Differences
This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
en:sw:01-mervis:multiple-history-intervals-hidden [2020/06/01 13:24] jan_kozak |
en:sw:01-mervis:multiple-history-intervals-hidden [2021/08/05 14:52] (current) avsetula [Asynchronous history logging] |
||
---|---|---|---|
Line 1: | Line 1: | ||
~~NOTOC~~ | ~~NOTOC~~ | ||
====== Advanced history log configuration ====== | ====== Advanced history log configuration ====== | ||
+ | <WRAP group> | ||
+ | <WRAP half column 81%> | ||
This guide demonstrates how to log historic values in [[#multiple_logging_intervals|different intervals]] and also how to set up and use the [[#asynchronous_history_logging|asynchronous history logging]] into a database. By using this feature you can considerably decrease the memory space needed for history logs, increasing the duration of PLCs backup - this is useful especially in case of backing up a large amount of data (variables). The solution is also a good choice for projects in which the PLC is connected to Mervis DB via connections charged by used data volume. | This guide demonstrates how to log historic values in [[#multiple_logging_intervals|different intervals]] and also how to set up and use the [[#asynchronous_history_logging|asynchronous history logging]] into a database. By using this feature you can considerably decrease the memory space needed for history logs, increasing the duration of PLCs backup - this is useful especially in case of backing up a large amount of data (variables). The solution is also a good choice for projects in which the PLC is connected to Mervis DB via connections charged by used data volume. | ||
+ | </WRAP> | ||
+ | <WRAP half column 15%> | ||
+ | ;;# | ||
+ | <html><span class="dev-tag dev-patron">Patron</span></html> \\ | ||
+ | <html><span class="dev-tag dev-neuron">Neuron</span></html> \\ | ||
+ | <html><span class="dev-tag dev-gate">Gate</span></html> \\ | ||
+ | <html><span class="dev-tag dev-unipi11">Unipi 1.1</span></html> \\ | ||
+ | <html><span class="dev-tag dev-axon">Axon</span></html> | ||
+ | ;;# | ||
+ | </WRAP> | ||
+ | </WRAP> | ||
Generally speaking, we recommend setting the save periods as long as possible to save up the PLC’s memory and decrease the load on both your network and servers. | Generally speaking, we recommend setting the save periods as long as possible to save up the PLC’s memory and decrease the load on both your network and servers. | ||
Line 62: | Line 75: | ||
<WRAP center round info 85%> | <WRAP center round info 85%> | ||
- | A typical application is a temperature sensor (ie. an outdoor thermometer), for which we do not need to store its exact value. Instead, we can log the temperature value only if it changes by more than ± 1°C compared to the last logged value. By doing so, we can ensure only relevant data will be logged. | + | A typical application is a temperature sensor (ie. an outdoor thermometer), for which we do not need to store its exact value. Instead, we can log the temperature value only if it changes by more than ±1 °C compared to the last logged value. By doing so, we can ensure only relevant data will be logged. |
</WRAP> | </WRAP> |