VC4 Visu on PPT50 very slow


Morging everyone,

I have a problem with my speed when i want to switch to another page on my visualisation
on the PPT50. It takes about 3 sec. to change to another page. Below you find my configured settings. I already tryed to change the refresh time down to 200ms.
But my speed is still about 3sec. to change pages.
What could be the reason?
My VC4 has 30 pages at all.


since the pages of VC4 are rendered on the server (PLC), the performance depends also on the PLCs free idle time and DRAM, please see here for some details:

If the servers performance is the cause, then also using a VNC client on your development PC should be slow, not only on the PPT50. How does the VNC viewer on your PC behaves?
What PLC you’re using? Could you please check the CPU load and free DRAM with SDM?

Best regards!


above you see my performance of the plc.
the used plc: X20CP0483.



ok thanks, does not look too bad.
The PLC isn’t a very fast one, so please check the optimization hints for picture chance over times on that page:

First of all I recommend to check:

  • if you have overlapping transparent controls
  • if you use bitmap borders, please check here for performance issues: B&R Online Help
  • if the VNC client settings meet the settings of the VC4 visualization (about color-depth)
    • please also check if a compression / encoding is set in the VNC client, sometimes such methods slow down the page rendering - with a LAN connection, normally a compression isn’t needed but takes extra time from the server to compress the frame buffer before transferring the initial image.
  • if you’re using bitmap borders, color gradients, and so on please consider if you could use a more simple / “clean” layout, this would speed-up the page generation.
    • you could test this for example by inserting one page with a different style sheet to see if and how the computing time changes.

Hope this infos help a bit to improve the performance,
best regards!


thanks for so much feedback.
When I reduce the disolay to 8Bit Colormode, then it’ s working in
an acceptable speed.


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