DIFD PLC Omron :
DIFD(14) - Differentiate Down.
DIFD(14) turns ON the designated bit (B) for one scan on reception of the trailing (falling) edge of the input signal.
B: --- Bit --- IO, AR, HR, LR.
PLF PLC Mitsubishi :
PLF is Pulse Falling
When PLF instruction is executed, object devices Y and M operate for one operation cycle after the drive input signal has turned OFF.
DIFD PLC Keyence :
DIFD is Diff down or Differentiate down
Scans the target relay once (down differential) at the down edge of the previous state.
See : Simulator DIFD PLC or PLF PLC