Time stamp event logger with RSLogix5000

[rroze002]

Hi all,

I am using a CompactLogix L45 controller with RSLogix5000 to run a silo management program. I'm logging the real time of certain events using an array and the MOV command, where I call for the system time and move it to the array.

This 'data logging' method works fine, but it is not very elegant and is heavy on the system resources. Can anyone suggest a better way for implementing event logging (w/ time stamp).

Thanks in advanced.

 

[Donnchadh]

Hi

You could connect it to excel and then write some vba to index the values done along as you have done with the array. Part of your vba could also do an auto save and start a new sheet at midnight or what ever event you wanted.


Donnchadh

 

[jkerekes]

No HMI software used in the system? They usually have a Datalogging function.

 

[rroze002]

I'm using the PanelView1500 HMI in this application. The datalogging that comes with Visual studio is more suited to logging values, not so much for time stamping.

Donnchadh - I don't have any experience with exporting/connecting to excel, can you explain this more.

 

[Donnchadh]

Hi

No problem

If you can connect a pc to the system and install a opc server (there are loads out there but rs linx gateway will do also not lite)

You can then use this to display values from the plc into excel.
If you google display values from Allenbradley plc to excel you will get help.
If you can't find them I can send you some just pm me.
Now when the values are in excel you can use the vba in excel to do lots of things like auto save based on the time of day or other things

Donnchadh

 

[rroze002]

Got it. I will give this a shot.

Thank you.

 

[daba]

rroze002 I think your method (logging in the controller) is preferable to logging anything in the HMI. What if the HMI is taken offline for any reason, it could miss an "event", and your logged data is now junk.

IMHO an HMI is a window onto the processor, and I contend that data-logging in the HMI is an even bigger resource hog than suitably configured Event Logging in the controller.

I don't know what triggers the logging, but you could place all of the necessary logging code in an Event Task, and trigger it when the event occurs, this way the controller only executes the logging code as required.

There are several ways to trigger an Event Task, there is even an Event instruction you can place in your normal code to trigger it, but that's pretty much the same as a conditional subroutine call. The only time you might need to configure it as an Event Task is if it is needed by multiple Programs.