CompactLogix & Event Interrupts

Hi all,

I have a question regarding CompactLogix & Event Interrupts.

Question is how many event interrupts can the CompactLogix has?

Thanks.

Are you referring to periodic tasks?

The CompactLogix is capable of four tasks. So if you have one continuous task then you could have a max of three event tasks.

OG

lostpatrol1 said:

Hi all,

I have a question regarding CompactLogix & Event Interrupts.

Question is how many event interrupts can the CompactLogix has?

Thanks.

Click to expand...

I think the Compactlogix can only trigger an Event task using the EVENT instruction. The Compactlogix can handle 16 tasks, with one being continuous, therefore, 15 can be event tasks




Ian

There are several different CompactLogix controllers, each with its own capacities. The 1768-L43 has the most tasks, and the 1769-L31 has the fewest.

Here's a comparison, with specifics about Event-based Tasks:

http://www.ab.com/en/epub/catalogs/12762/2181376/2416247/407648/

Hardware generated interrupt...like the DII in the SLC 500 family. However SLC 500 only has one.

So, CompactLogix has 15 Events-trigger "interrupts"?

Thanks

re-post with details.

There are several different models of CompactLogix controllers.

Each model of CompactLogix controller has a different memory capacity and a different task capacity. The newest controller, the 1769-L43 with integrated motion control, has the most tasks (16), while the 1769-L31 controller has 4.

Any Logix-family controller can run only one Continuous Task, but the other tasks can be any mix of Periodic or Event type.

This Allen-Bradley catalog page describes some of the differences between CompactLogix controller models:

http://www.ab.com/en/epub/catalogs/12762/2181376/2416247/407648/

The web page behind that link includes the following information:

1768-L43 16 tasks (1 continuous task).

For the 1768 controller, Event Tasks can be triggered by Consumed Tags, EVENT instructions, axis, and motion event triggers.

1769-L35x: 8 tasks (1 continuous task).
1769-L32x: 6 tasks (1 continuous task).
1769-L31: 4 tasks (1 continuous task).

For the 1769 controllers, Event Tasks can be triggered by EVENT instructions and Consumed Tags.

What is missing from both of those descriptions is the ability to trigger an Event task from a discrete input. Because the 1769 Compact I/O bus has a fixed RPI of 2 milliseconds, there is no individual module interrupt function like there is in the 1756-series backplane. The 1769-BOOL module helps leapfrog this limitation with sub-millisecond I/O reaction times.

What's your application for event interrupts ?

My application is can seaming equipment. One can one lid, no can, no lid

So, I have and input which on rising input, interrupts the main routine and see if there is a can present. If a can is present, release a lid, if no can, don't release.

So, I need an interrupt for this input.

funny I had exactly the same application a couple years back with another company that insisted that we use a separate plc just to handle the nc/nl. lol