AB CompactLogix Memory Estimate 1

[jwilson3]

I'm investigating using the subject PLC to control a wastewater treatment process. I'm planning on 20 digital I/O and 16 analog I/O and I'm trying to estimate the memory needed. The AB selection guide gives a memory of 4000 bytes needed per controller task, but I'm not clear on what constitutes a "task". Is each "rung" a task, or is each "instruction" a task?

 

[itsmoked]

I suspect you will see somewhere a list of "tasks". A task is probably something like a PID algorithm. OR a data base function. Some canned function. A whole lot of PLCs don't even have that much memory total but support thousands of rungs so it can't be just a rung.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[jde777]

Here you go...

http://literature.rockwellautomation.com/idc/groups/literature/documents/gr/lg5000-gr001_-en-p.pdf

 

[itsmoked]

Excellent jde777!

Page 30.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com