ABB ACSM1 Series, Firmware Manual

Page: 283 / 334

Standard function blocks
283
Inputs Input (X): REAL
-3 dB cutoff frequency input (FRQ): DINT (0…16383 Hz)
Reset input (RESET): Boolean
Outputs Output (Y): REAL
LEAD/LAG
(10071)
Illustration
Execution time 5.55 µs
Operation The output (Y) is the filtered value of the input (X). When ALPHA > 1, the function block
acts as a lead filter. When ALPHA < 1, the function block acts as a lag filter. When
ALPHA = 1, no filtering occurs.
The transfer function for a lead/lag filter is:
(1 + ALPHA
T
c
s) / (1 +
T
c
s)
When RESET input is 1, the input value (X) is connected to the output (Y).
If ALPHA or Tc < 0, the negative input value is set to zero before filtering.
Inputs Input (X): REAL
Lead/Lag filter type input (ALPHA): REAL
Time constant input (Tc): REAL
Reset input (RESET): Boolean
Outputs Output (Y): REAL
LEAD/LAG
69
TLA1 1 msec (1)
X
ALPHA
Tc
RESET
Y
Y(69)