ABB Relion 650 Series Technical Manual page 255

1MRK 506 326-UUS B
7.3.7.2 Time delay
The time delay for step 1 can be either definite time delay (DT) or inverse time delay (TOV). Step 2
is always definite time delay (DT). For the inverse time delay three different modes are available:
• inverse curve A
• inverse curve B
• inverse curve C
The type A curve is described as:
t
=
V Vpickup
−
Vpickup
EQUATION1625 V2 EN-US
The type B curve is described as:
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 details of the different inverse time characteristics are shown in section
characteristics".
TRIP signal issuing requires that the residual overvoltage condition continues for at least the user
set time delay. This time delay is set by the parameter
some special voltage 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.
7.3.7.3 Blocking
It is possible to block Two step residual overvoltage protection (ROV2PTOV, 59N) partially or
completely, by binary input signals where:
BLOCK:
BLK1:
BLK2:
Line distance protection REL650
Technical manual
TD
>
>
TD 480
⋅
0 035 .
−
− >
0 5 .
−
>
TD 480
⋅
0 035 .
+
− >
0 5 .
−
>
blocks all outputs
blocks all pickupand trip outputs related to step 1
blocks all pickup and trip inputs related to step 2
© Copyright 2011 ABB Power Grids. All rights reserved
"Inverse time
t1 and t2 for definite time mode (DT) and by
Section 7
Voltage protection
M15331-10 v5
(Equation 59)
(Equation 60)
(Equation 61)
M15331-18 v4
249