ControlLogix Scan time and Overhead

Join Date
Jun 2017
Location
Lisbon
Posts
24
Hi Gents,
I am here with an 1756-L73 with a partner 1756-L7SP.
This is for an hydraulic press machine, with an very critical scan.

I need your help to clarify the following:
The values below, comes from the Properties>Monitor in each Task.

The current Motion Scan is 0,5ms, and 10ms for the Base Update Period.
The Safety routine has a scan time of 7ms.
The Continuous and only the task in the code has 42ms of scan time (Main Task).
The System Overhead Time Slice is 50%.
They do not use any Periodic Task.

So, my question is: When is executed the background routines, as communication?
Should be after the Main Routine 42ms, but....I do not know if this can run with System Overhead Time Slice at 50%.

I think that the Main Task ( the only task in the code), it is interrupted several times.
I cannot use the Task Monitor to confirm this above because I am using the RSL5K version 31.

Any help?
:rolleyes:
thank you!
 
Hi Gents,
I am here with an 1756-L73 with a partner 1756-L7SP.
This is for an hydraulic press machine, with an very critical scan.

I need your help to clarify the following:
The values below, comes from the Properties>Monitor in each Task.

The current Motion Scan is 0,5ms, and 10ms for the Base Update Period.
The Safety routine has a scan time of 7ms.
The Continuous and only the task in the code has 42ms of scan time (Main Task).
The System Overhead Time Slice is 50%.
They do not use any Periodic Task.

So, my question is: When is executed the background routines, as communication?
Should be after the Main Routine 42ms, but....I do not know if this can run with System Overhead Time Slice at 50%.

I think that the Main Task ( the only task in the code), it is interrupted several times.
I cannot use the Task Monitor to confirm this above because I am using the RSL5K version 31.

Any help?
:rolleyes:
thank you!


System Overhead Time-slice seems to be on the high side, but it can be set high, but make sure that you check the box to run the continuous task during unused time-slice period. That way once all the communications (including I/O data) is done, the controller gets back on with executing your code, rather than doing nothing while waiting for it's time-slice period to end.

I cannot remember the time-slice interval, I think it is every 5mS
 

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