Problem writing variable to PLC Siemens S7 1500

I have a project Vision 8.1.16 with connection to PLC S71500.
I can read all PLC variable but when try to write a PLC variable, I have this message:

Error writing to indice_ciclo.value: Bad("Bad_CommunicationError: A low level communication error occurred.")

What Can I do???

Thank you very much


Share more information. Is this an OPC connection, or are you using Ignition's Siemens driver? What address are you trying to write? What value are you trying to write? Does anything show up in the gateway log for these failures?

If using an OPC connection to Siemens' OPC server in the PLC, are you reading structures or single elements? If structures, are you writing the whole structure?

I'm using a Ignition's Siemens driver S71500 to connect Ignition at Siemens CPU 1513.
THis problem there is for all variables(integer, short, boolena etc...). Sometimes write operation is ok, sometimes no and there is this message:

Bad_CommunicationError: A low level communication error occurred.

In the Device configuration of Ignition, PLC is connected
I attached wrapper log

wrapper.log (310.5 KB)

Is there a limit of Tag to connect at same device???
I create a new device connected at the same Plc and I utilize this device only for 20 tags: I' don't have the problem.
Can I create more device connected at same PLC Siemens to divide tags between different device????

There's no limit enforced in Ignition.

The logs you uploaded are full of errors happening during a write. It looks like you have some code that is trying to write a null value to a String tag multiple times per second.

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