S7-1200

[marco]

Hi everyone,
I am trying to read value from s7-1200 siemens by using s7 protocol.
The connection test works fine but I am not able to read and write value. It shows an error message 27.
Thanks in advance for your help

[Suppanel]

Hello,
Thanks for your inquiry.
Please verify that you have "Optimized Block Access" disabled in your DB preferences in your PLC project.

Regards.

[Lois20000]

Hello im new here, im using 315DP and get the same error.
I try to read a periferie Input word.

Thanks.

[Suppanel]

If you mean a fieldbus remote input then Suppanel can't access it. Try copying the input to an internal bit of the PLC.

Siemens has never published the communication protocol for its PLCs. Suppanel and others HMI use an old communication library that has many limitations.

Thanks for you inquiry.