What does Preload on build changes do in the Control Expert project settings?
Issue
Preload on build changes setting
Product Line
Modicon M580
Environment
EcoStuxure Control Expert
Solution
"Preload on build changes" + "Effective build changes timeout" => 'the preload of the new Data Dictionary in the PLC lets enough time for the client to relearn the new application variable mapping'
In another words, Control Expert does an Online change, then at the end of the Build...
- if "Preload on build changes" is unchecked, the changes are applied into the PLC directly and the client detects the inconsistency (=> #Bad is seen during the resynchronization)
- if "Preload on build changes" is checked, Control Expert preloads the modifications into the PLC then waits for the "Effective build changes timeout" (40s by default) before applying the changes into the PLC ; during this time the client still continues to animate the current Data Dictionary variables AND in parallel the client reloads the new Data Dictionary ; at the end of the "Effective build changes timeout" Control Expert applies the Changes to the PLC, so the client detects the inconsistency and the client does a quick switch to be mapped now on the new Data Dictionary which is ready.