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Meeg

Recover large data table after power failure

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I have a question regarding Data Tables and the "retained" option. I have some rather large tables, to big to have them all as retained. But I still want to keep the values in case of Power failure. 

In your help function it is noted that Data Tables reside the SD card.. Still there is an option if they should be "retained". But is it not retained anyway if it is stored in the SD?  Will they always be recovered from the SD card at power up?  Or does it have to be done using the "store to file" and "load from file" functions? In my application is acceptable to store the tables periodically (once every hour or day) even if i loose the newest (unstored) data on the recovery.

 Also in your help function a ladder function "Initialize Data Table" is mentioned.: "In most cases, Data Tables values should be initialized after power-up (but i can not find this initialize" function). 

Please help me to understand the best way of doing this... ?

Regards

Meeg

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The SD part is related to Store to file and load to file.

There is a Ladder element called  Clear DTI, which should clear all the values to the default (0 / empty) values.

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So if I understand you correct:

Data Tables are not stored in the SD card before the "store to file" command is executed.

- "load from file" can be used at initialisation (after Power failure) in order to recover the stored values?

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Correct, but even if there is a power failure, since you store the table in retained memory, then it is backed-up using battery, so it should retain the values unless the battery is low.

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