toolTIA PortalVerified · sol.ls-electric.com
TIA Portal C-S7-1234 — Compile: undefined symbol
Alarm — operational, inspection needed
CAUSE
Why does it occur?
A PLC tag or DB variable is referenced in the program but not declared.
REMEDY · Step by step
How to fix it?
Add the tag to the tag table/DB, then compile for consistency.
Do not reset repeatedly before identifying the cause. Repeated resets while ignoring a trip/alarm can cause secondary damage (IGBT failure, motor winding damage, etc.).
SOURCE
Related manual page
Summary based on the official Siemens AG manual. For accurate and complete information, always consult the official manual.
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