Error "Bad_Failure" when writing empty string to tag in Ignition

Ignition
1

Hi everyone,

I'm encountering an issue in Ignition SCADA when writing an empty string ("") to a tag. After running my script, the tag value updates to an empty string as expected, but I still get a "Bad_Failure" error popup. Here are the details:

Error writing "" to tag [Default]TestCompany/ML/A3/ObjID_Des Bad_Failure

  • Tag Path: [Default]TestCompany/ML/A3/ObjID_Des
  • Error Message: Error writing "" to tag [Default]TestCompany/ML/A3/ObjID_Des Bad_Failure
  • Script Behavior: My script sets ObjID_Des to "". The tag value updates correctly, but the error persists.
  • Tag Configuration:
    -- Access Rights: Read_Write
    -- Tag Quality: Good
    -- Data Type: String
    -- OPC PLC Settings: Confirmed that the PLC allows writing empty string values
    -- Security: Configured to allow Read_Write for anyone
    What I've Tried:

Verified that the tag is writable and has no security restrictions.
Checked the OPC server connection, which is stable.
Confirmed the PLC accepts empty strings for this tag.

Questions:

  • Why does writing an empty string trigger a Bad_Failure error even though the tag updates correctly?
  • Is there a specific configuration in Ignition or the OPC server I should check to allow empty string writes without errors?
  • Could this be related to the tag's OPC item settings or a bug in Ignition?

Thanks in advance!

2

Is this a third party OPC server or Ignition OPC UA + driver? If Ignition, which driver? What’s the OPC Item Path of the tag?

3

What if you write an ASCII 0x00, does it error?