Chapter 9—C445 Logic Engine and Expansion I/O174 Power Xpert C445 Global Motor Management Relay MN042003EN—January 2019 www.eaton.comFILT—Single-Pole Low Pass FilterThe FILT function block is a single-pole low pass filter that filters the input signal. The timeconstant is defined by FTIME.The filter is implemented per the equation below.For the proper operation of the filter, FTIME has to be greater than or equal to the programscan time.The filter can be pre-initialized using the SET and DATA inputs. When SET is true, theoutput of the filter is pre-initialized with the value specified by the DATA input.ExampleIn the following example, the FILT block is used to filter the Phase A current with the timeconstant at 1 second and the program scan time set at 10 ms. The filtered current is madeavailable through a process data out. The filter is cleared when the motor is stopped.Parameter Data type DescriptionSET BOOL Pre-initialize filter commandDATA INT Pre-initialize filter dataFTIME INT Filter time constant in millisecondsIN INT Signal to be filteredOUT INT Filtered output
