Micro 1400 How to store values in permanent memory

[bearsgone]

Hello
This is probably a very basic question but I can not seem to find an example.

I have Micro 1400 controller which does not seem to keep any values every time it is being update. Based on specs it has non volatile memory. I want to protect some counters and timers from being reset after power down or PLC update.

If somenody could clarify how to access that memory in RSLogix 500, it would be greatly appreciated!

Thank you

 

[sthompson]

Hello
This is probably a very basic question but I can not seem to find an example.

I have Micro 1400 controller which does not seem to keep any values every time it is being update. Based on specs it has non volatile memory. I want to protect some counters and timers from being reset after power down or PLC update.

If somenody could clarify how to access that memory in RSLogix 500, it would be greatly appreciated!

Thank you

Exactly what do you mean by "it is being update"? If you are referring to a Download, then yes, the Data in the Downloaded Program will overwrite the Data in the PLC. As to power loss, as a general rule memory values are retained if the Battery is good. On Timers (TON) Accumulator Value will reset on power loss. If you need to maintain a Timer Accumulated Value through a Power Cycle, use a Retentive Timer (RTO). This will also require you to Reset (RST) the Timer. Counters will retain their Count Value through a power loss.

Refer to the Micrologix 1400 Instruction Reference 1766-RM001A-EN-P. It will explain how the Instructions will react to Power Cycles, and Run/Program Mode changes etc. You can download it at http://literature.rockwellautomation.com/


Stu....

 

[bearsgone]

Hello

If I have Floats or Integers that are being accumulated in the program, I want to upload and modify the program and load it back without loosing values already accumulated. What is the best way to do it in RSLinx 500?

I see that there are options such as "Skip when deleting unused memory" and Static Protection for Data File

Thank you

 

[Tharon]

You must "Upload" the program, which will upload the data files as well. Then make your changes, then download the program (again, downloads the data files). Any data files that changed between your Upload and Download will be lost.

You are using the Micrologix 1400 though. This has Online Editing. You can modify the program without having to Download. The only things you can't do is create new ladder files, create data files, or add to the length of a data file. You can modify existing ladders.