Lenze PLC Designer PLC Designer (R2-x) - Manual (Page 497)

L-force | PLC Designer
IEC Operators and additional norm extending functions

DMS 3.2 EN 02/2011 TD29 495
9.9.9 TRUNC
PLC Designer IEC operator: Converting from REAL to INT. The whole number portion of
the value will be used.
When you perform a type conversion from a larger to a smaller type, you risk losing
some information.
Example in IL:
LD 2.7
TRUNC
GE %MW8
Examples in ST:
i:=TRUNC(1.9); (* Result is 1 *)
i:=TRUNC(-1.4); (* Result is -1 *).