FB_INSTANCE_DOUBLE_CALL

Severity: warn

The same FB instance is invoked more than once within one POU's scan.

Why it matters. FB instances hold state between calls. Two calls in one scan means the second overwrites outputs the first produced, plus any internal counters / timers tick twice per scan.

Settings. No check-specific config.

Trigger.

T1(IN := xA, PT := T#1s);
T1(IN := xB, PT := T#1s);          (* fires *)

The bot posts.

🟧 warn  FB_INSTANCE_DOUBLE_CALL
FB instance T1 called 2 times in FB_Diagnostics
An FB instance holds state between calls. Multiple calls in one
scan overwrite outputs from earlier calls. Lines: 68, 71.

Fix. Use one instance per call site, or consolidate the calls behind a single condition.