ABB Relion 670 Series RES670, Техническое руководство

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21.2.6.2 Design
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 511 365-UUS A
Section 21
IED hardware
Phasor measurement unit RES670 2.1 ANSI 765
Technical manual