Setting Guidelines; General; Setting Of Common Parameters - ABB Relion 670 Series Applications Manual

1MRK 511 358-UUS A
In cases where the line can have a weak-infeed of zero sequence current this function shall be
avoided.
A criterion based on delta current and delta voltage measurements can be added to the fuse
failure supervision function in order to detect a three phase fuse failure. This is beneficial for
example during three phase transformer switching.
12.2.3

Setting guidelines

12.2.3.1

General

The negative and zero sequence voltages and currents always exist due to different non-
symmetries in the primary system and differences in the current and voltage instrument
transformers. The minimum value for the operation of the current and voltage measuring
elements must always be set with a safety margin of 10 to 20%, depending on the system
operating conditions.
Pay special attention to the dissymmetry of the measuring quantities when the function is used on
long untransposed lines, on multicircuit lines and so on.
The settings of negative sequence, zero sequence and delta algorithm are in percent of the base
voltage and base current for the function. Common base IED values for primary current (
primary voltage (
setting GlobalBaseSel is used to select a particular GBASVAL and used its base values.
12.2.3.2

Setting of common parameters

Set the operation mode selector
The voltage threshold
below the minimum operating voltage that might occur during emergency conditions. We propose
a setting of approximately 70% of
The drop off time of 200 ms for dead phase detection makes it recommended to always set
Enabled since this will secure a fuse failure indication at persistent fuse fail when closing the
to
local breaker when the line is already energized from the other end. When the remote breaker
closes the voltage will return except in the phase that has a persistent fuse fail. Since the local
breaker is open there is no current and the dead phase indication will persist in the phase with the
blown fuse. When the local breaker closes the current will start to flow and the function detects
the fuse failure situation. But due to the 200 ms drop off timer the output BLKZ will not be
activated until after 200 ms. This means that distance functions are not blocked and due to the
"no voltage but current" situation might issue a trip.
The operation mode selector
requirements. The mode selector enables selecting interactions between the negative sequence
and zero sequence algorithm. In normal applications, the
selecting negative sequence algorithm or
studies or field experiences shows that there is a risk that the fuse failure function will not be
activated due to the system conditions, the dependability of the fuse failure function can be
increased if the
negative and zero sequence based algorithms are activated and working in an OR-condition. Also
in mode
has the highest magnitude of measured negative or zero sequence current will operate. If there is
a requirement to increase the security of the fuse failure function
Application manual
VBase ) and primary power ( SBase ) are set in Global Base Values GBASVAL . The
VPPU is used to identify low voltage condition in the system. Set VPPU
OpModeSel has been introduced for better adaptation to system
OpModeSel is set to V0I0 OR V2I2 or OptimZsNs . In mode V0I0 OR V2I2 both
OptimZsNs both negative and zero sequence algorithms are activated and the one that
Operation to Enabled to release the fuse failure function.
VBase .
V0I0 for zero sequence based algorithm. If system
Secondary system supervision
OpModeSel is set to either V2I2 for
OpModeSel can be selected to
Section 12
IP15000-1 v1
M13683-3 v5
IBase ),
M13683-9 v9
SealIn
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