Bradley manufactures-lower costs, flexibility, high quality and fast start ups. This control method has been successfully invented by the PLC program. The major parts of the PLC are sensors, solenoids and actuators. These sensors and actuators will acts as a vital role in the PLC. The pegs and the rings that come on the upper sort and lower sort area can be detected through the sensors. Thus, by placing the sensors and actua tors in the suitable place, the rings and pegs can reach the destination successfully. The program is tested and thus the results is achieved successfully without any errors.
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