Too many monitoring variables

  • anverheul

    anverheul - 2005-06-07

    Online mode gives mainly 'Too many monitoring variables' messages, and no access to variables.

    Background info:


    I'm working on an CodeSys application where recipe data is stored in several ARRAYs of STRUCTs. As we have lots of recipe data, there's quite some entries in the arrays, and quite some fields in the structs.

    Recipe data can be modified both locally (with CodeSys visualisation) or 'remotely' (with an PC application via OPC).



    I'm using CoDeSys in combination with Advantech WinCE based IPCs.



    1. How does the option 'Surpress monitoring of complex types' work. I can't notice any difference when this option is selected.

    2. Is it possible to have monitoring of variables turned off by default, rather than having to specify '{flag nowatch}' for each and every (array/struct) variable.

    3. Can you confirm that the exporting of symbol file entries only has to do with OPC, and has nothing to do with online monitoring? If there is some relation, can you explain this a bit?

    Thanks in advance,

    Arie N. Verheul

  • Manfred Werner

    Manfred Werner - 2005-06-23

    background: depending on the type of hardware, the buffer size for communication between PLC and PC is limited.

    As the CoDeSys monitoring data is cyclus consistent (all data you see belong to one PLC cycle), they are written to a buffer. If data exeeds buffer size (typically 5000 bytes for small PLC), you get this error message.

    But there is help:

    Since version 2.3.3, CoDeSys monitors as much as it can and for the rest it shows instead of a monitoring message "too many monitoring data". No message box any more. Please update.

    1. 'Surpress monitoring of complex types'

    CoDeSys can monitor A[i]. In case of an array of struct this can be time consuming, and can even rise cycle time of a PLC cycle. Therefore there is an option to switch it off.

    Standard is not to switch it off.

    1. Turn monitoring off

    Should not be necessary with the latest version.

    1. Confirmed. Only when using OPC or the ARTI (, the Symbolfile is used.

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