ABB Relion 670 Series RES670, Technical Manual

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Pickup1
PICKUP
TRIP
tReset1
t1
ANSI10000038-2-en.vsd
ANSI10000038 V2 EN
Figure 99: Example for Definite Time Delay stage 1 operation
9.2.7.3 Blocking
It is possible to block Two step overvoltage protection OV2PTOV, (59) partially or
completely, by binary input signals where:
BLOCK: blocks all outputs
BLKTR1: blocks all trip outputs of step 1
BLK1: blocks all pickup and trip outputs related to step 1
BLKTR2: blocks all trip outputs of step 2
BLK2: blocks all pickup and trip outputs related to step 2
9.2.7.4 Design
The voltage measuring elements continuously measure the three phase-to-ground
voltages or the three phase-to-phase voltages. Recursive Fourier filters or true RMS filters
of input voltage signals are used. The phase voltages are individually compared to the set
value, and the highest voltage is used for the inverse time characteristic integration. A
special logic is included to achieve the
1 out of 3 , 2 out of 3 or 3 out of 3 criteria to fulfill the
PICKUP condition. The design of Two step overvoltage protection (OV2PTOV, 59) is
schematically described in figure
100 .
Section 9
1MRK 511 365-UUS A
Voltage protection
294 Phasor measurement unit RES670 2.1 ANSI
Technical manual