ABB Relion 650 Series Technical Manual page 249

1MRK 506 326-UUS B
t
=
V Vpickup
32
⋅
Vpickup
ANSIEQUATION2287 V2 EN-US
The type C curve is described as:
t
=
V Vpickup
32
⋅
Vpickup
ANSIEQUATION2288 V2 EN-US
The highest phase (or phase-to-phase) voltage is always used for the inverse time delay
integration, see
section "Inverse time characteristics"
Voltage
VA
VB
VC
ANSI05000016 V1 EN-US
Figure 124: Voltage used for the inverse time characteristic integration
A TRIP requires that the overvoltage condition continues for at least the user set time delay. This
time delay is set by the parameter
level dependent time curves for the inverse time mode (TOV). If the PICKUP condition, with respect
to the measured voltage ceases during the delay time, the corresponding PICKUP output is reset.
7.2.7.3 Blocking
It is possible to block two step overvoltage protection (OV2PTOV ,59) partially or completely, by
binary input signals where:
Line distance protection REL650
Technical manual
480
TD
⋅
0 035 .
−
− >
0 5 .
−
>
TD 480
⋅
0 035 .
+
− >
0 5 .
−
>
Figure 124. The details of the different inverse time characteristics are shown in
© Copyright 2011 ABB Power Grids. All rights reserved
t1 and t2 for definite time mode (DT) and by selected voltage
Section 7
Voltage protection
(Equation 57)
(Equation 58)
Inverse Time Voltage
Time
en05000016_ansi.vsd
M15330-20 v4
243