Studio5000 Local variables in AOI

Hi all

one question about Logix5000 and AOI:
normally I work with Siemens, and I use FBs with multi-instances

Now I need to transpose the software on studio5000
At the moment unfortunately I cannot test anything on phisical CPU, so i need to know if the local variables of AOIs are the same of STAT data on Siemens, so:

1. Local variables of AOI are retentive or the value is deleted at every PLC scan?
2. Is it possible to go online and see the value of local vars of each instance of an AOI? Even if local data are complex structures like Timers, counters or other AOIs data type?

Thank you!

Hello,

The answer is Yes and Yes

Local variables are retentive and not get cleared after each scan time
You can monitor variables in any instance of your AOI regardless data type

Thank you Chopin.

So in order to work like Siemens' Multi-instance, the way is declaring AOIs as local variables of another AOI

is it correct?

Thank you again

italo2008 said:

So in order to work like Siemens' Multi-instance, the way is declaring AOIs as local variables of another AOI

is it correct?

Click to expand...

I am not sure if I understand what you mean.
Siemens works slightly different than Rockwell.
When you add your AOI you create a tag name of you AOI data type - it is like instance db in siemens

Also be aware that in Rockwell you cannot edit you AOI online unlike in Siemens. You would need to go offline edit and download which is stopping PLC.
So if you thing this might be an issue you should not use AOI.

In Siemens I can create nested FBs. If the inner FB (FB2 for example) is declared as MultiInstance, I can declare in the STAT variables of the outer FB (FB1 for example), as many vars as I want of FB2 type, and call each of them in the outer FB.

For example, FB2 manages one valve
FB1 manages 50 valves, so in FB1 there are 50 instances of FB2.

I need to do the same in studio5000, and I was asking is if the way to do this is declaring many instances of inner AOI as local variables of the outer AOI

If you need to do it as you say you could use UDT and add as many members of your AOI as you need

RA's AOIs can't access variables outside of their own scope unless passed to them as in/out parameters. You can nest AOIs inside of AOIs but passing variables is as I indicated. Variables declared from UDTs are useful.

RA's AOIs can't access variables outside of their own scope unless passed to them as in/out parameters. You can nest AOIs inside of AOIs but passing variables is as I indicated. Variables declared from UDTs are useful.

Click to expand...

Ok. thank you