Problem reading tags from Siemens S7-1500 PLC

luis.3.flores · November 3, 2020, 3:55pm

I am having an issue trying to read the tags from a PLC S7-1500.
I have access level set as “Full access (no protection” and the connection mechanism enabled for “permit access with PUT/GET communications from remote partner”.

I am using the Ignition driver for S7-1500 over ethernet and the PLC is connected.

On the designer I added an OPC tag named [s71500]DB66,STRING44.20 so I can read the following tag:

I get error 8104 on the logs.

Any idea what is wrong ?

pturmel · November 3, 2020, 3:57pm

Have you disabled optimized access for the data block(s) you are trying to read?

luis.3.flores · November 3, 2020, 3:58pm

Yes.

pturmel · November 3, 2020, 4:07pm

Hmm. No further idea. @chi or @zxcslo are the go-to guys for Siemens.

ps. Start new topics in the future. Necromancy is not always noticed by those who might be able to help.

zxcslo · November 3, 2020, 5:06pm

Well… the error 8104 means that access to the address is not allowed. So there must be something with the “Permit access with PUT/GET…” in the HW configuration of the PLC.
Can you try to compile the PLC program again and download it to the PLC?
Is this (STRING) the only tag you can’t read?

luis.3.flores · November 3, 2020, 5:18pm

I cannot read any tag at all. I will try to compile and download it again.

luis.3.flores · November 3, 2020, 5:44pm

I compiled the hardware configuration again and downloaded and it is working now! Thanks a lot!