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Schneider Unity Pro - PLC vs Local Init Values & Current Tag Values

Schneider Unity Pro - PLC vs Local Init Values & Current Tag Values

Schneider Unity Pro - PLC vs Local Init Values & Current Tag Values

Hi All,

Can anyone explain to me:

1) What are 'PLC initialisation values",
2) What are 'Local initialisation values', and
3) Why I am getting a warning in unity pro 'the initialisation values in the PLC are different from those of the local application (see link below):


According to the link below:


The tags with 'save' checked are the ones that are saved in the offline program when 'update initial values with current values' is performed.

So, are 'PLC initialisation values' simply the current tag values for 'SAVE' tags and are 'Local initialisation values' the data stored in the offline program for these tags?

Why do they have to make this so difficult to understand? A PLC is a PLC, every PLC I have used (Siemens, Rockwell) it's easy and essential to upload the current tag values into the backup. Why is this so hard for me to understand?


RE: Schneider Unity Pro - PLC vs Local Init Values & Current Tag Values

It is a two step process. GE RX3i is the same way. Upload the program with the save tag values checked. Then re-download the program and that will set the initial values in the process to the value you uploaded in the first step. Be aware that the initial values are only used on a "cold start". A cold start is when memory has been wiped in some way. A normal power cycle will not cause a cold start. In the M340 line only analog data values are saved. Boolean data is not saved through a power cycle.

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