![As youcan see fromthe picturesabove thatthis program workswithmultiple inputsfromI:5.
Conclusion:
Withthese labssome of themask to use differentsimulators.Istill findusingthese difficultand
unhelpfulintermsof what’sactuallygoingon.Igot stuck inthe beginningwithhavingasubroutine
nestedinside myprogramsladderlogic.Thiscausedmysystemtocrashand not worksproperlyonce I
figuredthisoutI wasable to run myprograms withoutanytrouble.These were more advancedcontrol
programsthan what we have dealtwithbefore. Theselabshelpeduslearnmore aboutPLC’sandthe
advancedfunctionsthattheyare capable of.I enjoyedtheselabsandlearningmore aboutthe control
functions.
References:
Petruzella,F.(2011) LogixproPLC labmamual foruse withprogrammable logiccontrollers( fourthed).
NewYork,NY: McGraw-Hill
Petruzella,F.D.(2011). LogixPro PLClab manualforusewith programmablelogiccontrollers. NewYork,
NY: McGraw-Hill.
LogixPro(VersionTLP) [Computersoftware].(n.d.).](https://image.slidesharecdn.com/22c283cf-564d-4f4b-8335-7807c0e1f531-161028092351/85/PLC-unit-4-lab-Brett-Bloomberg-1-18-320.jpg)
PLC unit 4 lab Brett Bloomberg-1
- 1. EET310 – Programmable Controllers and Robotics Unit 4 By: Brett Bloomberg Instructor: William Routt Online EET Department ECPI University Date: 10/17/2016 ECPI’s Honor Pledge: I pledge to support the Honor System of ECPI. I will refrain from any form of academic dishonesty or deception, such as cheating or plagiarism. I am aware that as a member of the academic community it is my responsibility to turn in all suspected violators of the honor code. I understand that any failure on my part to support the Honor System will be turned over to a Judicial Review Board for determination. I will report to a Judicial Review Board hearing if summoned. Brett Bloomberg
- 2. Objective: Thislab helpedusbecome betterprogrammersbylearninghow tocontrol the PLCin termsof instructionsthatthe PLC needstocarry out.It was more data control insteadof usinginputsand outputswe were able tocontrol what rungthe PLCscode wasrunningwiththe use of the JSR,SBR, JMP, and LBL instructionsets.We alsousedmathand Binaryto decimal conversiontoturnonand off a thermocouple toindicate temperature.Thesewere advancedlabsthatreallyshowedushow to manipulate the code of the PLC. Lab 9-4 Thislab asksus to implementthe Jumptosubroutine PLCprogram.Withthislabwe demonstratedhow to use the jumpto subroutine instructionandhow it’sexecuted. Thisladderlogicwasn’ta difficultprogram, anditwasn’tdifficulttomake the jumpto subroutine,but whatthe studentshave tounderstandisthatyoucan’t have a SBR( whichissubroutine) andaJSR( Jump to routine) inthe same ladderlogicprogram.The subroutine isjustthata separate ladderlogicprogram that isnestedwithinthe systemthatyourmainprogramruns sothe programmerdoesn’thave tocode the same rungs multiple times. The inputsare shownbelow Off/OnI:1/0 StopI:1/1 Start I:1/2 SensorI:1/3 Motor O:2/0 PL1 O:2/1 Sol O:2/2 Tim T4:0 T4:1
- 3. The program is shownbelowwhichincludesthe subroutine. Runningjustthisprogramwill lockupthe PLC and cause it to fault.Thisisbecause youcan’t have a JSR and a SBR in the same program.The labdoestry to explainthatitshouldgointoa differentfile,butthe studenthasto knowwhattheyare reading.Withthisif labI believe itisagoodlearningexerciseto make the mistake of compilingthe wholeprogramonone line.Makingthismistake willhelpthe student learnthat we will make mistakesandithelpswiththe troubleshootingprocess. The picture below isthe normal programwithoutthe attachedsubroutine. Thisprogramispretty simple tounderstandonce youhave watcheditruna couple of times.The motorisreallyanythingjusta motor.The userof thisprogram will hitthe start buttonwhichwill lockthe motorintothe run position and will continuouslyrununtil the Stopbuttonispushed.Once the motorrunslongenoughthe sensor will tripandcause the systemtojumpintothe subroutine.Itwill alsoturnoff the Pilotlight.If the sensorisstill unmade andthe userhitsthe on off buttonthe Solenoidwill run.Thishoweverisonlya momentaryactionandwill notlockin the solenoid.The jumpinstructionsare below.
- 4. The subroutine picturedabove isasimple one.Whenthe sensorismade it will jumptocompletethe tasksthat are inthe subroutine.IaddedaprogrammerpurposesswitchsoIcouldstop the program in the subroutine andwatchit complete the logicthatiswithinit.Thisswitchdoesn’tneedtobe inthe program,but I addedit for my ownpurpose of observation.The timerT4:0will instantlystartcounting to 20. Once that isdone it turnson anothercounterwhichwhenthattimerT4:1 is runningPilotlight1 will turnon.Once the secondtimerisdone runningthe Pilotlightwill turnbackoff until the sensoris unmade againwhichwill turnthe pilotlightbackonagain. Conclusion: Thislab wasinterestingandreallyletusunderstandshow subroutinesworkedandthe parametersor instructionstheyneedinordertooperate properly.Ifoundthatonce youunderstandthatthe subroutine isaseparate file anda separate ladderdiagrameverythingstartstocome togetherandwork properly.
- 5. Lab 9-9 Thislab like the lastlabasksus to implementthe Jumptosubroutine.Thislabhoweverusesthe instructionof JMPand LBL whichare two otherunique control instructionsthatthe PLCcan use to control what logicisbeinglookedatwhen.Thisprogramisprettylarge intermsof everythingthatis goingon andthe inputsbeingused.The inputsare asfollows S1 I:1/1 S2 1:1/2 S3 I:1/3 S4 I:1/4 S5 I:1/5 S6 I:1/6 S7 I:1/7 S8 I:1/8 S9 I:1/9 S10 I:1/10 S11 I:1/11 S12 I:1/12 S13 I:1/13 PL1 O:2/1 PL2 O:2/2 PL3 O:2/3 PL4 O:2/4 PL5 O:2/5 PL6 O:2/6 The ladderlogicisas follows
- 6. The subroutine isasfollows WhenSwitchone ismade it turns onPL1. When S 2 is made itstarts the jumptosubroutine.WhenS3 is made thisIs whenitjumpsto the lbl whichstartsthe timer:However,thisonlystartswhenS7isalso made.S4 turns on PL 6. S9 isanotherjumpto the LBL to start the timeragain.Whichwhenitis done timingwill resetitself.S8turnson PL 2. S 10 jumpstothe subroutine.S11 turns onPL 4. The sub routine isinterestinginthatitneedsa few Switchesmade inordertorun properly.Withthe Subroutine S 13 needstobe made inorderto turn on PL 3. S12 needstobe made to inorderto jumpto the timerin the subroutine,butinorder forit to start timingS6 alsoneedstobe made. Thisis a simple programanddoesn’ttake muchto understand.Thisprogramdealsmore withthe logic control thenthe actual inputsandoutputs.Eventhoughwhenfirstlookingatthisprogramyouwould that that the Switchesare importanttothe functionswhichtheyare ina way, butthe real control isthe jumpcommandsand the subroutines. Conclusion: Thisprogram wasn’thard to make or eventounderstand.Atfirstglance itlookedalotharder thenwhat it reallywas.Ithelpedreinforce ourknowledgeof control commandsandinstructionsthatare more advancedthanthe basicinputsoutputlatchingwe have beendealingwith.
- 7. 10-18 Thislab asksus to implementthe setpointtemperature control of aheaterunit.The tank isto maintain a temperature of 102 Hex BCD witha catiationfrom100 Hex BCD to 104 Hex BCD betweenthe ON and OFF cyclesof the heater.Temperature control istobe appliedanytime the processisrunning. Demonstrate the correctoperationof the program.Use the batch simto simulate the program. The inputsas follows S1 ( ON / OFF) I:1/10 Thermocouple I:3thisisthe entire inputof the Input3 group. HeaterO:2/4 LED displayO:4 The program is as follows Thisis a simple program andwitha little knowledgethe abilitytounderstanditisjustaseasy.Whenthe Unit isturnedon itstarts to read the temperature of the tankwiththe thermocouple.Whenwe adjust the readingsof whatthe thermocouple shouldbe readingbyturningonthe inputsof positionunit3We can adjustand control what temperature the thermocouple isseeing.If the temperature reachesless than or equal to256 binarythe lowtempstayson. If the temperature goesabove 260 binarythe heater turns off.Once the heateristurnedonits lockedtostay onuntil the temperature goesabove 260 binary.The onlywaythe heaterturnson isif the user operatedswitchisturnedon.
- 8. Conclusion: As youcan see fromthe picturesabove if the temperature seenbythe thermocouple islessthanor equal to256 binarythe heaterremainson,butif that goeshigherthan260 the heaterwill turnoff.This isa simple datacontrol ladderlogicprogramthat usessimple datacomparisonsandvariable input rangesto determine whatthe systemdoes.Iwouldalsoimagine thatthissimplecircuitiswhat’susedin a thermostatinour homesforheat,or ac. It couldbe a userset temperature justbyvaryingthe settings a little bitfroma LCD displayif needed.The possibilitiesof thissimple code reallygofarbehinditsbasic use.
- 9. Lab 10-22 Thislab asksus to implementthe datacompare program.It asks usto determine atwhataccumulated countervaluesthe pilotlightswill turnonandbe energizedandthe highestcountbefore the counteris reset. Thislab isa fairlyeasyprogramto understand.The ladderlogicallowsthisbythe use of checkingthe counterscountand comparingthat numbertoa setof differentcommandsinthe formof ladderlogic The fistrung inthe setof commandsto check the counterisa greaterthanor equal towhichresetsthe counterafterit reachesa certainnumberinthisinstance thatis19. The secondrung issimplyanequal to rung.If the counterequalsthisnumberturnon the pilotlightwhichisprettyeasytounderstand.The thirdrung of thisprogram is a little different.Ithastwoprecise measurementsthatturnonthe pilot lightif meet.The firstrequirementof the counteristhatthe counterneedstobe higherthan5, but it alsohas anotherinstructionthatthe numberhasto be lowerthan9. Thismeansthat inorder to turnon pilotlight2 the counterhas to be betweencounts5and 9. The thirdrung isverymuch like the lastwith the counterneedingtobe between10and 18.
- 11. Conclusion: As youcan see fromthe picturesthat pilotlight1 andpilotlight2 will notactivate at the same time since the firstsolutiontoenergizingpilotlight2isthat the counter hasto be greaterthan5. If it was equal to5 it wouldactivate.Thiscouldcause forerrorsdownthe line if the programmerhappenedto make it.This wasa fairlysimplecomparator programwhenthinkingaboutit,yetwhenyouneedtodo thiswithin logicsprothingsdobecome interesting.CountingwithinPLC’sisaninterestingtopicwiththe data manipulationthatcanhappen.Beingable tokeyintocertainnumbersof the countertodo certain thingslike change the mixture of aliquidthat’sbeingpouredintoatankbasedonhow many gallons have alreadybeenpumpedintothe system.Itdoesallow foraversatile application.
- 12. Lab 11-4 Thislab asksus to implementthe overfillalarmprogram.Inthisapplicationthe subtractfunctionisused to indicate avessel overflow condition.Itrequiresanalarmtosoundwhenthe systemleaks2 poundsor more of raw material intothe vessel afterapresetweightof 5 poundshasbeenreached.Withthiswe use the BCD sim. The inputsare as follows: Stoppb I:1/0 Start I:1/1 WeighttransducerI:5 Fill SOLO:2/0 FillingPLO:2/1 Full PL O:2/2 AlarmO:2/3 Withthislab we usedthe I:5 inputfieldwhichispartof the inputoutputs.Ididnot take a snap shotof thisbecause forme at the time Ididn’tthinkitwas important.Ididuse it duringthislabbut failedto take a screenshotof the actual numbersthatthe scroll wheel allowed.Ididtake a lotof picturesof the program as itwas running. The firstrung is the basiccontrol rung that turnson and off the solenoidandthe solenoidoutputlocks inthe momentarypushbuttonforthe systemtokeeprunning.The programwill keep the Solenoid active until the systemisgreatthanor equal to5. Whenthisisgreaterthan or equal to 5 the outputfor the tank beingfull isturnedon.Thisturnson anotherrungwhichsubtractsthe amountof water that was filledintothe tankby5. If thisnumberislessthan2 an alarm will sound. The alarmwill soundif the systemleaks2 poundsormore of the water.That goesintoa 5 galloncontainer.
- 15. Conclusion: Thislittle programdoesdoa lot of good.I wouldsayin orderfor itto run automated.The I:5 would needtobe an actual weighttransducer.Thismachine doesn’tnecessarilyhave touse waterexclusively, but if itdid youwouldneedtochange the sensorto a flow sensor.Once the systemsees5poundsit shouldshutoff the pump.
- 16. Lab 11-14 Thislab asksus to implementthe conversionfromCelsiustoFahrenheit.Inthisapplicationthe thumbwheelswitchindicatesCelsiustemperature.The programisdesignedtoconvertthe Celsius temperaturestoFahrenheit valuesfordisplay.Use the BCDsim. Withthisprogram I tookpicture of the I:5 inputand whatthe numberswere at,and the conversion wouldbe displayedinthe I:6column.Thiswasa verysimple datamanipulationprogramthatjust requiredalittle forthought. Takingthe numberenteredandconvertingfromCelsiustoFahrenheitisn’t a hard task to complete aslongas youknow the formula. Firstwe multiple the numberby9 thenwe divide the numberby5. Once thishas beendone we add32 to the total numberwhichgivesusthe conversionfromCelsiustoFahrenheit. Thisladderlogicisbroken up intoeachrung preformingacertainfunctionof the formulatoconvertCelsiustoFahrenheit.
- 18. As youcan see fromthe picturesabove thatthis program workswithmultiple inputsfromI:5. Conclusion: Withthese labssome of themask to use differentsimulators.Istill findusingthese difficultand unhelpfulintermsof what’sactuallygoingon.Igot stuck inthe beginningwithhavingasubroutine nestedinside myprogramsladderlogic.Thiscausedmysystemtocrashand not worksproperlyonce I figuredthisoutI wasable to run myprograms withoutanytrouble.These were more advancedcontrol programsthan what we have dealtwithbefore. Theselabshelpeduslearnmore aboutPLC’sandthe advancedfunctionsthattheyare capable of.I enjoyedtheselabsandlearningmore aboutthe control functions. References: Petruzella,F.(2011) LogixproPLC labmamual foruse withprogrammable logiccontrollers( fourthed). NewYork,NY: McGraw-Hill Petruzella,F.D.(2011). LogixPro PLClab manualforusewith programmablelogiccontrollers. NewYork, NY: McGraw-Hill. LogixPro(VersionTLP) [Computersoftware].(n.d.).