Hello,

i´ve a project where i want to read values from multiple slaves over modbus. The slaves are elektric meters, and the master would be the S7-1215C with a CM1241.

I had already contact with siemens support and we managed to read any value that is one word long, without problems.

But when i try to read a value that´s two words long i get an error that the parameters are incorrect.  We checked the parameters and i even sent the project to siemens to verify that it should work.

Has anyone experienced this kind of problem?

Thank you,

Martin Herrmann

Hello sipherrmann;

I just need to ask for something you may miss.
After selecting the data length which should be 2 ( as it will be described as a number of words, have you points for a double word also in you pointer data?? as it should be for e.g P#M0.0 WORD 2 or P#M0.0 DWORD 1

If your problem solved, Just let me know

otherwise, send to us the status code so we could help you with solutions.

Regards;

Ahmed Kadry

Thank you for your replies.

The error code is 818D. I checked the help and told the support, but he confirmed that the parameters should be correct.

For the data pointer, i used a 8 word int array. I have also tried a bigger array, i think with 50 elements, and tried to change the array type to byte and word and used different lenght parameters, none helped but changed the error codes to errors refering to invalid parameters.

Dear freinds

I have similar problem.

when I read 8 words or less, there is no problem. But if I try to read more data, a data length error appear. It seems that something limit the data length but I do not know which parameter to modify it.

please help