SLC500 STI where is it in Controllogix ???

We used to use an STI file in RSLOGIX500 IE: S:31 = 3
and then we would throttle S:30 from the main program changing the speed at which the STI would work at on the fly, this creates a Ramp that stays accurate and is not based on Scan time.

Where is this function in Controllogix ??

In my example we would add 1 to an integer or subtract 1 from an integer with limits of 0 - 1000 (equivelant to 1000 graduations of a potentiometer). The throttle (S:30) would be adjusted if we were to accelerate (take longer) and decelerate (shorten the time) in the case of an E-stop would reduce the decel time even more.

We considered these as processor 'ticks' that were adjustable. Can this also be replicated or done in the COntrollogix platform ?? If so please show me as this is crucial to a program conversion we are doing.

Thank you

The SLC-500 had a single Selectable Timed Interrupt that would execute a single Ladder Logic routine.

The ControlLogix has up to 31 Periodic Tasks, which can run ladder, structured text, or function block routines. The Periodic Tasks are fired by the ControlLogix system clock, which makes them largely insensitive the the execution time of the logic in the Continuous Task.

You can modify the execution period of a Periodic Task by using a Generic MSG instruction (RA Knowledgebase AID# 19591) but it might be better to just use the Periodic Task at a known fast rate and write a ramp algorithm.

There's an example of using a Periodic Task to generate a ramp function in the RA Knowledgebase, Article ID 69361.

Ken, thanks for the quick reply, I have a lot on my plate as it is. (I have to interface a created RSVIEW32 working screen to a L35E. Like I said the original system was a 5/05, 4 years later I am working on Version 2 Upgrade everything with the same start up time 2 - 3 weeks. I do not have access to Rockwell data base. So if anyone can send me a copy of the Rockwell files Ken is referring to It would really be appreciative.

Thanks to all for any assistance.

Regards

Ronny [email protected]