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Design SECTION 20 Best Practices
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SECTION 20
Best Practices
This chapter details the best practices to get the most from CX-Supervisor
including how to plan and design your application.
20-1 Design
This section covers some good design practices. There is no doubt, as with
everything in life that a good design is essential and creating a good CX-
Supervisor application is no different. Poorly designed applications may run
slower, provide slower user feedback, be difficult to maintain - increasing costs
and in some cases not fulfil all User Requirements resulting in the application
being rewritten. Never fall into the trap "code first, think later".
20-1-1 Design your page layouts and navigation flow
Traditional design works well for most applications. Providing an application
with a clear structure can make applications very easy to navigate even if they
have many pages.
• Create a Main overview / navigation page. This can include basic
information like company logo and date/time. If the application will be
using security levels provide buttons to login.
• Add links from the main page to detailed system areas with either buttons
or schematic diagram e.g. Process 1, Process 2.
• Add links from the main page, if required, to pages dedicated to Alarms,
Diagnostics, Reports, Data Logging, Statistics etc
• If the system has repeated functions e.g. 5 similar machines, instead of
creating 5 pages think about creating 1 page that can show data for any
machine. This can be achieved using indirection and/or keeping data in
arrays, and just setting the index to display the machine you require. Minor
differences (e.g. a button for Process 1 only) can be shown or hidden
depending on the index. This will speed up development and also help
when the application is maintained.
Organise the pages sensibly on screen. Make sure that only the pages that
are necessary are open. When a page is no longer needed close it. CX-
Supervisor will update all pages that are open, therefore if lots of pages are
open then it may be doing a lot of unnecessary work that will slow down the
application. For pages that are displayed in the same place, set the 'Display
Mode' property to 'Replace'. This allows pages to automatically be closed
when a new page is loaded.
20-1-2 Use Logical Point names instead of physical addresses
Logical point names (like 'Boiler_3_Pressure') provide more flexibility than
physical addresses (like 'D8319') allowing the PLC program and addresses to
be changed, without impacting the SCADA. They also make it much easier
read during development, and more importantly, during maintenance.
• Perform all data conversion in PLC ladder
Although today's PCs have excellent maths performance consider the
format of the PLC data and how it will be used. It can be temping to scale
a point value when read e.g. to change the units of measurement, or
Note: If the Logical symbols are created in CX-Programmer, it can link them to a CX-
Server file which CX-Supervisor can then 'Import' into the Points Editor. This is
a very quick method of creating all the required points.