IEC operator: Limiting.
OUT := LIMIT(Min, IN, Max) means:
OUT := MIN (MAX (IN, Min), Max)
Max is the upper and Min the lower limit for the result. Should the value IN exceed the upper limit Max, LIMIT will return Max. Should IN fall below Min, the result will be Min.
IN and OUT can be any type of variable.
Example in ST:
Var1:=LIMIT(30,90,80); (* Result is 80 *);
Example in FBD:
