SQO help needed

HI Guys,

I need help understanding the SQO instruction and everything that goers with it including the data table. I'm taking PLC's at night school and I was told we will have a practical lab to do for my midterm exam and we will also have to pre populate the data table. So confused here. Next we will be doing the SQL instruction

Thanks

Mesels said:

HI Guys,

I need help understanding the SQO instruction and everything that goers with it including the data table. I'm taking PLC's at night school and I was told we will have a practical lab to do for my midterm exam and we will also have to pre populate the data table. So confused here. Next we will be doing the SQL instruction

Thanks

Click to expand...

Any particular brand of PLC?

using AB plc 5

Mesels said:

using AB plc 5

Click to expand...

Ok, start with Chapter 12 of the Instruction Reference Manual.

http://literature.rockwellautomation.com/idc/groups/literature/documents/rm/1785-rm001_-en-p.pdf

Then come back with questions.

Hint:

I find it a lot easier to lay out Sequencers using Excel, then transfer the Data to the PLC Sequencer Table.

Stu....

sthompson said:

Ok, start with Chapter 12 of the Instruction Reference Manual.

http://literature.rockwellautomation.com/idc/groups/literature/documents/rm/1785-rm001_-en-p.pdf

Then come back with questions.

Hint:

I find it a lot easier to lay out Sequencers using Excel, then transfer the Data to the PLC Sequencer Table.

Stu....

Click to expand...

I have never done it in excel. Do happen to have a excel example / template you would be willing to share?

WOW i Just noticed that i broke 1000 posts. Does not seem like i have been on here that long.

I actually use a spreadsheet myself (but I generally use my own sequencer, SQI/SQL/SQO isn't very flexible).
My sheet just builds up the feedback DWORD, a feedback mask DWORD, an output DWORD and an output mask DWORD from bits to hex numbers.

I use masks that ignore any "Don't Care" state (not flagged in my worksheet as hard true or hard false).

I concur with RDRast on this. I use the MEQ/MOV (or MVM if I really need to mask outputs) with indirection in favor of the SQI/SQO pair so that I can control the step number separately. One other thing that the stock SQI/SQO pair does that I don't like, is that if you change to a step in which all the input conditions are true, you don't get the false to true transition required to go ahead and move on the the next step. You can work around this with oneshots and extra stuff, but I prefer to just roll my own step increment logic.

For a very basic example of using excel with the MEQ/MOV (16 bits wide, but easily expandable) see here:

http://forums.mrplc.com/index.php?app=downloads&showfile=854

Hi Guys,

I now have better understanding of the sqo though I'm not sure about the data table. I just wet through a practice midterm test. I actually have the program and a answer to the data table but I 'm not sure if I understand it. Can someone help if I send the file to them or can I upload the file

Thanks Mesels

Mesels said:

Hi Guys,

I now have better understanding of the sqo though I'm not sure about the data table. I just wet through a practice midterm test. I actually have the program and a answer to the data table but I 'm not sure if I understand it. Can someone help if I send the file to them or can I upload the file

Thanks Mesels

Click to expand...

If you are using a PLC5 and RSLogix5 then zip the .RSP file and post it here.