Making sense of Stages, Autom/direct

Hi, I am a keen omron user, and came across an automation direct plc on a site that was failing. I managed to snap it out of it long enough to pull the program. I have not really used SFC with omron but I moslty understand the similarities and I mostly understand the symbols in the program from the AD plc, but was wanting clarification on the stages thing if poss.
- With multiple ISG stages, are these all run at first cycle sequencially and does the cpu keep scanning through them until a jump is made?
- If another stage is set in one of the ISG's does the cpu then run ONLY that stage? or all ISG stages AND the stage that has been set?
- In this particular progam there are a pile of relays in the first ISG that have stage names, S31 - S41 for example that energise a virtual coil - how are these relevant if the cpu is only executing a single stage?
- If the program is cycling through the stages with the JMPs, what happens if the conditions are not met in that stage the carry on? does the program just sit dormant? (in some stages there is only a JMP, no reset or anything.
- can the cpu run many stages simultaneously if they are set?
- coming back to the ISG thing, there are ISGs dotted here and there between stages 1 - 53 in this case. why an ISG not a SG if its just another stage?
- in one rung there is an SP3 with 1 minute, going into an SGCNT with a 3600 constant value, I take it this execution condition is met after 3600minutes, but what is SP3 and SP4, I cant find what these special relays are? Just a clock pulse right? and if the SGCNT has an UP in front of it I take it that it is upward differentiated?
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bit of a novel, just keen to get my head around the stages thing, I have not encountered it before. I am a bit limited in what I can do with the software as I only have the free version, but the file is too big, so I currently have it open and have screenshotted it, but I thought I'd try replicate it into an omron CP1L, to save a huge amount of time as there are no schematics onsite, and labelling is average to none.

Thanks,

- With multiple ISG stages, are these all run at first cycle sequencially and does the cpu keep scanning through them until a jump is made?

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Each ISG is turned ON at progrram start and continues to execute until a JMP is made in the stage or a RST of the stage occurs.

- If another stage is set in one of the ISG's does the cpu then run ONLY that stage? or all ISG stages AND the stage that has been set?

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A SET of another stage leaves the current stage ON. A JMP, besides setting the target stage resets the current stage.

- In this particular progam there are a pile of relays in the first ISG that have stage names, S31 - S41 for example that energise a virtual coil - how are these relevant if the cpu is only executing a single stage?

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By 'relays' do you mean output coils or contacts? If they are output coils then each of those stages, when encountered during the scan, will execute. If they are contacts then the logic is testing the state of the stage.

- If the program is cycling through the stages with the JMPs, what happens if the conditions are not met in that stage the carry on? does the program just sit dormant? (in some stages there is only a JMP, no reset or anything.

Click to expand...

As mentioned above, a stage, once turned on, will stay on until a JMP inside the stage is executed or it is the target of a RST.

- can the cpu run many stages simultaneously if they are set?

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Like any other PLC the code is executed in a scan manner. ON stages are executed when they are encountered. Though in most cases this is quick enough to be considered simultaneous.

- coming back to the ISG thing, there are ISGs dotted here and there between stages 1 - 53 in this case. why an ISG not a SG if its just another stage?

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The ISG just ensures the stage is enabled at start. I typically have just one ISG at the beginning of the program and include SETs of the other stages I desire there then JMP to the next stage. Different ways of accomplishing the same thing.

- in one rung there is an SP3 with 1 minute, going into an SGCNT with a 3600 constant value, I take it this execution condition is met after 3600minutes, but what is SP3 and SP4, I cant find what these special relays are? Just a clock pulse right? and if the SGCNT has an UP in front of it I take it that it is upward differentiated?

Click to expand...

There are free PDFs at AutomationDirect for each CPU. (You didn't mention which this is.) SP3 and SP4, in the DL06, are the one minute and one second pulses respectively - 50% duty cycle. Yes the SGCNT increments on the UP edge. The PDFs also have an introduction to stage programming.

See also DL205 user manual, chapter 7 : http://www.automationdirect.com/static/manuals/d2user/d2user.html

Bernie thats Gold thanks, answered all my wonderings in one swoop!
cpu is an D0-06DR, I'll get the cpu manual shortly, and will start on the omron code.

Cheers, Stew

Glad I could help. Check back with any more questions.

There is also the AutomationDirect forum

Thanks Bernie, are you fluent in CX programmer?
Would you say that an OUT coil used as a one shot in DirectSoft would be able to be subtituted with an upward differentiated contact operating a coil in CX?
I wrote a prog just before as a direct substitution for the directsoft one, due to time constraints and non-information from the other site.
Cheers,
Stew

Found it, the UP instruction, I had not used this one before. learning all the time. Managed to successfully create a standard ladder program on omron from a staged auotmation direct program and install in a few hours. Was so lucky that I was able to grab a program off a faulting CPU, even though I had the free version of Directsoft (200 rung program) so i was able to swap it over onsite without any hassle and having any downtime due to no wiring schematic. Happy!
Thanks again Bernie, you helped heaps
Stew