Blocking; Design - ABB Relion 670 Series Technical Reference Manual

Section 7
Voltage protection
7.3.2.3
7.3.2.4
244
Un<
START
TRIP
tResetn
tn
IEC10000040 V1 EN
Figure 124: Example for Definite Time Delay stage operation

Blocking

It is possible to block Two step residual overvoltage protection ROV2PTOV
partially or completely, by binary input signals where:
BLOCK:
BLKTR1:
BLKST1:
BLKTR2:
BLKST2:

Design

The voltage measuring elements continuously measure the residual voltage.
Recursive Fourier filters filter the input voltage signal. The single input voltage is
compared to the set value, and is also used for the inverse time characteristic
integration. The design of Two step residual overvoltage protection (ROV2PTOV)
is schematically described in figure 125.
blocks all outputs
blocks all trip outputs of step 1
blocks all start and trip outputs related to step 1
blocks all trip outputs of step 2
blocks all START and trip inputs related to step 2
1MRK 505 208-UEN B
IEC10000040-1-en.vsd
Technical reference manual