Setting Guidelines - ABB RELION 670 Series Applications Manual

1MRK 505 343-UEN B
nondirectional distance zones also gives a fast fault clearance when energizing a bus from the
line with a short circuit fault on the bus.
Other protection functions like time-delayed phase and zero-sequence overcurrent function
can be connected to ZCVPSOF to increase the dependability in the scheme.
When the voltage transformers are situated on the bus side, the automatic switch onto fault
detection based on dead-line detection is not possible. In such cases the deadline detection is
bypassed using the breaker closing status and the switch onto fault logic is activated.
7.18.3

Setting guidelines

The parameters for automatic switch onto fault logic, voltage- and current-based function
ZCVPSOF are set via the local HMI or Protection and Control Manager PCM600.
The distance protection zone used for instantaneous trip by ZCVPSOF has to be set to cover
the entire protected line with a safety margin of minimum 20%.
Common base IED values for primary current (
power (
GlobalBaseSel is used to select GBASVAL for reference of base values.
Operation : The operation of ZCVPSOF is by default set to On . The parameter must be set to
Off if ZCVPSOF is not to be used.
IPh< is used to set the current level for the detection of a dead line. IPh< is, by default, set to
20% of
load current. In many cases, the minimum load current of a line is close to zero and even can be
zero. The operating value must exceed the maximum charging current of an overhead line
when only one phase is disconnected (mutual coupling in the other phases).
UPh< is used to set the voltage level for the detection of a dead line. UPh< is, by default, set to
70% of
suitability in the actual application.
AutoInitMode : automatic activating of ZCVPSOF is, by default, set to DLD disabled , which
means the dead-line logic detection is disabled. If an automatic activation of the dead-line
detection is required, the parameter
Current & Voltage .
AutoInitMode is set to Voltage , the dead-line detection logic checks that the three-phase
When
voltages are lower than the set
AutoInitMode is set to Current , the dead-line detection logic checks if the three-phase
When
currents are lower than the set
AutoInitMode is set to Current & Voltage , the dead-line detection logic checks that both
When
three-phase currents and three-phase voltages are lower than the set
Otherwise, the logic is activated by an external BC input.
tSOTF : the drop delay of ZCVPSOF is, by default, set to 1.0 seconds, which is suitable for most
applications.
tDLD : The time delay for activating ZCVPSOF by the internal dead-line detection is, by default,
set to 0.2 seconds. It is suitable in most applications. The delay shall not be set too short to
avoid unwanted activations during transients in the system.
Mode : The operation of ZCVPSOF has three modes for defining the criteria for tripping. The
setting of
Application manual
SBase ) are set in the global base values for settings function GBASVAL.
IBase . It shall be set with a sufficient margin (15–20%) below the minimum expected
UBase . This is a suitable setting in most cases, but it is recommended to check the
Mode is, by default, UlLevel , which means that the tripping criterion is based on the
IBase ), primary voltage ( UBase ) and primare
AutoInitMode has to be set to either Voltage , Current or
UPh< level.
IPh< level.
Section 7
Impedance protection
M13855-4 v8
IPh< and UPh< levels.
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