ABB CL Series, Руководство по применению

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Display system program cycle
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1SVC 440 795 M1100
COM-LINK data access during the program cycle
The data exchange with the point-to-point connection can
be carried out in any segment of the program cycle. This data
exchange increases the cycle time with both active and
remote stations. Only use data that is absolutely necessary.
Loading visualization data
When setting a program to RUN that contains visualization
data, the contents of the screens to be displayed have to be
loaded.
The time required for loading in the event of a screen change
depends on the size of the screens to be loaded. During a
screen change, the new screen is loaded from the screen
memory into the RAM. The display system checks every
200 ms whether the new screen has to be loaded.
The loading time can be calculated as follows:
Screen size in byte multiplied by 80 μs.
Example:
Screen size 250 bytes:
The loading time for the screen is: 250 × 80 μs = 20 ms
The loading of screen data and screen changes can be
implemented in any segment of the program cycle. Take this
behaviour into account when considering the reaction time
of your entire control system.
h
If you require the display system to have a small cycle time:
Use several small screens so that the loading time is not too
long during a screen change. Only display necessary
information in the screens concerned (
a section “Memory
layout”, page 268).