In Trend/Alarm Storage there is setting Maximum number of records.
It seems reasanoble to also show how many PLC memory will be occupied by sqlite file in this case.
Right now I want to know approximate memory space for 1 record in Trend/Alarm storage.
Still interesting in answer.
Originally created by: D. Kugler
because it's interesting for me too, I started a test with 1000, 2000 and 3000 alarms max. and checked the file size of the sqlite.db. It looked like if no latch variable is used, one message takes about 164-188 byte. If f.eg. a DINT as latch variable is included, it took rund about 200 bytes. So, I think it's depending on configuration and there is no fixed size. Maybe codesys stuff has an answer, what's the maximum size/alarm is?!
If space in ram is a problem I would prefere to set the radiobutton to Maximum storage size. Fill the storage by blinking an alarm and have a look, how many alarms are in the history max.
Maybe I can help you with your question. I'm testing the storage functionality on the EPEC 6107 HMI with next trend storage configuration:
Measure in every n-th cycle : 5 (100ms)Max number of vars: 5, but I use only 3
Sqlite DB size for period 7-1-2020 17:1:36 - 9-1-2020 9:50:22 is 65974272 bytes
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