IMPLICIT_TYPE_CONVERSION

Severity: info. PLCopen: CP25 — data-type conversions shall be explicit.

A binary +, -, *, or / mixes operands from different numeric type families: an INT-family operand (INT, DINT, LINT, BYTE, WORD, DWORD, …) on one side and a REAL-family one (REAL, LREAL) on the other. The runtime inserts an implicit conversion; PLCopen wants the cast to be visible in the source.

Settings. No check-specific config. This check uses a deliberately conservative subset of type detection — declared variable types and literal shape (3.14 vs 42 vs 16#FF) — so subtler cases (typed temporaries, sub-expressions involving function returns) are not flagged. Full type inference would catch more but isn't on the roadmap.

Trigger.

VAR
    i : INT;
    r : REAL;
END_VAR
r := i + 1.5;             (* fires — INT and REAL mixed in the + *)

The bot posts.

🟦 info  IMPLICIT_TYPE_CONVERSION
Implicit type conversion in 'i + 1.5' (mixing INT and REAL) — PLCopen CP25

Fix. Insert an explicit cast: r := INT_TO_REAL(i) + 1.5;. Or make both operands the same type up front.