Voltage-Restrained Time Overcurrent Protection Vrpvoc (51V) - ABB Relion Technical Manual

1MRK 502 048-UUS A
8.10
8.10.1
8.10.2
8.10.3
Technical manual
Voltage-restrained time overcurrent protection
VRPVOC (51V)
Identification
Function description
Voltage-restrained time overcurrent
protection
Functionality
Voltage-restrained time overcurrent protection (VRPVOC, 51V) function is
recommended as a backup protection for generators.
The overcurrent protection feature has a settable current level that can be used either with
definite time or inverse time characteristic. Additionally, it can be voltage controlled/
restrained.
One undervoltage step with definite time characteristic is also available within the
function in order to provide functionality for overcurrent protection with undervoltage
seal-in.
Function block
VRPVOC (51V)
I3P* TRIP
V3P* TROC
BLOCK 27 Trip
BLKOC PICKUP
BLKUV PU_OC
27 PU
IMAX
VUmin
ANSI10000118-3-en.vsd
ANSI10000118 V3 EN
Figure 125: VRPVOC (51V) function block
IEC 61850 IEC 60617
identification identification
VRPVOC I>/U<
Section 8
Current protection
ANSI/IEEE C37.2
device number
51V
273