Maybe I can make some errors in syntax but a decision for this task: VAR MS: BOOL; (**Master switch**) ULS: BOOL; (**Upper Limit switch**) LLS: BOOL; (**Lower Limit switch**) iState:int:=0; (**state of machine**) END_VAR; VAR_OUTPUT UP_COIL:BOOL; DOWN_COIL:BOOL; END_VAR_OUTPUT CASE iState of 0: (**init**) IF NOT MS THEN iState:=1; END_IF; 1: IF MS AND NOT ULS AND NOT LLS THEN iState:=2; END_IF; UP_COIL:=FALSE; DOWN_COIL:=FALSE; 2: IF MS AND ULS AND NOT LLS THEN iState:=3; END_IF; UP_COIL:=TRUE; DOWN_COIL:=FALSE; 3: IF MS AND NOT ULS AND LLS THEN iState:=4; END_IF; IF NOT MS THEN iState:=1; END_IF; UP_COIL:=FALSE; DOWN_COIL:=TRUE; 4: IF MS AND ULS AND NOT LLS THEN iState:=3; END_IF; IF NOT MS THEN iState:=1; END_IF; UP_COIL:=TRUE; DOWN_COIL:=FALSE; ELSE iState:=0;END_CASE;
@ACCautomation
7 жыл бұрын
Your logic looks good. I would add to 0: (*init*) UP_COIL:=TRUE; DOWN_COIL:=FALSE; This would ensure that when the master switch is off, the process is in the retracted position. Great job, Garry
@braincrackz
6 жыл бұрын
New things to learn to get..im gonna learn and study the truth table. as always wonder educational vide about PLC where people dont see. keep it up.
@ACCautomation
6 жыл бұрын
Thanks for the comment Abu. Garry
@devendrasadashivbhagwat1314
6 ай бұрын
Very useful, informative video 👍🏻 but, background music is louder than the teacher's voice, so it is a bit difficult to hear explanation.
@ACCautomation
6 ай бұрын
Sorry for that. This was done several years ago. We have learned and improved since this video was released. Thanks, Garry
@devendrasadashivbhagwat1314
6 ай бұрын
No problem sir. Information is so useful that I got it with concentration. Thanks a lot for the prompt reply. 🙏🏻👍🏻
@ACCautomation
9 жыл бұрын
The idea of the sequence table is to develop the programming logic. It is similar to a flow chart but looks at all of the inputs and outputs at once. The important thing to do is follow the logic. The steps are similar, and in this application is where the cycle ends and begins again. The actual program works that was developed with this logic. If you follow the sequence with the PLC program on the website you will see how the PLC logic is developed. accautomation.ca/five-steps-to-plc-program-development If you search the website on sequence tables, there are other examples. Thanks Virban for your comments.
@joew4202
3 жыл бұрын
What if you don’t have a sequence table. When I get prblems I get a paragraph stating what the circuit is supposed to do
@ACCautomation
3 жыл бұрын
Hi JJ W, When you have the paragraph, list the inputs and outputs required for the task. Then translate this into a sequence table. This will help clarify the logic. accautomation.ca/five-steps-to-plc-program-development/ Regards, Garry
@virbaniulian9048
9 жыл бұрын
Step1 & 5 of inputs are the same (also step 6 fit into this), but the outputs are different for same input combination. Are you sure this is working without bugs? On the other hand... having 1 output written dozens of times in a program makes it impossible to troubleshoot. Let's assume you want to troubleshoot why solenoid is down. It may be because it was set, or reset? and from where in the program? You forget to insert the step variable in your program. Correct will be to say IF I am in step 1 and Master Switch is 0, go to step 2. If in step 2 and ... then go to step 3, and so on. In the end, just say Up solenoid active in steps 2,4 and 5 and down active in step 3. Anyway, congrats for your work.
@ACCautomation
Жыл бұрын
Hi Virban, The sequencer troubleshooting is ideal for using an HMI. The operator can see the input bits expected and the input bits current. This can be very benefitial on a troubleshooting screen. Regards, Garry
@qzorn4440
7 жыл бұрын
Is there a way to link the plc logic in with an autocad diagram to locate where a faulty sensor is on a large machine to save time in troubleshooting? thanks.
@ACCautomation
7 жыл бұрын
There is nothing that would work directly that I know of yet. I have seen people convert the drawing to a picture. Then use a program like AdvancedHMI to highlight an area of the picture. AdvancedHMI is a VB.Net program that runs on visual studio. It has drivers for a number of PLC manufacturers. This is a free software. sourceforge.net/projects/advancedhmi/ Regards, Garry
@Decanewolf
11 ай бұрын
How do you create machine operation animations? Yours is kinda good!
@ACCautomation
11 ай бұрын
Hi @Decanewolf, I use the free online gif maker from CANVA. www.canva.com/create/gif-maker/ Regards, Garry
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