To calculate the power quality parameters, the ibaPQU-S central unit samples the input signals synchronously with the grid and calculates the characteristic values on this basis. For this purpose, a synchronization signal (reference signal in ibaPDA) is used and multiplied to a sampling rate between 30 kHz and 40 kHz. For the nominal frequencies of 50 Hz and 60 Hz, a sampling rate of 30.72 kHz is set by default and corrected according to the synchronization signal.

ibaPDA acquires the raw signals on a synchronized time base. Therefore, the signals are re-sampled internally by ibaPQU-S using the sampling rate set in ibaPDA. As a result, individual values may not be available or repeated.

ibaPDA sampling rate	ibaPQU sampling rate	Visible signal distortion
1 ms = 1 kHz	30.72 kHz	None
0.1 ms = 10 kHz	30.72 kHz	Slightly varying slope of the sinus signal
0.05 ms = 20 kHz	30.72 kHz	Varying slope of the sinus signal
0.025 ms = 40 kHz	30.72 kHz	Values are repeatedly duplicated