Filters - ABB ACSM1 Firmware Manual

316

Filters

FILT1
(10069)
Illustration
Execution time
Operation
Inputs
Outputs
Standard function blocks
7.59 µs
The output (O) is the filtered value of the input (I) value and the previous output value
(O ). The FILT1 block acts as 1st order low pass filter.
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Note: Filter time constant (T1) must be selected so that T1/Ts < 32767. If the ratio
exceeds 32767, it is considered as 32767. Ts is the cycle time of the program in ms.
If T1 < Ts, the output value is the input value.
The step response for a single pole low pass filter is:
-t/T1
O (t) = I(t) × (1 - e )
The transfer function for a single pole low pass filter is:
G(s) = 1/ (1 + sT1)
Input (I): REAL
Filter time constant input (T1): DINT, 1 = 1 ms
Output (O): REAL