ABB RELION 650 SERIES, Technical Manual

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20.2.6.2 Design
M13666-3 v2
The Analog digital conversion module input signals are voltage and current from
the transformer module. Shunts are used to adapt the current signals to the
electronic voltage level. To gain dynamic range for the current inputs, two shunts
with separate A\D channels are used for each input current. In this way a 20 bit
dynamic range is obtained with a 16 bit A\D converter.
Input signals are sampled with a sampling freqency of 5 kHz at 50 Hz system
frequency and 6 kHz at 60 Hz system frequency.
The A\D converted signals goes through a filter with a cut off frequency of 500 Hz
and are reported to the numerical module (NUM) with 1 kHz at 50 Hz system
frequency and 1,2 kHz at 60 Hz system frequency.
1MRK 506 382-UEN A
Section 20
IED hardware
Line distance protection REL650 2.2 IEC 839
Technical manual