
Drive PLC Developer Studio
IEC 61131-3 Standard functions
14-18
l
DDS EN 2.3
14.7.3 TOF
Timer off-delay
TOF(IN, PT, Q, ET) means:
• IN and PT are input variables of type BOOL or TIME.
• Q and ET are output variables of type BOOL or TIME.
• As soon as IN is FALSE, ET will count the time in milliseconds until the value equals that in
PT and then remain the same.
• Q is FALSE if IN is FALSE and ET equals PT. Otherwise Q returns TRUE.
Q thus has a falling edge when the time set in milliseconds in PT has expired.
Graphic representation of TOF’s time sequence:
Examples
Declaration:
TOFInst : TOF;
IL FBD
CAL TOFInst(IN:=VarBOOL1, PT:=T#5s)
LD TOFInst.Q
ST VarBOOL2
ST
TOFInst(IN:=VarBOOL1, PT:=T#5s);
VarBOOL2:=TOFInst.Q;
Comentários a estes Manuais