(* @PATH := '\/Functions_Collection' *)
(* @SYMFILEFLAGS := '0' *)
FUNCTION SpeedAdjust : REAL
VAR_INPUT
	i_PrdTnkLvl				: REAL ;
	i_TrgTnkLvl				: REAL ;
	i_IstLvl					: REAL ;
	i_SpeedPerc			: REAL ;
END_VAR
VAR
	a						: REAL ;	(* Angolar Coefficient *)
	b						: REAL ;	(* Constant *)
END_VAR
(* @END_DECLARATION := '0' *)
(* The following function calculates the percentage speed correction to get Product Tank target Level
the equation used is: y = a * PrdTankLvl + b ; that is a = - SpeedPerc / IstLvl; and b = 1 - TrgTnkLvl * a
the function yelds 1.0 at 50% of level; (1 - SpeedPerc) at 80% level; the maximum is (1 + SpeedPerc) *)

i_SpeedPerc := i_SpeedPerc / 100.0 ;
IF i_IstLvl>0 THEN
	a := -i_SpeedPerc / i_IstLvl ;
	b := 1 - (a * i_TrgTnkLvl) ;
	SpeedAdjust := a * i_PrdTnkLvl + b	 ;
	SpeedAdjust := LIMIT(1 - i_SpeedPerc,SpeedAdjust ,1 + i_SpeedPerc) ;
ELSE
	SpeedAdjust := 0.0 ;
END_IF
END_FUNCTION