Hello,

I need to configure the Taglogging archive (Fast and Slow).

A calculation is available in the help:

Where can I find value x or how to determine it? It means: "Bytes across all segments", but it is very little information.

Hello DayMark, 

According to the WinCC specifications, (approximately) 4000 bytes per message is included in the calculation. The number of variables and number of months are the major variables of consideration for calculating memory requirements.

Hope the attachment with the example calculation helps you.

Good Luck! 

Hi,

Yes correct, but this is the alarmlogging, I need to calculate taglogging memory requirements.

Hello,

I still need help with my question. The systemarchive has a fixed amount of byte (31kb) for 1000 messages, do I need this value for the calculation?

Hello DayMark,

see the manual:
"SIMATIC HMI WinCC V7.5 SP1 WinCC Information System"
"Calculating memory requirements"

https://support.industry.siemens.com/cs/ww/en/view/109772961/65809247883

Regards

Georg Berghof

Hello Thank you for the info,

I have seen this calculation in the manual, but I do not understand why Siemens is using 6 bytes and 16 bytes.  

The amount of tags per second I can find it via internal tag: @TLGRT_TAGS_PER_SEC but I have no clue about the memory data.

Hello DayMark,

the 6 Bytes or 16 Bytes depends on the datatype of
the archivetag.
If it is binary (0 or 1) you need only 6 Bytes
per value (inclusive timestamp and flags)
If it is a floating point value you need 16 Bytes
per value (inclusive timestamp and flags).

Regards

Georg Berghof