How should I read S7-300 DB addresses (e.g. DB916,DBD228) in Ignition OPC?

Ignition
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1

I'm configuring an OPC Tag in Ignition to read a value from a Siemens S7-300 PLC.

The PLC address I was given is:

DB916,DBD228

The OPC device name in Ignition is:

L12_VarioAsep

The OPC Item Path is currently configured as:

ns=1;s=[L12_VarioAsep]DB916,REAL228

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The tag quality is Good (no errors or Bad quality), so the communication appears to be working. However, the tag value is always 0, even though I expect it to contain a non-zero value.

My questions are:

  • Is this the correct OPC Item Path for the PLC address DB916,DBD228?
  • Should DBD228 be read as REAL228, DINT228, or another data type?

Unfortunately, I don't have access to the PLC project or STEP 7/TIA Portal.

Any suggestions or troubleshooting steps would be greatly appreciated. Thank you!

2

The D is probably DWord, so I'd expect it to look like [Device]DB916,D228 in Ignition