How do I loop an instruction set XX number of times using Click PLC?

[NewGuy2024]

Complete noob here, using a Click C0-02DD1-D to run a test stand. Requirement is to turn on motor run for X seconds, turn off and dwell for X seconds, turn on motor run + reverse for X seconds, turn off and dwell for X seconds, repeat XX times then stop.



I have managed to create a working cascade of 4 timers followed by a counter, I cannot figure out how to loop back so it will run XX cycles. I can get it to work one cycle at a time by pressing a hard wired PB to X1.



Consecutively with the timers I need an output (Y3) and an analog voltage (AD1V) to be on throughout the full number of cycles.



I have the PLC in a test box right now with hard wired switches & indicator lights, I will be using a C-More HMI in the actual test stand.



Any help would be appreciated, this is the first of many test stands I want to automate, current (partial) program attached (.ckp).

 

[Cheeseface]

Try using an integer to determine what step you're on. Then all you have to do is change it to the start of the sequence.

e.g.:

if step = 0 and blue_push_button set step = 1
if step = 1: run timer1
if step = 2: run timer2
if step = 3: run timer3
if step = 4: run timer4
if step = 5: increment counter

if timer1 done: set step = 2
if timer2 done: set step = 3
if timer3 done: set step = 4
if timer4 done: set step = 5
if counter done: set step = 0, else set step = 1

if step = 1: run motor
etc.

 

[Jeev]

**EDIT - Beaten to it before I hit the post button

If your sequence is always going to be the same then it seems like a state/step based routine would be a nice, clean way of doing it. That will also make troubleshooting and changing it later a bit easier.

Start by defining your States/Steps in simple terms:

0: Waiting to start
1: Clear count
2: Turn on motor fwd for X seconds
3: Turn off and dwell for X seconds
4: Turn on motor rev for X seconds
5: Turn off and dwell for X seconds
6: Increment count
7: If count is XX then go to 0 - Otherwise go to 2.

You could also combine some of these together and reduce the number of states.

 

[NewGuy2024]

Thanks for the quick reply Cheeseface - I have to admit I'm not sure what you mean with the steps. I have the 4 timed cycles running satisfactorily, I just need to repeat the sequence say 25 times. I am wondering if the timers should be in a drum that can then be run XX number of times.

 

[drbitboy]

You were pretty close, only needed one more branch:

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The CTD1 counter value is the "step" referred to by @CheeseFace and @Jeev.

 

[drbitboy]

There is more than one way to skin a cat: the attached image implements the 4s+4s+4s+3s cycle with one timer. Also, rungs 2-4 could be more or less replaced by a single Drum instruction.

 

[drbitboy]

TOF makes it even shorter:

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